Numerical code for computation of aspiration flows in industrial buildings

The design of numerical code for gas-dynamics simulation of aspiration flows was presented. The choice of method for integration of gas-dynamics equations was made. Several possibilities for boundary conditions of hydrostatic case was described.
For simulation of aspiration flows two-dimensional approach was used. In this case, computational domain is rectangle, that corresponding to vertical slice of industrial building. Left, right and bottom boundaries are solid borders. For them we used reflected boundary conditions. On the top boundary gas free flow is available.
There are several possibilities of boundary conditions on the top boundary:

• free flow:
  (a) obvious free flow;
  (b) free only outflow from computational domain (but not inflow into);
  
• hydrostatic equilibrium:
  (a) free flow;
  (b) free only outflow from computational domain (but not inflow into).
  

We perform numerical simulations for all listed variants. The results showed that minimal change of initial hydrostatic balance was given by isothermal hydrostatic boundary conditions. And difference between two their variants is very small.
The two-dimensional numerical code on the base of MUSCL approach and isothermal hydrostatic balance satisfying boundary conditions was developed by us. It is possible to support hydrostatic equilibrium in computational domain with very high accuracy. We think, that this code may be used for tasks of projecting and optimisation of ventilation systems of industrial building with success.
Evolution of this code may be in two directions: the full three-dimensional code and isothermal hydrostatic balance boundary conditions of two order accuracy.