| Industrial furnace is commonly used heating equipment, it is very important to design and optimize the furnace. In this paper, it simulates and optimize the heat transfer characteristics of the core of the resistance furnace detailed. Specific studies in the following areas:1 the research of the electric heaterThis article studies the electric heating from the electric structure, size, and the surface temperature of the three aspects. The inside and outside temperature is distributing more uniform, when the cross-section of the electric heating is the circular ring. When D>5cm, the internal and external difference in temperature of circle rods and square rods is higher, but tube electricity heat body stand opposite each other lower. The surface temperature affects the electric heating rods obviously. When radius is a certain value, it is the approximate to last square relation between with difference in temperature and external surface temperature. When the outer surface temperature is a certain temperature, the heating temperature difference with a radius of the increasing rise2 Under the conditions of high temperature electric heating three-dimensional steady-state simulate the macromolecular particles containing impurities in the graphite heating materials. It's finding that the current is greatest impact the heat of the graphite containing impurities. For silicon carbide particles, the greater the current, the greater the temperature difference between the particles, and temperature difference is directly proportional to the square with the current relations. When the current is 20 A/mm2,the temperature difference has reached 35℃. In addition to Current, the impurities in the size of particles also directly affect the temperature of the electric distribution. In addition to Current, the size of particles also directly affects the temperature of the electric distribution. 3 This paper studies the heat transfer characteristics of variety of electric heating elements, under the unsteady-state status. For the Tubular electric heating elements, internal insulation materials affect the velocity of calefactive and the inner distribution of temperature on the electric heating. For J GQ style tubular electric heating elements, pinched heating elements under the surface reached to 70℃, the time spent significantly less than the state did not pinched , another is the temperature of loosen heating elements is higher obviously than that pinched circumstances. For the graphite electric element, at the condition of radiating outside of heat, the temperature of the graphite electric element is absent quickly. The heating rate is relative to the density. According to simulation, the temperature distributed equality, so receive the relative is: When the density is small, the result of calculation and simulation result are identical. For the graphite electric element which has crack on the surface, the exist of the crack are effect the heat rate very much, the exist of the crack causes the decline of the heat rate. a 10mm- diameter graphite electric element, a second latter, the temperature reach 524.95℃if there is no a crack .But it highest temperature is 434.587℃when there is a crack. At the round of the crack the temperature is smaller than the main body of the graphite electric element. There is a big difference in temperature, which result the heat stress. The existence of the crack in tubular graphite electric element result the un-equality of the element temperature For a 10mm-deepth tubular graphite electric element, when the temperature of the crack achieve to the work temperature, the temperature of the body is at only a small point(about500℃).So if continues to heat the temperature of the body has not reach the work temperature, the crack temperature has exceed the melting point.
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