耐火材料物性参数对脱硫喷枪热应力的影响

Effects of property parameters of refractories on thermal stresses of desulphurizing lance

应用有限元法对某混铁车铁水脱硫喷枪的工 作温度场与应力场进行了动态仿真,分析了喷枪用耐 火材料物性参数(热导率、热膨胀系数和弹性模量)对 喷枪最大热应力的影响。结果表明:喷枪的最大热应 力与喷枪耐火材料的热导率呈对数函数关系,即当热 导率较小(<2W·(m·K)-1)时,其对最大热应力的 影响较大;当热导率较大时,对最大热应力的影响变 小。喷枪的最大热应力随喷枪耐火材料的热膨胀系数 变化的规律为一条高次曲线,热膨胀系数约为1.0× 10-5K-1时,最大热应力的值最小;喷枪的最大热应力 随耐火材料的弹性模量的提高而线性增大。

The temperature field and stresses field of desulphurizing lance were dynamically simulated with finite element method (FEM) to show the dynamic thermal stresses distribution within lance in a duty cycle,the effects of property parameters such as thermal conductivity,thermal expansion coefficient and elastic modulus of refractory on the maxmium thermal stresses of desulphurizing lance were researched.The results show that there is a logarithmic relationship between the maximum stress of injection lance and thermal conductivity of the refractory,with increasing of thermal conductivity of refractory the maximum thermal stress increasing rapidly firstly and then tends to stable.That means the effect of thermal conductivity on thermal stress becomes smaller when the thermal conductivity of the refractory is larger.The relationship between the maximum thermal stress of injection lance and the expansion coefficient of the refractory material can be illustrated with a high-order curve.When the expansion coefficient is about 1.0×10 -5 ℃ -1,the thermal stress is minimum;And the maximum thermal stress of the injection lance has linear relationship with elastic modulus of the refractory.