VISCOELASTIC FLOW PAST A WEDGE WITH A SOLUBLE COATING.

The steady, two dimensional, incompressible flow of a viscoelastic fluid past a wedge of 90 degrees coated with the viscoelastic material is studied theoretically using constitutive equations proposed by Oldroyd in 1958. The effect of diffusion of the coating as well as its material properties viscosity, relaxation time, retardation time, etc. on the frictional force is investigated. A boundary layer analysis is performed on the constitutive equations as well as the momentum equations consequently, the constitutive equations give the dimensionless shear stress. A similarity transformation is found for the set of boundary layer equations. Series expansions and the method of steepest descent are employed to obtain the solution in the asymptotic series of gamma functions. Results indicate 1 the thinner displacement thickness does not necessarily imply a larger frictional force for the viscoelastic flow and 2 for a homogeneous viscoelastic flow, the frictional force increases as the degree of dilatancy of the material increases, and decreases with increasing degree of pseudoplasticity of the material. Author