Experimental Investigation on Two-Phase Flow in Horizontal Channel with Vortex Generator

Abstract

Vortex generator can be used to enhance heat transfer as it is capable of providing better mixing. Vortex generator is easy to manufacture and install in heat transfer units without much additional cost. Present work is planned to investigate the effect of vortex generators on local heat transfer coefficient, critical heat flux (CHF) and pressure drop to ensure design and safety of heat transfer units with vortex generators. Experiments are carried out for three values of pitch 22, 32 and 41 mm and an angle of attack of 45° of vortex generators with horizontal configuration in a smooth tube of diameter 11.9 mm, length 1,000 mm and 0.4 mm wall thickness with R-123 as the working fluid. The effect of mass flux (175–681 kg/m2s) and heat flux (7.9 − 221.7 kW/m2) are studied. Both horizontal and vertical-oriented configurations of the vortex generator are tested. Local wall temperature measurement is carried out with Infrared thermography. Comparing results with plain tube shows the heat transfer coefficient and CHF enhancement. Horizontal orientation (HO) of the vortex generator gives better results than the vertical orientation (VO). Heat transfer coefficient, CHF and pressure drop penalty increase with a decrease in the pitch of the vortex generator.