[zhaohb11_cfd]

Dear OpenFoam Uers，

Recently, I use interFoam to simulate the droplet impacting on rigid surface. I did the energy analysis study and find that the energy is not conservative.

The total energy, surface energy, kinetic energy and viscosity dissipation against time is plotted in the attachment. It could be observed that the viscosity dissipation kept increasing. even when the kinetic energy is limited to zero.

I used the following to calculate the viscosity dissipation:

First, I calculate the viscosity dissipation rate:

phi= 2*dynamic viscosity coefficient *(b&&b) and b=0.5*（grad(U)+grad(U).T()）

After getting the viscosity dissipation rate, I integrated it over the time step and grid space:

viscosity dissipation energy = phi*vol()*0.00025*alphawater;

Anyone knows that if it is the right way to calculate the viscosity dissipation energy? Or explain why the energy is not conservatitve?

sincerely
ZHAO HAIBO

[zhaohb11_cfd]

anyone could help me ?

[ahparvin]

Hey did you manage to find it?

I have a similar issue. the energy conservation is really questionable for me?
I want to know to what extent I can trust OpenFOAM in terms of this matter.
what is the role of numerical dissipation and turbulence, etc?