CAJ | 학술논문

精确掌握温度控制是实现高质量食品冷链运输的关键，节能减排降低运输成本也是供应商所追求的目标。该文以短距离冷藏运输车为研究对象，以土豆为货物区试验材料，建立了求解冷藏车车厢温度场分布计算模型。模拟过程采用2种不同的风机制冷温度（0和3℃），依据制冷机组功率和货物最佳冷藏温度，确定运输过程中打开和关闭制冷风机最佳间隔时间。模型以冷气出风口风速、冷气温度、车厢以及货物的初始温度、货物的物性参数为边界条件，采用计算流体力学（CFD）非稳态SSTκ-ω计算模型，模拟开启风机和关闭风机不同阶段车厢内温度场的分布情况。结果表明在组合方式为制冷温度3℃，制冷时间和关闭制冷风机阶段都为10 min时比制冷温度为0，制冷时间15 min和关闭制冷风机为20 min时要节约3.6×105 J能耗。该研究为合理选择制冷风机温度和冷却时间最佳组合方式，以及实现节能减排降低运输成本提供了依据。
정학장악온도공제시실현고질량식품랭련운수적관건，절능감배강저운수성본야시공응상소추구적목표。해문이단거리랭장운수차위연구대상，이토두위화물구시험재료，건립료구해랭장차차상온도장분포계산모형。모의과정채용2충불동적풍궤제랭온도（0화3℃），의거제랭궤조공솔화화물최가랭장온도，학정운수과정중타개화관폐제랭풍궤최가간격시간。모형이랭기출풍구풍속、랭기온도、차상이급화물적초시온도、화물적물성삼수위변계조건，채용계산류체역학（CFD）비은태SSTκ-ω계산모형，모의개계풍궤화관폐풍궤불동계단차상내온도장적분포정황。결과표명재조합방식위제랭온도3℃，제랭시간화관폐제랭풍궤계단도위10 min시비제랭온도위0，제랭시간15 min화관폐제랭풍궤위20 min시요절약3.6×105 J능모。해연구위합리선택제랭풍궤온도화냉각시간최가조합방식，이급실현절능감배강저운수성본제공료의거。
Accurate temperature control is the key to achieving high quality food in cold-chain transport, and the suppliers pursue the goal of energy efficiency, emissions reduction, and transportation cost reduction. This paper takes the short distance refrigerated truck as the research object and potatoes as the experimental goods, and then establishes the calculation model for solving the temperature distribution in the refrigerated compartment. Two kinds of fan cooling temperatures (0 and 3℃) and cargo areas under the“blanks on both two sides and middle”stack method were used to simulate the cooling process. According to the refrigerating unit power and best refrigerating temperature of goods, the optimal time interval was defined to open and close a cooling fan in the process of transportation. Taking the wind speed at the air conditioning outlet, air-conditioner temperature, refrigerated compartment, initial temperature of the cargo area, and the physical parameters of goods as the initial boundary conditions, a 3D numerical calculated model of the car body was built by using a porous model, which took the average values of the three directions (0, 90°, 135°) of wind speed as the actual wind velocity in a physical simulation. The unsteady numerical simulation methods of Computational Fluid Dynamics (CFD) were used to model the distribution of the temperature field in a refrigerated compartment with different stages of an opening and closing fan. The results showed that, based on the contour map of temperature field in different section of Z-axis direction, the increased rate of the cargo area temperature reduced gradually. It was suggested to add a piece of iron plate on the upper surface of the cooling fan motors, to enhance the flow strength of the front cold air and improve overall cooling rate in the goods. The change of average temperature and temperature distribution of the goods area were compared with the cooling stage and the natural convection stage. The data indicated that when the refrigeration temperature was 3℃and cooling plus closing time of cooling fan were both 10 minutes, the energy of 3.6×105 J was reduced compared with the refrigeration temperature was 0℃, cooling time was 15 min and the closing fan lasted 20 minutes. The combination was more advantageous to reduce nonessential energy consumption and improve overall transport economic benefit. The model was validated by comparing the simulation values with measured values, and the results showed that the root mean square error was 0.540℃ and the mean absolute error was 0.493℃, which showed the rationality of the design scheme and the accuracy of the selected calculation model. The study revealed the temperature distribution of goods under various cooling temperatures and cooling times in the whole process of transportation. It also provided a reliable theoretical basis for reasonable selection of the optimal combination mode of cooling fan temperature and cooling time, reducing transportation costs, and realizing energy conservation and emissions reduction.