Prediction Methods for Turbulent Incompressible Flow in Conical Diffusers

摘要

The aim of the study is to provide a method which is capable of predicting the entire mean-velocity field in a conical diffuser when the inlet velocity field is turbulent, incompressible, and completely specified. The desired prediction method is divided into two phases. In the first phase, a method for predicting the growth of the displacement and momentum thicknesses is considered. For the known straight-walled conical configuration, the value of the displacement thickness is sufficient to specify the freestream velocity at any point along the axis of the diffuser. Therefore, in the second phase, a method for predicting the velocity profile in the boundary layer using the integral parameters and the free-stream velocity is considered. Several prediction methods to forecast the growth of the integral parameters are proposed. The conical diffuser data from the literature is used as a means for evaluating the applicability of the proposed methods. (Author)