solve equation sets
 

consider following equation sets whats ur suggestion for solving it openFOAM

1) dT/dt =A1 dX/dt +B1 dY/dt
2) dX/dt =A2 exp(B2/T) (1-X)(C2-D2Y-X)
3) dY/dt = A3 exp(B3/T) (1-Y)(C3-D3X-Y)

A,B,C,D are constant

thank you

I would consider using the ODE solvers in either octave or matlab.

I agree with Ben - Octave and MATLAB are more suitable. But, if you must use OpenFOAM for some reason, I'd use the sixDOFsolver as a template.