Experimental procedures for excess heat generation from cold fusion reactions

CHAPTER

Experimental procedures for excess heat generation from cold fusion reactions

8

Tadahiko Mizunoa, Jed Rothwellb Hydrogen Engineering Application & Development Company, Sapporo, Japana LENR-CANR.org, Chamblee, GA, United Statesb

Air-flow calorimetry Introduction Anomalous excess heat from metal and hydrogen systems is a long-standing topic in cold fusion research [1–5], although it has sometimes been sidelined by the search for other evidence. The reaction was first thought to be a normal nuclear fusion reaction, which led researchers to focus on confirmation of neutron generation during electrolysis in heavy water [6]. Since then, the focus of study has shifted to the analysis of isotopic changes during electrolysis. Excess heat was occasionally generated during these experiments, usually with a sudden onset [7–10]. Excess heat from the nickel-hydrogen system has been observed, which in some cases might be chemical heat. Despite this, in other experiments, the Ni-H system served as a calibration in comparison with the Pd-D2 system, with the assumption that it was not producing excess heat in these tests [11–14]. Although the excess heat occurs sporadically and not often, many experiments have been performed, so that in the aggregate there are many reports of heat. This report offers reference data and techniques for researchers who plan to conduct similar cold fusion experiments.

Insulated box We use an insulated acrylic box for air flow calorimetry [15] (Fig. 1). Its dimensions are 400 mm
750 mm, height 700 mm (210L). During tests, the inside of the plastic box is covered with reflective padded aluminum insulation. This minimizes losses to radiation. These losses are low in any case, because the cooling air usually keeps the inside of the box at 36°C. The air inlet and outlets are circular, 66 mm in diameter. The inlet is located near the bottom of one side, and the outlet is cut into the top surface. The outlet is connected to a pipe that makes the air flow uniform across all parts of the outlet cross section, to increase the accuracy of the air-flow measurements. The power supplied to the blower is monitored continuously, and is 6.5 W. The outlet air temperature is measured using two platinum resistance temperature devices (RTDs). They are installed at the center of the pipe, Cold Fusion. https://doi.org/10.1016/B978-0-12-815944-6.00008-7 # 2020 Elsevier Inc. All rights reserved.

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Chapter 8 Experimental procedures for excess heat generation

FIG. 1 Acrylic box calorimeter with the insulation. The active and control reactors are placed side-by-side in the box.

one in the stream of air before it reaches the blower, and one after the blower, to measure any heat added to the air by the blower motor. The difference between these two sensor readings is less than 0.1°C (Fig. 2).

Blower The blower was selected taking into account the volume of air during the 5 s data acquisition time; the size of the box; and the amount of heat that we expected to measure. The heat to be measured ranged from a few watts to several hundred watts. The volume of the box had to be between 200 and 400 L for this reason. The air flow rate had to be from 1 to 10 L/s, considering the heat retention (insulation and

FIG. 2 Illustration of the insulated box used for air-flow measurements.

Air-flow calorimetry

117

temperature) of the box. Under these conditions, the temperature inside the box is 15 to 30°C warmer than room temperature. A SanAce B 97 model blower 109 BM 12 GC 2-1 was chosen (Fig. 3). A rubber O-ring was put between the blower and the box wall, and was fixed with an adhesive glue. This seal prevents air leaks and keeps the vibration of the blower from affecting the box. The blower exit is rectangular, 58 mm
38 mm. The wind velocity in a square outlet is uneven. It is better to measure it some distance from the fan, so a 200 mm long cover pipe cylinder made of paper (Fig. 4) was attached in front of the blower outlet. One end is rectangular to fit the blower, and the other end is circular, 66 mm in diameter. This cylinder can be made of paper or plastic. 2 mm-thick urethane insulation is wrapped around the outside of the cylinder.

FIG. 3 Blower with rubber O-ring.

FIG. 4 Paper cylinder.

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Chapter 8 Experimental procedures for excess heat generation

Measurement and data acquisition The data is collected into spreadsheets with 1000–20,000 rows, one row every 5 s. Sample data is shown in Table 1. The heading rows list spreadsheet columns B through K (which are shown as circled letters in Fig. 5), the measurement units in the data logger (volts or degrees Celsius), and the type of measurement. Column A is reserved for the timestamp, and columns L through X are reserved for calculations.

Table 1 Input items from the data logger. B

C

D

E

F

G

H

I

J

K

V

V

V

V

V

deg C

deg C

deg C

deg C

deg C

Blower V Blower A

Pressure

Input V (*24)

Input A (*1.25)

Control Reactor Surface

Air Inlet

Air Outlet

Air Outlet 2

Reactor Surface

10.078 10.078 10.078

0.008 0.007 0.008

0.001 0.001 0.001

0.001 0.001 0.001

20.00 20.00 19.95

20.00 20.00 19.95

20.96 20.99 20.99

21.06 21.06 21.06

19.55 19.50 19.50

1.285 1.286 1.289

FIG. 5 Schematic diagram of measurement system. Circled letters are the spreadsheet columns from Table 1: Ⓑ: Blower Voltage input, Ⓒ: Blower current input, Ⓔ: Input Voltage (
24), Ⓕ: Input Current (
1.25), Ⓖ: Control reactor surface K thermocouple, Ⓗ: insulated box air inlet temperature, Pt100 input, Ⓘ: insulated box air outlet 1 temperature, Pt100, Ⓙ: insulated box air outlet 2 temperature Pt100, Ⓚ: Active reactor temperature K thermocouple. Spreadsheet column D Pressure is not shown.

Air-flow calorimetry

119

A schematic is shown in Fig. 5. At the bottom left is the input power supply, a data logger (Graphtec, midi LOGGER GL 840), and a personal computer to record the data. Not shown here, a diaphragm vacuum gauge (MKS) was used to measure the pressure in the reactor. The reactor body temperature was measured at one point on the surface at the center of the body. The body temperature varies at different places on the surface. The center was selected to be conservative, because it is hotter than other parts of the body. The blower power supply, reactor-body power supply, and the data logger are all grounded at the same terminal. Fig. 6 shows the detailed piping that supplies internal exhaust and gas to the test reactor and the control reactor. Fig. 7 shows a conceptual diagram of the calorimetry. The reaction reactor and calibration heater are installed in similar positions in the insulated box. A fixed amount of air flows from the reactor inlet. The temperature at the inlet is measured with a platinum RTD, and the temperature at the outlet is measured with two RTDs.

Vacuum gauge

Control reactor

Test reactor

H2

Bulb: SS-4BK

Regulator, Nissan TANAKA B1-1NR-1G8G (25MPa >> 0.3MPa)

D2 Pump Vacuum pump ULVAC company G-101D (ODϕ27 ´ IDϕ20)

FIG. 6 Exhaust and gas supply piping inside the test and control reactors.

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Chapter 8 Experimental procedures for excess heat generation

FIG. 7 Conceptual diagram of thermal measurements.

