[eng_yasser_2020]

Hi,

I have a model consists of two concentric pipes and a gas in between. The ambient air surrounding the outer pipe. The inner and outer pipes made of aluminum and have heat sources (W/m3). The analysis will be 2D Planar, Steady state and check the gravity. I have used the Boussinesq Model for the gas and the ambient air. The questions are:

1- What is the constant value of density or how it will calculated ? (The density in my case is a function of pressure)

2- How can we get the Thermal Expansion Coeff. of the gas and the air??

3- How can we solve this problem if the pressure of the gas changed??

Thanks