My Math Forum Best approach for solving four ODE's

 Differential Equations Ordinary and Partial Differential Equations Math Forum

 June 15th, 2015, 07:48 AM #1 Newbie   Joined: Jun 2015 From: Scotland Posts: 2 Thanks: 0 Best approach for solving four ODE's Hi, I have a problem where I have four non-linear differential equations. They are big and ugly, but I think they can be summarised as follows: dA/dz = f(A,B,C,D) dB/dz = f(A,B,C,D) dC/dz = f(A,B,C,D) dD/dz = f(A,B,C,D) I would like to integrate these equations over the range of z=0 to z=L, in order to obtain profiles of A, B, C and D. I have tried to use matlab for this, but am not very comfortable with this program, and so was considering using excel. Firstly, I would like to know the terminology for such a system of equations, in order to make it easier to find relevant information on the internet. Any help would be required (I only have excel and matlab for this). Thank you
 June 15th, 2015, 07:54 AM #2 Global Moderator   Joined: Dec 2006 Posts: 20,919 Thanks: 2202 Would the function denoted by f be different for each equation?
 June 15th, 2015, 09:10 PM #3 Newbie   Joined: Jun 2015 From: Scotland Posts: 2 Thanks: 0 Yes, sorry. The four functions are different.
 June 16th, 2015, 02:03 AM #4 Senior Member   Joined: Apr 2014 From: Glasgow Posts: 2,157 Thanks: 731 Math Focus: Physics, mathematical modelling, numerical and computational solutions If you provide the equations in more detail, we'll try and see if we can employ tricks to find an analytical solution. You might have to consider a numerical solution...

 Tags approach, ode, solving