输送带非等温硫化过程数值模拟与实验研究

为了探究输送带在硫化过程中内部不同区域的温度和硫化程度(橡胶交联程度)随时间的变化规律，通过实验得到了橡胶导热系数和比热容在不同温度下的数值，并编写成UDF程序导入FLUENT。通过三种温度145℃、150℃、155℃下橡胶硫化曲线对常用的硫化动力学模型进行拟合分析，确定最佳硫化动力学模型。以C语言和FLUENT预定义宏为基础，编制了UDF用户自定义程序模型，通过有限元分析软件FLUENT实现了输送带硫化过程中传热与硫化度的耦合，最后通过测温实验验证了模拟的精确性。结果表明：选取的硫化动力学模型，初始条件和边界条件的设置，硫化与传热耦合计算方法可以准确预测输送带的硫化过程。输送带外部与内部区域升温速率差异显著，其中心区域是升温速率最慢、焦烧时间最长、最后完成硫化的区域。根据模拟结果可对输送带硫化时间、胶料配方、橡胶预热等方面进行硫化工艺优化。

Numerical simulation and experimental study of non-isothermal vulcanization process of conveyor belt

In order to explore the temperature and degree of vulcanization(rubber crosslinking degree)of different areas of the conveyor belt in the vulcanization process with time,this paper obtains the values of rubber thermal conductivity and specific heat capacity at different temperatures through experiments,and writes UDF program for introduction into FLUENT.The rubber vulcanization curves at three temperatures of 145℃,150℃and 155℃ are fitted and analyzed to determine the optimal vulcanization kinetic model.Based on C language and FLUENT predefined macros,the UDF user-defined program model is compiled,and the heat transfer and vulcanization degree of the conveyor belt are coupled through the finite element analysis software FLUENT,and finally the accuracy of the simulation is verified by temperature measurement experiments.The results show that the vulcanization kinetic model,the setting of initial conditions and boundary conditions,and the coupling calculation method of vulcanization and heat transfer selected in this paper can accurately predict the vulcanization process of the conveyor belt.The heating rate of the outer and inner areas of the conveyor belt is significantly different,and the central area is the area with the slowest heating rate,the longest scorching time,and the final completion of vulcanization.According to the simulation results,the vulcanization process can be optimized for the belt vulcanization time,rubber material formulation, rubber preheating,etc.