Experimental Study on the Effects of Shear on Co‐Currently Swirling Steam‐Water Flow Instabilities

Abstract

The shear effect of co‐currently flowing water on the flow instabilities induced by swirling steam was investigated. With shear, a 22–27 % decrease in velocity fluctuation amplitude was observed. The decrease was 29–41 % on an exponential and 12–17 % on a proportional basis. Shear reduced the layer thickness on increasing the inlet water pressure from 1 to 2 bar by 1.9–2.9 and 6.35–12.89 % at steam inlet pressures of 1 and 2 bar, respectively. The ratio of the swirl intensity along the dimensionless axial length scale and the initial swirl intensity was changed from < 1 to > 1 across critical point due to the nearly equal values of buoyancy and rotational frequencies. A critical limit of the initial swirl intensity within the control plane was investigated wherein the swirl‐induced instabilities can be attenuated uniformly and the rotational effects dominate over the gravity waves and buoyancy.

Experimental and computational study of convective heat fluxes in swirling two‐phase flows

“…The experimental setup 15 can be seen in Figure 1A,B. The experimental setup is a cylindrical shape flow rig with a length of 3 m and a diameter of 18 in.…”