Numerical Simulation Of Rayleigh-benard Convection

The so-called Rayleigh Benard convection is named as the experiment before 1900 and the theoretical analysis in 1916 of Benard.It is in a closed chamber with the bottom heating,the top cooling,resulting in temperature difference thus lead to the fluid flow phenomenon in the cavity.This article uses the method of the large eddy simulation to simulate the dry air Rayleigh Benard convection problem in turbulence in cylinder with constant temperature at bottom and top cylinder,also all wall meeting the condition that there is no slip of speed.And meanwhile,this article focus on the Rayleigh-Benard convection in turbulence with the condition of side cooled.Based on the theory of Navier-Stocks equation and Boussinesq assumption,we researched the Rayleigh-Benard convection in turbulence with different Ra number and Heat Dissipation ratio.Through this study,we found that there is a large scale circulation structures in the flow field,and we discussed the different flow structures,also its variation with different Ra numbers and different heat dissipation ratio.We focus on the analysis of Ra number and Heat Dissipation effect on average velocity,average temperature,velocity field,temperature field and heat dissipation efficiency.Research reveals that Ra and heat dissipation ratio effect on the basic properties of Rayleigh-Benard convection.Finally,I applied Rayleigh-Benard convection to transformers cooling process,and presented the method of the box-top type transformer Rayleigh-Benard convection cooling,and run simulation based on this model,verified its feasibility,at the same time proposed the optimization scheme.