含钛高炉炉渣微波合成碳化钛及其介电性能测定

The preparation of functional material titanium carbide by the carbothermal reduction of Ti-bearing blast furnace slag with microwave heating is an effective method for valuable metals recovery; it can alleviate the environmental pressure caused by slag stocking. The dynamic dielectric parameters of Ti-bearing blast furnace slag/pulverized coal mixture under high-temperature heating are measured by the cylindrical resonant cavity perturbation method. Combining the transient dipole and large π bond delocalization polarization phenomena, the interaction mechanism of the microwave macroscopic non-thermal effect on the titanium carbide synthesis reaction was revealed. The material thickness range during microwave heating was optimized by the joint analysis of penetration depth and reflection loss, which is of great significance to the design of the microwave reactor for the carbothermal reduction of Ti-bearing blast furnace slag.     

中间辐射体对加热炉内传热过程影响的数值模拟

针对黑体定向辐射技术节能的机理问题，以实验室规模具有中间辐射体的室状加热炉为研究对象，建立了具有中间辐射体的物理模型，以CFD商业计算软件Fluent建立平台计算黑体定向辐射条件下的气体流动、传热、燃烧的三维耦合数学模型，并根据实验结果对数学模型进行验证.研究结果表明:中间辐射体的加入改变了炉体燃烧室内的流动情况及炉墙对钢坯固体辐射的比表面积，分别从气体辐射及固体辐射角度增强了钢坯表面辐射换热强度，燃烧温度降低20K左右，钢坯加热速度提升16.7%，钢坯表面最高温度提升40K.加热效率的提升带来了更好的节能效果.     

Persistent anomalous flows over the subtropical western Pacific in summer

The distribution of global persistent anomaliesshows that the subtropical western Pacific is a key region with high-frequency occurrence of persistent anornalics. Analyscs of streamfunction anomalies, 013 anomalies etc. suggest that the convective heating related to Indian nlon.uwn might he responsible for the development of WPA. The results of numerical experiment by two linear bamtmpic rnodcls support the observation.     

蒸汽供热管网的动态仿真建模

为建立供热管网的在线优化运行、故障实时诊断以及仿真分析和培训系统 ,必须建立一种高精度的蒸汽供热管网动态仿真模型。该模型将蒸汽处理成为单相可压缩流体 ,将管网处理成为由节点和支路组成的一种网络结构。在仿真计算中 ,采用隐式 Euler算法、线性迭代方法和稀疏矩阵算法求解由物理模型所得的非线性微分方程组。证明了所用的算法具有大范围收敛特性。此方法将被应用于青岛市蒸汽供热管网的工程项目中     

扩展的小增益定理

把接受瞬时信号的系统成立的结论推广到接受持久信号的系统,一直是鲁棒控制的基本问题,也是一个难题。在接受持久信号的系统中,很多原有的接受瞬时信号系统成立的结论都不成立了,因此大量的概念、定理需要改进。目前虽然对于一般的H∞函数和H∞不确定性模型来说,定义频域的概念已取得了一些成果,但是对于小增益定理的改进还是很少。基于此,应用H-∞1函数空间修改了小增益定理,给出了一个扩展的小增益定理。并且讨论了它的应用价值。     

织针淬火加热过程中温度场的计算机模拟

针对网带炉织针淬火,在考虑加热过程中换热系数及各种物性参数随温度变化的情况下,运用有限元法建立了二维平面非稳态温度场的计算数学模型。加热曲线的计算结果与实际测量结果吻合较好,表明本数学模型和计算程序能够正确预测织针温度场的变化,从而有助于不同类型的织针在淬火过程中加热温度的控制及淬火工艺的改进。     

防喷器电磁加热保温装置设计

利用非稳态传热数学模型计算了防喷器的瞬态温度变化情况,并确定了电磁加热装置的加热功率。同时根据实物测绘结果设计、加工了一套修井作业装置防喷器电磁加热保温系统。结果表明,防喷器表面温度非稳态变化的数值模拟结果与现场测试值吻合较好,所设计制造的防喷器电磁加热保温装置满足了冬季修井作业要求,具有升温快、保温效果好、安全便捷的优点。     

