INFILTRATION LOAD IN COLD ROOMS

A two dimensional model was developed to predict the infiltration load to a cold room through ifs doorway. The governing equations were deri ved and transformed into dimensionless form. The model showed that the infiltration load to a cold room depends on three dimensionless param eters: the Grashof number of the cold room, the aspect ratio of the ro om (height to width), and the opening ratio (height of doorway to heig ht of the room). A finite difference technique with a control volume a pproach was used to solve the governing equations. Staggered grids wer e used, extending them beyond the doorway to account for the air motio n outside the cold room. A SIMPLER algorithm, with finite difference f ormulation was used to solve the governing equations together with the ir boundary conditions. The model was used to predict the flow pattern and the temperature distribution in the cold room due to the infiltra tion through the doorway. The results were also utilized to study the variation of the rate of infiltration and the doorway flow factor with the rime measured from the moment the door was opened. The results ar e presented for the Grashof number from 10(5) to 10(7) and 10(10), and opening ratios of 0.5 to 0.25. Comparisons of results with those in t he 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.