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用内部分析法来分析现存熔铝炉的生产工况即使是可能的,那也是极其困难的.在内部分析法中,需将炉内的传热机理表达成方程式,并要给出某些物理参数,如炉子的几何形状、尺寸;耐火材料的导热率、比热、辐射率;熔融金属的辐射率及热阻等.在现存生产的熔铝炉中,耐火材料是随其使用年限而老化的.金属熔体的辐射率及热阻因炉料氧化形态的不同而随之变化,而且其氧化形态也是不可预知的.因此手册中给出的某些物理参数是不能再引用的,而对这些变化着的参数进行测量也是不切实际的.内部分析法的再一个缺点是其代表性差,对不同几何尺寸的炉子都需确知其模型.
It is also extremely difficult, if possible, to analyze the production conditions of an existing aluminum melting furnace using internal analysis methods, in which internal heat transfer mechanisms need to be expressed as equations and given some physical Parameters such as furnace geometry, dimensions, thermal conductivity, specific heat, emissivity of refractories, emissivity and thermal resistance of molten metal, etc. Refractory materials are aged with existing life in existing aluminum melting furnaces The emissivity and thermal resistance of the metal melt vary with the oxidation state of the charge and their oxidation morphology is unpredictable and some of the physical parameters given in the manual can not be reused, It is impractical to measure the changing parameters.Another disadvantage of the internal analysis method is its poor representation, and it is necessary to know its model for furnaces of different geometries.