01870 Using an emulator to evaluate the performance of building energy management systems

01870 Using an emulator to evaluate the performance of building energy management systems

11 Process heating, powr 95/91%9 Shsar-oppossd mlx~nvsctlon flow and hut transfsr in a narrow, vortlcal cavltv Mansottr, R. B. and Viikanta, R. Int...

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Process heating, powr

95/91%9 Shsar-oppossd mlx~nvsctlon flow and hut transfsr in a narrow, vortlcal cavltv Mansottr, R. B. and Viikanta, R. Int. i. Heat & Fluid Flow, Dec. 1994, 15, (6), 462-469. A combined experimental and theoretical study has been carried out to investigate mixed-convection heat transfer in a narrow, vertical cavity. The shear force is produced at the left side of a cavity b a belt moving upward that constitutes the sixth wall of the cavity. The leg wall of the cavity was cooled and the opposite (right wall) was heated. Hence, the buoyancy force tries to brin the fluid down, and the shear force tends to induce upward fluid flow. # e test cell was equipped with two heat exchangers and three thermocouple racks for mm the temperature distributions at 12 different positions. The temperature field was scam~cd in the cavity for variconditions. Three- and twoous flow and temperature bound dimensional laminar models were usV to analyze the problem thcorctitally. Experimental measurements were found to be in agreement with the numerical predictions. WOW50 Solldlflcatlon of moltsn metal droplsta lmplnglng on s cold surfacs Inada, S. and Yang, W. J. Experimental Heat Transfer, Apr.-Jun. 1994,7, (2), 93-100. TwOti riments arc conducted to stud flow and heat transfer bchaviour in a moT ten metal droplet on a cold sd ace following impingement. Laser holographic interferomctry is employed to visualize molten metal-solid contact state in real time over the entire solidification process b means of a high-speed video camera. The formation of two distinct sob*&cd layers is disclosed. One, formed in the early states of solidification, adheres to the cooling surface and is latent heat controlled. The other, formed in the later stage, 1s nonadhesive and radial-shaped, and is dominated by a slip flow of the molten phase accompanied by phase change. %I01 861 The structun of ths hsat-affsctsd zons In welds of a NI-29 wt.% MO commorclal alloy (Hastelloy S2) Cao, S. et aL, Mater. Charact.,1994, 33, (1). 21-32. The paper examines the microstructure of a welded Hastealloy B2 pipe removed from a coal gasification plant. Although this alloy is susceptible to severe embrittlement if ordering occurs, no sign&ant ordering was found in the heat-affected zone or weld, and the s imens were ductile. However, intergranular corrosion was found in the r cat-affected xone, and 0.1 mm particles of MO-rich M,,C carbide and NiMo intermetallic compound wire found in the grain&~~~~darics. These phases are a parcntly depleting the adjacent matrix of MO and rendering the grain- go undary region susceptible to corrosion. 95/01552 Study of hsat transfsr augmentation In a hlgh-trmperaturs flsld by a mdlatlon promoter nmsmtlna a sscondarv

now

EjAilts,

K.

et al.,

Experimental

Heat

Transfer, Jan.-Mar. 1994, 7, (l),

Characteristics of flow and heat transfer have been investi ated for a circular pipe in which a pair of twisted tapes were insertc d to enhance the convective and radiative heat transfer. From the measurement of the thrcedimensional velocity field, it was clarified that a seamdary flow was induced by the present promoter, heat transfer performance was enhanced about three times compared with that of a smooth pi and a remarkable increase of the local heat transfer rate was observe 8”near the impinging region of the secondary flow. The performance of the present promoter was evaluated based on the total surface area for heat transfer under the same conditions of flow rate, pressure loss, and heat load.

%/01955 on0

and incineration (energy appkWons

in industry)

Thsrmal onorgy stomgr dsslgn - Sack to squars

Roscnfeld, S. I.

Heat. [email protected] Con&., Aug. 1994,66, (E), 79-87.

Discuascs why at the moment the odds are stacked against thermal ener storage since too much emphasis is placed on its appbcation and not on t!?e fundamentals. Topics include: electrical rate structure, outdoor design conditions, daily temperature range, coincidental wet bulb temperature, cnerv simulation programs, hourly cooling loads, economiscr data, cooling cod load, cooline plant load profile, and the last on-peak how. Also notes inconsistenues in ASHRAE Fundamentals Handbook.

%I01886

Tmnrlent tempsmtum dlstrlbutlons In sphertcal and cyllndrlcal food products subjsctsd to hydrocoollng

Dincer, I.