Relationship between blower input and airflow velocity The blower is a sirocco blower that generates wind pressure, so the airflow coming from the blower is turbulent rather than laminar. Therefore, the temperature distribution of the air outlet is uniform. This is confirmed by theory and by measurements. Turbulence can be estimated from the following equation. The Reynolds number required to judge the boundary between laminar flow and turbulent flow is expressed by the following equation: Re ¼ ρUL=μ

(1)

where ρ is the density of the fluid [kg/m3], U is the representative flow velocity [m/s] (cross section average flow velocity), L is the representative length [m] (pipe inner diameter), and μ is the viscosity coefficient [Pas]. When the Reynolds number is larger than 2300, the flow is turbulent, and the flow is laminar when the number is lower. Specific values for these thresholds vary according to the literature, but the value of 2300 is often used as a guide. The expression for the Reynolds number gives the following rough indications about the flow. If the viscosity is high, the density is low, the flow velocity is slow, and the inner diameter is larger, laminar occurs easily. Conversely, if the viscosity is low, the density is high, the flow velocity is higher, and the inner diameter is smaller, turbulent flow is more likely. Here is test data applied to this equation: ρ is 1.165 kg/m3 at 30°C, U is a representative value of 5 m/s, the inner diameter of the tube is 0.05 m, μ is 1.8
105 m2/s. Therefore, the Reynolds number is about 18,000, which is much larger than 2300, so the flow is obviously turbulent. In other words, within the pipe from the air outlet, the flow velocity is likely to be nearly uniform. Measurements also confirmed the velocity was uniform. The wind velocity distribution at the outlet of the pipe 3 cm toward the side showed that when the blower input was 5 W, the flow velocity was the

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121

FIG. 8 Relationship between blower power and air velocity at the outlet for different locations of the anemometer across the tube section. The velocity profile is almost uniform.

same at both parts of the pipe, 4.8 m/s. Measurements taken 3 cm toward the top and bottom from the pipe center were also 4.8 m/s, showing that the wind velocity was uniform. Since the anemometer we used has 2-digit precision, a slight difference might be detected with a more precise anemometer. This uniform velocity indicates that the flow is turbulent. Fig. 8 gives an example of the blower input and airflow velocity. This velocity must be calibrated after opening and closing the box, moving equipment in the system, or cleaning the dust from the rotor of the blower. The blower input and wind velocity factors are very important to the calorimetry. The air flow rate is measured with a hot wire digital anemometer (CW-60, Custom Co., Ltd.). The flow of air through the box is confirmed by introducing smoke from the inlet into the box, and then timing how long the smoke takes to clear out. When measuring excess heat with the air-flow method, a pair of reactors are installed in the box: an active cell and a control cell. They are placed on insulating bricks to minimize heat loss through the table. These two reactors are of the same size and design. The control reactor is maintained at the same gas pressure and input power as the active test reactor. Depending on the sensor, the thermocouple and the RTDs often have different indicated values even when the temperature is the same. Therefore, the sensor readings need to be calibrated at several temperatures by placing them all in water with an alcohol thermometer as the standard. The platinum temperature sensor may be damaged if it is put into the water directly, so it is placed in a moisture-proof container. This calibration process requires several minutes for the temperature to stabilize. In the calibration liquid, the temperature may vary across the volume, so the liquid is stirred to make the temperature distribution uniform. The temperature of the air inlet and outlet is an important factor in the thermal calculations, so sufficient accuracy is required. RTD sensor readings tend to vary by 0.05–0.3°C. This error is within the expected range. The thermocouples are class 1 K types, with a tolerance of 0.4%, which is 1.5°C in

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Chapter 8 Experimental procedures for excess heat generation

the range of temperatures in these tests. In addition, when the K-type thermocouple is exposed to a temperature range from about 250°C to 550°C, the thermoelectromotive force of the exposed portion of the thermocouple increases gradually. When varying the length of the exposed portion, this phenomenon changed the readings to several degrees Celsius higher than the actual temperature. When the temperature exceeds 650°C, the thermocouple behavior recovers to its original state. This temperature range is reported variously in the literature. It is sharply evident when the exposed sensor length is different during the actual test and calibration. If the length for the actual test is not much shorter, then no problem arises. In short, thermocouples should be used with caution. RTDs are better than thermocouples for low temperature measurements, and offer high accuracy. The RTDs in this test were Pt100 Class A. The numerical value 100 means the resistance of the temperature-measuring element at 0°C is 100 Ω, with tolerance of  (0.15 + 0.002 jt j). The value t is the absolute value of the temperature. The error is 0.2°C when the air outlet temperature is 30°C. However, this instrument is unsuitable when rapid responsiveness is required and for the measurement of small areas, since the RTDs have a large volume, and they take longer than a thermocouple to reach thermal equilibrium. Reaching equilibrium takes about a minute. For the RTDs we use, with a thickness of 3.2 mm, the time needed to reach 90% of the equilibrium temperature in stirred water is 10 s. The larger the diameter of the temperature probe, the more time is needed for equilibration. Fig. 9 shows the relationship between the blower input and the average air speed at the blower outlet. This data was recorded at temperatures between 24.2°C and 24.9°C. The formula obtained from fitting the data in Fig. 9 is as follows: V=m=s ¼ y0 + A1
ð1  exp ðwb =t1 ÞÞ + A2
ð1  exp ðwb =t2 ÞÞ

(2)

The values of the constants are: y0: 3.42
1012, A1: 1.1013, t1: 0.00888, A2: 6.308, t2: 5.562. In this equation, wb is the power input to the blower.

FIG. 9 Blower input versus air flow velocity.

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123

Relationship between blower input and air outlet temperature Some of the data indicates that heat from the blower motor affects both outlet temperature sensors. Calibration with no input power to the reactors shows that when the blower power is stepped from 1.5 to 5 W, the outlet RTDs are 0.38°C warmer than the inlet sensors. This is a much larger temperature difference than could be produced by friction from the air moving through the box. Blowers are inefficient, so most of the input power to the blower is converted to waste heat in the motor. Most of this heat dissipates into the air above the box, but apparently some is conducted through the pipe to raise the temperature of the two outlet RTDs. To be conservative, all of the electric power input to the blower is measured, and all is included as heat input to the system (Fig. 10). The thermal measurements are calculated as follows. The specific heat of the constant-pressure air Cp is almost unaffected by the temperature and can be expressed by Eq. (3). The coefficients of the first and second terms of the equation are constants, and Tout is the temperature measured at the air outlet. These temperatures were measured continuously at both the air inlet and outlet. The influence of the coefficient is 1/10 of the measurement error described below, or less. Cp ¼ 0:987 + 0:0000661
Tout

(3)

The input Wtotal is calculated with Eq. (4). Wtotal ¼

XT

ΔWΔWb
Δt ¼ 0

Z

T

ðWt + Wb Þdt

(4)

0

where ΔW and ΔWb are the power input to the reactor and the blower during the measurements, and Δt is the sampling interval.

FIG. 10 Blower input power and temperature difference at the air outlet. These measurements were recorded with power only supplied to the blower, and no power supplied to the reactors. The increase in temperature of 0.38°C at 5 W input is attributed to heat from the blower motor (Fig. 11).

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Chapter 8 Experimental procedures for excess heat generation

FIG. 11 The amount of heat applied to the air outlet by the blower input.

The heat output Hout is calculated with Eq. (5). Hout ¼

XT

ΔV
S
ρ
Cp
Δt ¼ 0

Z

T

V
S
ρ
Cp
dTdt

(5)

0

Here, V is the wind velocity (m/s), S is the cross-sectional area of the air outlet (m2): 3.483
103, and ρ is the air density (kg/m3) which is expressed by Eq. (6). ρ ¼ 3:391
exp ðTout =201:26Þ + 0:41529

(6)

Here, V is the wind velocity measured from the anemometer, which is obtained experimentally and is expressed by Eq. (2), using the same constants. The 10 input data items input from the logger into the Excel spreadsheet columns B through K are listed in Table 1, above. Ten other columns, M through Y, are computed based on this data. These are shown in Table 2. In the equations here, the variable suffix n indicates the row number. Thus, column O blower power (Bn
Cn) means Column B
Column C for the row number n. The columns are: M. Correction for room temperature changes. The room temperature does not change significantly during the measurement time interval of 5 s. However, it changes by several degrees over the course of a day. The test should be performed at constant room temperature, but that is difficult in the building that houses our laboratory. The reactor-body thermal mass must also be considered in the correction term, because it takes some time to catch up to sudden changes in room temperature.

