采用混合自然工质的自复叠制冷系统热力性质分析

对R744／R290、R744／R600a混合自然工质的热力性质进行分析比较,并将它们用于自复叠制冷循环,对系统的循环特性进行分析。经过计算,得出了两种混合工质制冷性质的不同点及环境温度、制冷温度、混合工质中R744浓度对系统性能的影响。为今后R744／R290、R744／R600a的实验研究和实际应用提供了理论依据,减少了实验的工作量。     

基于低品位余热驱动的正逆耦合空调系统性能分析

针对低品位余热的利用,将有机朗肯系统与复叠式制冷系统耦合,建立了热力学模型;采用R141b作为朗肯循环系统制冷工质,分别采用R22/R23、R404A/R23、R290/R744、R717/R744四种工质对作为复叠式制冷系统高低温级循环的制冷工质;基于EES软件编写了循环性能计算程序,研究了低温级冷凝温度T_(10)、低温级蒸发温度T_e、蒸发冷凝传热温差ΔT对系统性能COPs以及高低温级质量流量比G的影响,并以COPs与G为评价指标选出最佳工质。结果表明系统的COPs会随着低温级冷凝温度的升高而先增大后减小,并存在一个最佳值;系统COPs随着低温级蒸发温度的升高而增大,随着蒸发冷凝传热温差的增大而减小;高低温级质量流量比随着低温级冷凝温度的增大而减小;R717/R744最适合作为有机朗肯-复叠制冷系统复叠制冷部分工质。     

混合工质脉管制冷机性能的数值模拟

开发了适用于混合工质的脉管制冷机的计算程序，利用此程序对应用混合工质提高脉管制冷机的制冷性能进行了研究，发现当混合工质采用氦气和氢气，且处于合适的配比下，可以进一步改进脉管制冷机的制冷性能，给出了当混合工质最佳配比时，脉管制冷机内热力参数的瞬时变化及一周期的循环参数，用该计算程序可以获得混合工质脉管制冷机内复杂过程的详细信息，为制冷机设计和改进提供依据。     

热管喷射制冷循环工质的研究

文章研究了水、甲醇等6种工质在热管喷射式制冷循环中的工作特性。计算结果表明，工质的冷凝温度对系统COP的影响比较大，在发生温度一定的情况下，较低的冷凝温度和较高的蒸发温度能有效提高系统的COP，在各种运行条件下，甲醇、R11、R123等工质有较高的COP。     

热泵系统用R744/HCs混合工质配比范围研究

针对现有碳氢类(HCs)工质进行综合分析比较,选定了一些适用于热泵系统的R744/HCs非共沸混合工质对。通过对选定的混合工质临界参数和温度滑移特性的进一步计算分析,确定了其适用的热泵循环,并建立了快速确定亚临界循环热泵系统用R744/HCs非共沸混合工质中R744质量配比范围的计算程序。结合热泵热水器的工况及高压侧压力的要求,利用计算程序确定了R744/R600、R744/R600a、R744/R601和R744/R601a的质量配比范围。     

低品位热驱动的混合工质喷射制冷循环研究

提出一种低品位热驱动的混合工质喷射制冷循环,将沸点相差较大的非共沸混合工质引入喷射制冷循环,采用两级分凝分离降低该新循环压比,实现在喷射制冷循环中获得较低的制冷温度和较高制冷效率。建立组成循环各部件热力学数学模型,在系统稳定运行的条件下,分析喷射器压比、冷凝温度和混合工质组分配比对新循环工作性能的影响。研究表明:采用混合工质R600/R290的喷射制冷循环可获得低于-20℃的制冷温度。     

自然工质复叠式制冷循环替代与节能研究

通过对自然工质R290／CO2和NH3／CO2与常规工质R22／R13的复叠式制冷循环的热力学分析，得出P290／CO2复叠式制冷循环的COP比常规工质R22／R13的低，提出CO2低温循环采用膨胀机代替热力膨胀阀，从而提高了COP。在NH3／CO2复叠式循环的NH3高温循环和CO2低温循环中都采用膨胀机代替热力膨胀阀，可以大大地提高COP。自然工质P290／CO2和NH3／CO2替代常规工质R22／R13复叠式制冷循环有很好的前景。     

