Wave Instability Of Natural Convection Flow On Inclined Flat Plates With Uniform Surface Heat Flux

H. C. Tien
T. S. Chen, Missouri University of Science and Technology
Bassem F. Armaly, Missouri University of Science and Technology


The wave instability of laminar natural convection flow adjacent to horizontal, inclined, and vertical plates with uniform surface heat flux is analyzed by the linear theory. In the analysis the main flow is treated as nonparallel, and the disturbance thermal condition at the wall is examined by considering the thermal capacity of the plate. The eigenvalue problem consisting of a linearized system of coupled ordinary differential equations for the disturbance amplitude functions is solved by a fourth-order Runge-Kutta integration scheme, along with an orthogonalization procedure to remove the truncation errors. Neutral stability curves and critical Grashof numbers are presented for fluids having Prandtl numbers of 0.7 and 7 for inclination angles ranging from 0 to 90°. The present results are compared with those from vortex instability analysis and with those from wave instability analysis for the case of uniform wall temperature. They are also compared with previous analytical results and available experimental data for the special case of a vertical plate. © 1986 Taylor & Francis Group, LLC.