We consider unsteady flow of the viscous incompressible fluid. This flow is caused by the sudden motion of the dihedral angle with the constant velocity in the fluid being at rest.
It is assumed, that the angle moves in the direction
of the edge and the flow is layered. This flow simulates roughly a boundary layer in the neighborhood of the intersection a wing and fuselage of a aircraft at a distance from the leading and trailing edges of the wing.
In the case right dihedral angle, we obtain the analytic solution of the considered problem; while in the case of arbitrary angle, we reduce the problem for a function of three independent variables to a boundary value problem for an ordinary differential equation.
We use the power geometry methods.
Mathematical problems and theory of numerical methods