Minimum entropy generation for laminar flow at constant wall temperature in a circular duct for optimum design

2009 ◽  
Vol 45 (11) ◽  
pp. 1415-1421 ◽  
Author(s):  
Alper Yilmaz
Keyword(s):  
Laminar Flow ◽  
Optimum Design ◽  
Entropy Generation ◽  
Wall Temperature ◽  
Minimum Entropy ◽  
Constant Wall Temperature ◽  
Circular Duct ◽  
Minimum Entropy Generation

Entropy generation through hexagonal cross-sectional duct for constant wall temperature in laminar flow

2004 ◽  
Vol 28 (8) ◽  
pp. 725-737 ◽  
Author(s):  
Hakan F. Öztop ◽  
Ahmet Z. Şahin ◽  
İhsan Dağtekin
Keyword(s):  
Laminar Flow ◽  
Entropy Generation ◽  
Wall Temperature ◽  
Constant Wall Temperature ◽  
Cross Sectional

Entropy generation analysis of nanofluid flow in a circular tube subjected to constant wall temperature

2012 ◽  
Vol 39 (8) ◽  
pp. 1169-1175 ◽  
Author(s):  
K.Y. Leong ◽  
R. Saidur ◽  
T.M.I. Mahlia ◽  
Y.H. Yau
Keyword(s):  
Entropy Generation ◽  
Wall Temperature ◽  
Circular Tube ◽  
Nanofluid Flow ◽  
Constant Wall Temperature

scholarly journals Thermohydraulic Performance and Entropy Generation of a Triple-Pass Solar Air Heater with Three Inlets

Energies ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 6399
Author(s):  
Nguyen Minh Phu ◽  
Ngo Thien Tu ◽  
Nguyen Van Hap
Keyword(s):  
Reynolds Number ◽  
Air Temperature ◽  
Entropy Generation ◽  
Solar Air Heater ◽  
Minimum Entropy ◽  
Air Heater ◽  
The Third ◽  
Thermohydraulic Efficiency ◽  
The Difference ◽  
Minimum Entropy Generation

In this paper, a triple-pass solar air heater with three inlets is analytically investigated. The effects of airflow ratios of the second and third passes (ranging from 0 to 0.4), and the Reynolds number of the third pass (ranging from 8000 to 18,000) on the thermohydraulic efficiency and entropy generation are assessed. An absorber plate equipped with rectangular fins on both sides is used to enhance heat transfer. The air temperature change in the passes is represented by ordinary differential equations and solved by numerical integration. The results demonstrate that the effect of the third pass airflow ratio on the thermohydraulic efficiency and entropy generation is more significant than that of the second pass airflow ratio. The difference in air temperature through the collector shows an insignificant reduction, but the air pressure loss is only 50% compared with that of a traditional triple-pass solar air heater. Increasing the air flow ratios dramatically reduces entropy generation. Multi-objective optimization found a Reynolds number of 11,156 for both the airflow ratio of the second pass of 0.258 and airflow ratio of the third pass of 0.036 to be the an optimal value to achieve maximum thermohydraulic efficiency and minimum entropy generation.

Second-Law Analysis on Wavy Plate Fin-and-Tube Heat Exchangers

1998 ◽  
Vol 120 (3) ◽  
pp. 797-800 ◽  
Author(s):  
W. W. Lin ◽  
D. J. Lee
Keyword(s):  
Entropy Generation ◽  
Operating Conditions ◽  
Generation Rate ◽  
Entropy Generation Rate ◽  
Second Law ◽  
Spanwise Direction ◽  
Minimum Entropy ◽  
Tube Heat Exchanger ◽  
Second Law Analysis ◽  
Minimum Entropy Generation

Second-law analysis on the herringbone wavy plate fin-and-tube heat exchanger was conducted on the basis of correlations of Nusselt number and friction factor proposed by Kim et al. (1997), from which the entropy generation rate was evaluated. Optimum Reynolds number and minimum entropy generation rate were found over different operating conditions. At a fixed heat duty, the in-line layout with a large tube spacing along streamwise direction was recommended. Furthermore, within the valid range of Kim et al.’s correlation, effects of the fin spacing and the tube spacing along spanwise direction on the second-law performance are insignificant.

Minimum entropy generation for isothermal endothermic/exothermic reactor networks

AIChE Journal ◽  
2014 ◽  
Vol 61 (1) ◽  
pp. 103-117 ◽  
Author(s):  
Paul G. Ghougassian ◽  
Vasilios Manousiouthakis
Keyword(s):  
Entropy Generation ◽  
Minimum Entropy ◽  
Reactor Networks ◽  
Minimum Entropy Generation

The influence of Dean Number on heat transfer to Newtonian fluid through spiral coils with constant wall temperature in laminar flow

2016 ◽  
Vol 53 (5) ◽  
pp. 1843-1850 ◽  
Author(s):  
Rahul Harishchandra Patil ◽  
Mariappan Dharmaraj Nadar ◽  
Rashed Ali
Keyword(s):  
Heat Transfer ◽  
Laminar Flow ◽  
Newtonian Fluid ◽  
Wall Temperature ◽  
Dean Number ◽  
Constant Wall Temperature ◽  
Spiral Coils

Laminar flow in annuli ducts with constant wall temperature

1998 ◽  
Vol 25 (2) ◽  
pp. 227-236 ◽  
Author(s):  
Yung-Ming Lee ◽  
You-Ming Kuo
Keyword(s):  
Laminar Flow ◽  
Wall Temperature ◽  
Constant Wall Temperature
Sign in / Sign up

Export Citation Format

Share Document