Exact Solution of Three-Dimensional Unsteady Stagnation Flow on a Heated Plate

In this study three-dimensional unsteady stagnation flow and heat transfer impinging on a flat plate are investigated in a Cartesian coordinate system when the plate is moving with variable velocity and acceleration towards the main stream or away from it. An exact solution is obtained in this problem for the axisymmetric case. An external fluid, along z-direction, with strain rate a impinges on this flat plate and produces an unsteady three-dimensional flow in which the plate moves along z-direction with variable velocity and acceleration. A reduction of Navier Stokes and energy equations is obtained by use of appropriate similarity transformations. Velocity, boundary-layer thickness, and surface stress-tensors along with temperature profiles are presented for different values of impinging fluid strain rate, different values of plate velocities, and Prandtl-number parameter for the case of steady state.