Recent content by ktsharp

[UPDATED] I have the following system of partial differential algebraic equations: \frac{1}{H}\frac{\partial H}{\partial t} = - \frac{\partial W}{\partial x} - \frac{f_1(H,c,W)}{H}, \frac{1}{H}\frac{\partial}{\partial t}(H c) = - \frac{\partial}{\partial x}(W c) - \frac{f_2(H,W,c)}{H}...

I have the following system of partial differential algebraic equations: [ tex ] \frac{1}{H_p}\frac{\partial H_p}{\partial t} = - \frac{\partial W_p}{\partial x} - \frac{f1(H_p,c_p,W_p)}{H_p}, [ \tex ] [tex] \frac{1}{H_p}\frac{\partial}{\partial t}(H_p c_p} = - \frac{\partial}{\partial...

Hi Everyone, I am trying to solve a system of non-linear differential equations coupled to algebraic expressions: W(x)' = f(Cn(x)), where n = 1:6 C1(x)' = f(Cn(x),V1(x),V2(x)) C2(x)' = f(Cn(x),V1(x),V2(x)), C3(x)' = f(Cn(x),V1(x),V2(x)), V1(x)'' = f(Cn(x),V1(x),V2(x)), 0 =...

I've realized that I haven't declared any parameters, and thus introduce an extra dimension. This was the problem!

I have an overdetermined nonlinear system of ODEs: W' = f(c) c'' = f(W,W',c) and boundary conditions W(0)=a,W(L)=-a c(0)=c(L)-b I can split up the equations into three first order ODEs, and solve numerically with Matlab. I would like to use bvp4c, but I believe I have too many...

Thanks again for your help. So what happens with the nonlinear terms in the second equation?

Thank you for your reply! I am not familiar with the FEM, although I am familiar with finite difference methods, which is what this seems to be as you have written it above, but for an ODE. If I make the above assumption, I will get y_{i+1} = y_{i}(hb+1) + ha...

I'm intending to solve the following BVODE: \frac{dy}{dx} & = & a + by, \frac{d^{2}z}{dx^{2}} & = & {\alpha}y\frac{dz}{dx} - \beta +cz\frac{dy}{dx}. I have the boundary values for both y and z at x=0, L, however I do NOT have any values for either first derivatives...