- Email: [email protected]
01488 Thermogravimetric analysis of the co-combustion of coal and sewage sludge
10 Engines (power generation and propulsion, electrical vehicles) h, with a maximum mixing combustion ration of 18%. It provide the metallurgy enterprises with a new technique to harness the low heating value exhaust gas.
04•01488 Thermogravimetric analysis of the co-combustion of coal and sewage sludge Bel6n Folgueras, M. et al. Fuel, 2003, 82, (15 17), 2051-2055. Combustion of three different sewage sludge samples (B, F and S), one bituminous coal and sludge-coal blends were studied by TG dynamic runs carried out at 10°C/rain in the temperature range 25-800°C. The sludge is mainly formed by two organic fractions with different reactivity; the less reactive fraction decomposes and burns at temperatures closer to those of coal, although, in general, slightly lower. For coal-sludge blends, no interactions between the components were detected. The Arrhenius kinetic parameters were calculated from the experimental results, considering the process as a series of consecutive first order reactions. Coal reactivity is scarcely modified as a consequence of a low addition of sludge (10 wt% blends). The 50 wt% blends show two different regions of reactivity. In the lower temperature region (about T < 350°C), the blend reactivity is similar to that of sludge, while in the higher temperature region ( T > 350°C), it is similar to that of coal.
l0
ENGINES Power generation and propulsion, electrical vehicles
well as thrifty energy housekeeping and early detection of possible restrictions of reliability by battery monitoring are necessary functions. To meet today's requirements for battery monitoring and energy management, solutions have been developed for series vehicles launched in years 2001-2003, operating at the 14 V level.
04/01492 Comparative analysis on the part load performance of combined cycle plants considering design performance and power control strategy Kim, T. S. Energy, 2004, 29, (1), 71 85. The purpose of this study was to analyse the relationship between the part load performance and design performance of gas turbines and combined cycle plants. The effect of power control strategy on the part load performance of the combined cycle was also examined. The analysis was carried out using a proven cycle simulation program. Based upon the design performances of actual gas turbines, a consistent principle of design point selection was applied to four different gas turbines representing various technology levels. Tile part load control strategies considered were fuel-only control and IGV control. It h a s been observed that gas turbines with higher design performances exhibit superior part load performances. Since the average combined cycle performance is affected by the range of IGV control, as well as its temperature control principle, a control strategy appropriate for the load characteristics of the individual plant should be adopted.
04/01493 Detergent additives for reduced power loss and power recovery in diesel engines Davenport, J. N. et al. PCT Int. Appl. WO 03 44 134 (CI. C10L1/22), 30 May 2003, GB Appl. 2001/27953. Diesel fuel with reduced engine power losses and reduced smoke or particulate emissions, especially synthetic low-sulfur Fischer-Tropschderived diesel (e.g. by the Shell Middle Distillate Synthesis process), contains 100-500 weight ppm of a detergent. The fuels are evaluated based on a comparison of engine power losses and power recovery after testing the engine on different fuels in successive driving cycles.
04•01489 Actions to promote energy-efficient electric motor repair
04/01494 Development of an autoignition submodel for natural gas engines
de Almeida, A. T. and Ferreira, J. T. E. International Journal of Energy Technology and Policy, 2003, 1, (3), 302-314. Electric motors are repaired 2-3 times over their lifetime. Poor repair practices, particularly widespread in developing countries, can lead to a significant increase in motor losses. It is estimated that worldwide poor repair leads to annual electricity losses of approximately 40 TWb, representing 20 Mtons of CO2 emissions. The main objective of this paper is to provide a technical basis for designing demand side management actions, which address the motor repair market. This paper brings into focus motor repair process trends, energy-efficient motors, typical repair process, actions to promote energy-efficient motor repair, energy-efficient motor rebate schemes to replace old, badly damaged motors and the factors influencing payback. This paper will be useful to energy policy makers, and Demand Side Management (DSM) staff in energy agencies and electric utilities.
Soylu, S. and Van Gerpen, J. Fuel, 2003, 82, (14), 1699-1707. This paper describes a new auto-ignition sub-model for engine modelling codes. This sub-model does not require extensive computational resources and is easily portable to various computational environments. It also considers variation of natural gas composition due to propane addition. Computation results show that the knock occurrence crank angle can be predicted within 2 ° CA when the model is coupled to a zero-dimensional engine model, which was also developed for the present work. The results with the model incorporated into a multi-dimensional model (KIVA) are also promising. KIVA was able to predict if the engine was going to knock or not and also gave correct trends in the knock intensity.
04/01490 Analysis of endgas temperature fluctuations in an si engine by laser-induced fluorescence Schief31, R. and Maas, U. Combustion andFlame, 2003, 133, (1-2), 1927. Spatial temperature fluctuations in the unburned endgas of a sparkignited (SI) engine were investigated. The approach of the study exploits the fact that the quantities (species concentrations, temperature) comprising the state of the combustion chamber gases are not independent, but often correlate sharply. Information about spatial temperature variations is obtained indirectly by observing two complementary quantities that sensitively reflect the local temperature. Spatial formaldehyde (H2CO) concentration variations in the endgas are converted to temperature fluctuations using calculated correlations between temperature and [H2CO]. Additionally, the geometrical size of inhomogeneities is deduced from LIF-images displaying the locally varying formation of temperature-sensitive intermediate species. The results indicate that temperature fluctuations exceeding 20 K are present in the nominally homogeneous endgas. The geometrical size of these fluctuations ranges from ,-~1 mm to ,-~I cm.
