某工程实施地源热泵系统的可行性研究

以某工程为例,对其全年吸放热不平衡率进行分析,并通过对两测试井进行夏季工况条件下的地埋管换热性能实验,得出夏季单位井深换热量为 108.5W/m,理论分析冬季单位井深换热量为57.1W/m,最后与常规空调系统进行经济性比较,最终论证该工程实施地源热泵方案的可行性。     

某办公建筑地源热泵系统冬季运行工况测试与分析

以山东省东营市某办公建筑地源热泵空调系统为研究对象,对其冬季运行工况进行测试,分析地源侧供水温度及制热性能系数随负荷率的变化情况,得到系统性能系数COP为3.0,机组COP为4.1。测试数据表明,该工程地温恢复状况良好,未出现"热堆积"现象,系统运行工况稳定。     

邯郸地区某空气源热泵供暖系统运行性能分析

为提高空气源热泵供热系统的实际运行性能,在2019—2020 年供暖季对邯郸地区某老旧小区空气源热泵供热系统进行了现场测试,根据室外空气温湿度、系统供回水温度及流量、耗电量的实测数据和变水温运行调节方式,对系统长期运行性能进行了分析,对比了4 种工况条件下的系统运行特性。测试分析结果表明：对于整个供暖期的能耗而言,分阶段变水温调节有利于促进空气源热泵节能运行。邯郸地区冬季室外相对湿度较高,容易导致空气源热泵运行效果不佳、供热量不足。此时在分阶段变水温调节的基础上采用分时段变水温调节,有利于改善系统运行效果,供暖期第Ⅱ阶段的COP′由1.63提高至第Ⅲ阶段的1.76,提高了8%。     

新型蒸发冷却空调系统在数据中心的运行测试分析

针对数据中心空调系统全年不间断供冷、运行能耗高的特点,提出一种由蒸发冷却冷水机组作为全年主导冷源,并结合乙二醇自由冷技术的数据中心用新型蒸发冷却空调系统,充分利用室外环境干空气能与冬季自然冷源,实现干燥地区数据中心全年完全自然冷却。本研究的目的在于,介绍新系统的工作原理,分析系统运行中蒸发冷却冷水机组运行参数以及新型蒸发冷却空调输配系统在数据中心运行过程中参数变化规律,并讨论其节能性,为数据中心冷却工作提供新思路。以新系统实际应用工程——乌鲁木齐某数据中心(冷负荷为2760kW)为研究对象,选取最热月的典型日,通过对系统进行逐时运行参数的实际测试,得出空调系统各换热环节热量传递过程的温度、热量变化规律。在乌鲁木齐夏季最热时,蒸发冷却冷水机组全天出水温度范围在13.1～16.9℃,平均值为14.9℃,新型蒸发冷却空调系统COP值为6.65kW/kW,相比传统机房制冷系统节能率超过60%。     

空气源热泵辅助吸收式地源热泵系统的适用性分析

针对严寒地区集中供热系统能源利用效率低的问题,结合该地区应用地源热泵系统存在土壤吸/排热不平衡的问题,本文提出将一次网的高温蒸汽(热水)作为吸收式热泵发生器热源的地源热泵系统,利用空气源热泵保障地下换热系统热平衡。介绍了复合系统的运行模式,确定了系统的运行控制策略,选取哈尔滨地区某办公建筑对系统的全年运行性能进行分析。通过计算,系统平均综合性能系数为2.1,相比传统的供暖空调方式节能33.1%。该系统全年运行土壤取/排热不平衡率为3.8%,可以保证土壤温度场以年为周期的热平衡;系统可以长期稳定运行。     

地源热泵空调系统设计实例分析

以烟台地区某公共建筑为例,借助HDY-SMAD全年动态负荷模拟软件对建筑物的冷热负荷进行模拟计算,根据全年能耗分布曲线图、季节性能耗分布曲线图和全年负荷频率分布图进行冷热源的匹配,并从室外土壤换热系统及室内空调通风系统两方面对地源热泵空调系统进行了全面介绍;最后通过经济性比较,说明了地源热泵空调系统在节能环保方面的优势.     

地埋管地源热泵系统冬季运行节能分析

通过对地埋管地源热泵系统冬季运行工况的检测,采集实际运行数据,分析系统耗能设备及耗能形式。对整个系统冬季运行效率进行理论、实际测量计算,研究不同节能措施对集中空调系统制热性能系数的影响,旨在说明设计、安装、运行管理水平对系统节能的重要性。     

不同冷源方式下空调系统CEC的研究

利用空调系统能耗系数（CEC）分析不同冷源方式下空调系统的能耗,对不同地区酒店分别采用普通螺杆式冷水机组＋燃气热水炉和地源热泵机组作为冷源方式的空调系统能耗水平进行计算,结果表明,采用地源热泵机组为冷源的空调系统更节能,地理位置对CEC也有影响。     

太阳能-地源热泵复合系统的实验研究

地源热泵是利用可再生能源地热能的一种高效热泵系统,是未来发展的趋势。但在我国北方地区,大部分以热负荷为主,冬季地下埋管的取热量高于夏季的释热量,长期运行会破坏土壤温度场。介绍了太阳能-地源热泵复合系统,通过实验验证了太阳能辅助系统能够有效恢复土壤温度,提高系统性能系数,可以实现热泵长期稳定的运行。     

山东某政府办公楼空调系统节能改造方案

结合既有空调系统的耗电量及当地采暖度日数,计算政府办公楼的全年能耗,进而提出该项目的改造方案为地源热泵与原有空调机组相结合的复合系统,该方案使得该办公楼每年节约标准煤8.48 kg/m2,运行费用每年节省22.2元/米2。     

Insertion of triangulated surfaces into a meccano tetrahedral discretization by means of mesh refinement and optimization procedures

In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

Flow calorimeter for enthalpy increment measurements on condensed gases

A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.     

Refrigerators Enter a New Era of Health Preservation Frestech initiates the establishment of China's first standard for household sterilization refrigerators

On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.……     

Optimum-Simulation von Ernteprozessen

Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.     

A study of centrifugal cast high boron high speed steel

In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M₂(B,C), (W,Mo)₂(B,C), M₃(B,C), M₂₃(B,C)₆ type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm². The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K₁ mill housing of bar mill.     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……     

Deposition and Coating Properties on CVD Tungsten

Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.