ham_nola
posted this
01 April 2020

- Last edited 01 April 2020
Hi Karthik & Amine

Thank you for your responses!

**Initial condition**

The domain is initialized with standard initialization from the inlet. The domain is initially filled with saturated water liquid and a velocity of 0.29 m/s (calculated from the mass flow rate of 3 kg/s at the inlet). The vapor volume fraction initially is zero.

I define the inlet static gage pressure as 0 Pascal (I tried running cases with 15 Pa as well).

The operating pressure is1.08e+7 Pa.

**Solution**

Fortunately, I got the result of the volume fraction of vapor I was trying to do. Below is the vapor volume fraction contours in the domain.

My problem was I didn't consider that the density of water vapor at 1.08e7 Pa should be 61.223 kg/m^3. Also, I had to correct the enthalpy and give is values as explained above.

The vapor mass flow rate at the outlet is 0.0701 kg/s which is less but comparable to 0.072 kg/s calculated by hand-calculations!

**ISSUES**

(1). The issue I have is regarding the pressure inside the domain. It is negative pressure at the inlet!

My question would be that does that make physical sense? Here are the contours.

(2). Also, why is the static temperature of the liquid and vapor much much higher than the wall adjacent temperature? Please see contours below

Thank you.

Best regards,

Hamed.