Study On The Simulation Of Marine Refrigerated Container And Its Power Consumption Based On SIMULINK

Marine refrigerated container is an important tool for international refrigerated cargo transportation. Although many researches in domestic and foreign have been done on power consumption of marine refrigerated container,power consumption analysis for the whole voyage was still few. Using simulation model, the power consumption analysis for the whole voyage can help us understand the power consumption situation of the marine refrigerated container in the whole voyage under different ambient temperature and find out reasonable energy saving methods. Reducing the heat leakage of container can decrease the power consumption; using vacuum insulation panel which has lower heat transfer coefficient is a possible method. In this paper, the thermodynamic simulation model of refrigerating unit and the mathematical model of container’walls were built, further more, the system model of marine refrigerated container were built which based on a 20 feet standard marine refrigerated container and then, conducted the simulation calculation with Simulink. The models were verified by experimental data. The power consumption of a marine refrigerated container using polyurethane foam in a real voyage was analyzed by the simulation model, and compared with simulation data from a marine refrigerated container using vacuum insulation panels.Firstly, the thermodynamic models of compressor, condenser and evaporator were built respectively which were parts of marine refrigerated container’s refrigerating unit. The compressor model was used to calculate the mass flow rate of refrigerant, power consumption, discharge temperature and pressure of compressor. Using the measured structure parameters of evaporator and condenser, their steady lumped parameter models were established. The function of expansion valve was realized by keeping the superheat degree constant in the outlet of evaporator. According to the coupling relationship among the components of refrigeration unit, the simulation model of refrigerating unit which consists of evaporator, condenser and compressor was built with Simulink; the model of enclosure structure of the container was built according to conservation of energy. Finally, two models combined to the whole system model for marine refrigerated container.Secondly, using the experimental rig, a series of experiments under different ambient temperature and different setting temperature inside the container were conducted. The heaters which were placed in the container were used to simulate the thermal load. 5k W, 6k W, 7k W, 8k W and 9k W thermal load were added in the container respectively and the operating data of the system was recorded. and the energy efficiency of system in different operation conditions were calculated. Then, the simulation model of marine refrigerated container was verified by comparing the cooling capacity, power consumption of compressor and COP with experimental data under the same operation condition.Finally, by using the simulation model of marine refrigerated container, analyses the power consumption of a conventional marine refrigerated container which sailed from Xiamen to Dalian in September. Putting forward the idea that conventional polyurethane foam was replaced by vacuum insulation panel, then the power consumption of the new container was analyzed with the simulation model in the same voyage. The simulation results showed that when the vacuum insulation panel was adopted, the power consumption of the system reduced 7.5 percent and the energy-saving was realized.