Thermal optimization of horizontal tubes with tilted rectangular fins under free convection for the cooling of electronic devices

Abstract

In the present work, the horizontal tubes with tilted rectangular fins under free convection are experimentally investigated for the cooling of electronic devices. The temperature differences of horizontal tubes with tilted rectangular fins are measured for several heat inputs, tilt angles, and numbers of fins. Using the measurement results, a correlation for the prediction of the Nusselt number is suggested. This correlation is suitable for the situation for Rayleigh numbers of 200,000-1,100,000, tilt angles of 0°-90°, and numbers of fins of 9-36. On the basis of the correlation, the cooling performances are presented for various numbers of fins and thicknesses of fins, and the value of the optimal cooling performance is found. Finally, the optimal cooling performances of tubes with tilted rectangular fins and conventional radial rectangular fins are compared. The comparison results show that the optimal cooling performance of the tube with tilted fins is 6% greater than that of the tube with radial rectangular fins.