04/01491 Battery monitoring and electrical energy management Meissner, E. and Richter, G. Journal o f Power Sources, 2003, 116, (12), 79-98. New vehicle electric systems are promoted by the needs of fuel economy and ecology as well as by new functions for the improvement of safety and comfort, reliability, and tile availability of the vehicle. Electrically controlled and powered systems for braking, steering and stabilization need a reliable supply of electrical energy. The planned generation of electrical energy, the provision of adequate storage, as
04•01495 Ecological optimization for generalized irreversible Carnot engines Chen, L. et al. Applied Energy, 2004, 77, (3), 327-338. The optimal ecological performance of a Newton's law generalized irreversible Carnot engine with losses due to heat-resistance, heat leak and internal irreversibility is derived by taking an ecological optimization criterion as the objective. This consists of maximizing a function representing the best compromise between the power and entropy production rate of the heat engine. A numerical example is given to show the effects of heat leakage and internal irreversibility on the optimal performance of the generalized irreversible heat-engine.
04/01496 Emission characteristics of diesel engine operating on rapeseed methyl ester Nwafor, O. M. I. Renewable Energy, 2004, 29, (1), 119-129. Biofuels are being investigated as potential substitutes for current high pollutant fuels obtained from the conventional sources. In the past, fuels were generally selected on the basis of lowest cost relating to the requirements of the engine, and no attention was given to the possible effects of their use on the environment. Recent concerns over the environment, increasing liquid fuel prices and scarcity of supply in the last decade have promoted interest in the development of alternative sources of liquid energy. The purpose of this research was to evaluate the potential of rapeseed methyl ester (RME) as a liquid fuel for diesel engines in relation to meeting emission requirements. The test results showed that RME and its blends with diesel fuel emitted high CO2 compared to test results on diesel fuel. A significant reduction in emissions of hydrocarbon (HC) was recorded when running on RME and the blends. HC emissions were noted to increase with increased amount of diesel fuel in the blend. The fuel economy was a little worse when running on R M E due to its low energy content. There were no marked difference noted for the exhaust temperatures of the blends, RME and diesel fuel at high-speed operation. However, the diesel fuel
Fuel and Energy Abstracts May 2004 203
04•01488 Thermogravimetric analysis of the co-combustion of coal and sewage sludge Bel6n Folgueras, M. et al. Fuel, 2003, 82, (15 17), 2051-2055. Combustion of three different sewage sludge samples (B, F and S), one bituminous coal and sludge-coal blends were studied by TG dynamic runs carried out at 10°C/rain in the temperature range 25-800°C. The sludge is mainly formed by two organic fractions with different reactivity; the less reactive fraction decomposes and burns at temperatures closer to those of coal, although, in general, slightly lower. For coal-sludge blends, no interactions between the components were detected. The Arrhenius kinetic parameters were calculated from the experimental results, considering the process as a series of consecutive first order reactions. Coal reactivity is scarcely modified as a consequence of a low addition of sludge (10 wt% blends). The 50 wt% blends show two different regions of reactivity. In the lower temperature region (about T < 350°C), the blend reactivity is similar to that of sludge, while in the higher temperature region ( T > 350°C), it is similar to that of coal.
l0
ENGINES Power generation and propulsion, electrical vehicles
well as thrifty energy housekeeping and early detection of possible restrictions of reliability by battery monitoring are necessary functions. To meet today's requirements for battery monitoring and energy management, solutions have been developed for series vehicles launched in years 2001-2003, operating at the 14 V level.
04/01492 Comparative analysis on the part load performance of combined cycle plants considering design performance and power control strategy Kim, T. S. Energy, 2004, 29, (1), 71 85. The purpose of this study was to analyse the relationship between the part load performance and design performance of gas turbines and combined cycle plants. The effect of power control strategy on the part load performance of the combined cycle was also examined. The analysis was carried out using a proven cycle simulation program. Based upon the design performances of actual gas turbines, a consistent principle of design point selection was applied to four different gas turbines representing various technology levels. Tile part load control strategies considered were fuel-only control and IGV control. It h a s been observed that gas turbines with higher design performances exhibit superior part load performances. Since the average combined cycle performance is affected by the range of IGV control, as well as its temperature control principle, a control strategy appropriate for the load characteristics of the individual plant should be adopted.
