Experimental and Computational Investigation of Forced Convection Analysis of Plate Circular Pin Fin Heat Sinks over Vertical base

Abstract

It is essential to provide adequate cooling in electronic components to avoid overheating and increase the performance of the system. Recognizing the poor heat transfer performance of air-cooling, secondary fin surface is usually exploited to solve the increased demand of heat dissipating. For further improvement of the overall heat transfer performance, augmentation via fin pattern is often employed. Among the fin configurations being implemented in practical applications, pin fin is regarded as one of the most effective heat transfer augmentation methods for providing boundary layer restarting and periodic vortex shedding. For rectangular plate fin heat sinks it has been observed that there is boundary layer growth in forced convection, which decreases the heat transfer rate. To overcome this problem, some circular fins are inserted in the passage of plate fin. By doing so an average heat transfer coefficient of the rectangular plate pin fin heat sink (PPFHS) was increased compared to rectangular plate fin heat sink (PFHS) under the condition of equal wind velocity. A comparative study of plate fin heat sinks and plate pin fin heat sinks having circular cross-section pin over vertical base was done and it is found that for an inline arrangement, circular pin fin shows an appreciable influence of fin density, fin spacing. This is associated with the unique deflection flow pattern accompanied with the inline circular configuration. The present study carries out the parametric, numerical computations of the plate-circular pin-fin heat sink on vertical base and provides physical insight into the flow and heat transfer characteristics in forced convection. The parameters such as fin spacing, fin density, heat input and Reynolds number has been varied to observe the variation of thermal performance PFHS and PPFHS on vertical base. Limited experimentation is carried out to validate the numerical model. Numerical analysis is carried out to compare thermal performance of plate fin and plate pin fin heat sink under the condition of equal temperature difference between mean sink temperature and the ambient temperature. The effect of fin spacing, pin fin diameter and temperature difference between fin and surroundings on the forced convection heat transfer from vertical fin arrays were studied. The analysis have been carried out for the two type of heat sinks with three different spacing, three different pin diameters and five temperature differences. The result shows that there is 18–22% increase in rate of heat transfer and 20–25% increase in profit factor for PPFHS as compared to PFHS on vertical base.