低温制冷机高速反转的故障分析与排除

<正>我们在维护空军某制氧站的一台KL-15型移动式制氧制氮车的工作中,为测试制氧机的工作性能,就其主机ZL-2.8/194型回热式制冷机进行试车,在检测项目完成后正常停车时,制冷机高速反转约3分钟左右,为此我们进行分析查找。     

KL-15型制氧制氮车冷却系统的改造

文章分析了KL 15型制氧制氮车冷却系统在使用地面冷却水时流阻增大 ,使回热式制冷机的水量信号装置不能正常工作的原因 ,并提出了改进方法和注意事项。图 3     

KL-15型制氧车流程分析与改进

KL-15型制氧车是我国自行设计的第一种移动式制氧制氮设备,它采用回热式制冷机作为冷源,配备了板式换热器、分子筛吸附器和自动工作无阀门液氮汽泡泵等部机,可以生产液氧、气氧、液氮、气氮四种产品;具有结构紧凑、机动灵活、适应性强、自动化程度高、操作轻便安全等优点,曾获全国科学大会奖。通过十多年的生产和使用实践,发现该机尚有一些不尽完善之处,有必要通过技术改造,提高性能,降低消耗,改进质量,本文着重谈谈KL-15型制氧车在工艺流程上存在的问题和改造试验情况。     

回热式制冷机机油控制技术鉴定会在杭召开

<正>1984年6月空军航空工程部在杭州组织召开了“回热式制冷机机油控制技术鉴定会”。参加会议的有浙江大学、西安交通大学、空军后勤学校、杭州制氧机研究所的有关教授、专家、科技人员及空军驻各地有关工厂的军代表、杭州制氧机厂的工程技术人员与KL-15型制氧制氮车使用部队的代表。     

杭州制氧机厂回热式液氮、液空设备技术参数

<正>杭州制氧机厂生产的YDS-4型、KLN-20Y型液氮设备和YLK-6型液空设备,是采用逆向斯特林循环制取冷量的低压流程液化设备。它主要由分馏塔、回热式制冷机、热风鼓风机及真空泵组成,并备有杜瓦容器。其中回热式制冷机专门为分馏塔提供冷量。YLK-6型液空设备不需分馏塔。介质气体压缩、膨胀、热交换整个封闭循环都汇在回热式制冷机内进行。生产的冷量使经过净化了的空气在分馏塔内精馏,分离成氧气和氮气。氮气上升吸到制冷机冷凝器冷凝成液氮,其中一部分作为产品输出。技术参数如表所示。     

《回热式气体制冷机1984年国际学术讨论文集》征订通知

经国家批准，定于1984年6月18日至20日在上海举行回热式气体制冷机国际学术讨论会。会议受中国制冷学会的委托，由上海市制冷学会和上海交通大学、上海市科协举办，并得到国际制冷学会、日本、英国、加拿大等的赞助。会后将出版会议论文集。该论文集内容有：1．有关气体制冷机的国际研究动态，2．回热式气体制冷机的设计；     

回热式制冷机氢气介质漏气的检查

<正>回热式制冷机在11091、11093、11090的制氧、制氮设备上,作为提供冷源的主要部机,使用已相当广泛。由于该机在国内使用中绝大多数用户以氢气作为工作介质,氢气分子相对其它气体分子的体积小,所以在使     

一起气体制冷机无油压不能开机的故障引发的思考

通过一起ZL-2.8/194型回热式气体制冷机故障的分析和排除,总结出装(设)备使用维护的责任心问题和设备故障分析与排除的一般思路.     

回热式制冷机产冷量不足的原因及改进措施

针对制氮设备回热式制冷机产冷量不足的现象,分析了原因,并采取了相应措施,从而保证了制氮设备的液氮产量。     

费利浦斯式小型液氮装置介绍

1954年荷兰费利浦期研究所发表了有关回热式制冷机的文献,引起了制冷工作者极普遍的注意,井也由于回热式制冶机的创造,费利浦斯公司又制造了一种小型轻便的液氮装置.这种液氮装置的特点是(1)结构与机组简便,不需要一般空分设备所必须的干燥器,     

Strength analysis of a split sleeve in a pipe containing a defect

We study the decrease in the strength of a pipe containing an artificial defect. On the basis of the analytic and numerical models, we consider the influence of the structural features of a split sleeve on its load-carrying ability. We also analyze the joint operation of a sleeve and a pipe containing an artificially made axial surface defect. The results of the numerical analysis are compared with the experimental data. Translated from Problemy Prochnosti, No. 2, pp. 102–111, March–April, 2009.     

