Simulation Research Of The Marine Refrigeration And Air Condition System

Marine refrigeration system and air condition system are very important auxiliary equipments on the ship, which could effectively improve people’s living environment, working condition, as well as health situation. In recent years, there is not so much research for the simulation of refrigeration and air condition that aims at the marine field. Therefore, it is essential to research on the modular modeling and simulation of the marine refrigeration and air condition system.The refrigeration and air condition system of an advanced million TEU container ship is adapted as the mainly simulation object in this paper. Firstly, the work process and dynamic characteristics of refrigeration and air condition system are analyzed, and the composition of the system is introduced. Secondly, using the method of modular modeling, through the application of thermodynamics, heat transfer theory knowledge, the dynamic mathematical model of marine refrigeration and air condition system is established under the base of simplification and necessary assumptions. The main math model that established in the paper is the four basic components in the system: compressor, condenser, evaporator and expansion valve. The PID control algorithm and fuzzy control algorithm are designed in the paper for the main control component in the system--electronic expansion value. Meanwhile, two-position control algorithm is designed for the compartment temperature.Based on the established mathematical model, the simulation system of refrigeration and the air condition is designed and developed through the software VC++6.0respectively, and has been put into the use of the related marine engine room simulator. The running status of the components such as compressor, evaporator and condenser can be real-time showed. The system controlled parameter can be regulated real-time to simulate the actual work process. The system has the function of achieving control operations and setting system fault to simulate the actual operating conditions on the ship. The simulation result shows that system can reflect the real working condition and the actual dynamic process of refrigeration and air condition system completely and realistically, meet the requirements of visualization simulation training.