Table 2 Columns computed in Excel spreadsheet of logger data. M

N

deg C

Not used W

Correction for Room Temp. Change (Hn)(Hn 1)

O

Blower Input

P

Q

R

S

T

U

V

Pa

Win/W

deg C

J/deg C

m/s

kg/s

Not used Wout/W

Not Corrected used Wout/W

Pressure

Input Power

Tout-Tin

Hc/J

Blower Wind Speed

Air Weight

Output Power

Output Power Corrected

((In) + (Jn))
0.5-(Hn)(031
exp. ((On)/1.83))0.3755 + (Mn)

987 + 0.066
((In) + (Jn))
0.5

3.42
1010
(1exp((On)/ 0.00888) + 6.31
(1-exp((On)/ 5.562))

(Tn)
0.0035
(3.5
exp. ((((In) + (Jn))
0.5 + 273.2)/ 201.3) + 0.415)

(Rn)
(Sn)
(Un)

((Bn
Cn)- (Dn)
(Cn)2)/3 1330

(En
Fn)
60

W

X

Y

(Wn)/(0.98– 5.0811
(104
(Kn)))

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Chapter 8 Experimental procedures for excess heat generation

N. Not used. O. Input power to the blower, which is calculated from the values of columns B and C of Table 1. The value of 0.3333 is a coefficient to convert the current into the voltage recorded by the logger using a 3 Ω resistor for the current measurements. The next term, (Cn
Cn)/3, is the heat loss of the resistor used in this conversion, which is I2R ¼ (Cn/3)2
3 ¼ (Cn)2/3. The blower input in ðW Þ ¼ ðBn
Cn Þ
0:3333  ðCn
Cn Þ=3

(7)

P. Pressure of the reactor gas obtained from column D of Table 1; and 1330 is a conversion coefficient that is applied to the output voltage from the pressure gauge of the capacitance manometer. NP =Pa ¼ ðDn Þ
1330

(8)

Q. Input power to the reactor, calculated from the voltage and current values in columns E and F of Table 1. The coefficient of 60, set by the power supply, was obtained by multiplying the conversion coefficient for the current from the power supply with the voltage output: Win =W ¼ ðEn
Fn Þ
60

(9)

R. Temperatures calculated from columns H, I, and J of Table 1, and column M of this table. Columns I and J are the temperature at the air outlet. Two sensors are used, so this value is the average of the readings from both. Also, in the latter term of the expression (0.302
exp. ((On)/1.829)) 0.376 accounts for the change in air temperature coming out of the blower caused by waste heat and air friction from the blower. This value is calculated by the equation that fits the data plotted in Fig. 11. Furthermore, the term (Mn) is added to the calculation of the change in room temperature. This calculation is straightforward if the room temperature is constant, but when the room temperature fluctuates, the balance between room temperature and the reactor body temperature will change, requiring a correction. Again, equilibration takes time because of the large thermal mass of the reactor body. An accurate correction to any sudden change in room temperature must be made. When the change is several degrees over a day, the following correction is accurate. ðTout Tin Þ= deg ¼ ððIn Þ + ðJn ÞÞ
0:5  ðHN Þ  ð0:302
exp ððOn Þ=1:829ÞÞ  0:376 + ðMn Þ

(10)

S. The calculated constant-pressure specific heat of the air from Eq. (3), which can be calculated from the air temperature at the blower outlet in columns I and J of Table 1. Hc=J= deg ¼ 987 + 0:0661
ððIn Þ + ðJn ÞÞ
0:5

(11)

T. Wind velocity at the blower outlet. This value is obtained from the data in Fig. 10, and from the approximate calculation results in Column O. Since this calculation has an important effect on the accuracy of the test results, it is necessary to consider the uniformity of wind velocity inside the blower, the uniformity of the temperature distribution, the material and the shape of the pipe, and

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127

whether the pipe causes a stable flow of air at the outlet of the blower. The interaction of these factors means that calibration is important. V=m=s ¼ 1:544
1010 + 6:275
ð1  exp ððOn Þ=5:486ÞÞ + 1:091
ð1  exp ððOn Þ=0:00198ÞÞ

(12)

U. Volume of air obtained from column T, expressed as the weight of air. The coefficient shown next to the value in this column Tn ¼ 0.003483 (m2) is the cross-section area of the pipe. The next term is the product of the air density ρ in Eq. (6). It is obtained from the air outlet temperature in columns I and J and depends on temperature as follows: Air weight=kg=s ¼ ðTn Þ
0:003483
ð3:391
exp ððððIn Þ + ðJn ÞÞ
0:5 + 273:2Þ=201:26Þ + 0:41529Þ

(13)

V. Not used. W. Thermal energy from the air outlet. The output is obtained by multiplying columns R, S and U: Wout =W ¼ ðRn Þ
ðSn Þ
ðUn Þ

(14)

X. Not used. Y. Output power, taking into account the heat recovery rate. The equation for column W gives numerical values for each 5 s data interval. The total power of the inputs and the outputs is obtained by multiplying the sum of columns Q and W with accumulation interval t (5 s). The heat recovery varies with the reactor body temperature. This variation is measured with heat recovery tests conducted with the control reactor. The higher the temperature, the more heat escapes from the insulated box by radiation and conduction. The calculated heat generation is described in Eq. (15). This column, Y, lists the final heat generation value that is obtained by multiplying Wout (the W column) by the recovery rate. The denominator of Eq. (15), the heat recovery rate, is approximated from the control reactor test. Here, (Kn) is the reactor body temperature (in degrees Celsius). The coefficients are all values from the approximation: Wout =W ¼ ðWn Þ=ð5:76
exp ððKn Þ=1512Þ  4:78 + 0:00314
ðKn ÞÞ

(15)

Fig. 12 shows the heat loss from the walls of the insulated box, plotted against air temperature. This heat is not captured by the flow calorimetry. The horizontal axis gives the temperature difference between the air outlet and the inlet. The vertical axis shows the heat loss. This data was obtained from various types of control reactors, ranging in weight from 2 to 20 kg. The loss is proportional to the difference between the temperatures inside the box and room temperature. As the reactor temperature rises, the radiant heat becomes large, so it deviates from the linear relationship. When the temperature difference is small (0–5°C in Fig. 12), the heat loss is estimated to be 1 W/°C. Fig. 13 shows the heat loss from the walls plotted against the reactor temperature. The horizontal axis gives the control reactor temperature and the vertical axis is the amount of heat that escapes. The amount of lost heat increases almost linearly as the temperature increases, unlike Fig. 12. The correlation coefficient of the linear relation R2 shows a high correlation of 0.94.

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Chapter 8 Experimental procedures for excess heat generation

FIG. 12 Heat loss out of the walls of the insulated box versus the temperature difference between the air outlet and inlet.

FIG. 13 Relationship between the reactor body temperature during calibration and heat loss from the walls.

Since the reactor body temperature varies depending on the shape and weight of the control reactor, the reactor body temperature’s dependence on the heat recovery rate needs to be considered. Fig. 14 plots the reactor temperature against the heat recovery rate. When no power is supplied to the reactor, and the reactor temperature is 25°C (room temperature), the recovery rate should be close to 1. When the reactor temperature is 100°C, the recovery rate is 0.93; it is 0.82 at 300°C, and 0.78 at 360°C. The denominator of Eq. (15) is an approximate expression of the heat recovery rate measured by the control reactor.

Method 1: Plasma deposition

129

FIG. 14 Relationship between heat recovery rate and reactor temperature in control reactor.

We used two types of reactors: a cruciform-shaped reactor, and a cylindrical reactor. Fig. 14 shows the test results with these various control reactors. The independent variable is the temperature at the center of the control reactor, and the vertical axis gives the heat recovery rate. Regardless of the weight and shape of the control reactor, the trend is the same: if the control reactor temperature is around room temperature, the heat recovery rate is 1, but it decreases as the temperature rises. The heat recovery rate decreases to 0.9 at 200°C. The approximate equation that fits to the test values in the figure is O/I ¼ 5.76
exp. ( t/1512)  4.78 + 0.00314
t, where t is the temperature of the control reactor. O/I ¼ 0.127
exp. ( t/2.122
107) + 0.8541– 5.081
104
t. The approximate equation fitting these data is a linear approximation; O/I ¼ 0.98– 5.0811
104
t. The correlation coefficients R2 are high at 0.972 and 0.967. A linear approximation was used for the heat analysis. When the calibration data is recalculated to take into account the heat recovery rates in Fig. 14, the result shown in Fig. 15 is obtained. In this plot, the temperature of the control reactor is plotted on the horizontal axis and the output/input ratio is plotted on the vertical axis. The ▲ marks show data with no heat recovery-rate calibration applied, and the ● marks show the data after considering the heat recovery rate. The values are very close to O/I ¼ 1 after the correction for heat recovery.