Calculation of a transient in a two-pole network with a thermistor

An analytical expression is derived which describes the variation of the thermistor temperature during a relay-effect transient process following an instantaneous change in the supply voltage in an R — R_T two-pole network.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 38, No. 3, pp. 465–472, March, 1980.     

Stress analysis of a strip with a step and a crack

Stress analysis for a strip of which widths are different at the right and left handsides is carried out for before and after occurrence of a crack at a corner of a step. The strip is analyzed as a thin plate bending problem subject to transverse bending and torsion, and as a plane eleastic problem subject to bending in the plane and uniaxial tension. The rational mapping function of a sum of fractional expressions and complex variable method are used. Stress distribution and stress intensity factors are obtained.     

Interaction between a liquid and a cylindrical body touching a wall

An exact solution is obtained for the problem of interaction between the ideal liquid homogeneously moving at infinity and streamlining a round cylinder touching a solid wall.     

Dispersion of a solute in a Poiseuille flow of a viscoelastic fluid

Gill and Sankarasubramanian's analysis of the dispersion of Newtonian fluids in laminar flow between two parallel walls is extended to the flow of non-Newtonian viscoelastic fluids (known as Phan-Thein-Tanner (PTT)). Using a generalized dispersion model which is valid for all times after the solute injection, the diffusion coefficient K_i(t) is obtained exactly and numerically for linearized and exponential forms of the PTT fluids, respectively. The analysis leads to the novel result for K₁ and K₂(t) (which is a measure of the longitudinal dispersion coefficient of the solute). It is found that the value of K₂(t) depends on the value of Deborah number (De=a measure of the level of elasticity in the fluid) whereas the value of K₁ is constant in both cases. Finally, the effect of the Deborah number on the axial distribution of the mean concentration θ_m is investigated in detail.     

Imaging a point to a line with a single spherical mirror

Methods for imaging a single point source to a line image are discussed, and a design study of single spherical mirror systems that form aberration-free line images is presented. An expression forthe ray density along the line image is derived for such systems in the cases of (i) uniform beam profiles and (ii) Gaussian beam profiles. The resulting ray density profiles are illustrated for single spherical mirror systems over a wide range of design parameters.     

Influence lines for bending under a ring load of a free shell,a shell embedded in a soft medium and a shell containing a soft core

Summary Theoretical expressions for stresses and displacements have been derived for bending under a ring load of a free shell, a shell embedded in a soft medium, and a shell containing a soft core. Numerical work has been done for typical cases with anElliot 803 Digital Computer and influence lines are drawn therefrom.

---

Einflußlinien für die Biegung einer freien Schale, einer Schale in einer weichen Bettung und einer Schale mit weichem Kern

Zusammenfassung Für die Biegung einer freien Schale, einer weich gebetteten Schale und einer Schale mit weichem Kern unter einer Ringlast werden Ausdrücke für die Spannungen und Verschiebungen hergeleitet. Die Ergebnisse wurden für einige typische Fälle mit einem DigitalrechnerElliot 803 numerisch ausgewertet. Die sich ergebenden Einflußlinien wurden graphisch dargestellt.

---

Nomenclature A (),B () Functions of - a, t Mean radius and thickness of the shell - E _S , _S Young's modulus andPoisson's ratio of the shell - G _c , _c Shear modulus andPoisson's ratio of the casting or core - I ₀ (r),I ₁ (r) ModifiedBessel functions of the first kind and order zero and one respectively - K ₀ (r),K ₁ (r) ModifiedBessel functions of the second kind and order zero and one respectively - p Ring load, lb/in - U, W Displacement components in the casing or core in thez andr direction - u, w Displacement components of a middle surface point in the shell - _r , _rz Radial and shearing stress components - Independent variable of infinite integrals - k [3(1–S ²)a ²/t ²]^1/4 With 13 Figures     

聚醚砜四元制膜液体系的相图计算

以Ｆｌｏｒｙ－Ｈｕｇｇｉｎｓ理论为基础，对ＰＥＳ－ＰＧ－ＮＭＰ＿Ｈ２Ｏ＿）聚醚砜丙二醇－Ｎ－甲基－２－哟咯烷酮水）四元制液体系的相图进行了计算，利用三元相图考察Ｈ２Ｏ和ＰＧ对液－液相分离的影响，在三元的理论的基础上提出了低分子量添加剂的卤元改性Ｆｌｏｒｙ－Ｈｕｇｇｉｎｓ理论，并提出了一种获得四元相图的方法，利用四元相图能较争地描述四元体系，利用改性的四元理论，能了地理解该种体系的液－液相分离行为。