LIU  Zhenqun  HUANG Binjun  YIN Honu

( South一Chin& Institute of Tchnology )

Abstract: In a firing zone of a tunnel kiln, the gas flow and the heat trensler ape more complex than that in any other zones. This paper points out, the major factors affecting the convective heat transfer in the firing zone area . the jet一f1ow from burnners on both sides of the zone and the main-flow formed by the jet-flow. According to the theory of similarity , using aerodynamic mode1, this paper has studied the convective heat transfer in the firing zone by means of counter- therma1- f1ow local simulation. the following conclusions are obtained; 1. When the burnners are arranged opposite , the convective heat transfer equation in the firing zone of a tunnel kiln is; Nu= 4.1 6 0Re°。210 Reo°.14. In the firing zone the convective heat transfer is more influenced by the jet- flow than the main- flow. 2. 1n general situation, the average convective hent transfer can be raised when the burnners are arranged staggeringly in a tunnel kila. This is more effective when tho high-velocity burnners are used. Considering the existing tunnol kilns ，the high- velocity burnners are more suitable to be arranged staggeringly thnn opposito.

Keywords: firing zone;counter- therma1- f1ow; tunnol kilns