Method 1: Plasma deposition Introduction In laboratories all over the world, excess heat has been generated from reactants made with various elements added to nickel. Most authors think that the system needs to be very clean to produce excess heat. Therefore, the goal of this project was to generate excess heat by reducing impurities. We used a cleaned nickel mesh reactant set in the inner surface of a stainless-steel reactor. After reducing

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Chapter 8 Experimental procedures for excess heat generation

FIG. 15 O/I ratio of calibration data considering the amount of heat loss and heat recovery rate (▲: before calibration of heat recovery rate, ●: after calibration).

impurities, we adhered palladium to the nickel, using two methods: Method 1, plasma deposition (described in this section) and Method 2, direct application (next section). Method 1 studies began with complicated water flow calorimetry. It was later changed to the simpler air-flow calorimetry described in Section “Air-flow calorimetry.” With Method 1, impurity gases in the nickel were removed by evacuation and heat treatment. High voltage was then applied to an electrode set in the reactor, so the surface of the nickel was bombarded with electrons and ions to further removes impurities from the surface of the nickel.

Reactor Fig. 16 shows the upper portion of the reactor (the lid) [15]. Three electrodes for heating and evaporating the metal-film base material are attached. Two of these electrodes are discharged at around room temperature, and the other is used at high temperatures (from 300°C to 650°C). For low-temperature operation, we use a noble metal (such as palladium or platinum fine wire) wound directly around the tip of the electrode. For high-temperature operation, metallic thin wires of noble metal are wrapped around the heater. The outside of the heater wire is covered with a ceramic such as alumina, and is used at around 800°C. In plasma film processing, such as the widely-used plasma vapor deposition method, ions of the noble metal are released from the positive electrode. In that case, both direct current and alternating current reactors have large electrode surface areas on the positive side. However, in order to use less of the noble metal, the temperature of the noble metal is increased to promote efficient deposition. Fig. 17 shows the discharge components of the reactor. In the photograph, the rectangular white component at the center is a high-temperature ceramic heater, which is 25 mm square and reaches 100°C when operated at 100 W. An R-type thermocouple is contained inside for temperature regulation (Sakaguchi Electric Co., Ltd.). A palladium wire 1000 mm long and 0.3 mm thick is wound

Method 1: Plasma deposition

Heater power High voltage

131

High voltage

Flange

Alumina insulation cover

Pd wire (1 mm × 100 mm) on Pd rod (2 mm × 200 mm)

Thermocouple in ceramic pipe

Pd wire wound ceramic heater

FIG. 16 Drawing of the lid and equipment attached to it.

around this heater. Another palladium rod (diameter 2 mm, length 250 mm) is used as the second discharge electrode and is shown on the right side of the heater in this photo. The top 200 mm of this electrode is covered with a ceramic insulating tube. Discharge emerges from the electrode tip. The palladium wire is heated with the heater, and a high voltage is applied to deposit palladium on the nickel mesh. Fig. 18 is a schematic of the reactor (height 500 mm, diameter 213 mm, volume 5.53 L, weight 50.5 kg). A 20-kg version of this reactor was also used. The reactor includes a central discharge electrode, a nickel mesh electrode, and a ceramic heater with palladium wire wound around it [15].

Reactants Nickel mesh and deuterium gas were used as reactants. The hydrogen molecules of the reactant are dissociated into hydrogen atoms and incorporated into the metal. The nickel mesh was plated with palladium (200 mesh, 200
300 mm, for 2 pieces with a total weight of 36g). When the palladium temperature exceeds 300°C, the hydrogen content cannot be increased further because hydrogen exits from the metal, but the metal is extremely active with hydrogen gas. As the temperature of nickel increases, the solubility of hydrogen gas into the metal increases, so excess heat generation at high temperatures becomes easier. To generate excess heat via cold fusion, surface refinement of the reactant metal, impurity removal, and surface modification with other metals are needed. An outline of these treatments is given below.

Activation The reactor is evacuated to 102 Pa at room temperature, to degas the metal and remove contaminants from it. The reactant metal is initially degassed and held at room temperature, because the formation of oxide film and nitride film are promoted by the in-system gas when it is processed at high temperature,

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Chapter 8 Experimental procedures for excess heat generation

FIG. 17 Photo of glow discharge electrodes and other parts.

making the subsequent activation treatment difficult. Hydrocarbon adheres to the reactant surface and must be removed as much as possible to reduce hydrogen activity. After impurities are removed by room temperature degassing, the metal is heated. When the metal is heated, the nickel surface is coated with palladium deposition by plasma discharge for 1–2 h. The metal is then cooled in the reactor for 1–2 h. The interior of the reactor is again evacuated to 102 Pa at room temperature. The time it takes to evacuate the reactor depends on the volume of the reactor and the pumping speed. When the pump speed is about 200 L/s and the maximum vacuum level is about 102 Pa it takes about 2 h. When there is a lot of residual gas, it takes longer. Evacuation must be thorough. To confirm the removal of impurities, the amounts of oxygen, nitrogen, water, and other substances in the

Method 1: Plasma deposition

133

FIG. 18 Schematic of the cruciform reactor (height 500 mm, diameter 213 mm, volume 5.53 L, weight 50.5 kg) 20-kg reactors of this design were also used in these tests, and to test the direct application method described in the next section.

evacuated gas should be measured by mass spectrometry. Even when the reactor is evacuated, some H2O gas, nitrogen, and oxygen remain. 70% of the residual gas is H2O, and the reactor is heated to 200° C to remove it. The evacuation process is continued until the Q-Mass component peaks for H2O [16– 18] are below the ion-current value for the Q-Mass of 109 A. After evacuation is complete, deuterium gas is supplied at several hundred Pascals. Next, the inner wall of the reactor and the reactant metal are heated up to 200°C by a heater coil wrapped around the reactor, which takes about an hour. The reactor body temperature is maintained at 200°C and the gas is evacuated, also over about 1 h. Immediately after evacuation ends, 100–200 kPa of deuterium gas is introduced while the temperature is kept at 200°C. While maintaining the temperature at 200°C, the reactor is evacuated again, and the process is repeated several times. Residual gas must be removed from the reactant metal and the reactor wall by the gas-cleaning process. If possible, a turbomolecular pump or other device with a high evacuation speed should be used. Next, the surface of the metal reactant is activated at 300°C with the gas pressure between 200 Pa and 1 kPa. Activation involves cleaning the surface thoroughly, while promoting deuterium absorption and desorption treatment to the reactant metal surface, which causes hydrogen embrittlement, making the metal surface rough. The deuterium absorption-release process is cycled. The temperature of the reactor is repeatedly raised from room temperature to 300°C and then cooled back down to room temperature in cycles that take about a day, since the heating time is 10–15 h and the cooling time is 4–6 h. This process should be repeated as many times as possible, but it should be applied at least five to six times in practice. This process is essential to produce excess heat.

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Chapter 8 Experimental procedures for excess heat generation

Plasma deposition process High DC and AC voltage is applied across the palladium rod and the fine electrode (+) at the center of the reactor and the nickel reactant (, ground) when performing plasma treatment on the surface of the reactant metal. The reactor D2 gas pressure is 50 Pa. If the gas pressure is much higher, at several hundred Pascals, then the plasma discharge will not start. About 0.5 kV is supplied from the highvoltage power supply, which can be high-voltage AC power. When discharging in the deuterium gas at 50 Pa, voltage from 500 to 1 kV between the center electrode and the reactant metal is applied so the current reaches 100–200 mA. Fig. 19 shows a photograph of the oscilloscope screen showing the current-voltage curve when 600 V is applied at AC frequency of 50 Hz. In the figure, the yellow dotted line shows zero voltage and the blue dotted line shows zero current. When the center electrode is positive, the current flows at 30 mA. No current flows in the negative direction. In addition, the AC voltage shown by the yellow line does not exceed 400 V and is almost flat. When the voltage decreases, the original AC waveform returns. The current shape does not show an exactly rectangular wave form, but it falls slightly in the periods when the voltage is flat. Thus, most of the discharge current is carried by electrons, and positive ions are slow, making no contribution to the charge transfer. Many electrons are present in the plasma, where they collide with other electrons and recombine with positive ions. However, by controlling the gas pressure, positive ions and electrons can be used to impact the reactant metal. In short, the electrode area must be controlled. In the electrode arrangement in the reactor we tested, the ratio of the areas of the cathode and the anode ranges from 10 to 100. During glow discharge, the voltage is concentrated near the cathode. Therefore, when the area of the cathode is large, electric current flows easily. When the cathode area is relatively small, very little current flows. From this, we can see that in order to deposit metal particles on the cathode, the anode area or the anode temperature must be increased.

