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Fuel spray atomization strongly affects engine economic performance and emissions, which in turn is significantly influenced by nozzle cavitation phenomenon with high injection pressure in diesel and GDI engine. A new cavitation model named “nozzle cavitation model” was presented to specifically simulate nozzle cavitation while the corresponding visual experiment was made to validate this model. The presented model considered phase change, bubble dynamics, turbulent pressure fluctuations and noncondensable gases while the equation of phase-change rate was amended by cavitation number. The comparison of simulation results with “nozzle cavitation model”, simulation results with Schnerr—Sauer cavitation model and visual experimental results showed that the development trend of nozzle cavitation from “nozzle cavitation model” and Schnerr—Sauer cavitation model both agreed well with experimental results, that was, the normalized cavitation length was increased with the enhancement of injection pressure and the maximal increase appeared on the transition from development cavitation to super cavitation. The normalized cavitation length from “nozzle cavitation model” agreed well with experimental results while that from Schnerr—Sauer cavitation model was obviously less than that of experimental results. The maximum errors of normalized cavitation length simulated with the two cavitation models both appeared at super cavitation stage, which were 8% with “nozzle cavitation model” and 35% with Schnerr—Sauer cavitation model. The conclusion that the predictive capability of “nozzle cavitation model” was superior to that of Schnerr—Sauer cavitation model for simulation of nozzle cavitation was mainly because of the turbulent viscosity in near-wall region calculated from the former was lower than that from the latter, the threshold pressure value to produce phase change from the former was higher than that from the latter, the bubble number density from the former was amended by volume fraction of noncondensable gases and the equation of phase-change rate from the former was amended by cavitation number.