ISSN:0145-7632    

DOI:10.1080/01457638108939590

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

An explicit procedure for the design of a system containing a regenerator with bypass has been developed. Bypass of the regenerator during the energy retrieval process is controlled so that the temperature of the recombined fluid stream is held at a selected value. The procedure involves two sets of curves. The design curves relate the specific characteristics of the storage matrix and the mass rate of flow of the fluid through the regenerator. The performance curves relate the nondimensional length and period to the thermal ratio, maximum pressure drop, duration of hot period, and temperature of the combined fluid stream during the retrieval process. The mass of the storage material and dimensions of the regenerator are determined for the specified operating conditions.

ISSN:0145-7632    

DOI:10.1080/01457638108939591

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

A general correlation for heat transfer during subcooled boiling in tubes was compared with a large amount of varied data for boiling in cylindrical annuli. The data include the fluids water, R-113, and methanol; mass fluxes from 2 78 to 7774 kg/m1s; heat fluxes from 0.03 to 4.4 MW/m2; liquid subcooling from 2 to 109°C; and reduced pressures from 0.009 to 0.89. The inner tube diameter varied from 4.5 to 42.2 mm and the annular gap from 1 to 6.6 mm. The data include heating of the inner, outer, and both tubes of the annuli. The 450 representative data points from all studies are correlated with a mean deviation of 8.9%.

ISSN:0145-7632    

DOI:10.1080/01457638108939592

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

The expression for the performance of a gas-cooled heat exchanger per unit of power expended to the flowing gas provides a useful figure of merit for extended-surface heat exchangers. As developed here, the expression accounts for the effects of both increased heat transfer coefficient and increased effective temperature difference with higher power expended. Previous expressions accounted for only the increase in heat transfer coefficient. The convenience of comparing different heat exchanger configurations, as well as different tube spacing in the same configuration, is shown.

ISSN:0145-7632    

DOI:10.1080/01457638108939593

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

Fouling of heat transfer surfaces, which leads to high economic penalties and is still dealt with by heat exchanger designers by the crude TEMA approach, is classified into five principal categories. The measurement of thermal fouling is considered critically, and this is followed by a discussion of the successive events, up to five in number, that characterize most fouling situations. The resulting 5×5 matrix of fouling categories and sequential events illustrates the fact that the fundamental fouling problem has now been mainly resolved, at least for liquid-solid interfaces, although it still remains largely unsolved.

ISSN:0145-7632    

DOI:10.1080/01457638108939594

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

Boiling heat transfer performance on stainless steel metal fiber sintered surfaces is experimentally investigated with Freon 11 (Rll) as the working fluid. The boiling heat transfer coefficient for the optimum surface structure gives a tenfold improvement over a smooth surface. The nondimensional specific parameter including all design parameters is introduced to explain the trend of the performance of various kinds of metal fiber sintered surfaces. Moreover, the metal fiber sintered surface clad with titanium film is suggested to be appropriate to an evaporator for Ocean Thermal Energy Conversion (OTEC)system.

ISSN:0145-7632    

DOI:10.1080/01457638108939595

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

This article presents the three main alternative approaches to the prediction of two-phase flow systems (empirical, analytical, and phenomenological) and explores their advantages and disadvantages. Empirical correlations are the most widely used but have considerable error whereas full analytical treatments are rarely applicable. By understanding the phenomena involved and representing them by simple models, better prediction methods are feasible. This approach is exemplified in its application to the prediction of annular two-phase flow and to the prediction of two-phase flow in equipment, for example a kettle reboiler. The article closes by indicating the possible lines that future development may follow in this area.

ISSN:0145-7632    

DOI:10.1080/01457638108939596

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor