ИСТИНА

The 3-D Neumann boundary value problem for the Laplace equation out of the body of small thickness is considered. An approach is proposed to solve the problem in which the boundary conditions are transferred to the middle surface of the body. As a result, a new boundary value problem on the screen (the middle of the body surface) is solved. The initial shape of the body is taken into account using the corresponding boundary conditions. The resulting boundary value problem on the screen is reduced to a system of boundary integral equations with singular and hypersingular integrals. These integral equations are solved numerically using the methods of piecewise constant approximations and collocation. On the basis of the developed approach a new version of the panel method for solving the problem of ow past wing is built using the wing replacement with the middle surface. The numerical tests showed that the reduction of the wing thickness does not decrease the accuracy of the numerical results. The proposed method is applied to the problem of ow around a gliding parachute and the calculation of its shape.