愿变频调速器早日实现国产化

愿变频调速器早日实现国产化中国石化北京设计院董长善变频调速技术以其在节电方面的显著效果在国内外得到普遍应用，国外许多大公司纷纷跻身于中国市场，并取得了很高的经济效益，而国产变频调速器在国内却迟迟推广不开，原因是多方面的。１．变频调速新潮流变频调速可用...     

吸送风机变频节能改造

介绍华能陕西秦岭发电有限公司吸送风机变频改造方案及节能效果，分析风机变频运行中存在的问题以及解决的办法：实践证明，应用变频技术可降低机组厂用电消耗，节能效益显著。     

流体负载电机的变频调速

本文阐述了流体负载电机变频调速的必要性，从电机学的角度简单分析了电动机交流变频调速时电磁转矩的变化飞速，说明了交流变频调速在流体国电机上应用的可行性，并从民能的角度进行了水泵我载电机变频调速的经济效益分析，表明变频调速在流体负载电机上的应用确定可行。     

变频空调器的节电机理和实效

本文叙述了变频空调器通过变频调速、实现节能省电的机理，并借助于一则普通空调器与变频空调器用电量大小比较的具体实例，从量的角度简明扼要地阐述了变频节电的实际效果。     

选用变频调速器应注意的几个问题

使用变频调速器的目的是方便操作，减少故障与节能，但在实际应用中，其侧重点是不同的。文中分析了变频调速器作各种特殊用途时的使用特点，总结出确定变频调速器容量的几种方法，并阐述了与电机最佳匹配的原则     

深井直接供水变频调速控制系统的探讨

本文在对深井直接供水系统压力变化分析的基础上，说明了该系统变频调速控制的必要性，阐述了变频调速供水原理，并提出了深井直接供水变频调速控制的效益分析。     

鼓风机变频调速技术与节能

介绍了煤气鼓风机变频调速技术的原理和特点，通过煤气鼓风机变频调速技术改造的实践和鼓风机几种节流调节方式的对比，说明了变频调速技术的节能特性及效果，减少操作强度，节能效果显著。     

变频调速技术在805#炉引风机上的应用

介绍变频调速器在引风机上的具体应用。给出了变频调速在燃油锅炉燃烧控制过程中的应用实例。引风机通过使用变频调速技术，实现了锅炉的优化控制，达到运行稳定，节约能源，提高经济效益的目的。     

变频调速对电动机损耗及效率的影响

本文通过对变频调速原理的分析，引出变频、降压运行时电动机损耗的计算公式，从而计算出更为准确的电动机运行效率．     

工业变频自动控制系统的工程应用

工业变频自动控制系统的工程应用中日合资华森测控技术有限公司童楚生１问题的提出电动机的调速经历了直流调速、变极调速、交流变频调速等艰苦的发展历程，在交流变频调速工程应用上，许多尚处于单机应用手动控制的简单使用阶段，未曾使变频及整个系统设备投入最佳运行状...     

Unerroric of control of mutual compliance of the efficiency of hydrogen engines of unmanned vehicles in the conditions of mass production

The issues related to the reliability of hydrogen engines of unmanned vehicles and increasing the efficiency of using hydrogen as fuel when using the method of its production during the decomposition of hydrogen-containing molecules of liquid-phase organic compounds in a plasma discharge under the action of intense ultrasonic exposure are considered. Experiments have shown that as a result of decomposition in the acoustoplasma discharge of liquid hydrocarbons, solid-phase carbon-containing products are formed, chemical transformations occur in the liquid phase and hydrogen-containing combustible gas is formed. Hydrogen-containing gas can be used as fuel immediately after synthesis, i.e. it does not require separation, since in addition to hydrogen it contains only impurities of CO₂ and water vapor. The purpose of the study is to formalize the basic conditions for tightening the control of mutual compliance with the efficiency of hydrogen engines of the same series in the conditions of their mass production. Methods of mathematical statistics and hardware-software modeling were used in the study. The term “unerroric of quality mutual compliance control” is introduced to describe a set of hardware and software tools for such control. The principle of in-depth testing of the technical condition of such engines of one series is described in a multidimensional formulation of the quality control problem for three of their operating parameters at once. The conditions for increasing the mutual correspondence of the measured values of such parameters in the conditions of serial production of hydrogen engines are formalized.     

