The group theoretic approach is applied for solving the problem of unsteady natural convection flow of micropolar fluid
along a vertical flat plate in a thermally stratified medium. The application of two-parameter transformation group reduces
the number of independent variables in the governing system consisting of partial differential equations and a set of auxiliary
conditions from three to only one independent variable, and consequently the system of governing partial differential
equations with boundary conditions reduces to a system of ordinary differential equations with appropriate boundary conditions.
Numerical solution of the velocity, microrotation and heat transfer have been obtained. The possible forms of the
ambient temperature variation with position and time are derived.
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