Effect of Richardson Number on Entropy Generation Over a Backward Facing Step

CHEN Sheng

doi:10.3879/j.issn.1000-0887.2012.11.008

Volume 33 Issue 11

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CHEN Sheng. Effect of Richardson Number on Entropy Generation Over a Backward Facing Step[J]. Applied Mathematics and Mechanics, 2012, 33(11): 1330-1339. doi: 10.3879/j.issn.1000-0887.2012.11.008

Citation:

CHEN Sheng. Effect of Richardson Number on Entropy Generation Over a Backward Facing Step[J]. Applied Mathematics and Mechanics, 2012, 33(11): 1330-1339. doi: 10.3879/j.issn.1000-0887.2012.11.008

Citation:

CHEN Sheng. Effect of Richardson Number on Entropy Generation Over a Backward Facing Step[J]. Applied Mathematics and Mechanics, 2012, 33(11): 1330-1339. doi: 10.3879/j.issn.1000-0887.2012.11.008

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Effect of Richardson Number on Entropy Generation Over a Backward Facing Step

doi: 10.3879/j.issn.1000-0887.2012.11.008

CHEN Sheng^{1,2
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¹Research & Development Center, WISCO, Wuhan 430083, P.R.China;²State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, P.R.China

Received Date: 2011-11-17
Rev Recd Date: 2012-05-05
Publish Date: 2012-11-15

Abstract

Abstract

Flow over a backward facing step (BFS) has been taken as a useful prototype to investigate characteristics of separated flow with heat transfer. However, to date the study on the effect of Richardson number on entropy generation over BFS is absent yet although the flow pattern and heat transfer characteristic both would receive significant influence caused by variation of Richardson number in many practical applications, for example in microelectromechanical systems and aerocrafts. The effect of Richardson number on entropy generation in BFS flow was reported for the first time. Results of entropy generation analysis was obtained by numerically solving the entropy generation equation. The values of velocity and temperature, which were the inputs of the entropy generation equation, were obtained by the lattice Boltzmann method.It is found that the distributions of local entropy generation number and Bejan number are significantly influenced by the variation of Richardson number. The total entropy generation number is a monotonic decreasing function of Richardson number whereas the average Bejan number is a monotonic increasing function of Richardson number.
- entropy generation,
- backward facing step,
- Richardson number,
- lattice Boltzmann method

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References(22)

References

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