基于CFX的液力偶合器水介质流场数值分析

分析CFX在CFD仿真过程中的原理,液力偶合器气液两相,不可压缩、三维不稳定湍流流动的特性。给出了对气液两相设置、交界面动坐标系设置、壁面设置以及湍流模型的原理分析。并对准562桃形腔水介质不同充液率和不同转速比的流场进行数值计算,对比流场压力分布云图、叶片表面受压云图以及流道中间截面速度矢量分布云图,总结出液力偶合器内部流场流动为环流流动的特点,并且随着充液率增加,输出转矩逐渐增大。     

机械搅拌式浮选机的流体动力学分析

利用计算流体动力学分析软件Fluent模拟计算机械搅拌式浮选机的内部流场。计算结果标明,矿浆在槽体内螺旋上升和螺旋下降的循环流动,存在流动死区和短路现象,湍流强度分布呈现对称性,最大湍流强度出现在叶片流道内,进出口对其影响不大。     

DSM重介质旋流器流场的数值模拟

采用计算流体力学软件,选用RSM湍流数值计算模型,对DSM型重介质旋流器的流场进行了数值模拟.研究了DSM型重介质旋流器流场的速度分布、密度分布和压力分布,得出4点结论：旋流器内的流体沿着溢流管的外侧向下流动,使旋流器分选时存在短路流,降低了旋流器的分选效率.旋流器内的轴向速度越接近中心越高,大约在旋流器半径的中部通过零点,所有速度为零的个点形成了零轴速包络面（LZVV.旋流器内的切向速度从内向外逐渐升高,在空气柱附近达到最大值,然后逐步下降到最低点.由于回流的作用,在旋流器中间造成负压区形成了空气柱,空气柱截面直径大约为溢流口直径的0.6倍.     

基于数值计算的浮选机内颗粒流动行为研究

浮选机内矿浆动态流动性能研究对于优化浮选机具有重要意义。利用CFD数值模拟方法研究了浮选机内矿浆动态流动特性,并讨论了不同粒径矿石颗粒的分布特点,矿浆的动态流动并未破坏浮选机的循环流场结构,固相颗粒也形成了循环特征流场。单一固相粒径分析表明,随着给矿粒径的增加,浮选机槽底的沉积现象加重。多固相粒径分析表明,浮选机对不同粒级颗粒的提升能力和搅拌混合能力是不同的,为提高粗颗粒的回收能力,需要提高颗粒的提升高度。     

XJM-S型浮选机流场的试验研究

运用PIV粒子成像测速技术对XJM-S型8L实验室浮选机模型流场进行了试验研究,分析了浮选槽内流场的运动规律:该浮选槽内不同区域存在循环流、旋转流和上升流等错综复杂的流动状态;沿垂直方向,在浮选槽的下部以循环流为主,上部以上升流为主;沿水平方向,中心区域以循环流为主,周边区域以旋转上升流为主。该流动状态符合浮选过程要求。     

基于Fluent的对旋轴流通风机内部流场分析

利用Gambit建立对旋通风机数值模拟模型和计算网格,在Fluent软件平台上,采用Interface边界条件处理计算模型中不同区域间的交界面,SIMPLE算法耦合压力速度,Segregated隐式算法求解Navier-Stokes方程,在定常条件下对对旋通风机内部流场进行了全流道数值模拟。同时结合模型机的试验结果,模拟预测了模型机的气动性能,得到内部流场速度分布情况、压力分布状况和湍流强度分布特点,揭示了对旋通风机的内部流动特征。可为对旋通风机流道设计及内部流动控制提供参考依据。     

基于Fluent的对旋轴流通风机内部流场分析北大核心

利用Gambit建立对旋通风机数值模拟模型和计算网格,在Fluent软件平台上,采用Interface边界条件处理计算模型中不同区域间的交界面,SIMPLE算法耦合压力速度,Segregated隐式算法求解Navier-Stokes方程,在定常条件下对对旋通风机内部流场进行了全流道数值模拟。同时结合模型机的试验结果,模拟预测了模型机的气动性能,得到内部流场速度分布情况、压力分布状况和湍流强度分布特点,揭示了对旋通风机的内部流动特征。可为对旋通风机流道设计及内部流动控制提供参考依据。     