自然工质复叠式制冷热泵系统的性能分析

介绍了以自然工质CO2为高温循环工质,R290为低温循环工质,同时制冷和供热的CO2/R290复叠式制冷热泵系统,通过对CO2/R290复叠式制冷热泵系统的性能分析,得到了气体冷却器的入口压力和出口温度,复叠式循环的蒸发温度,低温循环的冷凝温度对复叠式制冷热泵系统性能的影响,为今后的CO2/R290复叠式制冷热泵系统的优化设计和开发应用打下了一定的基础。     

采用不同工质的高温复合热泵开水器特性研究

热泵开水器具有较高的能源利用效率,是公共场所电加热开水装置的理想替代品。从提高能源效率和一机两用的角度,构建了一种高温复合热泵开水器系统。建立了系统热力学模型,选R236fa、R245fa、R365mfc、R245ca、RC318和R236ea等6种较高临界温度的制冷工质,通过能量分析和[火用]分析的方法,探讨了不同制冷工质对高温复合热泵开水器系统性能的影响。研究结果表明:R245fa作为工质的高温复合热泵开水器系统具有最佳的性能,而以RC318作为工质的系统性能最差。在给定工况下,R245fa作为工质系统制热性能系数(COP_h)为2.47,而其制冷性能系数(COP_c)为3.37,[火用]损失和[火用]效率分别为9.47 kW和49.07%;与R245fa相比,RC318作为工质系统的总能耗增加了39.53%。     

太阳能驱动喷射复合压缩式制冷空调系统设计

为北京市某综合楼设计了一种喷射复合压缩式制冷空调系统,阐述其运行原理、负荷计算、R245fa为工质的喷射式制冷设计计算、空调系统设计计算及选型等,通过对比新复合式空调系统和传统压缩制冷系统的能耗,得出新复合式空调系统可节电23.18%,系统性能提升超过30%,认为其具有一定的发展前景。     

WE-NET: Japanese hydrogen program

The Agency of Industrial Science and Technology (AIST), in the Ministry of International Trade and Industry (MITI), started the New Sunshine Program in 1993 by unifying the Sunshine Program (R and D on new energy technology), the Moonlight Program (R and D on energy conservation technology), and the Research and Development Program for Environmental Technology. The objective of the new program is to develop innovative technologies to allow sustainable growth while solving energy and environmental issues. One of new projects in this program is the “International Clean Energy System Technology Utilizing Hydrogen (World Energy Network)”: WE-NET.The goal of WE-NET is to construct a worldwide energy network for effective supply, transportation and utilization of renewable energy using hydrogen. The WE-NET program extends over 28 years from 1993 to 2020. In Phase 1, we started core research in areas such as development of high efficiency technologies including hydrogen production using polymer electrolyte membrane water electrolysis, hydrogen combustion turbines, etc.     

A decision analysis of the U.S. breeder reactor program

Past modelling efforts have failed to reach a consensus on breeder R & D strategy. These failures have led some to question the usefulness of benefit-cost analysis for a problem as complex and as politicized as this one has become. Our paper examines some of the major weaknesses of past benefit-cost analyses and then reformulates the breeder investment decision in a decision tree framework. Decision analysis is used to evaluate alternative R & D strategies that range from accelerating the current effort to abandoning the entire program.

Breeder benefits are assessed through ETA-MACRO, a model of interactions between the energy sector and the rest of the U.S. economy. A dynamic non-linear optimization procedure is used to examine how breeder timing could depend upon alternative assumptions with respect to:

1. (a) uranium supply,

2. (b) energy demand growth,

3. (c) environmental constraints upon coal and shale oil production, and

4. (d) the availability of alternative energy sources.

Subjective probabilities have been estimated through a Delphi questionnaire on the critical uncertainties. Each individual's responses have been used independently to calculate an optimal strategy. A fairly simple rule-of-thumb has emerged from this experiment. If a respondent believes that the probability of positive benefits (P) exceeds 0.03, there are positive expected dollar benefits from any breeder development program. If P is less than 0.03, however, the expected economic benefits of such a program would be negative. The costs of the R & D program would then exceed their actuarial value.     

