电动机调速节电方式的选择

异步电动机是使用最广泛的动力机械,电能消耗约占总发电量的60％,降低电动机的能耗是节电工作的主要任务之一。而我国电机拖动系统消耗的电能多达全国总耗电量的2/3,所用电机90％是交流异步电动机。其中,风机、泵类拖动电机的耗电量约占总耗电量的35％     

调速节电示范项目效果显著──介绍浙江调速电机厂的电磁调速电机

调速节电示范项目效果显著──介绍浙江调速电机厂的电磁调速电机国家经贸委资源节约综合利用司我国电网总负荷中，拖动各种设备的电动机耗电量约占６０％左右。其中，拖动风机、水泵的电机耗电量占全国总用电量的３１％。这些设备中，约有５０％是变工况运行，而且绝大部...     

节能减噪风扇的应用

一、节能减噪风扇原理风扇按原理可分离心式和轴流式两种。当离心式风扇旋转时,所产生的离心力将叶片间的空气向叶轮外缘甩出去。因而,在风扇叶轮外缘出口处形成压力,气流在此发生运动方向的改变,与此同时在叶片间产生较大涡流,又因风罩形状与风扇配合不当,气流在外罩内形成局部涡流,因此,效率仅为20～30%,一般风耗约为电机容量     

新型环保宠物粪便处理系统研究

为改善宠物带来的环境污染及对人体的威胁,研究具有收集系统、生物堆肥系统的新型宠物粪便处理装置。该装置将叶轮中空气高速排出,与外界形成较高的气压差,将宠物粪便吸入电机装置进行采集,再通过好氧堆肥方式得到有机复合肥。     

WQ型机械压力式自控燃烧器

WQ型机械压力式自动控制燃烧器(以下简称WQ型燃烧器),是在吸收国外同类产品先进技术的基础上,研制开发的国产垃圾焚烧炉辅助燃烧装置,性能测试及实际应用情况表明,WQ型燃烧器具有良好的控制功能和燃烧性能,完全能够满足不同型号规格焚烧炉的辅助供热和全自动运行控制要求,可以取代同类进口产品.一、结构和工作原理1.主要结构WQ型燃烧器为机电一体化产品,由燃烧机和控制箱两大部分组成.燃烧机主要由蜗壳、电机、叶轮、齿轮泵、柴油枪、污油烧嘴、电磁阀、点火组件、风门调节组件、火焰监测组件等组成;风机叶轮、     

曝气池处理炼油污水的几点体会

一、概况我厂污水二级处理装置为表面加速曝气池4座,直径17米,总容积684.3m~3、曝气区457.7m~3由于回流缝尺寸不均匀,开工后增设了回流缝吹扫风管。曝气机为金重出产的 BQ(?)5泵型叶轮。配40瓦电磁调速电机。曝气机最大转落只能达60转/分左右。各部尺寸均未达设计要求。     

试论水泵节能运行及控制系统

随着电子信息技术的发展,电机节能的前景十分看好。据国家能源部的初步估算:如果全面启动电机节能工程,推广变频调速、永磁调速等先进电机调速技术,改善风机、泵类电机系统调节方式,逐步淘汰闸板、阀门等机械节流调节方式,全国的用电量将下降15%~20%而GDP保持不变。通过研发高效节能的变频调速技术,在工业、交通、办公自动化等领域推广使用,将电机的平均能耗下降20%~30%,这是电机行业"十一五"期间的节能目标。本文对水泵改造节能运行的理论和实践进行阐述。     

供水系统污泥泵的故障分析及改进措施

分析了中国石化扬子分公司水厂供水装置污泥泵故障的原因是由于高速含固体颗粒的水流对铸铁叶轮的磨损破坏和汽蚀与磨损的联合破坏,造成泵叶轮磨损。根据分析结果,采用耐磨的2Cr13对叶轮材质改进及表面涂覆耐磨涂层的措施,对该泵叶轮进行综合改造,运行半年后解体观察,叶轮部分无明显腐蚀,效果良好,达到了预期目的。     

