对汽轮机超速问题的思考

汽轮机超速是汽轮机组设备损坏的重大恶性事故,它能使设备损坏,严重影响安全生产。     

推广的离散流体流法及其应用

对离散流体流法作了适当的推广，使其适合于两状态ＭＭＤＰ信源通过ＡＴＭ复接器时的排队分析，然后进一步将它应用于多路Ｏｎ－Ｏｆ信源复接时信元丢失率的估计．仿真和数值计算表明，该方法准确且适于实时运算，将对ＡＴＭ中呼叫接入控制和资源分配产生积极的影响．     

超速压气机的弹塑性仿真研究

根据我国现行增压器压气机叶轮的设计数据及使用要求,采用由参变量变分原理导出的有限元参数二次规划法对某增压器压气机进行了加载、卸载弹塑性变形过程的数值模拟,研究压气机叶轮在不同超速转速下压气机叶轮应力、位移的大小及相应分布规律。     

电梯上行超速及其保护装置研究

随着城市的发展,高楼大厦越来越多,使得电梯的应用也越来越多的部分。电梯作为一种垂直运输设备给我们的生活带来很大便利,它在高层建筑和公共场所已经成为建筑设备不可或缺,可另一方面也发生过由于电梯上行超速而造成的电梯事故,给家庭和社会带来了伤害。如何防止电梯的上行超速成为电梯的设计者和维护者必须要解决的一个问题。     

超速试验机主轴的模态分析与研究

采用有限元分析法对超速转子试验台的模拟转子系统进行模态分析,较全面地分析了整机的振动特性,并根据仿真和试验结果分析了可能造成系统破坏的因素,为试验的动态分析提供理论依据,从而实现设计方案的优化和升级.     

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.     

全液压调节式汽轮机超速原因分析及预防

汽轮机超速事故属于重特大事故,常常致使设备严重损坏,甚至出现人员伤亡,造成巨额经济损失以及恶劣的社会影响。本着预防为主的故障控制理论,相关人员需要熟悉汽轮机调节系统原理,掌握汽轮机组超速事故的征象、原因和预防措施,本文从调节系统工作原理入手,分析了调节系统故障导致机组超速的原因,并有针对性地提出了具体预防措施。