Study on jet flow development integrating with initial region

Having a potential core, the velocity profile in initial zone of incompressible submerged jet flow is different from that in fully developed region. In the previous researches, the two regions were studied separately, and a short part between the two regions was considered as a transition one. The velocity profile in fully developed region looks as a Gaussian distribution, which is valid when jet initial region is relatively short. But when the size of initial zone is long enough and can not be neglected, especially for large-size exit, such as the ship propeller jet, this treatment is unreliable. Based on the analysis of flow structure of jet flow, a new velocity profile formula of submerged jet flow was proposed, which combines the initial, transition,and fully developed regions of jet flow via modifying Gaussian distribution with a radial adjusting coefficient. The new formula agrees with the observations of continuous flow.