| Along with the development of new material technology, the solid material smashing had been proposed more and more high reques. At present, the traditional smashing methods have a lot of questions, such as energy consumption is high, cannot maintain the primitive crystallization shape of the pellet and superficially attractive, obtains high grade, high-purity materials is difficult. The high-pressured waterjet technology is precisely development a new technology which slove these requests.This paper has designed one kind of new compound waterjet ultrafine grinding installment which was used high-pressured waterjet technology as existing foundation. This device will smash the added particles by letting them have high-pressured current of water the water wedge function and the high-pressured current of water iMPact function, the function with the acceleration pipeline between frictions, with collision iMPact function between target bodies, with the function of the grinding medium, the iMPact function in water body turbulent, the function of cavitations and so on. The power supply used high pressure plunger pump which the biggest working pressure is17MPa, the experiment accelerating tube is used the D60 seamless steel pipe, selected the self-absorption type feeding method, and has maded the visible optimized improvement on the installment.Considered that the material easy to obtain as well as coMPate to the high-pressured waterjet smashing, this article selects the coal to the experiment material. At 12MPa,15MPa and 17MPa working pressure, in the same input speed, conducted a series of smashing experimental study. The experimental result had indicated that under the same input speed, because the working pressure was bigger, the total material shatter index was bigger too, obtained the tendency of various rank material shatter index also increases. Increased the pressure to enhance second-level (0.5mm～0.1mm) and the third-level (0.1mm～0.05mm) material shatter index is obvious, therefore the enhancement working pressure was important technical way to raises the shatter index. The experiment also aimed to do the series research under the identical working pressure (17MPa) and the different input speed, and analysed the influence of shatter index. Finally indicated that the influence of all levels material shatter index is obvious which is on different input speed. The overall performance was slower for the input speed, the total shatter index to be higher, all levels of material shatter index also correspondingly enhanced, first-level and the third-level material shatter index is been most remarkable influence which is on different input speed, increased the scope is big.Using the FLUENT software has carried on the three phase numerical simulation to the compound waterjet installment which in the spray nozzle to the iMPact target body place, mainly auxiliary solves with the finite volume method by the RNG model, use the VOF model, the solids (coal grain) interaction with continuous phase use discreat phase model. Analyzed the hydraulic characteristic in the box, just like speed of flow, pressure, granule characteristics and so on. The simulation discovered that the solid beaming is good in theD40 accelerating tube, a target body impact pressure is bigger, and therefore the suitable accelerating tube could obtain a higher shatter index. Through the numerical simulation under the pressure of 12MPa, 15MPa,17MPa, discovered that in the situation of working pressure increases, the target iMPact pressure also increases, the pressure is used in the iMPact crushing also to increase, namely the material shatter index is higher.Through contrastive analysis research on the experimental result and the numerical simulation result, both tally basically.
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