TY - JOUR
TI - Experimental and numerical investigation of thermal performance of channels with staggered array-based dimples
AU - Xie Yong-Hui
AU - Shen Zhong-Yang
AU - Liu Tian-Yuan
AU - Xie Gong-Nan
JN - Thermal Science
PY - 2015
VL - 19
IS - 11
SP - 213
EP - 219
PT - Article
AB - Numerical simulation coupled with experimental method was carried out to  study the flow and heat transfer characteristics in rectangular channel with  staggered array-based dimples. The effect of different dimple depths and  Reynolds number were investigated using the shear stress transport turbulent  model coupled with gamma-theta transition model. The results indicated that  heat transfer and flow resistance of the dimpled surface increases with the  increase of dimple depth. Moreover, the thermal performance is sensitive to  the flow transition. Heat transfer in each single dimple region increases  monotonously in the streamwise direction with Reynolds number increasing.  Heat transfer characteristics almost remain the same when the flow is under  fully laminar or turbulent but increases greatly when the flow is transited  from laminar condition to turbulent condition. Besides, the variations of  friction coefficients and thermal performance coefficients are quite similar  to those of heat transfer enhancement coefficients, which firstly increases  then decreases with the increase of Reynolds number. By comparing the  experimental and numerical results, it is found that staggered array-based  dimples with δ/D = 0.2 was the most effective structure from the aspect of  thermal performance.