Flow Mixing in the Gap between the Cars in Tunnel Kilns

摘要

The effect of side injection on mixing of the two axial flows i.e flow through the ware and flow through the gap between ware and walls in the preheating nzone of tunnel kiln is investigated. The 3D temperature field in the cross section between two cars is calculated using the CFD tool (ANSYS Fluent). The mixing quality is evaluated using the contours of temperature, the frequency of temperature distribution and the maximum temperature difference. The influence of injection flow rate, injection velocity, position of nozzels and nozzle number on the mixing behaviour are analyzed. The results show that use of two side injection nozzles is more effective than one side injection nozzle to achieve mixing. Moreover, a relatively better mixing is achieved when the nozzles are installed at the opposite side walls at higher vertical distance (larger distance apart). The mixing quality increases strongly until an impulse flow rate of about 4 N. For higher values of impulse, the influence becomes relatively low.