1、重慶大學(xué)碩士學(xué)位論文前混合振蕩磨料射流流體動(dòng)力這及切割實(shí)驗(yàn)研究姓名：朱勇申請學(xué)位級(jí)別：碩士專業(yè)：車輛工程指導(dǎo)教師：李曉紅2001.5.1!!堡塑!望!g堡!望!!i!!!蘭!!!鯉!!g竺!!蘭豎!型壘呈!!墾皇!!ABSTRACTBaseelonthetheoriesoftransientflowsandfluidnatworkthemodeJofapremixedOscillationAbrasiveWaterJetispresen

2、tedThefrequencycharacteristics，abrasives’oscillatingaccelerationandpenetrationabilitiesarestudiedemphaticallyAndtheparametersofstructure，fluidandoperationareoptimizedbymeansofexperimentsSolutionspresentedinthethesisCanbe

3、summarizedasfollows：1)Inthevalidoscillatingconditionsofapre—mixedOscillationAbrasive，smalldisturbedwavescausedbyinstabilitiesoftheshearlayerofthewaterjetareproducedandenlargedcontinuallyandformapulsedabrasivewaterjetwith

4、aseriesofobviouslargescalestructuresandabrasiveclusters2)Theoscillatingfrequenciesaredeterminedbythewavespeed，thecompositionofthefluidandstructuralparameters3)Thewavespeedsaredeterminedbythecompositionofthefluid，anddecre

5、aserapidlywithgasvolumeconcentrationincrease4)ThefrequencycharacteristicsofapremixedOscillationnozzle，beingobviouslyinfluencedbytheparametersofstructureandfluids，havenonlinearperformancesofresonantorandlowpassfilter51The

6、velocityofoscillatingabrasiveparticlesisnearlyassameasthejetflow，6)TheoptimumstructureofapremixedOscillationAbraiseWaterJetnozzleisconcavecollisionwallthediameterratioof也edownstreamnozzleVSupstreamnozzleisinrangeof1214th

7、eratiooftheoscillationchamberlengthVSthedownstreamnozzlediameterisinrangeof1577)Thecuttingdepthofpre—mixedOscillationAbraiseWaterJetintherocksisabout140167timesofpremixedabrasivewaterjets，andstandoffdistancesbecamelonger