Heat transfer augmentation techniques in forced flow V-trough solar collector equipped with V-cut and square cut twisted tape

Abstract

Abstract The enhancement in the heat transfer (Nu), friction factor (f) and thermal performance (η) for a forced circulation V trough solar collector fitted with helix twisted tape (HTT), helix with square cut twisted tape (HSCTT) and helix with V cut twisted tape (HVCTT) with two different twist ratios (3 & 5) have been verified by experimentation. The experiments have been carried out within a range of Reynolds numbers between 3000 and 23,000. The use of additional V trough reflector has increased the thermal performance of the collector in comparison with a flat plate collector (FPC) by 8.4%. Experimentation has been carried out with HSCTT and HVCTT. The HVCTT has given better thermal performance than HSCTT for an identical twist ratio. The empirical correlations have been developed to match the experimental Nusselt number (Nu), friction factor (f) and thermal performance (η) with variations of ±6.107%, ±9.44% and ±5.96% respectively.