Question: Continuity equation for two-dimensional flow in polar coordinates
(a) Consider a two-dimensional flow field expressed in terms of the cylindrical coordinate system (r, ?, z), where all flow variables are independent of the azimuthal angle ?-for example, the flow over a circular cylinder. If the velocity components (u, v) correspond to the coordinate directions (r, ?), respectively, show that the continuity equation is given by
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(b) Show that the continuity equation can be automatically satisfied by a stream function ψ of a form such that
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