CAJ | 학술논문

分析板材在层冷过程中的传热,建立以热辐射和冷却水对流换热方程为边界条件的偏微分热传导模型,并基于泛函变分原理进行离散求解,获得各离散时间节点上的温度。为进一步提高该温度模型计算精度,在宝钢Gleeble热模拟实验机上测定3种碳钢样本的密度、比热容和热导率等热物性参数随温度变化的函数关系,采用最小二乘法建立回归模型,线性插值后用于温度场定量计算。此外,采用层冷实测温度反算和优化水冷、空冷换热系数,以满足模型现场长期应用的稳定性要求。结果表明,改造后层冷温度设定系统的精度能较准确地反映板材在层冷过程的温度变化,温度模型计算值与实测值吻合良好。
분석판재재층랭과정중적전열,건립이열복사화냉각수대류환열방정위변계조건적편미분열전도모형,병기우범함변분원리진행리산구해,획득각리산시간절점상적온도。위진일보제고해온도모형계산정도,재보강Gleeble열모의실험궤상측정3충탄강양본적밀도、비열용화열도솔등열물성삼수수온도변화적함수관계,채용최소이승법건립회귀모형,선성삽치후용우온도장정량계산。차외,채용층랭실측온도반산화우화수랭、공랭환열계수,이만족모형현장장기응용적은정성요구。결과표명,개조후층랭온도설정계통적정도능교준학지반영판재재층랭과정적온도변화,온도모형계산치여실측치문합량호。
The heat transfer of steels in laminar cooling process of hot strip mill was analyzed and partial differential models were proposed with boundary conditions of thermal radiation and cooling water convective equations.Based on the functional variation principle,the models were solved and node temperature on discrete time was obtained.To further enhance the temperature model calculation precision,thermal material properties including density,specific heat capacity and thermal conductivity were experimentally measured in Baosteel Gleeble thermal simulation equipment for three different carbon steels and the method of least squares was used to statistically derive regression models for the properties.Furthermore,the heat transfer coefficients of water and air cooling were reversely calculated and optimized based on actual measured temperature to meet the long-term stability of the application of the models.The numerical simulation and experimental results show that the setup accuracy of temperature prediction system of ROT was effectively improved.