薄层油页岩电加热原位改性温度场数值模拟

原位开采是油页岩未来主流开采技术,目前油页岩原位开采技术研究对象多为厚层油页岩,但中国存在大量的薄层油页岩,故研究薄层油页岩原位电加热温度分布规律具有重要的意义.针对中国特殊薄层油页岩结构,采用ANSYS软件中瞬态热分析模块,建立薄层油页岩原位电加热模型,研究加热5年内薄层油页岩中温度场分布.仿真结果表明:油页岩的有效加热体积随加热时间增加而增大,且加热前3年增加速度显著快于3年之后,加热3年后继续加热增热效果已不明显,故加热薄层油页岩在加热3年可以使利益最大化.研究结果为中国薄层油页岩的开发提供了数据支撑.     

Non-Fourier Heat Conduction Effects During High-Energy Beam Metalworking

Non-Fourier heat conduction induced by ultrafast heating of metals with a high-energy density beam was analyzed. The non-Fourier effects during high heat flux heating were illustrated by comparing the transient temperature response to different heat flux and material relaxation times. Based on the hyperbolic heat conduction equation for the non-Fourier heat conduction law, the equation was solved using a hybridmethod co mbining an analytical solution and numerical inversion of the Laplace transforms for a semiinfinite body with the heat flux boundary. Analysis of the temperature response and distribution led to a criterion for the applicability of the non-Fourier heat conduction law. The results show that at a relatively large heat flux, such as greater than 108 W/cm2, the heat-affected zone in the metal material experiences a strong thermal shock as the non-Fourier effects cause a large step increase in the surface temperature. The results provide a method for analyzing transient heat conduction problems using a high-energy density beam, such as electron beam deep penetration welding.     

带有ABS系统的汽车制动效能的研究

基于制动过程的能量转换及摩擦生热,通过对盘式制动器实际工作条件的分析和理论计算,建立了紧急制动过程中制动盘与摩擦片瞬态温度场分析的有限元模型.采用直接热力耦合有限元方法来分析制动器摩擦热的产生及其温度的瞬态分布.讨论在汽车制动时ABS系统对汽车制动效能的影响.     

Study of rapid transient explosive boiling under short-pulsed laser heating

Using acetone, ethanol, water and acetone-water mixture as test liquids, the rapid transient explosive boiling (RTEB) taking place under short-pulsed laser heating is observed in experiment. The behaviors of temperature variation are investigated via transient temperature measurement. The vapor bubble behaviors of RTEB are captured by high-speed photography, and the difference between RTEB and normal boiling is analyzed. The boiling heat transfer of RTEB is also discussed. It shows that the character of RTEB is far different from normal boiling.     

Three-dimensional investigation of velocity skin effect in U-shaped solid armature

A three-dimensional transient computational model is applied to investigate the velocity skin effect （VSE） in a U-shaped solid armature. With this model, current and heat transport in the armature can be evaluated accurately. The results show a local concentration of current and joule heating at the interface, and significant damage occurs at the edges of the armature. It is also observed that there is significant enhanced heating at sharp corners because of the armature geometry. The three-dimensional model can efficiently capture the salient features of the physical phenomena at the rail-armature interface, and contribute to the development of the armature design.     

Temperature monitoring and heating optimization in cancer hyperthermia

A closed form analytical solution to the Pennes' equation with random heating was obtained using the Green s function method. To meet the requirements for the tumor killing temperature and the skin bum threshold, an approach to optimize the cancer hyperthermia parameters was proposed. For clinical practices, a solution to reveal the relationship between skin surface temperature and the transient temperature inside the tissue was obtained. Parametric study shows the feasibility of the heating optimization. The present approach can be incorporated in the apparatus to es¬tablish a noninvasive hyperthermia system.     

