Effect of modified gravitational acceleration (g) on Natural convection results

vidyadhar · November 5, 2017, 08:03

Hello,

I am simulating natural convection problem in Fluent- vertical plate with fins (conjugate heat transfer problem).

To achieve different Rayleigh numbers, I am modifying acceleration due to gravity, by keeping other parameters constant.

1. How to assess the results such as Nusselt number, heat transfer rate? -when gravity is modified from "9.81". Do I have to use any multiplying factors to get the actual values which would have been obtained at the normal value of g=9.81?
2.How far this procedure gives correct results? Does the heat transfer coefficient and surface temperature of fins which were obtained with modified gravity and with g=9.81 are same (-provided Rayleigh number being the same in both cases)?

Thanks in advance,
Vidyadhar

AlexanderZ · November 5, 2017, 20:30

Why do you think, that G will influence Re and Pr directly?

Best regards

vidyadhar · November 5, 2017, 23:15

Hi,

No 'g' will not influence Re, Pr

November 5, 2017, 08:03	Effect of modified gravitational acceleration (g) on Natural convection results	#1
vidyadhar Senior Member vidyadhar Join Date: Jul 2016 Posts: 138 Rep Power: 9	Hello, I am simulating natural convection problem in Fluent- vertical plate with fins (conjugate heat transfer problem). To achieve different Rayleigh numbers, I am modifying acceleration due to gravity, by keeping other parameters constant. 1. How to assess the results such as Nusselt number, heat transfer rate? -when gravity is modified from "9.81". Do I have to use any multiplying factors to get the actual values which would have been obtained at the normal value of g=9.81? 2.How far this procedure gives correct results? Does the heat transfer coefficient and surface temperature of fins which were obtained with modified gravity and with g=9.81 are same (-provided Rayleigh number being the same in both cases)? Thanks in advance, Vidyadhar

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November 5, 2017, 20:30		#2
AlexanderZ Senior Member Alexander Join Date: Apr 2013 Posts: 2,363 Rep Power: 34	Why do you think, that G will influence Re and Pr directly? Best regards

November 5, 2017, 23:15		#3
vidyadhar Senior Member vidyadhar Join Date: Jul 2016 Posts: 138 Rep Power: 9	Hi, No 'g' will not influence Re, Pr