Re: activity boundary condition
Posted: Wed Feb 18, 2015 9:29 am
Hi, Bernd,
I think if there exists an oxygen activity gradient across the oxide, then the A and B must move, because the system satisfies the thermodynamic relationship Gibbs-Duhem Equation: In which, you have chosen one matrix component and used the diffusion potential to replace Chemical potential in the equation of diffusion flux, so that make it independent, right?
So A and B should move, do you think so ?
However, I have questions about how MICRESS will calculate the initial quasi-equilibrium at the interface? As I have tried, the initial composition of different phase is totally wrong output on the screen, for example, there should be no A and B existing in the gas phase, but the initial composition for quasi-equilibrium calculation output on the screen include A and B (which is the same problem as average composition) , so do you have some good solution to this problem ??
regards,
tatalemon
I think if there exists an oxygen activity gradient across the oxide, then the A and B must move, because the system satisfies the thermodynamic relationship Gibbs-Duhem Equation: In which, you have chosen one matrix component and used the diffusion potential to replace Chemical potential in the equation of diffusion flux, so that make it independent, right?
So A and B should move, do you think so ?
However, I have questions about how MICRESS will calculate the initial quasi-equilibrium at the interface? As I have tried, the initial composition of different phase is totally wrong output on the screen, for example, there should be no A and B existing in the gas phase, but the initial composition for quasi-equilibrium calculation output on the screen include A and B (which is the same problem as average composition) , so do you have some good solution to this problem ??
regards,
tatalemon