【作者】 刘永胜；

【导师】 王晓刚；

【作者基本信息】 西安科技学院 ， 矿物加工工程， 2002， 硕士

【摘要】 多热源合成碳化硅炉炉内温度分布、热量传递及温度梯度变化对碳化硅产品的产量、质量和能耗都有重要的影响。因此，研究合成炉内温度场规律和工艺条件对合成炉温度场的影响，采取一定措施改善生成碳化硅的温度区域，对于从根本上提高碳化硅的产量和质量，降低产品能耗和安全生产具有重要的意义。 对传统的单热源合成炉(Acheson炉)和课题组研究发明的多热源合成炉的温度场进行了传热分析，进行了简化、假设和约定，确定了初始条件和边界条件，建立了数学模型。采用有限元法建立了单热源合成炉和多热源合成炉温度场的有限元几何模型和数值计算模型。分析了所建立的数学模型与ANSYS软件数学基础的一致性，表明采用ANSYS软件对多热源合成炉温度场进行数值模拟研究是可行的。 通过查表及相关运算，确定了采用ANSYS软件所需的热性能参数。通过模拟及实验研究了单热源合成炉温度场随时间和功率的变化规律。分析了不同炉型多热源炉温度场的温度分布、热流量及温度梯度的模拟结果的差异，表明多热源合成炉炉芯之间的热屏蔽作用、温度场叠加作用及相互之间的保温作用是其具有节能、提质和高产等优点的内在原因，并通过实验进行了验证；模拟探讨了不同供电功率时，多热源合成炉内温度分布、热量传递和温度梯度的变化状况，表明供电功率对合成炉的温度分布、热量传递和温度梯度变化具有重要的影响，确定了模拟炉型的最佳供电功率，多热源合成工艺实验表明实验结果和模拟结果基本相符；研究了立体四热源炉内温度场随时间的变化趋势，表明供电时间对炉内温度分布状况和碳化硅反应区域的大小有影响。 研究了热源数目趋于无穷时的合成炉温度分布、热流量和温度梯度的演变规律。表明随热源数目的增多，热源之间的温度场叠加区域的温度分布趋于一致，热流量和温度梯度很小且趋于一致。热源数目为无数多个时，炉芯之间的温度大小一致，炉芯之间温度场成为一个均匀的温度场。利用无数多个热源温度场的启示，提出将导电体掺入反应料使之导电发热合成碳化硅材料的方法，即无芯炉法。 对提出的无芯炉合成碳化硅材料的方法的进行了实验验证研究。研究了反应料配比、供电功率和供电时间等供电制度对碳化硅合成的影响；采用XRD和SEM等 分析测试手段分析了合成的不同类型碳化硅产品的微观形态和特性，并指出了其可－－＿能的应用领域。更多还原

【Abstract】 The temperature distribution, heat-transfer and temperature gradient change have vital influence on yield, quality and energy-cost of SiC product in multi-heat sources synthesis SiC furnaces. Therefore the study on regulation of temperature field and effect of the process condition on temperature field and measure that improving temperature area of silicon carbide synthesis has a great importance to enhance yield and improve quality, decrease energy-cost and safely produce.The temperature fields of traditional single-heat source furnace (Acheson furnace) and multi-heat sources synthesis furnaces invented by our group are analyzed by heat transfer method. The initial and boundary conditions are confirmed, through simplification, hypothesis and assumption of single-heat source and multi-heat sources furnace. And the mathematics models of temperature field are formed in single-heat source and multi-heat sources synthesis furnaces. The geometry models and numerical calculation models of temperature field in single-heat and multi-heat sources furnaces are established through finite element method. The consistency between confirmed mathematics models and mathematics base of ANSYS software is analyzed. It is showed that the study on numerical simulation of temperature field in multi-heat source is feasible with ANSYS software.The heat-performance parameters are determined through table and interrelated operation. The change rules of temperature field and reaction area with time and power are studied in single-heat source by simulation and experiment.The difference of simulation results of temperature distribution, heat flux and temperature gradient in various type furnaces is discussed. It is showed that the inner reasons for energy saving, quality improving, high-yield in multi-heat source furnace arethe functions of heat shield among cores, superposition and heat preservation of temperature fields each other. The simulation results are tested with multi-heat sources technical experiments.The changing rules of temperature distribution, heat-transfer and temperature gradient are simulated also in multi-heat sources furnace when the power is various. The study results show that the power has important effect on temperature field, heat-transfer and temperature gradient. And the optimum power of simulating furnace is ascertained. The experiment results are in accord with simulation results.Subsequently, the changing tends of temperature field are analyzed at different time in multi-heat sources furnace temperature. The study shows that the time has influence on temperature distribution and area of synthesis silicon carbide.And then the evolvement regulations of temperature distribution, heat flux and temperature gradient in furnaces are researched when the heat source number increases infinitely. The result demonstrates that the area temperature, heat flux and temperature gradient among heat sources become uniform and consistent with heat source number increasing. When the heat sources are unnumbered, the temperature among heat sources become coincident and the heat flux value and gradient value are almost naught. The temperature field among heat sources is even and consistent. Based on the study the new synthesized method of silicon carbide is put forward, named non-core furnace method that conductor is added to raw material to synthesis SiC.Finally, the feasibility of non-core furnace method for synthesis silicon carbide is tested by experiment in paper. The influences of raw material batch, power and time on silicon carbide are studied. The microcosmic form and performance of silicon carbide are analyzed through XRD and SEM analysis instrument. The potential application range is pointed out.更多还原