EFFECT OF REYNOLDS NUMBER ON THE SUCTION INFLUENCE ON THE TURBULENT BOUNDARY LAYER STRUCTURES

Abstract

The effect of Reynolds number on the influence of suction on the turbulent
boundary layer structures has been quantified through the measurements of
third- and fourth-order turbulence statistics for several suction rates and streamwise locations downstream of the suction strip. Third- and fourthorder
turbulence statistics are more sensitive to a change in boundary condition than second-order moments. The data of the third-order turbulent statistics reveal an alteration in the turbulent transport as a result of the manipulation of the organised motion by suction. The alteration is increased as the suction rate is increased but reduces as the Reynolds number is increased. The results support that, relative to no suction case, Reynolds number modulates the behaviour of higher-order turbulent statistics without changing the actual mechanism of suction on the boundary layer. In general, it is proposed that Reynolds number effect on suction influence in a turbulent boundary layer is universal for the large-scale quantities. This argument is supported by the behaviour of root mean square fluctuating spanwise vorticity.