流体输送纠偏技术在中央空调水系统中的应用

中央空调运行的能耗主要由三部分组成：一是制冷主机；另一是风机盘管等末端设备；还有就是冷却水、冷媒水输送系统，也就是水泵能耗。水泵能耗约占整个中央空调系统的35％左右。     

新型压缩吸收耦合的太阳能热泵系统实验研究

提出一种太阳能吸收子系统过冷压缩循环的新型压缩吸收耦合热泵系统,由压缩子系统、吸收子系统和太阳能集热子系统3部分组成;在夏冬两季均可使用。针对该新型太阳能热泵在恒定工况下的制冷、制热性能进行稳态实验研究。实验结果显示,夏季制冷时,在冷冻水进口温度12℃,冷凝器出口制冷剂温度50℃时,新型太阳能热泵系统的制冷最低COP为4.02,与同工况的常规压缩热泵相比,制冷COP提高13.88%;冬季制热时,存在COP的极值转变温度。在实验环境温度为16℃,冷凝器热水出口温度59℃时,新型耦合系统最小的制热COP为5.44,与同工况常规压缩热泵相比,制热COP提高11.52%。显示了新型系统的巨大优势,具有良好的应用前景。     

空调冷却水系统变流量分析

当前,以变频技术为核心的节能技术开始在中央空调系统普及使用,主要在冷冻水系统、冷水机组2个子系统中广泛应用。但由于诸多原因,冷却水子系统变频变流量节能技术尚未推广。通过热力学理论分析冷却水子系统变频变流量的可行性,并结合工程实例分析其节能效果。理论与实例表明,冷却水变流量可行,节能潜力可观,运行能耗明显降低。     

中央空调系统技术经济分析

首先介绍了国内外空调节能发展现状,然后从冷却水系统、冷冻水系统、空气处理系统、和空调其他系统四个方面对中央空调节能进行了分析。并以南方某办公大楼为例,对主要能耗部分做了节能计算,可供类似中央空调设计计算借鉴和参考。     

基于喷射制冷和除湿溶液再生的复合冷源系统优化及应用

结合低温工业余热特点和夏季空调系统温、湿度调节需求,该文根据梯级用能原理提出基于喷射制冷和除湿溶液再生的复合冷源系统,以实现工业余热的回收利用。采用数值模拟手段分析低温工业余热温度、冷冻水温度和热湿比对该复合冷源系统性能的影响。研究表明,随着低温工业余热温度和冷冻水温度的升高以及热湿比的降低,该复合冷源系统的COP增大。该复合冷源系统的COP在热湿比较大的条件下,主要受喷射制冷子系统性能的影响;在热湿比较小的条件下,主要受除湿溶液再生子系统性能的影响。该复合冷源系统具有较大的节能潜力和较好的环保效益,可用于高效回收低温工业余热。     

中央空调制冷系统中变频技术的问题探讨

中央空调可以使得建筑物室内的温度达到一个舒适的状态,伴随着人们对居住环境要求的提高,中央空调得到了广泛应用,但中央空调由于其设计得不合理,导致能量损耗巨大,而变频技术针对中央空调在耗能损失过大的不合理之处应运而生。就中央空调的主机制冷系统、冷冻水循环系统与冷却水循环系统的制冷原理,以及变频技术对这3个系统的控制作用进行了探讨。     

太阳能泵压缩制冷装置

1概述当今，国民经济生产和人们生活均用电制冷。冷冻、冷藏、空调降温已成为能源消费主要组成之一，尤其是在夏季，制冷耗电猛增。在目前能源发展过程中，能源消耗结构，一方面自给率逐步走低，另一方面煤炭消费一直保持较大比重，导致能源供应和交通运输局面极为严峻。为此，确定合理的可行的能源消耗结构，如何充分利用能源资源特点，是能源发展中极为重要的问题。利用太阳能制冷，其主要优点是能有效吸收太阳能和消耗自然冷（风、水），在这种情况下，它的效益是双倍的，因为太阳的照射被太阳能收集器所遮盖，不仅减少了这部分照射热能…     

