Numerical analysis of a radiant drying oven for web applications

During the manufacture of prepregs (composite material made of resin with fiber reinforcement), for the electronics industry, solvent evaporation and product heating are important aspects of the production process. A mathematical model is presented to describe convective and infra-red radiant heating and solvent evaporation from a web (product being processed before being finished as prepreg) in a solvent removal oven. Differential equations are used to model the mass and energy transfers occurring within the oven. Radiation enclosure theory is employed to describe the infrared heat transfer within the oven and use is made of a solvent evaporation model from the literature. Results of temperature distributions in the heated plate (oven component), the web and the air/solvent mixture; the convective and radiant heat transfer rates to the web, the web solvent concentration and the effects of varying the web velocity, heater temperature, heater size and inlet air temperature are in agreement with theory. The results yielded good agreement with a similar study in the literature. Careful analysis of the results of computer simulations under different conditions, such as presented in this study, can be expected to lead to better design decisions prior to building an infra-red oven for web applications.