Hello, Does anyone know how
 

Hello,

Does anyone know how the thermal diffusivity for enthalpy is derived ?

Both
"src/thermophysicalProperties/specie/transport/sutherland/sutherlandTransportI.H " and
"src/thermophysicalProperties/specie/transport/const/constTransportI.H"
in the function alpha() calculate this as:

alpha = kappa / CpBar

with

CpBar = ( (T - Tstd)*(H(T) - H(Tstd)) + Cp(T) )/(sqr(T-Tstd) + 1 )

I would have thought it would be
alpha = kappa/Cp(T).

thanks
Dave

Re: thermal diffusivity for enthalpy - what is it and what is Cp bar ????
 

I was wondering about this also.

For T = Tstd, Cp bar is undefined, therefore I can't understand what sort of property Cp bar is. Some texts call Cp bar the mean value of Cp but that really doesn't make sense here either.

Anyone ???

Richard