建设部将加大国家机关办公建筑等节能监管力度

建设部有关人士在前日召开的中国建筑节能年度论坛上介绍，目前，国家机关办公建筑和大型公共建筑高耗能的问题日益突出。据统计，国家机关办公建筑和大型公共建筑年耗电量约占全国城镇总耗电量的22％，每平方米年耗电量是普通居民住宅的10倍～20倍，是欧洲、日本等发达国家同类建筑的15倍～2倍。     

三洋电机与清华大学共同验证“甲醛”连续去除实验成果

12月9日,为了推动室内空气净化技术的科研技术进步和工程应用,三洋电机株式会社与清华大学环境科学与工程系在北京共同举行"电解水技术最新验证成果"发布会。三洋电机为了研究室内空气净化技术,与清华大学环境科学与工程系共同建立了能够进行低浓度化学物质动态分析的"测试舱",并验证了三洋电机的电解水技术对"甲醛"的长期稳定的去除性能,     

离心压气机增效扩稳技术研究及高海拔应用

目的为提高离心压气机高海拔气动性能提供新的研究方法。方法分析叶片弯/掠造型及机匣处理两种压气机增效扩稳的技术及机理,并采用数值模拟的方法对比分析了海拔5500 m条件下原型叶轮及采用叶片前掠叶轮的气动性能。结果相比于原型叶轮,采用前掠叶型的压比最多可提高3.09%,效率可提高0.71%,叶轮流道内流动损失减小,叶轮高海拔气动性能得到了提升。结论对低雷诺数下离心压气机机匣处理结构的应用有一定的指导作用。     

线路板粉末风选过程气固两相流模拟及实验

针对线路板破碎粉末的特点,提出了一种通过风力分选实现废旧线路板中金属和非金属分离的方法.分别采用RNG k-ε模型、颗粒轨道模型模拟气流场和固体颗粒,模拟结果显示风选器腔体处于旋风状态,风压随着风选器半径和高度的增加而升高,至风选器高度为1.2m附近达到峰值.开展线路板粉末风选实验,通过模拟分析和实验分别得到不同粒径、不同叶轮转速下的优化工艺参数,结果表明粒级对实验结果的影响最大,当线路板粉末粒径为0.125~0.212mm、叶轮转速为200r/min时,金属回收率最高达到96.5%.最后进行分选效果的实验-模拟对比分析,验证了模拟的有效性及分选方案的可行性.     

Dimensional analysis and scaling in mechanical mixing for fabrication of metal matrix nanocomposites

For a successful enhancement of mechanical properties of metal matrix nanocomposites, a homogeneous nanoparticle dispersion and distribution in the solidified metal is required. Mechanical mixing can be used for initial break-up of agglomerates, and its study can be simplified with dimensional analysis. Using this technique, mixing time and vortex height were assessed while varying fluid properties, impeller angle, and angular speed. Three relevant dimensionless numbers were recognized: the Reynolds (Re), Froude and Galilei (Ga) numbers. Based on blade and impeller shaft angles, a modified Froude number (Fr*) was defined. These parameters were calculated experimentally, varying angular speed from 200 to 1000 rpm for three different impeller angles: 0°, 15° and 30°. This procedure was performed with three fluids: water, and two aqueous glycerin solutions (25% and 50% by volume). Digital images were taken and processed to measure vortex height. Mixing time was measured for water at 0° impeller angle, angular speed ranging from 200 to 1200 rpm. Results showed an optimal dimensionless mixing time with respect to Re. A linear relationship was found between dimensionless vortex height and Fr*. The first had a second order polynomial relationship with the product ReFr*, regardless of impeller angle. This relationship, together with the Ga, specific for each fluid, allows scaling the results to other fluids such as molten pure aluminum. This study allows experimenting in simpler systems that involve transparent fluids, room temperature and low cost, to then elaborate a prediction of vortex height in fluids where measurements are difficult and costly, such as molten metals.     

