Solving ODE with boundary conditions

Question

Delika Weragoda 2022-12-7

0
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https://ww2.mathworks.cn/matlabcentral/answers/1873432-solving-ode-with-boundary-conditions

编辑： Torsten 2022-12-7

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Is there a way to solve the following ODE with the boundary conditions?

All other parameters A, B, C, D and n are constants.

I tried using bvp4c, but I get an error for incorrect dimensions for raising a matrix power. Did convert all raising power and operation (* and /) using the elementwise operation, but still am unable to get a numerical solution. Would appreciate some guidance. The code I used is given below

Not sure if this is the way to solve this type of ode, if there are alternative ways to get a numerical solution that would be great.

Many thanks

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clc;
clear;
close all;
A = 6.14e-4;
B = -9.4e3;
C = 2.14;
D = 6.72e3
n = 3
yf = 0.3; %Y upper limit 
%s0 = 1 - ((C/D)^(1/(n+1))); %calculate the initial values for y = 0
H = ((C/D)^(1/(n+1))) %Function to be subtracted above, for BC at y=0
f = @(y, s) ((A*y + B*s^n)/(n*C + D*(1-s)^(n+1)))*(((1-s)^(n+1))/s^n) %Subjected ds/dy from the above equation
%and simplied
bc = @(ya, yb) [ya(1) - 1 +H; yb(1)];%BC specified for S(0) = 1+H and S(y_f)=0) 
ymesh = (0:0.005:yf)
solinit = bvpinit(ymesh, [1 0])
sol = bvp4c(f,bc, solinit)
plot(sol.r, sol.s)