中温地热能驱动的跨临界有机朗肯-蒸气压缩制冷系统的性能分析

跨临界有机朗肯?蒸气压缩制冷系统可以使工质与地热流体更好地匹配,减小系统的不可逆性。本文建立该系统的热力学模型,利用EES软件编程,分别对以R143a、R218及R125为工质的系统进行性能分析。计算结果表明,相比R218及R125,以R143a为工质的系统的性能是最佳的。为了避免膨胀机内产生湿蒸气,对于一定的膨胀机进口温度,膨胀机入口存在一个极限压力,并且存在一个最优压力使得系统的性能最佳。地热流体温度的升高可以提高系统的制冷能力,但系统的性能系数则随之先增大后减小;随着地热流体干度的增加,地热流体释放的潜热会大大增加系统的制冷量,而系统的性能系数保持不变。冷凝温度及蒸发温度对系统性能有着重要影响,其中冷凝温度的影响更为明显。以R143a为工质的跨临界有机朗肯?蒸气压缩制冷系统的最佳性能优于以R245fa为工质的亚临界有机朗肯-蒸气压缩制冷系统的最佳性能。     

小型柴油机曲轴生产线新工艺的应用研究

介绍了R175小型柴油机曲轴的结构特点及生产线的工艺设计流程。为强化曲轴在生产过程中质量的稳定性和一致性，提高其制造质量和效率，本文重点对生产线所采用的新工艺作了应用研究。     

Performance analysis of new alternatives to HCFC‐22 inside air/refrigerant‐enhanced surface tubing

In this paper, the test results of a performance analysis of new alternatives; R‐410A, R‐507, R‐407C, R‐408A and R‐404A proposed as substitutes to HCFC‐22 are presented. The test results were obtained using an air‐source heat pump with enhanced surface tubing. Performance tests were conducted according to the ARI/ASHRAE Standards. The performance data demonstrated that as an interim replacement, the R‐404A blend has a superior performance particularly at low temperatures among the proposed blends. Furthermore, the alternatives to R‐22 are characterised by high discharge pressure compared to that of R‐22. In particular, R‐410A has the highest discharge pressure among the blend studied. R‐407C has similar discharge temperature to R‐22 at temperatures lower than −8°C. Copyright © 2000 John Wiley & Sons, Ltd.     

混合工质R134a/R23替代R22的可行性研究

叙述了基于新型环保型混合制冷剂R134a/R23替代制冷剂R22的问题,以及通过REFPROP7.5,对混合工质R134a/R23从物性和热力学特性进行的理论计算分析,指出,由质量分数为70%的R134a和质量分数为30%的R23组成的混合制冷剂与R22性能最为接近,在变工况运行条件下,其COP值比R22高8%左右,其冷凝压力比同条件下用R22作为循环工质低21%～36%,理论上完全具有替代R22的可能性。     

The Use of New Refrigerants in Compact Heat Exchangers for the Refrigeration Industry

The present article reports on the results of experimental research carried out on compact plate heat exchangers, currently used as evaporators and condensers in refrigeration loops. The research was aimed at getting information on the thermal efficiency of the heat exchangers, under reference commercial conditions, when using new ozone-friendly refrigerants to replace CFCs and HCFCs. Specifically, the influence of some thermal-hydraulic parameters on the heat flux and the overall heat transfer coefficient are investigated for evaporators, using R134a, R407C, and R410A, three fluids proposed to replace R22, and HCFC, currently the most common refrigerant used in residential and commercial air conditioning equipment. Moreover, in this article a new thermodynamic method has been applied with the purpose of defining the saturation temperature and investigating the other main parameters for mixtures in the two-phase region for the fluids R407C and R410A, which are blends of, respectively, three and two pure refrigerants.     

锅炉房设计方案对系统节能及环境效益的影响分析

介绍一个有效治理锅炉房噪音、同时具有更佳系统节能和环境效益的设计新方案 ,并对该方案提出了传热计算简化模型。利用此模型分析了该方案节能及环保效益的各种影响因素 ,提出设计中应采取的措施及该方案的技术性限制 ,可供广大设计人员及能源环保工作者参考。     

中国能源研发（R＆D）政策研究概要

该课题主要研究21世纪国内外新形势下的能源R&D的政策问题。主要研究评价能源R&D资源配置与投入,同时研究评价能源R&D计划的从立项到促进R&D成果产业化管理,能源R&D计划管理的政策分析是该研究的又一任务。     

PVTx Study of Binary System R22／R152a with Burnett Method

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