영향계수법을 이용한 돌출형 거칠기가 있는 이중관내의 난류유동과 열전달의 예측

The fully developed turbulent momentum and heat transfer Induced by the square-ribbed roughness elements on both the Inner and outer wall surfaces In concentric annuli are studied analytically based on a modified turbulence model. And the heat transfer in the both heated walls was calculated using influence coefficient method. The analytical results of the fluid flow is verified by experiment. The study demonstrates that certain artificial roughness elements may be used to enhance heat transfer rates with advantage from the overall efficiency point of view by Investigating tubulent flows and heat transfer in Fig. 1.