BRY air-cooled centrifugal heat pump impeller size of how to determine

In BRY air-cooled centrifugal heat transfer oil pump design, generally need to give the design parameters: flow Q, head H, speed N, NPSHr NPSHr and efficiency. According to the above parameters, the structural scheme of the centrifugal tip can be initially determined and the specific rotational speed Ns of the impeller can be calculated. Then, some empirical data (formulas) are used to determine the main geometric dimensions of the impeller.

In BRY air-cooled centrifugal heat transfer oil pump and Francis pump impeller oil flow design, assuming that the flow inside the impeller is axisymmetric flow, the velocity at any point in the flow field can be decomposed into axial (including the axis of the impeller axis) Of the axial velocity component and the circumferential velocity component. The distribution of the axial velocity component is determined by the axial projection of the impeller runner and the boundary conditions at the inlet of the impeller. The distribution of the circumferential velocity is determined by the distribution of the axial velocity component and the blade placement angle. Therefore, the first step in the design of the impeller is to determine the axial velocity and circumferential velocity. BRY air cooled centrifugal heat pump impeller size to determine the following three methods:

(1) model conversion method. The method is simple and reliable. The specific method is the first one with the BRY air-cooled centrifugal heat transfer oil pump is similar to all parts of the flow of its geometric size to zoom in or out. Botou City Taibang Valve Manufacturing Co., Ltd.

(2) speed coefficient method. Speed ​​factor method is essentially a similar design method, compared with the model conversion method, the difference is that it is based on a series of similar BRY air-cooled centrifugal heat transfer oil pump based on, rather than on a similar BRY air-cooled Centrifugal heat transfer oil pump based on. In other words, the speed coefficient method is based on the principle of similarity, the use of a series of excellent BRY air-cooled centrifugal heat transfer oil pump calculation of the main factor impeller size.

(3) Theoretical calculation method. The method based on the basic equations of the vane pump, the impeller diameter and blade outlet angle more accurate calculation, usually require iterative calculations.