Numerical Simulation Of Sanitary Ceramics Drying Room And Heat And Mass Transfer Of Green Body Drying Characteristic Analysis

With the adjustment of China’s energy structure and the transformation and upgrading of the ceramic industry,under the increasingly severe energy and environmental problems,how to improve the utilization rate of energy and reduce the emission of pollutants has become the primary problem to be solved in the development of the ceramic industry.In the production process of sanitary ceramics,the energy consumption required for green body drying is relatively large.By analyzing the flow field inside the ceramic drying room and the heat and mass transfer process of green body drying,the structure of the drying room can be optimized and the drying efficiency of the green body can be improved..In this paper,the steady-state simulation of the velocity field and temperature field inside the drying room is carried out,and there are 4different inlet methods for the drying room: the two sides of the single layer are opposite to each other,the two sides of the single layer are staggered,the two sides of the double layer are opposite,and the two sides of the double layer are staggered.Inlet flow velocity:6m/s,7m/s,8m/s,8 different spoiler fan pressures: 0Pa,30 Pa,50Pa,70 Pa,90Pa,110 Pa,130Pa,150 Pa,7 different inlet temperatures: 60℃,65℃,70 ℃,75 ℃,80 ℃,85 ℃,90 ℃ working conditions were studied,and the method to improve the uniformity of the flow field and temperature field inside the drying room was explored;The transient simulation of the quality process was carried out,and the influence of the temperature,humidity and flow rate of the drying medium on the drying effect of the green body was studied.The main conclusions of this study are as follows:（1）The influence of the inlet flow velocity,inlet temperature,inlet mode,and turbulent fan pressure on the velocity field and temperature field inside the drying room is studied by simulation,and four evaluations are adopted: velocity unevenness coefficient,velocity mean value,temperature standard deviation,and dimensionless temperature.The index performs uniformity analysis on the velocity field and the temperature field.The analysis shows that when the inlet mode is staggered on both sides,the inlet flow rate is 6m/s,the inlet temperature is 70℃,and the pressure of the spoiler fan is 110 Pa,the uniformity of the velocity field and temperature field inside the drying room is the best.（2）The transient simulation of the heat and mass transfer process inside the green body was carried out by using the porous medium model,and the effects of the flow rate,temperature and humidity of the drying medium on the drying of the green body were studied respectively.Through simulation analysis,it is concluded that the direction of the humidity gradient inside the green body is from the center of the green body to the surface of the green body,while the temperature gradient is opposite to the humidity gradient;the highest temperature gradient and humidity gradient are at the top corners of the green body,so these parts are also the most It is easy to produce thermal shock,cracks and deformation,affecting the quality of the green body drying.（3）By simulating the heat and mass transfer process of drying a single green body within 2400 s,it is concluded that the heating rate of the green body is increased by11.9% and the drying rate is increased when the drying medium flow rate is 3m/s compared with the working condition of 2m/s.Compared with the working condition of70 ℃,the heating rate of the green body is increased by 8.9%,and the drying rate is increased by 10.44%;the working condition of the drying medium humidity of 30% is the same as the drying condition.Compared with air,the heating rate of the green body is increased by 3.39%,but the drying rate is decreased by 9.24%.It shows that increasing the flow rate and temperature of the drying medium is beneficial to the heating and drying of the green body,and increasing the humidity of the drying medium is beneficial to the heating of the green body,but it is not conducive to the evaporation of water inside the green body.