Nonparallel Stability of Two-Dimensional Nonuniformly Heated Boundary Layer Flows

An analysis is presented for the linear stability of water boundary-layer flows over nonuniformly heated flat plates. Included in the analysis are disturbances due to velocity, pressure, temperature, density, and transport properties as well as variations in the liquid properties with temperature. The method of multiple scales is used to account for the nonparallelism of the mean flow. In contrast with previous analyses, the nonsimilarity of the mean flow is taken into account. No analysis agrees, even qualitatively, with the experimental data when similar profiles are used. However, both the parallel and nonparallel results qualitatively agree with the experimental results of Strazisar and Reshotko when nonsimilar profiles are used.