?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.relation=http%3A%2F%2Fmiis.maths.ox.ac.uk%2Fmiis%2F58%2F&rft.title=Fracturing+rock+with+ultra+high+pressure+water&rft.creator=Fitt%2C+A.D.&rft.creator=Fowkes%2C+N.D.&rft.creator=Mason%2C+D.P.&rft.creator=Myers%2C+T.G.&rft.creator=Moss%2C+E.A.&rft.creator=Cheng%2C+J.&rft.subject=Energy+and+utilities&rft.subject=Materials&rft.description=Modelling+issues+are+considered+for+the+process+of+cracking+rock+in+mines+using+ultra+high+pressure+water.+The+elevated+pressures+are+caused+by+the+ignition+of+a+propellant+and+may+be+as+large+as+1000MPa.+We+first+consider+time%2C+length+and+pressure+scales+and+then+derive+a+model+for+the+propagation+of+a+two-dimensional+crack.+A+number+of+aspects+of+this+model+are+considered+and+similarity+solutions+and+behaviour+near+the+crack+tip+are+investigated.+Consideration+is+given+to+a+simplified+model+where+the+elastic+component+of+the+interaction+between+the+rock+and+the+fluid+is+handled+using+an+elementary+closure+law%3A+in+this+case+much+progress+may+be+made+and+closed-form+solutions+may+be+determined.+Conditions+are+also+identified+where+a+model+based+on+%E2%80%9Cimpulsive%E2%80%9D+lubrication+theory+is+appropriate.+However%2C+this+leads+to+a+very+challenging+problem.+Finally%2C+some+other+ways+of+extending+the+model+to+include+(for+example)+fluid+leak-off+into+the+rock+are+discussed.&rft.date=2004&rft.type=Study+Group+Report&rft.type=NonPeerReviewed&rft.format=application%2Fpdf&rft.language=en&rft.identifier=http%3A%2F%2Fmiis.maths.ox.ac.uk%2Fmiis%2F58%2F1%2Fcracksv5.pdf&rft.identifier=++Fitt%2C+A.D.+and+Fowkes%2C+N.D.+and+Mason%2C+D.P.+and+Myers%2C+T.G.+and+Moss%2C+E.A.+and+Cheng%2C+J.++(2004)+Fracturing+rock+with+ultra+high+pressure+water.++%5BStudy+Group+Report%5D+++++