Thermal analysis of surface-gas heat transfer augmentation using a particle periodically in contact with a surface

摘要

In this study a method of heat transfer enhancement between a surface and a fluid is investigated.Heat transfer enhancement is due to periodic contact of a cubic particle with the surface and the fluid.The system analyzed was a cycle where a cube would contact a wall and then be inmmersed in fluid.This process would continue with the sides of the cube contacting the wall in a progressive order (i.e.1,2,3,4,5,6,1,2,..),until the cube reached a quasi-steady state (long time transient).An analytical solution using Green's function is compared to a numerical solution for the first contact time.The effect of contact conductance between the surface and the particle,the size of the particle,and the contact time with the surface and the fluid on the quasi-steady state heat transfer were investigated.the contact conductance between the surface and the particle plays an important role in the magnitude of heat transfer augmentation.