Numerical Analysis And Optimization Of Drying Room For Automobile Body Coating Line Based On CFD Technology

With the rapid development of the new paint coating production line and the new equipment,the quality and power consumption of the drying room in the area of coating applications hasbecome an demand. In this paper, for the problem of higher energy, the uneven wind speed andtemperature in work area of the drying room of Dongfeng Nissan Diesel Automobile BodyCoating Line, the simulation model of the body drying room is built by the computational fluiddynamics (CFD) software of Fluent. The hot air circulation drying characteristics of the bodydrying room is analyzed, and a new design method of air channel model of variable cross-sectionis proposed. Then a semi-circular channel model of variable cross-section structure is designed,and process parameters are optimized for saving the energy. The main research contents asfollows:1. The hot air circulation drying characteristics of the body drying room is studied. Toensure the normal process of coating film, the influenced factor of the energy consumption andthe internal temperature and velocity distribution is analyzed by analyzing the different dryinginfluencing factors (such as temperature, humidity, speed and initial temperature of theenvironment) and different way of hot air circulation.2. To the drying room of Dongfeng Nissan Diesel Automobile Body Coating Line, the threedimensionalphysical model is established. Then the regulation for change of temperature withtime and wind speed under the state of thermal retardation is obtained inside the drying room bynumerical simulation analysis. Besides, the accuracy of numerical simulation for the body dryingroom is verified by experiment.3. A new design method of air channel model of variable cross-section is proposed. Severalstructures of variable cross-section for body drying room are established, which improved theuniformity of the inlet wind speed effectively, and enhanced the temperature uniformity of workarea. Meanwhile, uniformity coefficient of wind speed as evaluation index, a semi-circularchannel model of variable cross-section is designed through calculation, analysis and comparison. 4. The thermo dynamic model of the body drying room is established by application of theoptimized structure of semi-circular channel model of variable cross-section. Temperatureheating costs is selected as optimization objective, temperature, speed, humidity, and initialtemperature as optimization process parameters. Orthogonal test is used to arrange experimentschemes, the optimization scheme is obtained by the result analysis. Compared with primarybody drying room, the temperature heating costs of optimization body drying room has beenreduced 5%, and the purpose of optimization is achieved.5. Finally, the full text is summed up, and the further study prospect is proposed.