水轮发电机带暖风窗结构通风系统分析

发电机放热风用于电厂厂房采暖是一种经济节能的方法。为了分析增设暖风窗的合理结构及对发电机组通风冷却系统的影响,本文采用网络分析法对发电机组通风冷却系统进行了计算分析。结果表明发电机上加装暖风窗放热风是可行的,对发电机冷却无不利影响。     

船舶柴油发电机组的设置和安装

本文对柴油发电机组的设计、安装中几个常见的问题如柴油发电机机组选择、容量选择、通风冷却系统、储供油系统、及排烟消音系统在设计和安装中应注意和遵循的原则进行了阐述。     

大型汽轮发电机通风系统研究综述

为满足汽轮发电机不断地向大型化发展地需要，必须对大型汽轮发电机的通风系统进行优化设计，以提高其通风冷却效果。为此，国内外对影响汽轮发电机通风冷却状况的主要因素如冷却介质的流动与传热特性、不同通风系统的通风计算方法、通风系统的结构等进行了一系列理论分析和试验研究，并取得不少具有实际应用价值的成果。在对现有成果的分析和总结的基础上，指出了有待进一步研究之处。     

基于Kuli的某乘用车变速箱冷却系统仿真分析

本文利用流体仿真软件Kuli建立了基于试验参数的某乘用车变速箱冷却系统模型,对该变速箱冷却系统进行了仿真计算,并与试验结果比较,结果显示:变速箱侧扁管数目仿真结果与试验值误差为8.3%;油冷器冷却液流量仿真值与试验值误差为1.5%。这表明:仿真结果与试验数值吻合较好,仿真模型可靠,为乘用车变速箱冷却系统的设计与匹配提供理论依据,并且,通过Kuli软件仿真可以较大提高冷却系统的分析效率,缩短研发周期,节省试验费用。     

发动机冷却系统陈述式动态模型

鉴于发动机冷却系统传统过程式模型在模块化、重用性、参数化等方面的不足,在详细分析发动机冷却系统部件数学模型的基础上,采用面向对象的陈述式建模方式在多领域仿真平台MWorks上建立了易于管理、修改、重用和扩充的发动机冷却系统陈述式动态模型库,模型库各重要部件均采用动态表征。为更精确地计算散热器动态性能,提出了二维离散方法构建散热器模型。通过试验数据验证了散热器模型,散热器出口冷却液温度和空气温度的稳态仿真值与试验值误差分别为4.20%和4.75%。通过调用模型库中的部件模型构建了结构典型的发动机冷却系统,并对仿真结果进行了理论对比分析。     

汽轮发电机转子风斗流动特性的实验研究

在转子气隙取气通风系统中,风斗的取风与引风性能直接影响系统的通风冷却效果.对汽轮发电机转子气隙取气斜流通风系统进行了静态实验模拟,研究了结构参数和结构型式对转子进、出风斗取风性能和引风性能的影响规律,为汽轮发电机转子风斗的优化设计提供了可靠依据.     

1000MW汽轮发电机气隙流场的数值模拟

针对1 000MW系列水氢氢汽轮发电机,对发电机的气隙进行2D建模,对气隙及径向风道采用RNG k-ε湍流模型应用多重坐标系进行数值模拟,对发电机的气隙流场进行分析,并用模拟所得数据计算转子同一风道不同匝线棒中的气体流量得出流量分布规律,发现各线棒中气体流量较为均匀,为发电机的通风系统的设计提供依据.     

大型蒸发冷却发电机定子绕组绝缘电阻测试及分析

本文结合发电机定子绕组蒸发冷却系统组成,提出了不接屏蔽端和接屏蔽端两种测量发电机定子绕组绝缘电阻测量方法,并对定子绕组绝缘电阻测量值偏低进行分析处理,通过不同测试条件下的对比试验,发电机定子绕组在充液状态时,采用接屏蔽端方式能够准确测量定子绕组绝缘电阻。     

汽轮发电机转子风斗流动特性的实验研究

在抟子气隙取气通风系统中，风斗的取风与引风性能直接影响系统的通风冷却效果。对汽轮发电机转子气隙取气斜流通风系统进行了静态实验模拟，研究了结构参数和结构型式对转子进、出风斗取风性能和引风性能的影响规律，为汽轮发电机转子风斗的优化设计提供可靠的依据。     

大功率风力发电机冷却系统的试验研究及数值模拟

冷却系统是风力发电系统的重要组成部分,其性能的优劣是衡量发电机能否安全可靠运行的重要因素。文章针对某型3 MW风力发电机的冷却问题,搭建了风力发电机试验台,研究了100%负载条件下冷却系统的性能表现,并采用数值模拟方法对其进行分析,提出了4种优化方案:1增大乙二醇流量;2降低乙二醇进口温度;3增大空气流量;4采用空心导线冷却方式。试验和模拟结果表明:电机在100%负载条件下温度高于电机所要求的工作范围,需要对冷却系统进行优化;空心导线冷却方式能对电机高温区域进行集中冷却,使温升符合电机工作要求,是冷却系统的最佳优化方案。文章的研究方法和研究结果可为我国风力发电机冷却系统的相关研究提供试验和理论参考。     

