运动三能级原子双光子冷却的理论研究

从三能级原子在双光子跃迁过程的辐射压力入手,利用其动量扩散系数和阻尼系数,以铷原子为例进行了双光子冷却的理论研究.研究结果表明:三能级原子经过双光子冷却不但可以得到较多普勒极限更低的温度,而且具有较高的冷却效率,此结果可为实验研究提供理论基础.     

电力工业的非参数效率测度分析

对资源优化配置的非参数模型在电力工业中的应用进行了研究.选择了国内部分电网的数据,从纯技术效率、规模效率以及投入可处置度、投入组合效率、投入综合效率的角度对部分电力企业的资源配置效率进行了横向分析,结果表明,不同的电力企业之间的资源配置效率差距较大,电力企业总体上生产性投资的要素组合比例不合理,利用率较低.     

空气潜孔锤钻进技术在舜皇山基岩地热深井的应用

空气潜孔锤钻进技术不仅可以提高钻探效率,而且不损害地热储层,因此在地热井中的应用十分广泛,但是仍受到钻探深度和出水量的限制。在湖南永州舜皇山基岩地热深井钻探过程中,常规牙轮钻进与泥浆钻进工艺存在钻进效率低、堵塞储层、影响出水量的可能。应用空气潜孔锤钻进技术实现了钻探深度的突破,钻探深度达到1820 m,实际出水量400 m3/d,出水温度43 ℃,符合设计指标。本文总结了相应的钻进工艺措施,以期促进对该技术在地热深井中的推广应用。     

Moving pick‐up‐type contactless power transfer systems and their efficiency using series and parallel resonant capacitors

The equivalent circuit, the efficiency, and the important characteristics of moving pick‐up type contactless power transfer systems are described. If the primary series capacitor and the secondary parallel capacitors are chosen correctly and the winding resistances are ignored, the equivalent circuit of the transformer with these capacitors becomes the same as an ideal transformer at the resonant frequency. This simple approximation helps to understand the phenomena occurring with load changes. Because the circuit analysis becomes simple, the approximate value of the power transfer efficiency can be derived. This paper describes the determination of the capacitor values, the derivation of the equivalent circuit and the efficiency, and test results. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 172(2): 47–54, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20970     

欧美小型电动机能效法规最新动态研究

欧盟和美国先后对小型电动机的能效要求出台强制性法规,分别于2009年、2010年正式实施。从主要内容和技术指标解读两项法规,重点研究欧美对于2.2kW以下的小型电动机的最低能效要求及我国相关国家标准要求的差异。在此基础上,提出应对两项法规的思路和建议。     

M701F型燃气轮机的在线运行负荷特性

分析了重型燃气轮机负荷特性的影响因素,提出了研究重型燃气轮机负荷特性的技术路线。基于此,针对某M701F型燃气轮机,以国际标准化组织(International Organization for Standardization,ISO)的标准条件为基准,由机组的在线运行数据获得其负荷特性曲线,并建立负荷特性的数学模型。考察该燃气轮机6 940组实际数据,得出结论:当折算基准功率不小于18MW时,其负荷特性数学模型的最大相对误差不超过5.73%。     

金属切削液在轴承加工中的应用

着重介绍金属切削液的分类、功能及其在轴承加工中的选用。在轴承加工中,一般有车削、铣削、钻削、铰削和磨削等多种加工工艺,其中磨削加工是一道非常重要的精密加工工序,如内圆磨削、外圆磨削、平面磨削和沟槽磨削等。轴承加工中使用的水基切削液不仅要具有冷却作用,还要有润滑、清洗和防锈的功能。重点介绍金属切削液的主要功能及其在轴承加工中的应用。     

新型钻镗刀的应用

介绍了一种新型复合刀具——ECOCUT钻镗刀,以及该刀具在数控加工中与普通刀具的综合对比情况.     

Analysis of the energy performance of a ground source heat pump system after five years of operation

GeoCool plant was the result of a EU project whose main purpose was to adapt ground coupled heat pump technology to cooling dominated areas. The execution of this experimental plant was completed at the end of year 2004, starting on February 2005 the regular operation of the air conditioning system. Since then, GeoCool facility has been monitored by a network of sensors characterizing its most relevant parameters. Several aspects of the performance and behaviour of the system during its first operational year were presented on a previous paper. This paper presents the energy performance measurements of GeoCool ground coupled heat pump system acquired during five years of operation as well as the evolution of the return water temperature from the ground as a representative of the ground temperature. The analysis of the experimental results shows that the system energy performance is maintained through the years with no appreciable impact on ground thermal response.     

Basic actions to improve energy efficiency in commercial buildings in operation

Numerous studies have focused on improving energy efficiency in commercial buildings. Engineers and researchers have developed complex methods to improve energy efficiency, but buildings are often managed by non-specialised technicians who need understandable and cost-effective actions to implement in their buildings. This paper presents basic actions on which to base improvements in energy efficiency in commercial buildings in operation. Furthermore, obtained results and details of the implementation of these techniques in various buildings in the Universitat Politècnica de València are presented.