The mixing of the two axial flows through the ware and through the gap between ware
and walls using side nozzles in the preheating zone of tunnel kiln is investigated. The
three-dimensional temperature field in the cross section between the two cars is calculated
using the computational fluid dynamics (CFD) tool FLUENT. The mixing quality is
evaluated using contours, the frequency of temperature distribution, and the maximum
temperature difference. The influence on the mixing behavior of injection flow rate, injection
velocity, nozzles position, and nozzle number has been analyzed. The results show
that using two nozzles is more effective than one nozzle if the nozzles are installed at the
opposite side walls with high vertical distance. The mixing quality increases strongly
until an impulse flow rate (IFR) of about 4 N. For higher values, the influence becomes
relatively low. The results for the mixing temperature obtained through CFD simulation
compared with analytical results show a good agreement with maximum error of 0.5%.