基于FLUENT的静态充填混合器流场分析

针对用高水膨胀材料和浆料管道自流输送设计出静态充填混合器。利用计算流体力学的方法和多相流理论,建立浆料在混合器内的流动控制方程,在三维软件中建立流体模型进行数值计算。通过分析混合器内流场在各个方向的不同截面,得出浆料入口与混合器底部距离为1 m时最有利于浆料均匀混合,其流场涡流数量多且均匀,速度适中,湍流强度高,各截面均有混合效果,出口不容易堵塞。     

XJM-S8型浮选机数值模拟及槽内矿浆流态分析

利用Fluent软件模拟了XJM-S8型浮选机的三维流动状态,分析了XJM-S8型浮选机的流场特性,结果表明:XJM-S8型浮选机槽内流动状态呈"W"形立体循环运动,符合浮选过程要求;在稳流板导向作用下,流体沿水平断面分布均匀,无死区,浮选机结构合理。     

高翼螺旋钻杆内部气固两相流动数值分析

为了揭示高翼螺旋钻杆内部气固两相流动规律,采用Euler-Euler模型,对高翼片螺旋钻杆颗粒输运过程进行气固两相流数值计算,得到高翼片螺旋钻杆在不同转速下内部气体和颗粒两相的速度和压力分布规律。数值计算表明,在400 r/min时,截面内部速度分布和压力梯度均匀,转速为600 r/min时,在轴向中间截面产生压力不连续现象,截面内局部发生压力突变,此时内部流场分布紊乱。螺旋钻杆内部压强由进口到出口呈近似线性增长的趋势,转速越高,压力梯度越大,进出口压差也就越大,随着转速增大,螺旋钻杆中间截面速度依次增大,且静止域中速度明显高于旋转域的速度分布。随着转速增大,颗粒相速度依次增大,颗粒相的最大速度小于连续相最大速度。当转速为400 r/min时,颗粒相主要分布在静止域转筒壁面附近,螺旋钻杆内部颗粒分布较少,在惯性力作用下颗粒贴附在螺旋钻杆壁面螺旋推流,颗粒体积分数较为均匀,推流效率较高。当转速为600 r/min时,静止域内部中间位置转筒壁面附近颗粒体积分数较高,螺旋钻杆内部气固两相流动分布极不均匀,表现出显著的气固两相流动不稳定性。     

Current situation and future trend of China rare earth luminescent material industry

<正>Rare earth luminescent material is one of the most important application sectors of rare earths.China enjoys the exceptional advantage to develop rare earth luminescent material for its abundant rare earth resources.After several decades'endeavor,China's rare earth luminescent material industry,headed by rare earth phosphor for lamp and LED and high efficient rare earth energy-saving light source,has been gradually developed into a scale industry.China has become a major production base of rare earth phosphor for lamps and rare earth     

China rare earth market review

正June 1~10,2014Rare earth market remained weak.Quoted price of rare earth products was similar to that in May.There was no sign of recovery in downstream market.The market of NdFeB magnetic materials and phosphor was depressed.Catalyst,polishing powder and ceramic industries remained inactive.Demand from downstream industry was soft.Consumers purchased on their needs.Suppliers had strong intention to sell.Prices of rare earth products     

Annual Report analysis of Chinese rare earth-related listed companies in 2013

<正>Chinese rare earth-related listed companies have published their 2013 annual reports.It can be understood from their reports that production and operation activities of Chinese rare earth-related companies were still heavily affected by macro economy and industrial policies.They basically followed the steps of national economy.In 2013,world economy recovered slowly but the economy     

