Strength Of Horseshoe Vortex Research Articles

Numerical analysis of vane endwall film cooling and heat transfer with different mainstream turbulence intensities and blowing ratios

In present study, effects of mainstream turbulence intensity and blowing ratio on the endwall film cooling and heat transfer are numerically investigated. Upstream double-row streamwise cylindrical holes with inclination angel (θ) of 30 deg is applied. Four blowing ratios (M = 0.5, 1.0 1.5, 2.0) and three turbulence intensities (Tu = 5%, 15%, 25%) are studied. Distributions of film cooling effectiveness and heat transfer coefficient are presented together with vortex structure. Results show that with the increasing of blowing ratio, the strength of horseshoe vortex is significantly weakened and the level of film cooling effectiveness is obviously improved. In addition, the low heat transfer zone downstream the holes and upstream the leading edge is enlarged because of the increased momentum, while the high heat transfer zone at the exit of passage gradually shrinks. With the increasing of turbulence intensity, the variation of film cooling effectiveness is very limited, but the level of heat transfer near the pressure side in the second half of the vane passage obviously decreases. Moreover, a more uniform film coverage and heat transfer distribution is obtained at high turbulence intensities.

A review on hydrodynamics of horseshoe vortex at a vertical cylinder mounted on a flat bed and its implication to scour at a cylinder

A comprehensive review of the local scour due to vortical flow around a cylindrical bridge pier under steady current is presented in this paper. The mechanism of the formation of vortices, the size, velocity and strength of horseshoe vortex (HSV), formation of the HSV by the separation of laminar and turbulent boundary layer and the scour around a cylindrical pier due to vortices have been presented. The complexity involved in the scour-related calculations, and the scope for future research are discussed in the last section.