Ultrasonic Turbulence Strengthen And Expreimental Studies Based On The Soft Abrasive Flow Machining

Soft Abrasive Flow Machining (SAFM) is a new method using abrasive flow which is in turbulence state to process parts. According to some deficiencies with this processing method such as:the uneven distribution processing in the machining resulting in dead angle appears cause by the uneven distribution of turbulent kinetic energy and dynamic pressure; the partial processing time, low processing efficiency, proposing a new method of the ultrasonic excitation technology application of solid-liquid two-phase soft abrasive flow machining. This method can enhancement turbulence through disturbance flow field, so as to improves these shortcoming, realize the optimization of the soft abrasive flow precision machining. The main conclusions are described as follows:(1) Based on the particle dynamics and solid-liquid two-phase flow theory, discussed the impact of the turbulence field to abrasive flow and micro cutting mechanism of SAFM to the heteromorphous surfaces. Numerical simulation on the basis of the above study, the basic model of the solid-liquid two-phase flow and its characteristics were described and analyzed, select the physical model and turbulence field model.(2) Based on the method of SAFM loaded with ultrasonic excitation, studied the impact of ultrasonic excitation on the SAFM. In consideration of the complicated of flow state in SAFM, the impact of ultrasonic excitation is simplified. According to the ultrasonic cavitation and SAFM wall friction, the chosen Realizable k-s model is modified and the appropriate simulation model is designed.(3) On the basis of Realizable k-s model and Mixture model, a dynamic model of SAFM process was established for concrete condition of constrained flow passages. The pressure, velocity and turbulence kinetic energy distribution in different moment were got through a large number of simulation. Get some results through Comparative Case Study with the distribution of steady flow.(4) Completed the experiment study by putting up the experimental platform for soft abrasive SAFM and designing ultrasonic excitation load constraint module. Machining experiments show that this method can indeed achieve improved processing efficiency and quality, restrain SAFM’s over-processing in high efficient processing area and eliminate dead angle appears, meanwhile, proved the validity of the above simulation method.