Numerical prediction of potential cavitation erosion in fuel injectors

Flow devices, like throttle and nozzles often encounter huge pressure drops, sometimes much below the saturation pressures. This leads to the occurrence of cavitation with vapor and bubble generation. Once the bubble gets transported to high pressure regions in the downstream, it collapses, often near the metal surface with huge imploding pressure leading to the rupture and erosion of the components. This paper presents a CFD based numerical technique to predict potential erosion due to cavitation. Predicting the zone of cavitation erosion is rendered possible by efficiently capturing the periodic vapor cloud shedding and collapse. Suitable algorithm was adopted to detect collapse pressure which can potentially lead to material erosion due to cavitation. Numerical prediction of potential sites of cavitation erosion was validated against experimental work. Thus this method is expected to be useful in reducing the design cycle time of fuel injectors.