Market opportunities and challenges for rare earth polishing powder

正1.Status of rare earth polishing powder Rare earth polishing powder with high content of cerium oxide began to replace iron oxide for glass polishing and became one of the key materials in glass polishing process since 1940.Compared with traditional iron oxide,rare earth polishing powder has many advantages,such as fast polishing rate,high polishing quality and long service life.It can achieve good surface quality and improve operation conditions.For example,in lens polishing,the polishing work that cerium     

Baotou Research Institute of Rare Earths developed a new RE alloy preparation technology

正Pyrometallurgy Laboratory of Baotou Research Institute of Rare Earths had independently developed a new preparation technology of rare earth alloy for NdFeB.The alloy can remarkably enhance the coercivity of NdFeB magnet but also evidently reduce the production cost of the magnet.The new master alloy was prepared in the kA pilot-scale electrolytic cell by the independent technology.The rare earth master alloy can be used as the raw material for NdFeB.Compared     

矿用防爆轴流对旋主要通风机叶片ANSYS模态分析及应用

高效节能矿用防爆对旋主要通风机的叶片是主要通风机运行的关键部件,叶片在运行时不断受到气流的作用力,从而使叶片产生振动,当叶片振动的频率与叶片的固有频率接近时,容易产生共振从而导致叶片的断裂。一旦叶片断裂时,对主要通风机的安全运行产生致命的影响,从而导致矿山、化工等企业发生重大事故,将会产生不可估量的损失。基于有限元分析软件ANSYS,对高效节能矿用防爆轴流对旋主要通风机叶片进行模态分析及产生对应的六阶模态频率,对主要通风机叶片的运行频率、固有频率及产生的共振问题进行了原理分析,并且解决了叶片频率共振的问题,从而为主要通风机叶片结构设计提供理论依据,并对主要通风机叶片的安全运行提供保障。     

2013 NdFeB export analysis

<正>China totally exported nearly 24,000 tonsof NdFeB products during 201 3,including 18,825 tons of permanent magnet,valued USD 1.34 billion at an average price of 71.4 USD/kg;3,277 tons of NdFeB magnetic powder,valued USD 1 01 million at an average price of 30.9 USD/kg;1,334 tons of strip casting ribbon,with total export value of USD 74million at an average price of 55.3 USD/kg;and 586     

Market and recycling of NiMH battery

<正>Market status and future trend of NiMH battery1.Global market of small NiMH battery Global market size of small NiMH batteries declined year on year since 2011.The trend will continue to 2018,at the rate of 5%to 10%annually.Demand for small NiMH batteries will be stable gradually.Many electrical apparatuses are powered by the built-in lithium battery today,which is the main reason for the shrunk market of small NiMH batteries.But,for some products,small NiMH     

China rare earth market review

正September 1-10,2014 Affected by the National Day holiday,rare earth transaction was stagnant and the market showed a weak steady state.As there was no good news for downstream market,some products with flat demand would likely rally slightly for some time to     

唐口煤矿深部复杂开采工作面瓦斯分源涌出规律研究

研究工作面瓦斯涌出规律对工作面瓦斯治理有重要意义。为了得到唐口煤矿深部3号煤层复杂开采条件下工作面回采时期瓦斯涌出时空演化规律,选取6304工作面作为对象,采用实测方法研究6304工作面瓦斯涌出规律。结果表明:6304工作面瓦斯涌出量为6.534 m³/min,其中煤壁占34.27%,落煤占29.62%,采空区占36.11%;沿工作面倾向由低到高,瓦斯浓度整体为上升趋势,其中1—76号架工作面瓦斯浓度小于0.20%,76—102号架瓦斯浓度上升明显,最大为0.387%;上隅角的后部采空区是工作面的瓦斯主要涌出源,上隅角1号测点瓦斯浓度0.78%,上隅角周边3号、5号、7号、8号、9号测点瓦斯浓度平均为0.643%;周期来压时,上隅角瓦斯相对平时较高。研究为针对性的瓦斯分源监控与灾害防治提供基础。