FIG. 19 Changes in voltage and current during discharge processing.

Method 1: Plasma deposition

135

Plasma discharge description Current of about 20–50 mA per each 1 cm2 of palladium wire, and to a maximum of about 200 mA, flows overall. The plasma discharge should be maintained for 1 h and the process needs to be repeated around 10 times. During glow discharge, the metal surface is bombarded by electrons from the center electrode of the reactor. The reactant surface is covered with the electrode metal. In the case of the palladium electrode, direct current with voltage from 500 to 800 V is supplied to the palladium wire, and discharge is maintained for 1 h at current from 100 to 200 mA. The metal surface treatment is applied with this process and metal atoms of controlled fine particle size and distribution are adhered to the nickel reactant. The discharge is continued until the emission lines of water, nitrogen, and oxygen are negligible, which is an essential condition for excess heat generation. The residual gas is almost all deuterium. Fig. 20 shows a flow chart of the process for activation of the sample metal reactant.

Excess heat generation If the reactant metals are successfully activated, excess heat can be triggered by heating. When the temperature is raised to 200°C and D2 gas is inserted at 1 kPa, excess heat should be generated immediately. If it is not generated, the activation procedures described above must be repeated. When excess heat is generated, the amount of heat depends on the gas pressure, reactant weight, and the reactor temperature. When excess heat is generated, the temperature of the reactant goes higher than the control reactor temperature, sometimes by 50°C or more. As the reactant temperature rises, even if the amount of hydrogen in the reactor decreases, the excess heat reaches a certain equilibrium value. If the temperature is raised further, the excess heat increases. The level of heat from the nickel reactant depends on the temperature and can reach 50 W/g or more. The maximum attainable temperature depends on the state of the reactant, but we believe 850°C or more is possible. This temperature is a function of the heat resistance of the reactor and its components. Further, heat rate depends on amount of reactant and the dissipation rate of the heat. In principle, the heat value can be increased by increasing the reactant weight, covering the reactor body with heatinsulating material and raising the reactor temperature.

Metal sample

2: Heat in vacuum

1:Cleaning

3: Plasma discharge

Not enough Complete 6: Cooling in vacuum

FIG. 20 Activation treatment of the metal reactants.

5: Heat in vacuum

4: Heat in reactant gas

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Chapter 8 Experimental procedures for excess heat generation

Details of excess heat generation tests with various gas pressure, input power, and output/input ratios Plots of all test results appear in Figs. 21–25. These include the gas pressure (Fig. 21), input power to the reactor (Fig. 22), reactor temperature (Fig. 23), and O/I ratio (Fig. 24). The horizontal axis shows about 3 years of test time (110 million seconds; Ms) over which the same nickel reactants were left in the reactor.

FIG. 21 Changes in hydrogen pressure.

FIG. 22 Changes in input power.

Method 1: Plasma deposition

137

FIG. 23 Reactor surface temperature change due to input power over 3 years.

FIG. 24 Changes in O/I ratio over 3 years following the changes of set pressure and input power in Figs. 21 and 22.

Fig. 24 shows the ratio of output to input (O/I), which ranges from 0.5 to 2.5. During the initial activation, the O/I ratio is initially shown as less than unity. This is an artifact of the water-cooling calorimetry. The heat loss from the plastic box walls is not included in the calculation. After 51.3 Ms, the method of calorimetry was changed to air flow calorimetry, which allows higher cell temperatures. This produced more heat and it also eliminated the artifact. At 54.6 Ms, helium gas was introduced into the reactor. New D2 gas was introduced at 64 Ms. Air was introduced into the reactor at

138

Chapter 8 Experimental procedures for excess heat generation

FIG. 25 Changes in internal heater temperature and reactor body temperature (difference from room temperature) during initial processing.

92 Ms, and the reactant material was deactivated immediately. Excess heat decreased, and the output/ input ratio O/I dropped to 1.2. Fig. 25 shows the first 6-h test (23 thousand seconds; ks) during the measurement period shown in Figs. 21–24. This data was recorded at 10–30 Pa of vacuum and the nickel was heated using the internal ceramic heater. The maximum temperature of the heater (right axis) indicated with the red line reached 252°C. At that time, the thermocouple temperature on the side of the heater, indicated by the yellow line, was 220°C, which is lower than the temperature of the internal heater. Although the temperature of the nickel reactant was not measured, it was likely close to the temperature of the reactor body. The reactor body temperature (left axis) is expressed as the temperature difference: reactor temperature minus room temperature. The temperature of the internal nickel mesh was around 30°C. During the test with heat supplied by the internal heater, no excess heat is generated. After that, the nickel in the reactor was heated directly with an external heating coil that was wound around the reactor.

Control of reactor temperature and variation of the output/input ratio Fig. 26 shows the steps taken to change the reactor temperature and O/I ratio during the 370 days (32 million seconds; Ms) when heat input was supplied to the reactor. The overall test time was more than 3 years (1000 days; 100 million seconds; Ms). No heat was supplied for 725 days, so these days are not included in this graph. Even when the activation treatment was repeated 20 or 30 times at the beginning of the test, the O/I ratio rarely exceeded unity. When the ratio did exceed unity, it was difficult to prolong the reaction. After 2 Ms, the O/I ratio exceeded 1, indicating excess heat. In the initial stage of the test, the D2 gas pressure was from 100 to 200 Pa and the input power was 50 W. Close to the beginning of the test, at 10 Ms, the pressure increased to 1 kPa, but the input power remained the same at 20–50 W. After 22 Ms, the air flow method was adopted for the heat measurements. After 50 Ms, input power was increased

Method 1: Plasma deposition

139

FIG. 26 O/I ratio and reactor body temperature, during 725 days the reactor was heated (35 million seconds) over the total three-year test time (100 million seconds).

and the O/I ratio of excess power increased in response. As described above, at 28.4 Ms, air was introduced to the reactor, and the O/I ratio decreased immediately. (In Fig. 24, covering 3 years of real time, this event is shown at 92 Ms.)

Control of gas pressure Fig. 27 shows the gas pressure during the 370 days when heat input was supplied to the reactor. Pressure was 200 Pa up to 2 Ms and was then increased gradually after 4 Ms. Pressure was set to 1000 Pa at 7 Ms, and was once increased at 12 Ms to the maximum of 1700 Pa. The reactor was evacuated four times at around 13 Ms, as shown where pressure drops to 0 Pa. Even when it was evacuated, the hydrogen gas could not be completely removed from the reactant nickel. We increased the gas pressure again after 13 Ms and switched to the air flow measurement method at 22 Ms. Air was introduced into the reactor at 28.4 Ms, which reduced excess heat.

Change in temperature settings of reactor and internal heater Fig. 28 shows the internal ceramic heater temperature (open square) and the reactor temperature (black circle) during the 370 days when heat input was supplied to the reactor. Even when the internal heater temperature was raised to a very high temperature (700–800°C), the reactor body temperature was lower by about an order of magnitude (70–80°C). In the internal heater test, many tests were recorded in relatively short times, ranging from several thousand seconds to several hours. As shown in the figure, after 50 Ms, the reactor body temperature was increased, ranging from 100°C to 350°C. Since excess heat generation was found to depend on the reactor body temperature, the temperature was increased during the latter half of the experiment. The heating test was not continuous for the entire experiment. It was conducted in segments ranging from 24 h up to several weeks.

