Numerical Modelling and Thermohydraulic Analysis of Circular Pipe Having Internal Vortex Generators

In the present work, a numerical investigation has been performed to investigate the thermohydraulic performance of a circular pipe used in a heat exchanger with and without insertion of vortex generators. Vortex generators (VGs) which are used inside the pipe having dimensions of blockage ratio 0.3 and attack angle of 0°. The investigation has been carried out for Reynolds number (Re) ranges from 6000 to 24,000. Two cases of implementing vortex generators namely two VGs configuration and four VGs configuration have been investigated and compared with a smooth pipe which is of the same geometric parameters. Nusselt number (Nu) and friction factor (f) have been considered for representing the thermal and hydraulic characteristics, respectively. The overall performance of the two VGs and four VGs configuration has been calculated using the thermal performance enhancement factor (TPE). It has been found from the results that using VGs, heat transfer rate of smooth pipe can be improved while pressure drop also increased compared to the smooth pipe. With the increase in Re, Nu of all the cases increased with a significant decrement in friction factor (f). The overall performance in terms of TPE is maximum for four VG configuration at Reynolds number of 6000.