Infiltration load in cold rooms.

A two dimensional model was developed to predict the infiltration load to a cold room through its doorway. The governing equations were derived and transformed into dimensionless form. The model showed that the infiltration load to a cold room depends on three dimensionless parameters: the Grashof number of the cold room, the aspect ratio of the room (height to width), and the opening ratio (height of doorway to height of the room). 1\ finite difference technique with a control volume approach was used to solve the governing equations. Staggered grids were used, extending them beyond the doorway to account for the air motion outside the cold room. A SIMPLER algorithm with finite difference formulation was used to solve the governing equations together with their boundary conditions. The model was used to predict the flow pattern and the temperature distribution in the cold room due to the infiltration through the doorway. The results were also utilized to study the variation of the rate of infiltration and the doorway flow factor with the time measured from the moment the door was opened. The results are presented for the Grashof number from Jo-5 to 107 and 1010, and opening ratios of 0.5 to 0.25. Comparisons of results with those in the literature are presented. The good agreement of the simulation with the experiments suggests that the present model is valid for the type of flows compared.