how to couple two different physics?

Hi
Dear friend

I am using Physics "Transient heat diffusion equation in solid" to calculate T(x,y,z,t).
Now another Physics "Distributed ODEs and DAEs(dode)" is used to write the following equation:

dX/dt=(A)*[exp{-E/RT}]

where
A, E & R=constant
T(x,y,z,t)=variable [obtained after solving Physics "Transient heat diffusion equation in solid"]
t= time
x,y,z= space coordinate

want to solve to find out X(x,y,z,t).............
I got a problem here, as i have mentioned, equation contains three variable:

The temperature T is obtained after solving a "Transient heat diffusion equation in solid Physics" and is used as the input to the ODE. That means the two physics "Transient heat diffusion equation in solid Physics" AND "Distributed ODEs and DAEs(dode) Physics" should be coupled together since I need the value of T(x,y,z,t) to calculate X (x, y,z,t).


Can anyone please tell me, how to couple these two physics in COMSOL 4.2??


regards


Anup