大型水氢氢汽轮发电机通风系统特点及性能分析

目前功率在600 MW及以上的大型汽轮发电机多采用水氢氢冷却方式,即定子线圈采用水冷,定子铁芯及转子线圈采用氢冷.通过将采用不同通风型式的定子铁芯及转子线圈进行组合,可派生出多种通风系统,但是不同通风系统之间的性能尚无法用统一的数学模型进行量化.在对水氢氢汽轮发电机不同通风系统进行分析、比较的基础上,提出了通风系统效率(EVS)的概念,并给出相应的计算方法,可对不同通风系统的性能进行比较,也可为通风系统的选择提供一定的参考依据.     

Design features of the Bad Creek pumped storage project generatorsmotors

The four pumped-storage generator/motors for the Bad Creek project in Oconee County, SC, are distributed. Consideration is given to the general unit construction, the cooling system, the thrust bearing, and the structural design. The most unique design aspect of these units is the arrangement of the forced fan ventilation system, which uses twenty motor-driven fans to direct air in very controlled paths. The adequacy of the system was verified by prototype laboratory testing. Field testing is planned to verify the system and machine efficiencies at the time of unit startup     

瓦斯发电机房通风降温问题研究

叙述了针对瓦斯发电机房隔声与通风降温之间产生的矛盾,对通风量计算的依据、过程以及各种通风降温方式的比较结果。     

一种新型永磁磁力耦合器导风散热片的仿真研究

本研究针对一款新型永磁磁力耦合器导风散热装置的导风散热片进行仿真分析。首先设计单因素实验,对其部分几何参数进行研究,利用Fluent软件进行流固耦合模拟,得出几何参数对最高温升及阻力距的影响关系,为正交实验提供合理的参数范围。然后设计正交实验,利用极差分析得出合理的参数组合。最后利用上文参数组合建模,模拟安装不同导风散热片个数的散热效果,寻找合适个数。并与未安装导风散热片的模型进行对比,得出此新型导风散热片设计合理,具有一定的实用价值。     

Overall and zonal energy end use in an energy conscious office building

An office building of unusual design has been monitored for more than three years. Numerous submeters allow tracking of energy end use. The building was designed to make significant use of daylighting, with some passive solar heating, and an emphasis on night ventilation cooling of thermal mass. The overall building end usages are compared to those of three zones of varying orientation, spatial character, size, and population. Insights about daylight-sensing controls of indirect electric lighting, “task heating,” and night ventilation of mass and air quality are presented.     

非轴带风机冷却系统在厢式柴油发电机组中的应用

介绍了某500kW厢式柴油发电机组非轴带风冷冷却系统设计特点,从节省空间、易于布置、节能和方便维修等方面出发,合理地采用了多风机并联冷却系统;介绍了其结构特点及主要设计计算过程。台架试验验证:该风机冷却系统达到预期设计要求。     

Assessing the natural ventilation cooling potential of office buildings in different climate zones in China

This paper presents an investigation of the natural ventilation cooling potential (NVCP) of office buildings in the five generally recognised climate zones in China using the Thermal Resistance Ventilation (TRV) model, which is a simplified, coupled, thermal and airflow model. The acceptable operative temperature for naturally conditioned space supplied by the ASHARE Standard 55-2004 has been used for the comfort temperature setting. Dynamic simulations for a typical office room in the five representative cities, which are Harbin, Beijing, Shanghai, Kunming and Guangzhou, have been carried out. The study demonstrates that the NVCP depends on the multiple impacts of climate, the building's thermal characteristics, internal gains, ventilation profiles and regimes. The work shows how the simplified method can be used to generate detailed, indoor, operative temperature data based on the various building conditions and control profiles which are used to investigate the NVCP at the strategic design stage. The simulation results presented in this paper can be used as a reference guideline for natural ventilation design in China.     

A review for the applications of solar chimneys in buildings

As a simple and practical bioclimatic design methodology, solar chimneys are receiving considerable attention for reducing heat gain and inducing natural cooling or heating in both commercial and residential buildings because of their potential benefits in terms of operational cost, energy requirement and carbon dioxide emission. In practical civil buildings, solar chimneys can be installed on the walls and roofs. For the purpose of improving natural ventilation performance and achieving better indoor thermal comfort, solar chimneys are always applied in the form of integrated configurations. Solar chimneys can also be used to combine with natural cooling systems so as to enhance the cooling effect inside buildings. Besides, active solar systems may be utilized to enhance the ventilation performance of solar chimneys. In this paper, the main configurations and the integrated renewable energy systems based on solar chimneys were summarized. Then the suggestions were given. Generally, solar chimney technology has been regarded as an effective and economical design method in low carbon buildings. As for the integrated energy systems based upon solar chimneys, it is still necessary to carry out more experimental investigations to acquire objective data for the system design. Besides, it is suggested to further study the optimization and control strategy of such integrated systems in different climates.