Simplification of the Expansions of Viscous Terms in Basic Aerodynamic Equations in Non-Orthogonal Curvilinear Coordinate System

The application of non-orthogonal curvilinear coordinate system to the calculation of the flow field inside the channel,with complex boundary geometry,can effectively simplify the work of designing the calculation program and improve the accuracy of calculation[1].Therefore,it is obviously necessary to expand the viscous terms,i.e.viscous force,rate of work done by viscous stress and dissipation,in basic aerodynamic equations in the non-orthogonal curvilinear system[2].However,each of these expansions consistes of tens or even hundreds of algebraic terms.The expansions of these three viscous terms discribed in this paper are considerably simplified by analysing their order of magnitude.