SWIRLING FLOW IN CIRCULAR PIPES.

An analysis is made of swirling flows in straight circular pipes. It is shown that the swirling and axial component of the velocities can be expressed as functions of the swirl intensity, defined by the ratio of the angular momentum flux to the axial momentum flux. The swirl velocity may, in general, be momentum flux. The swirl velocity may, in general, be expressed as the sum of velocities due to a forced vortex motion and a free vortex motion. The axial velocities can be calculated by equating the pressure drop along the pipe axis to the turbulent axial stress.