Numerical Simulation Research On PCB Film Drying Box Air Inlet Optimization

Drying is one of the key factors relating to the film production process,and is the most important link affecting the quality of film.People do a lot of research about the process of drying box structure and process,but there is still lack of theoretical guidance of design of the air film and without detailed experimental research about the drying characteristics.In order to improve drying quality and drying efficiency of PCB film,this paper takes the drying box of a film factory in Shantou as the research object. Analyses the common heat transfer characteristics of three types of nozzle structure, choose the optimal structure of nozzle,controlling the nozzle spacing optimization of the air distribution of drying oven.Using Gambit to establish a drying box, Fluent calculation, finally using Tecplot to analyze the calculation results.The main research work and achievements of this article are:(1) Analysis of three kinds of common slit nozzle(“one”?“T”?“V”).Through the simulation,we got the heat transfer characteristics near the surface of the film.The results showed that,no matter the nozzle is out or not, it has no influence on the uniformity of the temperature field distribution near the surface of the film?(2) Despite the nozzle is out or not,its impact on temperature distribution on the surface of the film is not big, but it had a greater influence on the heat transfer coefficient on the surface of film, compared to the operation condition of the nozzle zero out, because the nozzle out of a certain length has certain guiding function to the hot air, fluid flow turbulence intensity along the surface flow gradually increases, and thus lead to flow to the turbulent flowing field from the layer, so as to make the film near the surface of the heat transfer coefficient increases,which is beneficial to strengthen the heat transfer, at the same time, the heat transfer coefficient of stagnation zone near the corresponding increases, which greatlyimproves the heat transfer effect of the surface of the film.(3) To obtain the most uniform distribution of the flow field, We control ten different situation and analyzed,From the results of the simulation,we can see that the space of the nozzle should be controlled in the range of 100 mm to 120 mm.