The plane steady problem of flow past a body by stream of an ideal incompressible fluid is considered. The idea to simulate complicated flows using the part of flow transition to the second sheet of Riemann surface, similarly to D. A. Efros’ classical scheme or Shurygin's models, is evolved. The special method for flows analysis is worked out: the whole flow area is broken up standard fragments (homotopy areas) consisting from homotopic to each other streamlines and gluing along their common boundaries. The homotopy areas gluing character is defined by location of stagnation points. All flow schemes for problem of flow past a pair of aerofoils, i.e. for Riemann surface of genus one (torus), are considered on this basis.