Numerical Research in Effects of Baffles on Heat Transfer Characteristics of a Tunnel Kiln’s Flue Gas Heat Exchanger

In order to investigate effects of baffles on heat transfer characteristics of a tunnel kiln’s flue gas heat exchanger, the flow fields and temperature fields in two exchangers, one with baffles and the other without, under operative conditions, are separately simulated by using FLUENT code. According to simulation results, average temperature at the air outlet and average pressure at the air inlet of the exchanger with baffles are separately 67.2°C and 265 Pa, and those in the case of the exchanger without baffles are respectively 60.4°C and 240 Pa. Reasons why the baffles exert high influence on heat transfer characteristics of the exchanger are analyzed. On basis of the data and analysis, two conclusions are drawn: (1) Installation of baffles exerts high influence on heat transfer characteristics of the heat exchanger studied. (2) The reason why the baffles could exert such influence is that the baffles prevent much air from flowing into external zones of the baffles, so in per unit time more air exchanges heat energy with hot walls of heat exchange tubes, which are in internal zones of the baffles.