Experimental and numerical investigation of heat transfer, temperature distribution, and louver efficiency on the dimpled louvers fin banks

Abstract

Numerical models have been developed by commercial package Fluent 6.3 to simulate the air flow through single dimple, simple, and dimpled louvers in low and medium Reynolds numbers. Experiments have also been conducted to measure the temperature and heat transfer in these geometries. Heat transfer augmentation of 8% has been observed by implying dimples on louver at the same mass flow rate. For accurate investigation of the effect of dimple, a single dimpled surface has been modeled numerically and experimentally. The simulation revealed that these heat transfer and temperature augmentations occur due to existence of a circulation region created by dimple. Additionally, the effects of louver's thermal resistance on temperature distribution over the louver surface have been considered to gain the actual contours. Continuous temperature gradients have been observed over the louver surface with the highest temperature at the base of the louver and the lowest temperature at the middle of the louver. Louver efficiency has been introduced to assess the dimpled louver performance for low and medium Reynolds numbers. It has been observed that dimpled geometry has satisfactory louver efficiency. Good agreement has been observed between experimental and numerical models.