04/01493 Detergent additives for reduced power loss and power recovery in diesel engines Davenport, J. N. et al. PCT Int. Appl. WO 03 44 134 (CI. C10L1/22), 30 May 2003, GB Appl. 2001/27953. Diesel fuel with reduced engine power losses and reduced smoke or particulate emissions, especially synthetic low-sulfur Fischer-Tropschderived diesel (e.g. by the Shell Middle Distillate Synthesis process), contains 100-500 weight ppm of a detergent. The fuels are evaluated based on a comparison of engine power losses and power recovery after testing the engine on different fuels in successive driving cycles.
04•01489 Actions to promote energy-efficient electric motor repair
04/01494 Development of an autoignition submodel for natural gas engines
de Almeida, A. T. and Ferreira, J. T. E. International Journal of Energy Technology and Policy, 2003, 1, (3), 302-314. Electric motors are repaired 2-3 times over their lifetime. Poor repair practices, particularly widespread in developing countries, can lead to a significant increase in motor losses. It is estimated that worldwide poor repair leads to annual electricity losses of approximately 40 TWb, representing 20 Mtons of CO2 emissions. The main objective of this paper is to provide a technical basis for designing demand side management actions, which address the motor repair market. This paper brings into focus motor repair process trends, energy-efficient motors, typical repair process, actions to promote energy-efficient motor repair, energy-efficient motor rebate schemes to replace old, badly damaged motors and the factors influencing payback. This paper will be useful to energy policy makers, and Demand Side Management (DSM) staff in energy agencies and electric utilities.
Soylu, S. and Van Gerpen, J. Fuel, 2003, 82, (14), 1699-1707. This paper describes a new auto-ignition sub-model for engine modelling codes. This sub-model does not require extensive computational resources and is easily portable to various computational environments. It also considers variation of natural gas composition due to propane addition. Computation results show that the knock occurrence crank angle can be predicted within 2 ° CA when the model is coupled to a zero-dimensional engine model, which was also developed for the present work. The results with the model incorporated into a multi-dimensional model (KIVA) are also promising. KIVA was able to predict if the engine was going to knock or not and also gave correct trends in the knock intensity.
04/01490 Analysis of endgas temperature fluctuations in an si engine by laser-induced fluorescence Schief31, R. and Maas, U. Combustion andFlame, 2003, 133, (1-2), 1927. Spatial temperature fluctuations in the unburned endgas of a sparkignited (SI) engine were investigated. The approach of the study exploits the fact that the quantities (species concentrations, temperature) comprising the state of the combustion chamber gases are not independent, but often correlate sharply. Information about spatial temperature variations is obtained indirectly by observing two complementary quantities that sensitively reflect the local temperature. Spatial formaldehyde (H2CO) concentration variations in the endgas are converted to temperature fluctuations using calculated correlations between temperature and [H2CO]. Additionally, the geometrical size of inhomogeneities is deduced from LIF-images displaying the locally varying formation of temperature-sensitive intermediate species. The results indicate that temperature fluctuations exceeding 20 K are present in the nominally homogeneous endgas. The geometrical size of these fluctuations ranges from ,-~1 mm to ,-~I cm.
04/01491 Battery monitoring and electrical energy management Meissner, E. and Richter, G. Journal o f Power Sources, 2003, 116, (12), 79-98. New vehicle electric systems are promoted by the needs of fuel economy and ecology as well as by new functions for the improvement of safety and comfort, reliability, and tile availability of the vehicle. Electrically controlled and powered systems for braking, steering and stabilization need a reliable supply of electrical energy. The planned generation of electrical energy, the provision of adequate storage, as
04•01495 Ecological optimization for generalized irreversible Carnot engines Chen, L. et al. Applied Energy, 2004, 77, (3), 327-338. The optimal ecological performance of a Newton's law generalized irreversible Carnot engine with losses due to heat-resistance, heat leak and internal irreversibility is derived by taking an ecological optimization criterion as the objective. This consists of maximizing a function representing the best compromise between the power and entropy production rate of the heat engine. A numerical example is given to show the effects of heat leakage and internal irreversibility on the optimal performance of the generalized irreversible heat-engine.
04/01496 Emission characteristics of diesel engine operating on rapeseed methyl ester Nwafor, O. M. I. Renewable Energy, 2004, 29, (1), 119-129. Biofuels are being investigated as potential substitutes for current high pollutant fuels obtained from the conventional sources. In the past, fuels were generally selected on the basis of lowest cost relating to the requirements of the engine, and no attention was given to the possible effects of their use on the environment. Recent concerns over the environment, increasing liquid fuel prices and scarcity of supply in the last decade have promoted interest in the development of alternative sources of liquid energy. The purpose of this research was to evaluate the potential of rapeseed methyl ester (RME) as a liquid fuel for diesel engines in relation to meeting emission requirements. The test results showed that RME and its blends with diesel fuel emitted high CO2 compared to test results on diesel fuel. A significant reduction in emissions of hydrocarbon (HC) was recorded when running on RME and the blends. HC emissions were noted to increase with increased amount of diesel fuel in the blend. The fuel economy was a little worse when running on R M E due to its low energy content. There were no marked difference noted for the exhaust temperatures of the blends, RME and diesel fuel at high-speed operation. However, the diesel fuel
Fuel and Energy Abstracts May 2004 203