Numerical Simulation and Experimental Study of Thermal Distribution Behavior in Downdraft Ceramic Kiln

Abstract

This research aims to study and analyze thermal distribution behavior in 3.6 m3 downdraft kiln containing standard 10 layers and 250 kg ceramic shelf. This understanding is expected to solve the waste product problem of stoneware ceramic affected by uneven inside temperature. Thermal distribution was analyzed by thermocouple measuring simultaneously CFD method. Regularly, R - type thermocouples measurements were permanently installed for 8 points around the kiln, front middle and rear top, door, mid - rear wall, side wall, chimney and burner. These measuring results compared to CFD show the trend. The temperature on the top kiln was higher than that bottom. The average temperature on the top kiln was around 1,160°C whereas that on the bottom kiln was around 850°C. The CFD results were error from thermocouple measuring for -2 to 5%. However, CFD results also show thermal distribution behavior at the immeasurable point from thermocouple. The temperature distribution on the bottom kiln was uneven. The temperature nearby the front kiln was slightly lower than that rear kiln because the outlet vent to the chimney is near rear kiln.