旋转射流的流动物理

he physical model and differential equations of the trajectory of free swirl jet is put forward initiatively. The model is based on the force analysis to an infinitesimal element, on which the continue swirl jet circle is divided into a series of tiny jet bundle flown as helix. Meanwhile, a new method to treat with the trace of the streamer is used, that is divided into two steps: one step let the trajectory in space decompose to two projections on the vertical plane and reconstruct a space trajectory by best-fit the photograph of the trace, second step is extended to all bundles according to their symmetry.