750 kV兰银输变电工程系统调试相关问题研究

750kv兰州东—银川东输变电工程是我国继示范工程之后的第2个750kV工程,输电线路长,国产高压设备多。介绍了该工程系统调试的主要内容和结论。针对调试过程中出现的问题进行了分析,并提出了建议。该工程的系统调试达到了预期目的,也为后续750kV工程系统调试积累了宝贵经验。     

舟山大陆引水工程梯级泵站集控系统设计

介绍了舟山大陆引水工程概况,分析了目前工程运行存在的问题。针对工程运行特点,设计了舟山大陆引水工程梯级泵站集控系统,提出了系统的网络架构、主要设备配置及软件设计,为实现梯级泵站集中控制和统一调度、保障工程运行安全、减少现场人员的劳动强度提供了技术基础。     

客户配电网工程投资决策分析

配电网工程的综合造价和运营费用对投资决策影响重大。搭建了配电网工程模型,阐述了配电网工程综合造价和运营费用构成,并通过比对配电网工程投资和运营费用,得到经济效益最优的客户配电网工程投资方案。实例结果表明,在享受电价优惠政策的条件下,客户自建配电网工程可取得一定的经济效益,但客户配电网工程投资最优方案随工程的综合造价和运营费用变化而变化。     

南水北调丹江口大坝加高工程施工技术

丹江口大坝加高工程是南水北调中线工程关键性、控制性、标志性的龙头工程．也是国内大坝加高改造项目中规模和难度最大的工程。本文慨要论述了丹江口大坝加高工程中的施工技术难题和解决措施,为老化和病害水工混凝土建筑物的修复和改造提供了可借鉴的经验。     

智能建筑工程的主要监理工作

智能建筑工程监理是一种专业化的、全过程的工程监理。这里针对智能建筑工程监理存在的问题,提出了智能建筑工程监理工作的主要任务与实施要点。     

无线网桥在长距离引水工程中的应用

针对长距离引水工程通信网络的构成特点,阐述了无线网桥构建长距离引水工程无线通信网络的技术要点和优势。结合大伙房引水工程中无线网桥的应用实例,介绍了无线网桥在长距离引水工程无线通信网络构建过程中的设计、安装、调试方法。     

基于外部性收益的畜禽养殖场沼气工程补贴模式分析

以我国北方某沼气工程为例,按照业主自筹全部资金、2009年国家建设补贴标准和工程实际投资3种建设投资方式,对其现有经济性进行了分析,并提出了以外部性收益为依据对沼气工程进行补贴的两种模式。结果表明,外部性收益与沼气工程运行效果和沼气产量有直接关系,依据外部性收益对沼气工程进行补贴,可以显著提高沼气工程的经济效益,推动规模化养殖场沼气工程正常运行和发展。综合沼气工程投资者和社会利益考虑,业主自筹全部建设资金,按照工程实际运行的外部性收益给予补贴,既可保障工程的正常运营,又符合整体经济性。     

论太阳能与车库型干法沼气工程的完美结合

结合传统太阳能热利用工程与德国车库型干法沼气工程,设计出利用太阳能为沼气工程增温的太阳能沼气系统,并以高寒地区哈尔滨为例,对系统进行了初步估算。结果表明,车库型干法沼气工程适合与太阳能热利用工程实现一体化,结合太阳能热利用工程后该系统年可节约标煤159.6t,同时为系统的稳定运行提供了能源保障。     

高喷灌浆技术在尼那水电站二期围堰工程中的应用

黄河尼那二期下游围堰及部分上游围堰采用高喷灌浆技术,成功地在夹河卵砾石中构筑了二期围堰防渗工程。在分析场地水文地质与工程地质条件的基础上,研究了围堰防渗工程的结构形式与工程布置,探讨了施工工艺和质量控制问题。     

能源环保型沼气工程在规模猪场排泄物治理中的应用

主要介绍了畜禽养殖场排泄物治理模式——能源环保型沼气工程在义乌某大型生猪养殖公司排泄物治理中的应用,详细介绍了该养殖场中的沼气工程的工艺路线、处理能力、工程规模、沼气发电以及工程调试运行情况。     

Experimental investigation of new designs of wind towers

Two new designs of wind towers were tested side by side with a conventional wind tower in the city of Yazd, Iran. All the towers were of identical dimensions. The two new designs were one with wetted column, consisting of wetted curtains hung in the tower column, and the other one with wetted surfaces, consisting of wetted evaporative cooling pads mounted at its entrance. The air temperature leaving the wind towers with evaporative cooling provisions were much lower than the air temperature leaving the conventional design, and its relative humidity much higher. The air-flow rate was reduced slightly in these new towers. It was found that the wind tower with wetted column performs better with high wind speeds whereas the tower with wetted surfaces performs better with low wind speeds. It is recommended that these new designs of wind towers should be manufactured in different sizes and incorporated in the designs of new buildings. They can replace the evaporative coolers currently employed in Iran, and other hot arid regions, with considerable saving in electrical energy consumption.     

