| Though with the rapid development of Marine exploitation and underwater engineering technology, AWJ cutting technology under high confining pressure has been applied widely overseas, it is still in the stage of experiment research in domestic country.This paper has systemically researched mechanism and model of AWJ under high confining pressure, and set up the ANFIS fussy system modeling structure of AWJ under high confining pressure, and analyzed the rule and relation of cutting performance and the parameters of AWJ under high confining pressure by using self-designed experimental devices to simulate high confining pressure, and the effect of different confining pressure on performance of AWJ. According to theory analysis and experiment research, we gamed the following main conclusions:(1) For liquid-solid two-phase flow, its turbulence diffusion effect includes the exchange of particles' momentum and exchange liquid-phase and solid-phase mediums' momentum that is main way by which solid-phase medium gain kinetic energy.Under the confining pressure, axial velocity of water jet velocity decreases exponentially with time because of the existence of attenuation coefficient ' , and attenuation coefficient is caused by the resistance of environmental medium between nozzle and material under confining pressure.Axial dynamic pressure of water jet under high confining pressure decreases faster than that does under no confining pressure; the stand-off distance under high confining pressure is a key factor to the loss of fluctuating pressure.(2)AWJ is a type of fluid-grinding cutting process, AWJ deflects and fractures when kerfs depth increasing, upside of the stand-off object's cutting surface is the section of smooth cutting grinding, downside is the section of grind by eroding formation. The appearance of cutting surface is affected by parameters of cutting process periodically.(3)) Based on the ANFIS fussy modeling platform and experiment data simulating AWJ under high confining pressure, according to the selected input and output properties, modeling structure of AWJ under high confining pressure is established.Comparing the fussy output and the data of experiment, it is found out that the fussy output based on ANFIS can reflect the rule and trend of experiment data. The fussy model based on ANFIS is based on lots of data experiment simulating AWJ under high confining pressure, and is established according to factual parameter's enactment, thestrategy has more veracity, reliability and fault-tolerance than the traditional experiential and regressive model.(4) Under high confining pressure, kerfs depth H decreases by segment with the increase of ratio of stand-off distance to diameter of nozzle (Sv/d), which shows the existence of a valid ratio of stand-off distance to diameter of nozzle (Sv/d). And with increase of confining pressure, the performance of AWJ deceases obviously.(5) AWJ's initial several (4-8) cutting processes predominately, when cutting repeatedly under high confining pressure.(6) AWJ's most optimal transversal velocity (v) is between 4 and 7 mm/s, considering both efficiency and effect of cutting, under high confining pressure.(7) AWJ's impact cutting performance and kerfs depth (H) increase along with increase of density of abrasive (ma) under high confining pressure. Amplitude of kerfs depth (H) along with increase of density of abrasive (ma) is much more less correspondingly than when confining pressure (pe) is very high. It is very important to the application of AWJ in Marine deepwater engineering.(8) Under high confining pressure, AWJ's systemic pressure (nozzle's jet pressure) reflects the initial jet velocity of AWJ directly. When AWJ's systemic pressure excesses threshold pressure, kerfs depth increases along with increase of AWJ's systemic pressure linearly.(9) When ratio of stand-off distance to diameter of nozzle (Sv/d) is less than valid ratio of stand-off distance to diameter of nozzle, AWJ's kerfs depth attenuates along with increase of confining pressure ra...
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