LI Jie, HU Guolin, SUN Jian, ZHU Yonghong

(Jingdezhen Ceramic Institute, Jingdezhen Jiangxi 333001)

Abstract: Firstly, the dimensions and thermal parameters of a ceramic tunnel kiln's flue gas heat exchanger under operative conditions are measured. Secondly, the flow field and temperature field in the operative heat exchanger are numerically simulated by using FLUENT, a CFD soft ware. The average temperature at the flue gas outlet and some other parameters gotten from the simulation fit those from measurement. The velocity vector distribution of the fluid particles and the nephogram of the temperature field in the computational domain accord with the rules of fluid flow and heat transfer. On the basis of the work above, heat transfer characteristics of the heat exchanger are researched and conclusions are drawn: (1) for per unit time, energy decrease of the gas flowing across the exchanger, the energy increase of the air, and the dissipating heat from the outwall of the exchanger into the surroundings are 157.2kW, 150.9kW, and 6.3kW, respectively; (2) the loss of the mechanical energy of the gas flowing across the exchanger is much higher than that of the air flowing across the exchanger; (3) the temperature drop is relatively low and the loss of the mechanical energy is relatively high for the gas from the gas inlet to the outlet, so the heat transfer of the exchanger need be improved.

Key words: ceramic tunnel kiln's flue gas heat exchanger; heat transfer characteristics; numerical simulation for flow field and temperature field; FLUENT soft ware