| Taking aim at the problem of severe wear and tears of machine parts in solid-liquid two-phase flow, and by collecting relevant information, consulting related documents, I understand that we should study the problem from the flowing angle of solid-liquid tow-phase flow , during the course of investigation and researching the influential factors about wear and tears all over the world. So the boundary-layer flow over flow-passage components in the silt-laden flow is investigated by association of the two-phase flow theory and boundary-layer theory , the latter being closely related with the phenomenon of hydraulic wear and tear .The mathematical model of relevant boundary-layer flow is developed , and then a numerical calculation is gone on to it. Major investigation work is as follows: (I) Developing a mathematical model of boundary-layer in solidæ¢iquid two-phase flow according to the kinematics of two-phase flow and boundary-layer theory. (2) Developing a set of generation program of body-attached coordinate system with a broader generality , which can transform an irregular physical domain into a regular one for convenience of computation. (3) Presenting a numerical method for the solution of boundary-layer equation. (4) Verifying the validity of boundary-layer model by means of computing the flow within boundary-layer over a plate , then computing that over a isolated airfoil so that the distribution of velocity ,concentration , and pressure of the flow is attained and the abrasion characteristics can be analyzed subsequently. The result show that the numerical model is rational , which offer a new way for analysis of hydraulic abrasion mechanism ,determination of hydraulic losses, and design of reasonable and efficient wear-resistant hydraulic machinery component. |