火烧油层注气加热过程的模拟计算研究

在火烧油层的注气加热过程中,需要根据点火需求优化注气参数。考虑了空气在井筒、油层的流动及换热过程,包括空气进入油层的混合过程、水蒸发进入空气和湿空气降温后凝结为水的组分及相态变化、油层之间的导热过程,建立了相应的瞬态模型,提出了基于龙格库塔法的求解方法。利用该模型及求解方法进行了模拟注气验证,并用于油田的实际火烧油层点火过程的监测系统。研究表明：点火过程中加热带扩展速度非常有限（6 d 后加热带半径仍小于0.6 m）,并且受油层中含水率影响较大,加热带温度主要受电加热器功率和注气速度影响,受注气时间长短影响较小。点火过程中应保持电加热器功率和注气速度稳定。     

核电水泵在热冲击下瞬态热效应的研究和分析（Ⅱ）──三维时变有限元分析和计算

本文首先推导了非耦合热传导方程和拟静态热弹性运动方程的有限元求解公式；然后，根据核电水泵的结构及其性能参数，估算出了水泵不同区域处的对流换热系数；最后，在进行了大量的试算工作和有关数值考核计算的基础上，采用三维时变温度场、热应力和热变形场有限元分析方法，详细考察了核电停堆冷却泵在受热载冲击下各瞬时的瞬态温度场及热应力、热变形场的分布状况和变化行为．本文的研究工作初步形成了对核电水泵机组在热冲击下的瞬态热效应分析的研究方法；同时亦为最终替代代价昂贵的实物实验提供了坚实的理论基础和关键的计算手段．     

基于深度确定性策略梯度的热力站一次侧优化控制

针对热力站供热量与需求量不匹配的现象,提出一种基于深度确定性策略梯度(DDPG)的热力站一次侧优化控制方法。采用LSTM(long short term memory)算法对热力站进行建模,然后结合集中供热系统运行机理,使用DDPG控制算法对热力站一次侧供水流量序列求解。运用包头某热力站的大量历史工况数据,进行仿真实验,结果表明该方法的有效性,一定程度上实现了热力站的按需供热,提高热量的利用率。     

感应加热中间包夹杂物的运动及去除

针对某钢厂双通道式感应加热中间包,建立了三维非稳态数学模型来研究感应加热中间包内夹杂物的运动行为和去除率.从力平衡原理出发,采用欧拉-拉格朗日方法分析了感应加热中间包内夹杂物的运动行为.建立了感应加热情况下夹杂物碰撞长大的数学模型,考察了夹杂物碰撞长大对其去除率的影响.结果表明,钢液流过通道受到紧箍作用,夹杂物会受电磁压力作用而向通道壁面运动,有利于夹杂物的去除;碰撞长大能够显著提高小粒径夹杂物的去除率;感应加热有助于夹杂物的去除,尤其是小粒径夹杂物.     

测量低温下固体热物性的一种非稳态方法

介绍了测量低温下固体热物性的一种非稳态方法，并对玻璃钢试样的热物性进行了测量，所测数据与其他所测数据相比，有较好的一致性。     

脉冲热流作用下球体内的非傅立叶热传导

分析了球形物体表面遭受一随时间变化脉冲热流时的双曲型非傅立叶热传导问题．给出了此类超急速传热情形下的热传导方程、边界条件及初始条件的无量纲形式,采用Ｌａｐｌａｃｅ变换技术,求得了任意时刻球体内部温度分布的解析解．作为算例,计算了方波脉冲这类随时间变化热流作用下球体内的温度变化,结果表明,该类超急速热传导问题与常规的傅立叶热传导相比具有明显不同的特征     

能量守恒定律在液压系统发热分析中的应用

本文从能量转换和守恒的角度分析了液压系统的能量转换过程 ,对液压系统的发热机理进行了研究 ,指出了压力损失是液压系统发热的重要原因 ,并通过实验验证了理论分析的正确性。这一结论对液压系统的设计分析具有重要意义