A direct formulation of correlations for wall-proximity corrections of hot-wire measurements

Correlations for corrections to hot-wire data for the effects of wall proximity within the viscous sublayer are usually presented in the form u/u = F (y u/). The application of such correlations requires a prior knowledge of the wall shear stress; alternatively, the correlation must be used in an iterative fashion. It is shown in the present note that any such correlation may be recast with no loss of generality in the explicit form u/u_m = f (y u_m/), which is more convenient for use.List of symbols u difference between measured and actual velocities, u_m – u - u_m measured velocity - u shear velocity, - u⁺ on-dimensional velocity, u/u - y distance from wall - y⁺ non-dimensional distance from wall, y u/ - fluid density - fluid kinematic viscosity - _s wall shear stress