Computational Techniques for Microscale Heat Transfer

2008 ◽  
pp. 623-657 ◽  
Author(s):  
Da Yu Robert Tzou ◽  
James C. Dowell
Author(s):  
Minghui Hu ◽  
Dongsheng Zhu ◽  
Jialong Shen

It is requested to develop a microscale and high performance heat exchanger for small size energy equipments. The heat transfer performance of the water film on the condensing coils of the microscale evaporative condenser was studied for a single-stage compressed refrigeration cycle system. Under various operation conditions, the effects of the spray density and the head-on air velocity on the heat transfer performance of the water film were investigated. The results show that the microscale heat transfer coefficient of the water film αw increases with the increase of spray density and decreases with the increase of head-on air velocity. The results indicate that the key factor affecting the microscale heat transfer of the water film is the spray density. As the results, it is measured that the present device attained high heat transfer quantity despite the weight is light. In addition, via regression analysis of the experimental data, the correlation equation for calculating the microscale heat transfer coefficient of the water film was obtained, its regression correlation coefficient R is 0.98 and the standard deviation is 7.5%. Finally, the correlations from other works were compared. The results presented that the experimental correlation had better consistency with the correlations from other works. In general, the obtained experimental results of the water film heat transfer are helpful to the design and practical operation of the microscale evaporative condensers.


2002 ◽  
Author(s):  
S. Srinivasan ◽  
E. Marotta ◽  
J. Ochterbeck ◽  
R. Schwartz ◽  
R. Miller

2006 ◽  
Vol 30 (8) ◽  
pp. 745-754 ◽  
Author(s):  
Sashidhar S. Panchamgam ◽  
Joel L. Plawsky ◽  
Peter C. Wayner

2012 ◽  
Vol 134 (3) ◽  
Author(s):  
Jayathi Y. Murthy ◽  
Sanjay R. Mathur

During the few decades, computational techniques for simulating heat transfer in complex industrial systems have reached maturity. Combined with increasingly sophisticated modeling of turbulence, chemistry, radiation, phase change, and other physics, powerful computational fluid dynamics (CFD) and computational heat transfer (CHT) solvers have been developed which are beginning to enter the industrial design cycle. In this paper, an overview of emerging simulation needs is first given, and currently-available CFD techniques are evaluated in light of these needs. Emerging computational methods which address some of the failings of current techniques are then reviewed. New research opportunities for computational heat transfer, such as in submicron and multiscale heat transport, are reviewed. As computational techniques and physical models become mature, there is increasing demand for predictive simulation, that is, simulation which is not only verified and validated, but whose uncertainty is also quantified. Current work in the area of sensitivity computation and uncertainty propagation is described.


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