Abstract:Numerical simulation of the jet flow field with different orifice parameters of deflector jet valve by using CFD software was carried out. The jet velocity and pressure distribution characteristics of deflector jet valve and the influence law of different orifice parameters D1, L1, D2, L2 on jet velocity and pressure were obtained. It is found that the maximum value of the jet velocity from the nozzle is gradually decreased and then increased to the 08 mm position after the nozzle jet velocity; The jet pressure increases at first and then decreases to a smaller value at the 08 mm position, finally, the maximum value is reached at the valve body of two receiving port. The D1 plays a decisive role in jet flow of the V type diversion port, jet pressure and recovery pressure difference. The upward shift of jet velocity curve and the downward shift of jet pressure curve when increasing D2. The L1 has effect on the jet pressure, however the influence of L2 on the jet field can be neglected. The research results can provide reference for the engineering design and optimization of high performance deflector jet servo valve.