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Chapter 8 Experimental procedures for excess heat generation

2000

Gas pressure (Pa)

1500

1000

500

0 0

5

10

15 20 Time/Ms

25

30

35

FIG. 27 Gas pressure during 725 days the reactor was heated.

800 700

Temperature/°C

600 500 400 300 200 100 0 0

10

20

30

40

50 60 Time/Ms

70

80

90

100 110

FIG. 28 Temperature settings of internal heater (Open Square) and reactor (Black circle), during 725 days the reactor was heated.

Method 1: Plasma deposition

141

Input time indication of output/input ratio change Fig. 29 shows the O/I ratio recorded while varying the heater input and gas pressure. After the measurement method was changed at 21 Ms, the O/I ratio approaches twice its maximum. In the first half of the experiment before 21 Ms, the cooling water circulation method was used, and the O/I ratio was low because the reactor body temperature was low.

Excess heat example An example of a test that generated excess heat is described below. After activation, with input electric energy of several hundred watts, the output thermal energy reaches more than double the input energy, as shown in Fig. 29. Excess heat production is an exponential function of temperature, as explained below. At a temperature of 300°C, the maximum energy that we observed was 0.6 kW. The output also follows an exponential function of absolute temperature [15, 16]. The reactant used in these tests was nickel, and the reaction gas was hydrogen or deuterium. The deuterium molecules dissociated into deuterium atoms and were incorporated into the metal. Nickel is active against hydrogen, and the higher the temperature, the greater the solubility of hydrogen, which makes heat generation easier. Surface refinement treatment of the reactant metal, impurity removal activation, and surface modification treatment with other metals are needed for heat generation. When a reactive metal sample is treated and kept at high a temperature in hydrogen gas, the hydrogen molecule dissociates to atomic hydrogen on the metal surface, increasing the amount of hydrogen atoms available. The presence of this atomic hydrogen is necessary for excess heat generation. This produces 50 W/g, which is 1–10 W/cm2 per area.

3

O/I

2

1

0 0

FIG. 29 Change in output/input ratio.

5

10

15 20 Time/Ms

25

30

35

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Chapter 8 Experimental procedures for excess heat generation

In the initial stage of the example shown here, since the activation process is in progress, the O/I ratio often does not reach unity, and even if it exceeds unity, the quantity of generated heat is small. However, the O/I ratio exceeds two in some cases. Fig. 30 shows the change in power output when 100 W was input to the reactor during excess heat generation. The excess heat was generated continuously, and the output power increased to 180 W. The input power was discontinued at 82 ks. The input heat was 100 W
82.5 ks ¼ 82.5 MJ, and the output heat was estimated to be 151.88 MJ; thus, the output/input ratio was 1.841. The reaction stopped because the heating was stopped at 83 ks, but if it had continued, excess heat generation would probably continue for as long as hydrogen gas is present. Calibration tests with the control reactor were performed at three levels of input power. Fig. 31 shows the output power of the control reactor with the inputs of 80, 120, and 248 W. The output power is confirmed to be the same as input power in all cases. The output increases from zero and becomes constant after the reactor vessel reaches its terminal temperature. The reactor has a large thermal mass, so this takes some time. The results with the same inputs to the test reactor during excess heat generation are shown in Fig. 32. These tests behave differently from the calibration tests. The heat output increases over time. For example, 248 W input was applied over 22 ks, and the power output reaches 480 W and the Out/In ratio reaches 1.953. The relationship between excess power (Wex) and reactor temperature is plotted in Fig. 33. The excess power increases as the temperature of the reactor increases. For example, the excess power is 100 W at 100°C, 315 W at 200°C, and 480 W at 250°C. Excess power of 10 and 20 W was generated even when the reactor was near room temperature. The temperatures shown here are at equilibrium. The temperature of the nickel in the reactor is not uniform. This data was taken at a representative point on the outer wall of the reactor. 250 W in/W W out/W

Input/W and output/W

200

150

100

50

0 0

2

4

6 Time/10ks

FIG. 30 Changes in input and output power with treated reactants and 100 W input.

8

10

Method 1: Plasma deposition

143

500

400

Power/W

248 W input 248 W output

300

200 120 W output

120 W input 100

80 W output

80 W input 0 0

10000

20000

30000

Time/s

FIG. 31 Calibration data for inputs of 80, 120W, and 248 W.

500 248 W output

Power/W

400 120 W output

248 W input

300

120 W input

200 100

80 W output

80 W input

0 0

10000

20000

30000

Time/s FIG. 32 Examples of excess heat generation with 80, 120, and 248 W input.

Fig. 34 shows the relationship between the reactor temperature and excess heat for the data in Fig. 33, but it plots the value of excess heat divided by sample weight against the reciprocal of the absolute temperature. This is an Arrhenius plot, a type often used to describe chemical reaction rates. At higher temperatures, the excess heat increases, and can be expressed with an exponential function.

144

Chapter 8 Experimental procedures for excess heat generation

600

Excess W

400

200

0 0

100

200 Reactor temperature (°C)

300

400

FIG. 33 Relation between reactor body temperature and excess heat.

100

Excess heat (W/g)

10

1

0.1

0.01 0.001

0.002

0.003

0.004

1/T

FIG. 34 Arrhenius plot of excess heat against reactor temperature.

This expression of the data is useful for estimating the reaction mechanism. It yields an approximation of the theoretical reaction activation energy. When the temperature of the reactor (Tr) is expressed as the reciprocal of the absolute temperature, as shown in Fig. 34, the excess heat shows a linear relationship. We speculate that the excess heat would reach the order of kilowatts at 1/Tr ¼ 0.001, i.e.,

Method 2: Direct deposition

145

approximately 700°C. Excess heat increases exponentially with the reactor temperature. The reaction activation energy Ea was calculated from the linear region between 100°C and 523°C in Fig. 34 to be 0.165 eV/K/atom.

Method 2: Direct deposition Introduction There exists a wall of irreproducibility in most of today’s research on cold fusion. Since the experiments tend not to be reproducible, the mechanism behind the occasional observations of cold fusion remains unclear. We have developed 10 different methods to produce cold fusion reactions over 30 years of research. The method for excess heat generation described in Section “Method 1: Plasma deposition” was devised with a great deal of trial and error. A simpler and faster method of direct application was derived from the complex method. This method was developed recently and can be improved in many ways. All of the tests with this method employed the air flow calorimetry described in Section “Air-flow calorimetry.”

Material Palladium is plated onto a nickel screen. Two methods are used. The first is to rub the nickel screen with a palladium rod. The entire surface is rubbed on both sides. The second method is to deposit a palladium film on the nickel mesh surface by plating with an electroless plating solution of Pd-10 (High Purity Chemical Co., Ltd.), with palladium concentration of 10 g/L. The plating conditions were: 40–60°C, pH 1.5. Fig. 35 shows a photograph of the nickel meshes. Each is 20
30 cm, 180 mesh, and weighs 13 g. We used all three meshes in all tests. They were rolled up together and placed in the reactor. The nickel preparation steps are as follows. First the mesh is cleaned: 1. Wash with a mild detergent in ordinary tap water, and scrub with a plastic dish washing pad.

FIG. 35 Nickel-net reactant with palladium metal attached, 20 cm
30 cm, 180 mesh, total weight 40 g.

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Chapter 8 Experimental procedures for excess heat generation

2. Sand with water resistant sandpaper, starting with 250 grit, then 400, then 1000. Wash with mild detergent and rinse with tap water. 3. Soak in tap water at about 90°C for 1 h. 4. Wash with alcohol. This process removes oil and roughens the metal surface. After cleaning: 1. The mesh is placed in reactor. Vacuum evacuation to 102 Pa at room temperature, for about 2 h. 2. Heat pretreatment: removal of impurities and surface refinement of the metal surface. The temperature is raised to 100–120°C, for 5–20 h. 3. Mesh is removed from reactor. At this stage the surface should be free of contaminants. Coat palladium onto nickel, with rubbing or electroless deposition plating. 4. Mesh is placed in reactor again. Heat for 1–2 h. 5. Cool down in the reactor, 1–2 h. Steps 4 and 5 may need to be repeated a few times. Examples of the reactors we used are shown in Figs. 36–39. Although any reactor can be used, two of the small R14 and R19 types (Fig. 36) are more convenient. This reactor has a simpler structure and smaller size than the large reactor used in the test described in Section “Method 1: Plasma deposition.” The length of the reactor body is 300 mm, the diameter is 40 mm, and the weight is 2 kg. Every reactor has valves for vacuum evacuation and gas supply. A spare high-voltage connection is included. No discharge was performed in these reactors, so the reactor did not have a window, unlike previous models. All reactors were wrapped with a heater wire. The heat input was 100 V or 500 W. The maximum heating temperature reached 350°C.

