[kalaikdr]

How do I calculate derivative of a fluid property wrt temperature, like d(rho)/dT or d(viscosity)/dT?
I am working on heat transfer in two phase systems where temperature gradients create vast differences in properties.

Are there schemes to calculate these derivatives? I could find only divergence, laplacian and grad schemes. How do i incorporate a new discretization scheme for a derivative like above? I am currently using interFOAM with temeperature incorporated!

Thanks!

[chriss85]

Originally Posted by kalaikdr

How do I calculate derivative of a fluid property wrt temperature, like d(rho)/dT or d(viscosity)/dT?
I am working on heat transfer in two phase systems where temperature gradients create vast differences in properties.

Are there schemes to calculate these derivatives? I could find only divergence, laplacian and grad schemes. How do i incorporate a new discretization scheme for a derivative like above? I am currently using interFOAM with temeperature incorporated!

Thanks!

You might have to extend the thermophysical model that you're using, to provide a function that calculates this derivative. Then you can use it in the equation you are solving. Depending on the model this can be an analytical or numerical derivative.

[kalaikdr]

Thank you Chriss. But I ended up giving a constant value for the derivative. It was a very small magnitude anyway.