小型锅炉烟尘测试时锅炉出力的计算

锅炉烟尘测试时,必须对锅炉出力进行测试。但监测中,许多小型锅炉往往不具备相关的计量装置和仪表,为解决这一问题,文章提出了用烟气量和空气过剩系数来计算锅炉的出力的公式,在实际使用中,该方法简单易行,其结果和实测值具有很好的一致怀。     

中国煤炭地下气化技术的发展

本文综述了煤炭地下汽化技术的国内外发展现状,对我国“长通道、大断面”煤炭地下气化新工艺给予了技术经济评述,并提出了发展煤炭地下汽化技术的政策建议。     

Review of theory of distortion and disintegration of liquid streams

Linear and nonlinear analyses of the instabilities and distortion of liquid streams injected into a gaseous media are discussed. The various fundamental mechanisms and the predictive capabilities for the distortions are emphasized. Round jets, planar sheets, annular sheets, and conical sheets are discussed in detail. The balance between capillary and inertial forces is primarily examined. The method for simplifying the analyses in the case of thin liquid sheets is discussed. The capabilities for representing the droplet size distribution that follows the stream disintegration are outlined.     

MgO膨胀剂细度对MgO水化和水泥浆体膨胀的影响

基于《水工混凝土掺用氧化镁技术规范》中的Ⅰ型氧化镁（MgO）,研究了该型MgO膨胀剂（MEA）细度对掺粉煤灰水泥浆体膨胀性能的影响。即采用X射线衍射分析(XRD)及同步热分析（TG DSC）分析了掺MEA水泥浆体中MgO的水化性。结果表明,养护温度相同时,MEA的细度对水泥浆体内MEA中MgO的水化和水泥浆体的膨胀无显著影响,产生的膨胀均能补偿水泥浆体的收缩;MEA的细度可从试验设计采用的45 μm筛筛余15%左右增加到30%左右,这将有利于MEA生产企业的节能降耗。     

机车车轮多轴疲劳强度安全评定的研究

使用ANSYS8.0软件对高速列车车轮进行了三维有限元分析,计算出车轮在直线、曲线和道岔条件下牵引、制动共6种工况时孔边薄弱部位的应力,分别通过Mises等效平均应力方法、Sines平均主应力方法和应力分量中考虑平均应力方法计算出应力在极值位置时的等效应力幅、等效平均应力,从而进一步算出车轮的安全系数,对其疲劳强度进行评定,并对3种方法进行了比较研究。     

Constructal optimization of the geometry of an array of micro-channels

This paper documents the geometric optimization of an array of circular and non-circular ducts. The optimization was carried out numerically using finite volume method. As optimal dimensions were independent of the array configuration, the numerical simulation was performed on a unit cell. Numerical optimization for circular, square and isosceles right triangle cross-sections of channels was performed. Based on the results of this investigation, some correlations were proposed to predict the optimal hydraulic diameter and dimensionless heat transfer per unit volume. In addition to examining the effect of pressure drop on these parameters, it was showed that among the different geometries of this study, square cross-section has the most efficiency for a given volume. The numerical results of the present study were compared with approximate results reported in the literature which a good agreement was observed.     

Heat of vaporization of mixtures

General expressions for the heat of vaporization of mixtures at constant pressure; at constant temperature; and at constant pressure, temperature, and composition are proposed. The last one is related to the liquid-vapor interface where steady vaporization or condensation is taking place. Numerical examples by the proposed expressions are shown for binary mixtures of HCFC22(R22) and (HCFC123(R123) © 1997 Scripta Technica, Inc. Heat Trans Jpn Res, 25(1): 12–24, 1996     

固体热辐射Yong性能分析

本文对漫灰均温物体在常物性条件下对外辐射传热的Ｙｏｎｇ值计算建立了数学模型。通过与物体内能Ｙｏｎｇ公式的数值计算比较,得出了辐射能量的Ｙｏｎｇ值不大于内能Ｙｏｎｇ值的结论。从初步的热射Ｙｏｎｇ值计算公式发现。Ｙｏｎｇ与物体表面辐射率有关。     

Measurements of concentration distribution of hydrogen jet using deflection of center of the laser spot

The main purpose of this work is to propose a new method to evaluate the concentration distribution of the hydrogen jet by using a He–Ne laser through the jet. This research attempts to apply the expression of concentration Gaussian distribution, the refraction formula of inhomogeneous refractive index medium, and the concentration inversion function to disclose the displacement of the center of the laser spot at different heights in the gas jet. The spot images of the laser beam passing through the gas jet at three vertical heights z = 10d, 20d, 30d, and different radial positions are obtained. The radial spatial asymmetry of the gas jet is also found in the experiment. Finally, the calculated concentration distribution curve and the fluent simulation curve, it is found that the two results are very similar. Our findings show that the error between the concentration distribution of this method and the simulated concentration distribution reaches 2.43%.