Results Table 3 shows the test results with the corrected heat recovery rate using the process described above.

FIG. 36 Reactor R14 and R19 type small reactor, length 340 mm, diameter 70 mm, weight 2 kg.

Method 2: Direct deposition

FIG. 37 R15 test reactor, length 500 mm, diameter 120 mm, weight, 20 kg.

FIG. 38 R6 test reactor, length 500 mm, diameter 120 mm, weight, 20 kg.

FIG. 39 R7, R18 test reactor, cruciform type, horizontal length 500 mm, vertical length 400 mm, weight 22 kg.

147

148

Chapter 8 Experimental procedures for excess heat generation

Fig. 40 shows the O/I ratio for the reactor temperatures in the excess heat test results shown in Table 3. In Fig. 40, the open circle marks indicate data before correction for the heat recovery rate, and black circle marks are the data after this correction. As can be seen in Table 3, the O/I ratios of the R7 and R18 reactor test results were small. This reactor is the cruciform type, and the heat generation was small because of the activation process and the arrangement of the reactants. Fig. 41 shows how the O/I ratio depends on the deuterium pressure in the excess heat tests described in Table 3. The correlation coefficient R2 is 0.73. Although there is correlation, the inputs varied and the shape of the reactor was different, no clear conclusion can be drawn. More analysis is needed. Fig. 42 plots the value of excess heat (Wex) per gram of the sample against the reactor temperature. The temperature dependence of the excess heat generation per mass of the reactant Wex/g shows a high correlation coefficient R2 ¼ 0.883.

Table 3 Results of new method excess heat generation test. Pa

Watt

°C

Ratio

Watt

Wec/R

Wex/r

Ratio

Reactor

Pressure

Input

Reactor Temp.

Out/In

Wex

W/g

W/g

O/I, Before

R14 R14 R14 R14 R14 R14 R15 R6 R7 R7 R7 R18 R7 R19 R19 R19 R19 R19 R19 R19 R19 R19

1100 1100 2000 2200 2200 2200 950 900 400 400 420 900 850 5412 6320 5949 5421 600 120 78.4 46.27 35.27

49.5 99.6 29.5 49.5 79.7 10.4 100.0 100.0 100.0 200.0 200.0 100.0 100.0 100.0 197.4 50.1 99.3 98.6 98.2 98.0 98.0 97.9

176.50 267.80 117.90 167.30 228.30 62.20 129.40 80.90 94.80 157.00 145.00 106.35 86.30 238.90 386.00 145.00 234.00 229.00 232.00 232.70 232.60 232.00

1.12 1.26 1.24 1.27 1.29 1.21 1.25 1.25 1.12 1.16 1.12 1.12 1.15 1.39 1.40 1.21 1.42 1.42 1.40 1.43 1.41 1.42

4.98 25.50 7.13 13.25 22.71 2.23 25.20 24.69 12.21 31.86 22.82 12.25 14.63 38.63 78.31 10.42 41.84 41.06 39.64 42.30 40.46 40.89

0.00249 0.01275 0.00357 0.00662 0.01136 0.00112 0.00140 0.00123 0.00056 0.00145 0.00104 0.00056 0.00066 0.02972 0.06024 0.00801 0.03219 0.03159 0.03049 0.03254 0.03113 0.03146

0.1383 0.7084 0.1982 0.3679 0.6308 0.0620 0.6999 0.4572 0.3393 0.8851 0.6339 0.3403 0.4064 0.7154 1.4501 0.1929 0.7749 0.7604 0.7340 0.7834 0.7493 0.7573

1.00 1.06 1.14 1.15 1.11 1.15 1.15 1.17 1.05 1.04 1.02 1.10 1.06 1.15 1.06 1.08 1.20 1.20 1.19 1.21 1.19 1.20

Method 2: Direct deposition

149

1.6 1.5

Out/In

1.4 1.3 1.2 1.1 1.0 0.9 0

100

200 300 Reactor temperature (°C)

400

500

FIG. 40 Results of excess heat test. Open circles indicate data before the recovery rate was considered. Black circles indicate data after accounting for the recovery rate. 1.5

Out/In ratio

1.4

1.3

1.2

1.1

1.0 0

2000 4000 D2 gas pressure/Pa

6000

FIG. 41 Excess heat versus deuterium pressure, R2 ¼ 0.73.

The two-dimensional relationship between the excess heat generated per gram of reactant and the deuterium pressure at various reactor temperatures is shown with the color graph in Fig. 43. Here, the excess heat value is indicated by the legend to the right of the graph, increasing as it

150

Chapter 8 Experimental procedures for excess heat generation

2.0 1.8 1.6

Wex/g (W/g)

1.4 1.2 1.0 0.8 0.6 0.4 0.2 0.0 0

100

200 300 Reactor temperature (°C)

400

500

FIG. 42 Temperature dependence of excess heat generation per unit sample weight Wex/g, R2 ¼ 0.883. Excess Watt per reactant weight (W/g)

5000

1.6 1.4 1.2 1.0 0.80 0.60 0.40 0.20 0.060

Pressure (Pa)

4000

3000

2000

1000

0 0

50

100

150 200 250 300 Reactor temperature (∞C)

350

400

FIG. 43 Excess heat per gram of sample weight plotted with temperature and pressure.

changes from blue to red. Although the color changes obviously along with the temperature change in the horizontal axis direction, no change in color is observed with different pressures shown on the vertical axis. The graph clearly shows that excess heat depends on temperature, but it is inconclusive about the effects of pressure.

Method 2: Direct deposition

151

Temperature dependence for excesses heat generation Excess heat generation is mainly determined by the temperature in the reactor. Fig. 44 plots the data from Table 3. The relationship between the reciprocal of the reactor absolute temperature (1/T) and the logarithmic value of the excess heat per unit weight of the reactant is shown. These values were recorded with various types of reactors, and a clear temperature dependence appears. From Fig. 44, the activation energy is calculated as 0.166 eV/atom ¼ 0.636
1023 kcal/atom ¼ 3.83 kcal/mol. The correlation coefficient R2 takes a large value of 0.942 and when the temperature is infinite, that is 1/T ¼ 0, the excess power at W0 is estimated as 52.6 W/g. Fig. 45 (Fig. 34), shown again here for the sake of comparison. It shows excess heat generation per unit of reactant weight with activation by plasma deposition. The activation energy is estimated as 0.193 eV/atom. This data is plotted for the 3 years of the previous test, including tests in which the reactants were not sufficiently activated. The correlation coefficient R2 ¼ 0.611, the activation energy 0.193 eV/atom when the temperature is infinite, and W0 is estimated as 845.2 W/g. Fig. 46 shows selected values from the data in Fig. 45. That is, values where the material was fully activated, from 21.03 Ms to 21.36 Ms in Fig. 29. In Fig. 46, the activation energy is 0.165 eV/atom. The correlation coefficient R2 is 0.96, which is very high. When the temperature is infinite, that is at 1/T ¼ 0, W0 is estimated to be 1171.3 W/g. A linear relationship appears in the Arrhenius plot of 1/T of excess heat generation. The activation energy was 0.166 eV/atom ¼  0.636
1023 kcal/atom ¼  3.83 kcal/mol, as calculated from the test results so far. This activation energy is very close to 0.17 eV/atom, which is the heat at which hydrogen dissolves into nickel. Since the diffusion activation energy in nickel [17] is 28.6 kJ/mol, that is 6.875 kcal/mol, it is 0.298 eV/atom. The excess-heat activation energy is about 1.8 times larger than this value. In other words, the amount of hydrogen dissolved in nickel is likely to be important for excess heat generation. 10

Excess Watt (W/g)

1

0.1

0.01

1E-3 0.000

0.001

0.002 1/T (K–1)

0.003

0.004

FIG. 44 Amount of excess heat versus the inverse temperature, with reactant formed by direct deposition. This is an Arrhenius plot, R2 ¼ 0.942. At 1/T ¼ 0 excess power density of W 0 is estimated as 52.6 W/g.

