A two-equatioo tin'huh, nee model has beeo dereloped for predicting two-p/rose flow. The two equations describe the conservation of turbulem'e kinetic energy and dLs'sipation rate of that em'rgy ./br the incompi'essibk, carrier fhd d ht a two-phase flow. The'continuity, the momenttmr, K and e equations are modeled, hi this model, the solid-liquid slip veh~cities, the l~artiele-I)artic# h;teractions ond the interaetioos between two phases are ~'onsldered. The sandy Water pipe turbulent flows are sucecssjidly predicted hr this turbuh, nce model.

The forces on rigid particles moving in relation to fluid having been studied and the equation of modifications of their expressions under different flow conditions discussed, a general form of equation for discrete particles' motion in arbitrary flow field is obtained. The mathematical features of the linear form of the equation are clarified and analytical solution of the linearized equation is gotten by means of Laplace transform. According to above theoretical results, the effects of particles' properties on its motion in several typicalflow field are studied, with some meaningful conclusions being reached.