Structure Optimization Of Multi-crystalline Silicon Ingot Furnace And Its Temperature Field Visualization Analysis

The solar energy, which has made great contributions to solving the energycrisis as well as environmental pollution problems, is regarded as anenvironmental-friendly and renewable clean energy to produce electricity insocial production process along with human life. The quality of silicon ingotproduced by the multi-crystalline silicon ingot furnace is the main material ofsolar cell and directly affects the photoelectric conversion rateof solar cells.Silicon material melted into silicon melt through the heating system in theingot furnace. Silicon melt started to crystallize and grow into silicon ingot dueto the temperature gradient in vertical direction. In the silicon ingots, theminority carrier lifetime, carbon and oxygen and other non-metal impurities aredirectly or indirectly affected by the temperature distribution in the furnace. Thethermal system includes heaters, a crucible, a graphite platform along with heatshields, which comprise a "thermal system". The domestic studies of the thermalsystem of multi-crystalline silicon ingot furnace is relatively little. This papertakes the450kg ingot furnace produced by an enterprise as the research object,carrying on the following research:It is studied that the temperature distribution in the furnace in the process ofthe heating and melting in the450Kg ingot furnace by using the finite element software ANSYS. According to the comparison of simulation results withexperiment results, it can be known that the he simulated model is true. The450kg ingot furnace body is kept unchanged, the crucible size is increased, thelocation of the heater and other thermal structure is changed, so the effectiveheating area is increased. In this way, the450kg ingot furnace is upgraded to550kg ingot furnace. It is studied that the temperature distribution in the furnacein the process of the heating and melting in the550Kg ingot furnace. Thecalculation results show that the silicon material can be completely melted in the550kg ingot furnace, and go on crystallization growth in the next phase. Theshortened melting time of unit mass of silicon material can improve theproduction efficiency and save energy.As a heating part of the ingot furnace, the graphite heater provides energyfor the silicon ingot production. The heating power of the heater is calculatedand checked by calculation. The calculation results show that the heating powerof the heater meets the requirements of the multi-crystalline ingot furnace. Forthermal-electric coupled calculation of the graphite heater by using ANSYSWorkbench software, the maximum temperature and the temperature uniformityof heater comply with the requirements of the equipment.Heat insulation cage, as an important part of the thermal system ofmulti-crystalline ingot furnace, is mainly used to support, fix heat shield andcontrol of the lifting movement of heat shield. If the deformation of heatinsulation cage exceeds a certain degree, it will cause the linear guide raildistortion, which would damage the insulation cage lifting mechanism. Thispaper is aimed to optimize the structure of heat insulation cage. And thethree-dimensional model of the thermal insulation cage of the thermal-structurecoupling were calculated by ANSYS Workbench software. Before and after thestructure optimization, the temperature distributions in the thermal insulationcage are basically same. But the maximum thermal deformation of the optimizedthermal insulation cage is obviously reduced, and the deformation is well distributed. The optimization of the thermal insulation cage structure hasobvious effect, which is beneficial to improve the service life of the thermalinsulation cage.