化纤厂节能问题探讨

根据化纤厂暖通空调系统是企业能耗大户的特点，对热力系统冷凝水回收利用与采暖耗能、冷冻系统制冷机组本身性能优化及工艺运行调节、冷冻水和冷却水系统的水质控制及循环冷却塔的性能优化、空调系统过渡季节节能等方面进行分析，总结出耗能原因，并提出相应的节能措施。     

太阳能喷射/压缩复合制冷循环性能研究

研究了一种太阳能喷射/压缩复合制冷循环,由太阳能集热子系统、喷射制冷子系统及压缩制冷子系统组成,系统充分利用热电两种能源以及两种制冷方法各自的优点,优化喷射制冷子系统工作性能的同时,改善压缩式子系统的工作条件,从而提高复合制冷循环性能的同时节约高品位电能。采用性能较好的高蒸发温度式喷射制冷带走压缩机排气余热具有实际意义。通过数值模拟的手段分析系统性能及其主要影响因素,并优化工作条件。研究表明,与相同工作条件下的单压缩制冷循环相比,复合制冷循环工作日全天候运行时电力性能系数提升约为31.5%,节电优势显著。存在一个最佳的喷射子系统蒸发温度使得复合制冷循环性能系数达到运行工况的最大值。     

某综合楼空调通风节能设计

探讨移动通信综合楼的空调通风形式，着重阐述选用冷冻水型机房专用空调器的优点、应该注意的问题及本工程所采取的措施，并介绍了中央空调冷源、水系统、空调末端装置、通风防排烟系统及自控等的设置情况，以及空调系统节能设计的重要性。     

唱响春天里的歌

春的脚步蹒跚将至。春节刚过。料峭春寒中,2月9日、12日,北京终于迎来入冬以来久违的降雪。在故宫墙外,在北海公园,人们拿着相机记录着今冬的雪,享受着银装素裹下红墙碧瓦的美丽。心情就像一只只快活的小鹿在一望无垠的草地上时而奔跑,时而嘻戏,时而偎依在母亲身旁。人们的心里、喉咙里唱着春天里的歌。     

通用外径检具在气缸套加工中的应用

1引言气缸套是发动机的核心零部件,气缸套质量直接影响到发动机的功率和排放指标,国家修订的气缸套标准越来越等同于欧标排放标准,随着近几年进军多缸机的厂家逐步扩大,我国大中型柴油机厂猛增几十家,     

节能量的计算方法及在节能审核中的应用

节能量的准确计算在节能审核中越来越重要。文中详细阐述节能量的计算、边界确定和在实际中的应用,增加审核的可靠性、真实性,同时介绍在燃煤锅炉(窑炉)、余热余压利用项目、电机系统节能、及能量优化系统优化项目的计算方法。     

Understanding the ROC transfer payment in the renewable obligation with the recycling mechanism in the United Kingdom

The Renewable Obligation scheme was implemented to promote renewable energy for electricity supply in the UK over 15 years from 2002 to 2017. Renewable Obligation Certificates (ROCs) were allocated to accredited generators for receiving additional revenues from selling those certificates to electricity suppliers. In particular, a recycling mechanism was employed in this scheme. That is, the penalties on missing ROCs from all suppliers are paid into the buy-out fund, which is then redistributed to suppliers in proportion to the number of ROCs they presented. This mechanism complicated the ROC trading in three aspects. First, the recycling mechanism induces strategic behaviour between suppliers in fulfilling the obligation of purchase of ROCs, leading to the equilibrium of a lower transfer payment from suppliers to generators, compared with the scenario without the mechanism. Secondly, under the recycling mechanism, the existence of vertical integration encourages upstream competition between generators, reducing ROC prices and the transfer payment. Thirdly, suppliers may strategically collude with each other to take the advantage of the recycling mechanism, but the existence of vertical integration weakens the collusion and prevents the worst case of nearly zero transfer payment.     

