Study on the application of active balancing device to solve the vibration problem for the rotor with bending fault

The rotor with bending faults that occurrs on the rotating machinery usually vibrates seriously. This paper investigates to apply the active balancing device on a flexible rotor with bending faults to solve the vibration problem. Two problems are studied by finite element method firstly： Where the balance actuator is fixed on the shaft and how much the balancing capacity of the active balancing device is needed. The experiment is then carried out on the test rig, which consists of a flexible rotor with bending faults. The test results indicate that the bending rotor peak vibration response can be decreased from 550~m to 40~tm below by using the active balancing device. The peak vibration response decreases approximately by 93 %. The synchronous vibration due to the rotor bending faults can be controlled effectively by using ac- tive balancing device. The active balancing device is especially adapted to solve the problem caused by thermal distortion with time-variation and randomness, which is varied with working conditions, thus it has good practical value in practice.     

氮化40Cr制作潜水泵主轴的研究

研究了40Cr钢经辉光离子氮化处理取代3Cr13钢制作潜水泵轴的可行性。讨论了氮化对40Cr钢组织、耐磨性、耐蚀性及变形的影响。结果表明:40Cr钢经辉光离子氮化处理后,与3Cr13钢相比,具有优良的耐磨性、耐蚀性和尺寸稳定性。采用此种工艺制作潜水泵轴,性能上符合要求,而且成本低,具有明显的经济效益。     

大偏心受压构件经济配筋计算方法分析

本文是以新的钢筋混凝土设计规范为依据,提出一种大偏心受压构件强度计算中经济配筋的简易实用方法,文中导出直接简易判别(A_s+A_s′)min的受压区高度x_0,并给出详细的分析图表,具有普遍实用意义。     

扩展式旋风分离器的性能计算

本文阐述扩展式旋风分离器的工作原理.通过一系列实验数据,求得准自由涡区的速度函数,计算分离的粒子的直径和处理的空气量,最后给出算例.     

固定化酵母制备枣酒的条件探讨

本文主要介绍在枣酒酿制中,利用固定化细胞技术,以海藻酸钙为包埋剂,通过添如吐温、甾醇、油酸、棕搁酸提高酵母活性,加快发酵速度,缩短发酵周期。如果胶粒再用明胶与戊二醛交联,可提高胶粒的机械强度,使细胞泄漏减少。连续使用五次,胶粒无开裂现象。     

Study on seal improvement and rotor thrust control of centrifugal compressor

Fluid pressure variations due to process fluctuations or balance drum seal degradation can result in rotor thrust increasing that may jeopardize thrust bearing and compressor’s reliability. Also, the leakage flow through balance drum seal can seriously affect the efficiency of compressor. A method that can improve both the efficiency and reliability of centrifugal compressor is presented. The method focused on rotor thrust control and balance drum seal upgrading. The low leakage feature of Dry-Gas-Seal（DGS）, high reliability of labyrinth, and the feasibility of upgrading existing structure are taken into account at the same time to design a combined labyrinth-dry gas seal system on the balancing drum. Based on the combined seal system, a Fault Self-Recovering（FSR） system for the fault of rotor shaft displacement is introduced to assure the safety and reliability of centrifugal compressor. The modern Computational Fluid Dynamics（CFD） is used to validate this envision. The numerical result and relevant information indicate that the combined sealing system could improve the efficiency of the centrifugal compressor by about 4%.     

氢氧化亚镍的性能与结构之间关系的研究

在Ｘ光衍射（ＸＲＤ）、扫描电镜（ＳＥＭ）、差热（ＤＴＡ）和热重（ＴＧＡ）等测试结果的基础上，对氢氧化亚镍（Ｎｉ（ＯＨ）２）的晶体结构与其性能参数之间的关系进行了研究。研究结果表明，Ｎｉ（ＯＨ）２颗粒的结晶度越高、颗粒的粒径分布越合理，产品的堆积密度越高；Ｎｉ（ＯＨ）２晶体的晶粒越小，产品的电化学活度越高。晶粒大小可以用产品的Ｘ光衍射图中特征峰的半峰宽这一参数来表征。当（００１）和（１０１）晶面的衍射峰半峰宽分别为０．７５°和０．８２°时，产品的活度物质利用率可达９９％，另外，Ｎｉ（ＯＨ）２的热分解温度越高，其活度则越低。     

处理重对称陀螺章动的一种方法

本文侧重从物理上分析陀螺的章动,避免了复杂的数学计算     

在钢模内薄壁钢管弹塑性极限载荷的计算

研究在轴向压力、内压力、挤压力和摩擦力作用下钢模内薄壁钢管弹、塑性变形和内力,计算钢管弹、塑性极限载荷,并讨论钢管和钢模间摩擦系数对极限载荷的影响。最后给出算例。     

蒸汽冷凝水热量回收喷射系统的研究

本文阐述蒸汽冷凝水热量回收的系统框图，建立冷凝器汽——液相转换的热平衡方程、状态方程、不凝气体及喷射蒸汽质量流量的计算公式，研究喷射器在冷凝装置和冷凝水回收泵之间所起的耦合作用，建立喷射器的流体连续性方程、热平衡方程和效率计算的公式，指出克服冷凝后过热水再转变为汽相的技术关键。文中还导出流体在循环回路及经过泵加压后的能量方程，最后给出应用实例的示意图并讨论应解决的技术性问题。