Thrombosis caused by all kinds of cardiovascular diseases, has been influencing people's health. In a blocked blood vessel, pulsation flows have a positive effect on thrombus. Because of the blood viscosity and the inertias of red blood cells and the fluid, the frequency of pulsation flow influences the effect of dredge blood clots. Under the condition of low differential pressure, conduction of the another flow pipe reducing the pressure variation causes the effect of dredging blood clots not to be ideal in the bifurcated pipe model. So we will increase the differential pressure and improve the amplitude of pulsation flow, reduce the influence of the conduction effect of expedite tube, then study the effect of dredge blood clots which is caused by the pulsation flow in the bifurcated pipe. We find that low frequency pulsation flow has a good effect on dredge blood clots for a long time. Relatively, high frequency pulsation flow needs less time, but the effect of dredge blood clots is not obvious if the frequency is higher than a certain value. The friction between cells and the walls of the tube also has an effect on dredge blood clots.