NUMERICAL INVESTIGATION OF THE FLOW FIELDS AND THERMAL PATTERNS IN A LARGE COLD STORE (Ⅰ)

摘要

Refrigeration for the cold storage of perishable foods has been utilized for more than a century. The need for refrigerated storage grows with hot weather. The frozen food industry expanded many times in freezer storage in a few decades after World War Ⅱ. Cold storage facilities are also significant energy consumers that call for attention to thermal behavior as it greatly influences the cost. Proper design to improve thermal behavior of a refrigerated space requires the knowledge of air distribution and thermal conditions within the space. The frozen food quality is sensitive to both storage temperature and fluctuation in temperature. The present work made use of a computational fluid dynamics technique to adequately predict the cold storage airflow pattern variations within the cold room under various evaporator's arrangements of sizes, numbers and positions. Design parameters included local temperatures and velocity distributions inside a large cold store using standard k-e model with mesh element 5,400,000 tetrahedral cells. Different optional designs utilizing different number of evaporators were investigated as well as the locations of these evaporators according to load estimation of the cold store.