Numerical Simulation And Research Of The Internal Flow Pattern Based On Working Conditon Of Hydraulic Impactor

As an efficient tool, Hydraulic impactor job is in great demand that has been widelyused in housing demolition, road repair, mining and other industries. However, the share ofdomestic hydraulic impactor is low owning to many factors such as its late start, lowyield and unstable performance. Therefore, it is of great theoretical and practical values tostudy numerical simulation and research of the internal flow pattern of hydraulic impactorthat based on working condition.From the perspective of testing cars in practice and establishing models ofone-dimensional and three-dimensional, this thesis investigate its performances thatprovides a reference for improving the performance of hydraulic impactor according todomestic and overseas study. Firstly, the characteristics of the impactor motion aresummarized through describing the mathematical model of hydraulic impactor, obtainingthe solutions by matlab, testing cars in practice under different conditions of impactor,which lays a foundation for the validation of simulation model. The one-dimensionalsimulation model is built in flowmaster that can validate the matching of automotivefacilities and its influence on key system parameters quickly and accurately key systemparameters include the displacement, flow, pressure, etc.Comparing each key parameter characteristics of the impactor under different work-ing conditions and extracting the boundary value of one dimensional model of hydraulicimpactor under some conditions in order to provide boundary conditions forthree-dimensional CFD simulation model. Finally, the three-dimensional modeling of thehydraulic flow field is extracted in CATIA and is imported into PumpLinx for meshing andloading boundary conditions in order to complete the internal flow field simulation analysis of compactor. Then we can conclude distribution features of internal flow field ofa hydraulic impactor under the condition of position of three typical moments such as atthe beginning of the return trip, reversing valve, and the stroke times. After that we cananalysis and point out the key structure that affect the distribution of flow field. Whichprovide the reference for improving the performance of the impactor.The simulation results show that it is necessary to add a buffer device which can bestudied in the one-dimensional simulation model as the impact is always in high frequencymotion and volatility in the flow field. As the connections between each channel and thecorresponding oil chamber is in unstable in flow field, it is necessary to deal with it fromthe angle of the structure for processing, such as appropriate chamfering. As cavitationmay occur in the chamber wall near the oil passage, The selection of material for cylinderneeds a overall consideration of factors that include the material cost and intensity factors.