Simulation analysis and structural optimization of hot-air bonding oven based on finite element method
Objective The production efficiency of a hot-air bonding could be low and not efficient in energy consumption because of uneven temperature and flow field inside the oven.In order to improve the performance of the oven and reduce energy consumption,this research aims to analyze the flow field and temperature field inside the hot-air bonding oven and optimize its structure to enhance the uniformity of the temperature and flow field inside the oven.Method The internal flow field of the oven was simulated and optimized using the finite element analysis method.A three-dimensional model of the oven fluid domain was established using SolidWorks,and the boundary conditions for simulation calculation were set according to the working conditions of the oven.The flow resistance value of the fiber network was obtained through experimental measurement,and a porous medium model with the same flow resistance was set to replace the actual model of the fiber network,and the Fluent software was used to simulate and calculate the fluid domain model inside the oven.The correctness of the simulation modeling and calculation was verified through experiments.Results The simulation results of the original oven model showed that the internal flow field had a large flow rate in ducts 1 and 3,and a small flow rate in ducts 2 and 4.There were severe vortices in ducts 1 and 3,causing irregular airflow and significant overall flow field non-uniformity.The lowest temperature on the surface of the fiber network was 130 ℃,with the overall uniformity of 86.43％,and a total standard deviation of 6.97.The data indicates that the temperature distribution on the surface of the fiber network was relatively scattered,and the temperature uniformity was poor.It was found from the optimized oven simulation results that the flow rates in each duct were basically the same.After installing a deflector in the upper duct,the deflector guided and directed the airflow,resulting in a stable airflow in the upper duct and the disappearance of vortices.This significantly improved the uniformity of the internal flow field in the oven.The lowest temperature on the surface of the fiber network was 150 ℃,The minimum temperature was increased by 20 ℃.The worst temperature uniformity at characteristic points was 90.1％,the temperature difference in different areas decreases,the overall uniformity was 93.6％,and the overall temperature standard deviation was decreased from 6.97 to 3.72,and the overall uniformity coefficient increased from 86.43％to 93.06％,indicating significant improvement in temperature field uniformity.Conclusion After the optimization of the inlet channel structure and the upper duct,the uniformity of the flow field and flow rate inside the oven has been improved,and the generation of vortices in the upper duct has been reduced,resulting in a more uniform airflow.The standard deviation of the temperature on the fiber surface is decreased,the uniformity coefficient is increased,and the uniformity of the temperature field and flow field has been significantly improved.It is recommended to set the temperature at the oven inlet to around 165 ℃,at which the temperature on the surface of the fiber network inside the oven can meet the requirements for the temperature of the dual-component hot-melt fibers.This not only helps to improve the performance of the oven but also achieves the goal of energy saving and consumption reduction.
finite element analysishot air viscosity ovenporous media modeluniformityinternal flow fieldnon-glue cotton
万方数据
维普
