Turbulent cavitating flow in the nozzle of a fuel injector for diesel engines strongly affects the atomization process of the injected spray.It was clarified that a cavitation cloud in a vortex shed from the tail of the cavitation near the nozzle exit finally induces the large deformation and disintegration of the discharged liquid jet.A popular approach to numerically model the cavitating flow is the Homogeneous Equilibrium Model(HEM)with the Mass Transfer Model(MTM),which is sometimes called the Volume-Of-Fluid(VOF)method without interface reconstruction.The source terms for MTM are often given by Bubble Dynamics Model(BDM)especially using Rayleigh(R)equation based on the vapor saturation pressure Pv.We have found that R equation over-predicts cavitation when local pressure is slightly below Pv.Therefore,we have proposed the Modified Rayleigh(MR)equation based on the critical pressure Pc.In this study,the applicability of the MR equation with various turbulence models to turbulent cavitating flows in a rectangular nozzle of 2 mm in width is examined.Whether we can simulate cavitation cloud shedding process or not and can quantitatively predict the cavitation length and thickness using OpenFOAM are investigated.The two-equation turbulence models within the framework of RANS,such as k-ω SST and RNG k-ε models with various meshes of different cell sizes and one equation eddy viscosity model under the framework of Large Eddy Simulation(LES)are tested to simulate the turbulent flow in the nozzle,whose liquid velocity was measured by Laser Doppler Velocimetry(LDV).The results conclude that(1)R equation over predicts cavitation length,while MR equation together with appropriate turbulence model and a fine mesh can simulate the complex cavitating recirculation flow and cloud cavitation shedding.(2)RNG k-ε model with a fine mesh of about 25-50 μm in the minimum mesh size Δxmin,k-ω SST model with a finer mesh of 25 μm in Δxmin and LES model with a finer mesh of 4.4 μm in Δxmin give a good prediction for the turbulent cavitating flow in the nozzle.