On swirling jets

An exact solution to the Navier-Stokes equations is found for a jet emanating from the end of a vortex filament into a region filled with a fluid. Depending on the degree of swirling of the jet, a closed or open flow regime is realized. In the case of strong swirling, the solution is not unique. Approximate analytic solutions to problems as well as numerical solutions are given.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 1, pp. 26–35, January–February, 1979.I am grateful to M. Kh. Pravdin for the numerical calculations.