Heatflux and isothermal boundary condition for incompressible formulation

anant.diwakar · April 11, 2016, 08:18

Hi all,

I want to simulate an incompressible channel flow with heatflux at the wall.

The temperature is always zero for any value of heatflux value in the
MARKER_HEATFLUX.

Is heatflux boundary condition not implemented for incompressible simulation ?

Thanks
Anant

Sprotte · April 12, 2016, 10:43

Hi Anant,

within the incompressible setting, the flow solver does not incorporate the energy equation since temperature wouldn't influence the pressure and momentum variables anyway.

You could use estimates for the heat flux just depending on the flow solution (that is, without knowing the temperature field), e.g. the boundary layer ones that use the shear stress values on the boundary.
As far as I'm concerned, there are a lot of different approaches then. The easiest is the one for laminar flows, where the heat flux is approximately given by the product of shear stress times specific heat.

Regards,
Ole

April 11, 2016, 08:18	Heatflux and isothermal boundary condition for incompressible formulation	#1
anant.diwakar New Member Anant Diwakar Join Date: Sep 2012 Posts: 4 Rep Power: 13	Hi all, I want to simulate an incompressible channel flow with heatflux at the wall. The temperature is always zero for any value of heatflux value in the MARKER_HEATFLUX. Is heatflux boundary condition not implemented for incompressible simulation ? Thanks Anant

April 12, 2016, 10:43		#2
Sprotte Member Ole Burghardt Join Date: Mar 2016 Location: Kiel, Germany Posts: 60 Rep Power: 10	Hi Anant, within the incompressible setting, the flow solver does not incorporate the energy equation since temperature wouldn't influence the pressure and momentum variables anyway. You could use estimates for the heat flux just depending on the flow solution (that is, without knowing the temperature field), e.g. the boundary layer ones that use the shear stress values on the boundary. As far as I'm concerned, there are a lot of different approaches then. The easiest is the one for laminar flows, where the heat flux is approximately given by the product of shear stress times specific heat. Regards, Ole