Abstract: | A numerical method of calculating the unsteady aerodynamic characteristics of a helicopter lifting rotor smoothly enveloped by an air gust arriving from an arbitrary direction is proposed. The problem is solved in the non-linear formulation for an incompressible medium. The flow over each blade is simulated by a system of discrete vortices. The deformation of the vortex trail from the blades under the influence of the gust is taken into account. The results of the calculations are reported.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 2, pp. 153–158, March–April, 1987. |