The mechanism of blood embolism formation always attracts the attention of researchers. Through calculating rigid particle movement in a bifurcated pipe, the blood flow as well as blood embolism in a bifurcated pipe are simulated preliminarily, and the flow speed and the probability to form thrombus are investigated. We can draw a conclusion that the higher the hematocrit is, the easier the blood is to form embolism, meanwhile, the bigger the pressure difference, the harder the blood is to form embolism. We also find that the embolism tends to occur at the entrance of a bifurcated pipe and bifurcation forming place. Beyond the bifurcation place, the hematocrit of the blood in a big tube is larger than that in a small tube.

Based on the lattice Boltzmann method, the motion of single suspended particle in tapered tube is simulated numerically. The distributions of velocity and pressure in the flow field are obtained. The hydrodynamic force on the particle boundary is evaluated by conventional momentum exchange method (CME), lattice-type-dependent momentum-exchange method (LME) and stress tensor integral method (STI) separately. The variations of velocity and the trajectory of the particle which starts at different places are analyzed, the results evaluated by LME are in excellent agreement with those by STI and the results evaluated by CME are slightly different from those by the former two methods.

Lattice Boltzmann method is used to study fluids in a bifurcated tube composed of tubes with different diameters.The flow velocity,streamline distribution and the trajectory of single particle in the bifurcated tube are analyzed for the fulture study on blood flow in the bifurcated tube.

A lattice Boltzmann model of two-dimensions is used to simulate the movement of rigid suspended particle in a pulsating flow in micro vessel.The particle is as big as a red blood cell,and the micro vessel is four times as wide as the diameter of the particle.The plasma is viewed as Newtonian flow,and the hydrodynamic force is calculated by integrating the stress tensor on the boundary of it.It is found that Segre-Silberberg effect does not present when the flow velocity is on the same level with human blood,and it only presents when the flow velocity is increased to a rather high level.During the increase of flow velocity,the change of equilibrium position is seen to be not continuous but discrete,showing differen from the characteristic of the drift in macro flow,which reveals the dynamics transition from micro flow to macro flow.