Effect of Acoustic Chamber Length on Disintegration of Ductile Material with Pulsating Water Jet

Pulsating water jet is a hybrid process of ultrasonic machining and waterjet machining. The continuous jet of the water is induced with ultrasonic disturbances resulting in forced breakup of the jet. The morphology of the jet is stimulated by ultrasonic transducer depend upon the frequency and power transmission. The transmission of the fluctuations is influenced by variation in acoustic chamber length which in turn leads to variation in disintegration depth. Acoustic chamber is a space where the inlet water from the pump is induced with the ultrasonic fluctuations generated by the ultrasonic sonotrode. Acoustic chamber length is varied for tuning the system to generate maximum output power transmission with specific input conditions. In the present study, the acoustic chamber length is changed from 5 mm to 22 mm with inlet water pressure kept constant at 30 MPa. An inclined trajectory starting with standoff distance 5 mm till 101 mm at an angle of 16˚ with traverse speed of 1 mm/s is used. 18 experimental runs are conducted, and all the grooves created by the impact of pulsating water jet were measured and plotted for observing the influence of acoustic chamber length with varying standoff distance. Surface morphology of the eroded grooves were studied using SEM images which showed surface features such as voids, cavities, micro-channels and upheaved surfaces along the periphery of the grooves.