152

Chapter 8 Experimental procedures for excess heat generation

100

Excess Watt (W/g)

10

1

0.1

0.01 0.001

0.002

0.003

0.004

1/T

FIG. 45 Correlation coefficient R2 ¼ 0.611, slope ¼ 0.193 eV/atom, W 0  845.2 W/g.

100

Wex (W/g)

10

1

0.1

0.01 0.001

0.003

0.002

0.004

1/T (K–1)

FIG. 46 Values after activation from 21.03 to 21.36 Ms from Fig. 24 are shown. R2 ¼ 0.96, W 0 is estimated as 1171.3 W/g.

W0, the excess heat of Wex/r at 1/T ¼ 0, changes from 52.6 W/g to 1171 W/g as the temperature increases to the maximum. This large value is likely due to the difference in the activation of the sample or the difference in the size of the portion of the reactant sample where the excess heat is generated occurs. In the data of the amount of excess heat generation, the sample weight was

Summary

153

36 g, and the smaller amount of excess heat was generated from a sample with weight of 56 g. If we assume that the excess heat is generated from the whole reactant, the smaller W0 is 2.946 kW, and the larger W0 is 42.156 kW. This result suggests that an extremely large value of W0 may be generated if all the reactant is activated.

Summary The reactant activation method described in Section “Method 1: Plasma deposition” is effective for generating excess heat. However, the process of activation is time-consuming, complicated, and cumbersome. With direct application of palladium to the nickel reactant surface, excess heat is more likely to be observed, although at a lower rate. The generation of excess heat is difficult when nickel alone is used as the reactant. Excess heat is more likely when palladium is plated onto the nickel surface. The amount of excess heat generation increases exponentially with temperature. For this reason, the reactor can be controlled by varying the temperature. Excess heat can be generated with hydrogen or deuterium used as the reactant gas. The amount of excess heat is not affected by the pressure of the reactant gas in either case. Excess heat generation is also possible with only a small amount of hydrogen in the reactor. Since some amount of H2O is present even in a vacuum, we presume that excess heat is possible even in vacuum conditions. A linear relationship is shown in the Arrhenius plot of excess heat generation against 1/T. From this relationship, the activation energy was estimated as 0.166eV/atom¼  0.636
1023 kcal/atom ¼ 3.83 kcal/mol [15, 16]. This value is close to 0.17 eV/atom, which is the heat of hydrogen dissolution into nickel. The hydrogen-diffusion activation energy in nickel is known to be 28.6 kJ/mol, that is, 6.875kcal/mol ¼  0.298eV/atom [17]. This value is 1.8 times greater than that obtained in our test. From this fact, we surmise that excess heat generation is caused by the dissolution of hydrogen into nickel and not diffusion. In particular, we surmise that the amount of hydrogen dissolution is a deciding factor in the occurrence of the cold fusion reaction. On the other hand, the amount of excess heat does not depend on deuterium pressure within the range of pressures we tested. The solubility of hydrogen in nickel is small at pressures of 1 atm or less, and Sieverts law is given in the following formula; the concentration of hydrogen in nickel is proportional to the square root of pressure [18] in this pressure region. √P=P0 ¼ Ks x

Here, P is calculated as pressure (Pascals) with P0 as 1 atm. The variable x is the concentration. Ks is the Sievert constant, and can be calculated with the following equation. LnðKs Þ ¼ ΔSs=R + ΔHs=RT

In this equation, ΔSs is the entropy of dissolution, ΔHs (kJ/mol) is the dissolution energy. In the case of nickel, ΔSs/R (mol H) is 6 mol H and ΔHs is 16 kJ/mol (temperature range is from 350°C to 1400°C) [19]. The value of 16 kJ/mol is perfectly consistent with the reaction activation energy that we observed, since 3.83 kcal/mol ¼  16.0 kJ/mol. The solubility of hydrogen in a 0.14 mm thick foil of nickel with purity of 99.5% is predicted by the following empirical formula (from Ref. [20]) that is applicable in the temperature range from 400°C to 600°C and the pressure range from 0.133 to 240 Pa.

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Chapter 8 Experimental procedures for excess heat generation

log ðSsÞ ¼ 1:732 + 0:5logðPÞ  645=T The dissolution energy ΔHs is  24:7kJ=mol:

Fig. 47 shows a plot of hydrogen solubility at 105 Pa in nickel against the inverse of the absolute temperature. At the melting point of nickel, 1455°C, the solubility increases about 2.27 times and it increases further as the temperature continues to rise. If the reactant activation estimated here is accurate, the data in Fig. 46 imply that the amount of excess heat would be 70 W/g at 700°C. Of course, this value is an extension of the data obtained from the test results and cannot be confirmed unless the test is performed at this temperature. The temperature of 700°C is close to the upper temperature limit of the reactor, and the heat resistance of the material will have to be tested before such tests are attempted. This test shows that the amount of excess heat generation is less dependent on deuterium pressure than it is on temperature. This result is understandable because the solubility of hydrogen in nickel is proportional to the square root of pressure, while the temperature dependence is an exponential function of absolute temperature. The following overall conclusions can be drawn from the test results. For the creation of a large amount of excess heat, the solubility of hydrogen in the metal is an important factor. This factor means that the dissolution energy is 50 kJ/mol and the dissolution entropy is a few mol H, which implies that practically all the reaction that causes excess heat generation occurs inside the metal. If enough hydrogen or deuterium can penetrate the metal, the reaction will occur. The reaction can occur with hydrogen or deuterium as reactants. If this condition of hydrogen dissolution is satisfied, it may be that a wide variety of metals and alloys can be used for the reaction.

1000

Solubility/cc/100 g

100

10

1

0.1

0

0.0005

0.001

0.0015 1/T

FIG. 47 Hydrogen solubility in nickel versus inverse temperature.

0.002

0.0025

0.003

References

155

Finally, tunnel fusion reactions, which proceed very slowly, are a good candidate explanation for the mechanism behind excess heat generation. We are working to understand this mechanism better, and look forward to publishing further experiments that reveal its details.

Acknowledgments I would like to express special thanks to David Nagel for his kind review of this manuscript. I also thank Dewey Weaver for his support. On September 6, 2018, a large earthquake struck Sapporo, where my laboratory is located. Despite previous precautions, some of my equipment was damaged. I feared I would not be able to continue this research. But, fortunately friends and fellow researchers from around the world contributed to a GoFundMe initiative that allowed me to continue this work. I thank them all.

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[16] T. Mizuno, H. Yoshino, Confirmation of excess heat generation during metal-hydrogen reaction, in: Proc. JCF16, Kyoto Japan Dec. 11-15, 2015, pp. 16–27. [17] E. Johnson, T. Hill, The diffusivity of hydrogen in nickel, Acta Metallugica. 3 (9) (1955) 566–571. [18] A. Sieverts, W. Danz, Die L€oslichkeit von Deuterium in festem Nickel, Zeit. Anorg. Chem. 247 (65) (1941). [19] E. Fromm, E. Gebhardt (Eds.), Gase und Kohlenstoff in Metallen, Reine und Angewande Metllkunde in Einzeldarstellungen, Band 26, Springer-Verlag Berlin, Heidelberg New York, 1976 622. [20] M. Armbraster, The solubility of hydrogen at low pressure in iron, nickel and certain steels at 400 to 600°, J. American Chem. Soc. 65 (6) (1943) 1043–1054.