Abstract:An improved way of single channel impeller hydraulic design is discussed in this paper, it is more simple than the former design method, which is especially fit to program CAD software. Based on summing up many excellent hydraulic models of single channel impeller, it gives various kinds of coefficient values of axial section. Inspect the design way of plan hydraulic design of double channel impeller, it provides the new design way of plan hydraulic of single channel impeller. It introduces a new change ruler of section area and an equation of plan channel midline. At last, a programming way and an example of design are given.