Energy efficiency and the slump in labour productivity in the USA

Energy consumption is included in an aggregate Cobb-Douglas production function for the USA. The data suggest that energy conservation has not reduced the growth rate for real GNP by more than 0.3 percentage points and that less than one-fifth of the overall slump in labour productivity since 1973 should be attributed to higher energy prices.     

Estimating the agricultural demand for electricity in the presence of measurement error in the data

This paper begins by discussing some of the problems frequently encountered in obtaining demand elasticity estimates. To these problems is added that associated with inaccuracy in the measurement of the dependent variable and one or more of the independent variables that impact upon the quantity demanded. Two diagnostics — the regression coefficient bounds and the bias correction factor — are introduced to assess the effect that such a measurement error has on the estimated coefficients of demand relationships. Use of these diagnostics aids in assessing the integrity of the estimates obtained. In considering the demand for electricity for irrigation and the demand for electricity for other (non-irrigation) uses by farmers in the USA, both the quantity demanded and the unit price data available for demand model estimation purposes contain measurement errors. The regression coefficient bounds diagnostic is used to indicate a range over which the true price responsiveness of farmers to changes in energy prices lies. The results suggest that each 1% increase (decrease) in the price of energy will result in between a 0·51 and 0·35% decrease (increase) in the quantity of electricity demanded for irrigation and between a 0·43 and 0·17% decrease (increase) in the quantity of electricity demanded for other uses. The bias correction factor is computed to evaluate the magnitude of the under-estimation of the responsiveness of the quantity of electricity demanded for irrigation and electricity for other uses to a change in the number of acres irrigated and the number of acres planted. For electricity for irrigation, the under-estimation was 14·1% while, for electricity for other uses, it was 13·9%.     

Meeting the challenges in the transport sector

This paper provides an industry leader's perspectives on the potential for transportation fuel cells, reviewing their development progress, describing their advantages and barriers, and identifying paths to successful commercial deployment. UTC Power has developed proton exchange membrane (PEM) fuel cell technology for transportation since 1998, building upon applicable innovations from the company's space fuel cell and stationary fuel cell programs. PEM fuel cell durability improvements are discussed, highlighting achievements in the understanding of decay mechanisms and the design of effective mitigations. The potential for high-volume production to make automotive fuel cells cost competitive with internal combustion engines is explained. The paper underscores the important role that initial deployment of PEM technology for transit buses can play, although development of automotive fuel cells must continue in parallel as the hydrogen infrastructure develops. Suggestions are offered on how policies and regulations, communication and education, and improved codes and standards can all help to promote the widespread use of fuel cells in transportation.     

可调式汽封在215MW 机组汽封改造中的应用

可调式汽封可以减少动静间的碰磨造成的汽封磨损,保持较小的汽封间隙,使泄漏蒸汽量减少,提高机组运行热效率,同时,也能够增加机组的安全可靠性。     

叶片动应力计算的重要改进及其在不调频叶片设计上的应用

叶栅流场中的叶片受流道中汽流力的作用，同时也承受了流道中谐波汽流力的激振。由于谐波汽流力沿周向波动，其对叶片的激振力应该是流道宽度内谐波激振力的积分。本着这一观念对ASME早期发表的动应力基本方程进行改进，重新作了推导，并指出了降低叶片共振应力的途径。多年来已取得了成功应用，其中涉及带冠单叶片的动强度特性及不调频叶片事故处理的材料综合抗振强度对比分析，对工程实践具有一定的参考借鉴的价值。     

地源热泵制冷工况间歇运行的实验研究

地下埋管内的水温主要与埋管换热器的长度、地下土壤温度、土壤的热物性及系统运行模式等因素有关。如果能找出系统最佳运行模式,对于地下温度场的恢复、系统运行优化以及减少埋管换热器的造价都有重要意义。本文就是基于这样的目的,通过人为控制机组的运行模式,探求连续运行及间歇运行模式下埋管换热器内水温的变化规律,以期找到地下换热系统运行优化的最佳手段。