Optimum Design Methods of Pressure Cooling System for Fruits and Vegetables

点击翻译按钮获取中文摘要

In order to establish the optimum design methods of pressure cooling system for fruits and vegetables, first, cooling time, superficial velocity and energy consumption for some fruits and vegetables were measured by experiment, secondly, heat transfer coefficients for cooling packed beds of fruits and vegetables were calculated by finite element method. Results obtained were as follows:(1) The author defined that the energy required to cool one centigrade per kilogram with opparatus load was a unit cooling energy consumption(U.C.E.C).(2)The cooling of agricultural products by superficial velocity correspond to a minimum U.C.E.C. meant that the ratio of refrigerator energy to total U.C.E.C. had a maximum and it of axial flow fan had a minimum.(3) The superficial velocities at that time were 0.2-0.4m/s for any packed beds of agricultural products, and U.C.E.C. of agricultural products were 1.6-3.3x10 kw. hr/kg C. these values were smaller than that of forced air cooling.(4) The optimum heat transfer coefficient were 20 for packed bed of Unshu Mandarin and 25 kcal/m^2 hr C for taro, respectively.