Investigating direction characteristics of the heat transfer coefficient in forced convection reflow oven

In this paper, we investigate the heating capability of forced convection reflow ovens and the effect of the ovens' construction on it. This parameter depends on the heat transfer coefficient (α) which is mainly determined by the gas flow parameters. First of all we studied the gas flow circumstances in the reflow oven using a stationary and isothermal gas flow model. The conclusions of the model are then proved by experimental results as well. Our experiments were based on measuring the temperature changes on different points which are located around the centre of the ovens' processing area. From these data, direction characteristics of α were calculated using the heat equation of the investigated reflow oven. Our results are important for effective thermal modelling of the reflow soldering process [B. Illés, G. Harsányi, 3D thermal model to investigate component displacement phenomenon during reflow soldering, Microelectronics Reliability 48 (2008) 1062-1068] and are useful to calibrate reflow ovens. In this project we examined the latest reflow ovens constructed with nozzle-matrix blower system.