Prediction of vortex height from mechanical mixing in metal matrix nanocomposite processing by means of dimensional analysis and scaling

Mechanical mixing can be used for initial dispersion and distribution of nanoparticle agglomerates in metal matrix nanocomposite (MMNC) fabrication. As vortex height increases, flow is enhanced as well as the risk of oxidate melt contamination. The goal of this study was to examine and predict vortex height using dimensional analysis while varying fluid and the angular speed of a pitched square-blade impeller. An equation proposed by Markopoulos et al. was verified for the present experimental conditions. The relevant dimensionless numbers were the Reynolds (Re), Froude (Fr) and Galilei (Ga) numbers. A modified Fr was defined (Fr*) including the shaft and blade angles of the impeller. Experiments allowed calculation of the dimensionless numbers. Two fluids, water and 50 vol% aqueous glycerine, were used. Angular clockwise speed varied from 200 to 900 rpm in 100 rpm increments. Vortex height was measured in lateral view digital images. Correlations of the dimensionless numbers yielded, first, a linear relationship of the product of dimensionless vortex height (H) and specific gravity (ρ*) with respect to Fr*. A polynomial relationship was found between H and ReFr* for each fluid. The polynomial coefficients, in turn, follow a power law behavior with respect to Ga. This allows a prediction of vortex height in other Newtonian fluids that satisfy the single-phase isothermal flow condition. Perhaps, molten aluminum used in MMNC fabrication, can be analyzed based on a simple, room temperature, low cost transparent fluid system. For the experimental conditions in this study, the equation proposed by Markopoulos et al. was valid. The predicting methodology was verified with experimental results using 25 vol% aqueous glycerine, resulting in an absolute percent error of 5.29%, comparable and lower than an error of 9.12% obtained by predicting vortex height with Markopoulos’ equation.     

气喷旋冲烟气脱硫装置运行关键控制

气喷旋冲湿式石灰石-石膏法烧结烟气脱硫装置(XPB)是宝钢针对烧结烟气特性自主研发的新型脱硫技术,较详细论述该系统稳定、经济运行的关键控制:增压风机风门或叶轮的控制、吸收塔进气箱温度的控制、吸收塔反应池pH值的控制、曝气管浸没深度的控制等。     

高浓度臭氧水溶液研究

采用涡流叶轮泵、射流器和喷嘴等物理方法可将高浓度臭氧气体（＞100g/m³）有效地溶解于水,使臭氧溶解率达到98.6％,臭氧水溶液的臭氧浓度达到8.06g/m³,生成无残留物的绿色强氧化药剂、强消毒杀菌剂．     

不同曝气工艺对佛山水道水质DO和COD的影响

通过现场模拟试验,探讨了雾化管、射流器、橡胶坝和叶轮4种曝气工艺对改善佛山水道水质的影响。结果表明,4种工艺的平均复氧效率(14.3%~36.6%)和对COD的平均去除率(9.6%~24.6%)显示了较大差异。橡胶坝和雾化管曝气工艺的复氧效率较高,而叶轮和射流器曝气工艺则对COD去除有较好效果。在曝气并结合混凝的对照试验中,投加絮凝剂有助于提高水中DO和去除COD。     

基于ELM网络的污水处理COD值预报模型研究

通过对沈阳某污水处理厂的叶轮气浮法污水工艺进行研究分析,得知其过程具有多变量、非线性和时变等特性,这些特性对于处理后水质的COD值准确检测非常重要。COD值的在线检测设备通常有一定滞后,影响了现场对水质的控制和提高,为此采用ELM网络来建立COD值的预报模型,并通过MATLAB软件进行了仿真研究,仿真结果表明该模型具有较好的预报效果。