Investigation of viscosity effect on velocity profile and cavitation formationin diesel injector nozzle

The effect of cavitation inside real diesel injector nozzle is challenging both theoretically and experimentally,since it is characterized by large pressure gradient and small orifice geometry. A mixture based model in Ansysfluent v14 were performed for the simulation. Simulation is validated using available two‐phase nozzle flow data.Simulation was performed with finite volume method and simple algorithm. From three cavitation model that isavailable in Ansys fluent v14( 1‐ Schnerr and Sauerr cavitation model, 2‐ Zwart gerber belamri cavitation model3‐ Singhal cavitation model), Our simulation were perform with Singhal cavitation model because the other twomodels were not capable in predicting choke condition at all. Validation for several parameters such as massflow rate and velocity profile was performed. At the end our main focus was toward the effect of viscosity oncavitation formation and velocity profile in nozzle’s throttle. Several simulations have been conducted withdifferent software such openfoam but none of them could precisely predict mass flow rate in choke condition.Our simulation was capable of predicting mass flow rate choke condition with 1.9% error from experimentaldata.

کلیدواژه ها:

cavitation ، injection nozzle ، chokes flow ، modeling ، and two‐phase flow