Effect of Needle Height on Formation of Cavitation in a Six-Hole Diesel Injector Nozzle

In this study cavitation is investigated in a real size nozzle. At first the flow is mathematically modeled using Reynolds Stress Navier Stokes (RANS) set of equations. Two different turbulent approaches were also investigated in this study and it was found that the K- ɛ turbulence model has a better accuracy comparing to the K- ɯ when investigated numerically and compared with Winklhofer experimental data. After verifying the result using Winklhofer rectangular shape nozzle and mass flow rate approach, a real size nozzle is simulated and cavitation phenomena is investigated separately. At this point, one boundary condition is used and effect of different needle heights were also investigated. It was found that increasing needle height increases length of cavitation at the beginning but after a while any further increase in value of the needle height would not change formation of cavitation significantly.

کلیدواژه ها:

Cavitation ، Diesel Injector Nozzle ، Shnerr-Sauer ، Vapor Volume Fraction ، K-Epsilon