Small Cross-Flows in Three-Dimensional Laminar Boundary Layers with Suction or Injection

摘要

Three-dimensional laminar boundary layers with suction or injection are examined by using an approximate method based on a small cross-flow assumption. The basic equations are derived in detail and the computational method is developed. The method is tested against exact solutions and is found to be reasonably accurate. Two examples with the same external condition, but with different surface conditions, are analyzed. In one case the distribution of the normal velocity at the surface satisfies the similarity requirement and in the other case the normal velocity is constant over the complete surface. Although the results of these two cases are different in detail, the general trend of both shows that the three-dimensional behaviour of the boundary layer diminishes with suction and amplifies with injection. (Author)