汽车排放物中NOx、HC和CO的预测模型研究

为更深入细致的研究汽车有害排放物的排放规律,提出了用以计算机仿真计算的柴油机排放物的数学模型。该预测模型是以现象学燃烧模型为基础的,NOx的数学模型用广义Zeldoich不平衡原理建立,HC和CO的数学模型采用化学平衡和反应动力学原理建立。用该模型计算了某型号柴油机的排放物,得到了这3种排放物在缸内的生成过程,并从它们的生成机理出发,分析了不同喷油定时对排放规律的影响,讨论了推迟喷油措施对降低排放物的效果。实机实验结果表明计算值与测量值吻合较好,并且都反映出相同的规律:NOx和CO的生成量随喷油提前角的增大而增大,而HC排放量随喷油提前角的增大而减少。     

不同扩散效应下一维湍流模拟氢气-空气射流的扩散火焰

应用一维湍流模型（ODT）来研究湍流射流氢气．空气扩散火焰，研究过程中采用详细化学反应机理和多分量输运属性．对于火焰长度、主要燃烧产物及温度的预测较好地符合了实验结果．ODT模拟结果产生了较高的近场扰动．提出了一种旨在通过修改涡事件选择过程从而提高ODT模型精度的新观点．在模拟中检验了微分扩散效应，结果显示当前火焰中存在着显著不同的扩散效应．     

二甲基醚喷雾数值模拟与实验研究

基于KIVA程序对二甲基醚(DME)的喷雾特性进行了三维数值模拟,利用高速摄影机在定容室内对喷雾过程进行了深入的实验研究．分析了环境背压、启喷压力、喷孔直径等因素对喷雾特性的影响．比较和分析了喷雾特性的模拟结果和实验数据,并将二甲基醚的喷雾特性与柴油进行对比．通过研究,获得了DME喷雾锥角、贯穿距和索特平均半径随喷射、环境条件变化的一般规律．     

核电厂汽轮机热力系统分析与评审

在核电项目汽轮机评标过程中,发现供货商因忙中出错或因商业利益,提供的热力系统方案会存在参数选择不合理、计算方法不正确等问题.通过推导有疏水或纯疏水级段蒸汽焓值计算方法,采用比焓降更精确、更真实反映机组性能的功率作为效率计算基准,提出理想功率、当量流量和理想焓降三个性能指标,对供货商提供的热力系统方案进行分析与评审,及时发现和纠正了各种错误,合理维护了业主利益.并对在运行核电机组热力系统作计算与分析,提出了机组存在的问题和改进方案.     

Characterisation of oils from the fluidised bed pyrolysis of biomass with zeolite catalyst upgrading

Biomass in the form of pine wood was pyrolysed in an externally heated 7.5 cm diameter, 100 cm high fluidised bed pyrolysis reactor with nitrogen as the fluidising gas. A section of the freeboard of the reactor was packed with zeolite ZSM-5 catalyst. The pyrolysis oils before and after catalysis were collected in a series of condensers and cold traps. In addition, gases were analysed off-line by packed column gas chromatography. The compositions of the oils and gases were determined in relation to the primary fluidised bed and after catalysis at increasing catalyst bed temperatures from 400° to 550°C. The oils were analysed by a number of techniques to determine composition, including liquid chromatography, gas chromatography/mass spectrometry. Fourier transform infrared spectroscopy and size exclusion chromatography. The results showed that the oils before catalysis were highly oxygenated; after catalysis the oils were markedly reduced in oxygenated species with an increase in aromatic and polycyclic aromatic species.

The gases evolved from the fluidised bed pyrolysis of biomass were CO₂, CO, H₂, CH₄, C₂H₄, C₃H₆ and minor concentrations of other hydrocarbon gases. After catalysis the concentrations of CO₂ and CO were increased. The conversion of oxygenated compounds was mainly to H₂O at lower catalyst temperatures and CO₂ and CO at high catalyst temperatures. Detailed analysis of the oils showed that there were high concentrations of biologically active polycyclic aromatic species in the catalysed oil which increased with increasing catalyst temperature. The oxygenated compounds in the uncatalysed oil were mainly phenols and carboxylic acids. After catalysis these decreased in concentration with increasing catalyst temperature     

煤中钾存在形式研究

煤中钾的存在形式与煤的灰污性质密切相关。通过萃取的方法,分别以水、醋酸铵和稀盐酸为萃取液对钾在我国一些煤中的存在形式进行了研究。结果显示,煤中钾除了以硅铝酸盐形式存在外,还有其它多种存在形式,尤其在低阶煤中,其它形式的钾占有显著份额。钾在煤中存在形式与煤种、煤阶、煤的显微组分和煤粒径有关。     

发动机缸体主轴承座及主轴承盖的动态应力和温度测量

为评估某直列6缸柴油机缸体有限元强度分析结果,采用应变电测法实测了该发动机缸体上可能的危险部位主轴承座、主轴承盖动态应力以及这些部位的温度。在缸体上布置了5个测点,对各贴片处进行了专门加工;选用了中温应变片及应变胶,并对各贴片进行了加温固化和耐油处理。实测中应变补偿片只能置于室温环境,之后根据所测温度考虑了应变片热输出,从而得出各测点动态应力结果。试验结果表明,该测量方案可用于测量发动机缸体、缸盖等中高温零部件的动态应力和温度。     

Comparison study of fuel characteristics of slow pyrolyzed chars with Neyveli lignite

As coals are fast depleting, suitable means of substituting coal need to be explored. In this work, a feasibility study of co-firing lignite with char was investigated. Some locally abundant biomass were slow pyrolyzed. The pyrolyzed chars were characterized and their fuel properties were compared with that of Neyveli lignite. The study indicated that the heating value of chars (except rice husk char) were higher than Neyveli lignite. The study also revealed that the properties of chars were on superior to Neyveli lignite and can be substituted to Neyveli lignite.