Int. J. Energy Research, Nov. 1994, 18, (6). 741-749.

Analytical models were proposed to estimate the dimensionless tcmpcrature distributions of spherically and cylindrically shaped objects during cooling. In order to test the analytical model, an experimental investigation was carried out to measure temperatures at the ccntre, half radius and surface positions of the spherical and cylindrical products (pears and eggplants) subjected to hydrocooling. The measured temperature distributions were compared with the computed temperature distributions and very good agreement was observed.

95/01%7 Trsatmmt of Irrsgular gsomatrlss using a Cartsslan coordinate0 flnlts-volume radlrtlon hut transfer procsduro Ct&,Ji C. et al., Numerical Heat Transfer, Part B, Sep. 1994, 26, (2), -

.

The article oresents a blocked-off-reaion nrocedure to model radiative transfer in Gegular geometries using aLrt&ian coordinates finite-volume method. Straight-edged, inclined and curved boundaries can be treated. It is capable of handlin&!uarticioatinx or transuarcnt media enclosed bv black or r&.cting walls. Mih this ~~oc&re, irr&lar geometries can &specified through the problem specification potion of the program. Four test problems are used to show that the procedure is capable of reproducing available results for inclined and curved walls, transparent. nonscattering, and anisotropically scattering media.

%I01 888 Two-dlmmslonal roughnear elementa y$ke, - .

jet lmplnglng on a wall with

G. et al., Experimental Heat Transfer, Jan.-Mar. 1994, 7, (l),

Since a very high heat transfer coefficient can be obtained by an im inging jet * its sta at+ region, *s flow geometry has been used for ! eating, coolmg, anP drymg m a variety of industrial applications. This hi@ heat transfer coefficient, however, deteriorates ra ‘dly with the strcamw~se distance downstream of the stagnation line, an %hence the broad downstream region is targeted by the present study on heat transfer augmentation; largescale roughness elements of a transverse repeated-rib type are mounted over the heat transfer surface. The experimental results obtained at various jet velocities indicate effective heat transfer augmentation.

%I01869 The usa of a pwmsable osramlc for radlatlon enhancsmmt in a gas-fired furnace Duckcrs. J. G. Proc. 2nd Int. Con& Ceramics in Energy Applications, The Instihde of Energy, 18 Devonshire St., London WlN 2AU, 1994, 121-136.

%I01 552 Study on coks dsgmdatlon In blast furnace with hlnh oxynsn-enriched coal Inlsctlon Mi K. a&iLi,J. Gang@ 1994; 29, (S), l-4. (In Chinese) Discusses the reaction tern rature ratio of ore to coke gas composition and c loss and degradation in blast furnaces with velocity determine the coE” high oxygen enrichment and coal injections. A high CO or H2 content of the gas will increase the rate of coke loss and degradation. 95lol954 The thermal cycling parformanca of ceramics for gas flrsd furnacsa Khela, S. et al., Proc. 2nd Int. Conf:Ceramics in Energy Applications, The Institute of Energy, 273-290.

To improve the thermal efficiency of high temperature gas-fired furnaces, it is desirable to utiliae as much of the energy in the combustion products as possible before they are exhausted to atmGspherc. Any tcchniqie which inacases the convective or radiative heat transfer from the combustion roducts within a furnace reduces the exhaust temperature. Convective geat transfer can be enhanced by techniques such as jet impingement heating and the use of high velocity burners, but because convection usually accounts for only a smsll proportion (
18 Devonshire Sk, London WIN 2AU, 1994,

A programme of work has been carried out to investigate the effects of thermal shock and thermal cycling on a range of reactIon bonded silicon carbides. Thermal shock tests involved holdin the samples at temperatures for approximately 30 minutes before quenc&g in water held at 20°C. Room temperature four point bend flexural strength tests showed lar e reductions in strength for samples with down shocks in excess of 300”E . The damage was apparent as cracks, in some cases extending across the entire width of the samples.

95lO1070

Using an emulator to evaluate the parformancs of bulldlng energy management systems Kc11 , G. E. et al., Paper No.NO-94-23-4, ASHRAE Tram., 1994, 100, 14s~1493.

The paper describes the use of an emulator to evaluate a buildin energy management system (BEMS . Topics include setting up a BEM 8 and an emulator, evaluating syste m)command and direct digital control software, plus methodologies for testing BEMS application algorithms.

Furl and Energy Abstracts March 1995

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