Numerical study on turbulent characteristics of wall jet in a quiescent environment over a plate in motion

Abstract

The present article reports the numerical analysis of a two dimensional turbulent wall jet flow over a horizontal moving plate in a quiescent environment. The simulation is done using the low-Reynolds number turbulence model proposed by Yang and Shih [21]. The turbulent characteristics are observed for various velocity ratio of plate with respect to jet (Up ) from keeping Reynolds number at jet inlet to be constant at 15000. The Reynolds averaged Navier Stokes (RANS) equations are discretized using the finite volume method and solved in steady state condition. The pressure correction technique applied to couple the velocity and pressure terms is SIMPLEC (semi-implicit pressure linked equation-consistent). The variation of jet half-width and the decaying local maximum velocity (Umax ) for the bottom plate moving with high velocity (Up > 1) shows dominancy of plate motion over the jet stream in the flow field. The velocity contour diagram shows the velocity distribution in the flow field. The Reynolds stresses induced in the wall proximate regions are directly proportional to the relative motion of the flow field but the magnitude of Reynolds stress away from wall decreases by increasing the plate velocity. The plate motion significantly affects the turbulence characteristics and the flow field in the viscous laminar zone of the wall region.