2.9.1 uxx+uyy+βxux=0

problem number 95

Added June 20, 2019

Taken from http://people.maths.ox.ac.uk/chengq/outreach/The%20Tricomi%20Equation.pdf

Solve for u(x,y) uxx+uyy+βxux=0

Mathematica

ClearAll["Global`*"]; 
pde =  D[u[x, y], {x, 2}] + D[u[x, y], {y, 2}] + beta/x*D[u[x,y],x] == 0; 
sol =  AbsoluteTiming[TimeConstrained[DSolve[pde, u[x, y], {x, y}, Assumptions->beta>0], 60*10]];
 

Failed

Maple

restart; 
pde := diff(u(x,y),x$2)+ diff(u(x,y),y$2) + beta/x*diff(u(x,y),x)=0; 
cpu_time := timelimit(60*10,CodeTools[Usage](assign('sol',pdsolve(pde,u(x,y),'build') assuming beta>0),output='realtime'));
 

u(x,y)=(c1BesselJ(β212,_c1x)+c2BesselY(β212,_c1x))(c3sin(y_c1)+c4cos(y_c1))xxβ2

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