The Effect of Mass Transfer on Heat Transfer in Higher-Order Boundary Layers.

A determination of the second approximation to the solution of the Navier-Stokes equations for incompressible, 3-dimensional flow near the stagnation line on a swept cylinder. Using the method of matched asymptotic expansions to determine the coefficients in expansions for the flow-velocity components, pressure, temperature, crossflow at the wall, and wall concentration, the authors studied the effect of wall mass transfer on the second-approximation coefficients for longitudinal curvature and displacement. The results were that longitudinal curvature and displacement effects are negative and lead to decreasing values of boundary-layer characteristics. This can be explained by the stretching of the boundary layer normal to the wall by the centrifugal forces due to the convex surface curvature. Increasing mass injection at the wall heightens all second-order effects, because of the thickening in the boundary layer. The sole exception is the longitudinal curvature effect on wall concentration: it increases the wall concentration. This increase is diminished by mass injection. 39 pp. Ref. (SM)