注塑模具冷却管网分析计算

注塑模具冷却管网计算，可以准确预测冷却液的压力和和管网的流量．目前存在两种基本的计算方法都有缺陷；回路法计算烦琐。迭代速度慢；而传统的节点法当管道流量为零时液导矩阵奇异．根据管网基本方程式，建立了新的数学模型。提出了一种改进的节点法．给出了计算程序框图。并编写了电算程序，新方法有效地克服了传统方法的弊端，经实例计算表明，可以快捷准确地进行注塑模具冷却管网的分析计算．     

Numerical simulation on inclusion transport in continuous casting mold

Turbulent flow, the transpor＇t of inclusions and bubbles, and inclusion removal by fluid flow, transport and by bubble flotation in the strand of the continuous slab caster are investigated using computational models, and validated through comparison with plant measurements of inclusions. Steady 3-D flow of steel in the liquid pool in the mold and upper strand is simulated with a finitedifference computational model using the standard k-εturbulence rondel. Trajectories of inclusions and bubhles tire calculated by integrating each local velocity, considering its drag and buoyancy forces, A ＂random walk＂ model is used to incorporate the effect of turbulent fluctuations on the particle motion. The attachment probability of inclusions on a bubble surface is investigated based on fundamental fluid flow simulations, incorporating the turbulent inclusion trajectory and sliding time of each individual inclusion along the bubble surface as a function of particle and bubble size. The chunge in inclusion distribution due to removal by bubble transport in the mold is calculated based on the computed attachment probability of inclusions on each bubble and the computed path length of the bubbles. The results indicate that 6%-10% inclusions are removed by fluid flow transport. 10% by bubble flotation, and 4% by entrapment to the submerged entry nozzle （SEN） walls. Smaller bubbles and larger inclusions have larger attachment probabilities. Smaller bubbles are more efficient for inclusion removal by bubble flotation, so Inng as they are not entrapped in the solidifying shell A larger gas flow rate favors inclusion removal by bubble flotation. The optimum bubble size should be 2-4mm.     

薄板坯连铸保护渣冶金性能实验研究

对5种薄板坯连铸保护渣化学成分、熔化温度、熔化速度、结晶温度和矿物组成进行了试验研究和理论分析，结果表明现行薄板坯连铸保护渣熔化温度为1057～1131℃，熔化速度为19．3～61．1s，结晶温度为1058～1142℃，凝固渣样的矿物组成以硅灰石和少量黄长石为主，且随着碱度的提高，渣样的玻璃化率急剧降低。综合各种性能和工艺要求，渣A除熔化速度需要调整外，其它性能均较适于薄板坯连铸需要。     

Influence of submerged entry nozzle clogging on the behavior of molten steel in continuously cast slab molds

The influence of submerged entry nozzle clogging on the behavior of molten steel in continuously cast slab molds was studied using commercial code CFX4.3. The results indicate that clogging at the top part of the nozzle port not only increases the velocity of molten steel, but also enhances the wall shear stress, F number and heat flux. This clogging has the greatest effect on the behavior of molten steel. However, clogging at the top 1/3 of the nozzle only increases the velocity of molten steel and has little influence. Clogging at the bottom of the nozzle almost has no influence.     

Effects of Rare Earth Oxide on Viscosity of Mold Fluxes for Continuous Casting

The effects of RE (rare earth) oxide on viscosity of mold fluxes were investigated with a rotary viscometer. The results show that : (1) The viscositv of mold fluxes is remarkably inereased by RE oxide addition, especially when the mass fraction of RE oxide is more than 10%. (2) By addition of RE oxide, precipitation of the insohlble particles with high melting point from the molten slag with the decreasing of the temperature leads to the inerease of viscosity. Viscosity curve shows that RE oxide is soluble in some extent in mold fluxes. When RE oxide is in a state of supersaturation, the existence of insoluble particles also makes the viscosity of mold fluxes increase. (3) Not only the viscositv of nlold fluxes can be reduced, but also the capacity to dissolve and absorb RE oxide can be increased by Li2O, B2O3 and BaO. However, the contents of Li2O, B2O3, and BaO should be controlled to suitable levels. (4) The solidification temperature of mold fluxes can be increased by the addition of RE oxide, which is unfavorable to heat transfer and luhrication of mold fluxes between steel shell and mold.     

坚持走产学研结合之路创新高职教育人才培养模式

高职教育人才培养模式的探索和创新,是通过产学结合、工学交替、校企合作的机制来实现的.主要在专业设置与建设、课程体系、教学内容、教学方法和手段、教学管理和人才培养途径等方面进行改革与创新.     

真空吸滤过程影响纸浆模塑制品质量问题的分析

根据实际生产分析了纸浆模塑制品生产工艺过程影响纸浆模塑产品质量问题产生的原因,并总结出解决这些问题的方法,对实际生产具有指导意义.     

薄板坯连铸结晶器振动机构改进分析

介绍了DANIELI薄板坯连铸机结晶器振动机构影响拉速的根本原因，对结晶器振动机构的改进做了详细分析，有效地控制了结晶器振动台的偏摆量，比改进前提高拉速0．4m/min。     

新钢板坯连铸用保护渣的开发

介绍了新钢板坯连铸的凝固特点及对保护渣性能的要求。研制开发出了板坯连铸用保护渣。工业试验表明：研制的保护渣具有良好的使用效果。     

热电偶式风速传感器的非线性动态调校

介绍了以热电偶为检测器件的风速传感器的测量原理,在分析其输出特性的基础上,阐述了一种人工神经网络模型———Adaline模型的网络学习,逼近非线性函数的方法,利用神经网络对风速传感器的非线性进行校正,大大提高了风速的检测精度。