摩擦对空气标准Dual循环性能的影响

建立一类空气标准Dual循环的不可逆模型，考虑压缩过程和做功率程的有限时间特性和循环的摩擦损失对其 影响，推导出功率，效率与压缩比关系的解析式，结合数值算例，所得的功率效率曲线与实际同特性相同。     

回热式布雷顿热泵热力循环参数分析

用有限时间热力学方法分析实际热泵循环性能。优化高、低温侧换热器和回热器之间的热导率分配式或传热面积分配和工质与热源间的匹配（对变温热源），可得循环最优特性。给出了详细的数值算例分析各不可逆损失对循环特性的影响     

包含五种循环的普适定常流内可逆制冷循环最优性能

用有限时间热力学方法分析了一类普适定常流内可逆制冷机循环,导出了存在传热损失时,由一个吸热过程、一个放热过程和两个绝热过程组成的一类普适的定常流内可逆制冷机循环的制冷率、制冷系数、(火用)损失率、(火用)输出率和生态学性能,并由数值计算分析了循环过程对循环性能的影响特点.所得结果包含了内可逆Carnot、Diesel、Otto、Atkinson和Brayton制冷循环的特性.     

包含七类循环的广义不可逆普适制冷循环最优性能

用有限时间热力学理论和方法分析了热漏、热阻和其它不可逆性对定常流普适制冷循环模型性能的影响,导出了由两个绝热过程、两个等热容吸热过程和两个等热容放热过程组成的不可逆制冷循环的制冷率、制冷系数、炯损失率、炯输出率和生态学性能,并由数值计算分析了循环过程对循环性能的影响特点。所得结是包含了存在热阻、热漏和内不可逆损失的Diesel、Otto、Brayton、Atkinson、Dual、Miller和Camot制冷循环的特性。     

传热不可逆回热式布雷顿制冷机分析

用有限时间热力学方法分析实际隐态制冷装置性能，导出了恒温和变温热源条件下实际闭式回热式布雷顿制冷循环制冷率与压力比和制冷系数与压力比之间的解析关系。考虑了不可逆性包括高，低温侧换热器和回热器的不可逆传热损失，压缩机和膨胀机中的非等熵压缩和膨胀损失，以及管路系统中的压力损失，通过优化两个换热器和回热器之间的热导率分配或传热面积分配可得循环最优性能，由数值算例给出了各项损失对循环制冷率和制冷系数的影响。     

空气源热泵热水器性能对比态分析法

提出一种空气源热泵热水器性能对比态分析法:以热泵循环的热力学分析为基础,通过对标准工况的理论特性参数的对比,得到该方法中的无量纲理论对比特性参数;通过实际情况的输入功和热损失的分析,得到无量纲实际影响因素修正系数;再以实际标准工况的特性为对比基准,得到无量纲的实际对比特性参数,从而建立实际对比特性参数与理论对比特性参数的关系;最后拟合出实际对比能效比和实际对比热水量的计算式。实用中,只须结合标准工况的实测值,即可由该方法求得变工况的实际热泵性能系数和实际出水量。该方法使热泵热水器性能的理论分析与实际相结合,修正理论结果与实际情况的偏差,简化复杂的计算模型,取得满足工程需求的精度,其无量纲对比特性参数计算式具有普适性。     

氢氦混合工质脉管制冷性能研究

由于氢气具有优越的传热和流动特性,有望减少脉管制冷机回热器的流动和传热损失,从而可获得高于纯氦工质的制冷性能.从氢组分对循环热力学性能、流体流动与传热性能等因素的影响角度出发,开展了氢-氦混合工质脉管制冷性能研究,并在30 K温区进行了实验验证,获得了比纯氦更好的制冷性能.     

普适定常流内可逆制冷机循环模型的炯经济性能优化

用有限时间热力学方法分析工作在恒温热源TH、TL之间内可逆普适制冷机循环模型的炯经济性能，导出循环利润率与工质温比、制冷系数与工质温比的关系式，和利润率与制冷系数的特性关系。所得结果包含了内可逆Carnot、Diesel、Otto、Atkinson和Brayton制冷循环的有限时间炯经济性能。     

阀门控制的金属氢化物制冷系统的热力学分析

建立了阀门控制的金属氢化物制冷系统的动态性能模型，针对阀门控制的金属氢化物制冷系统，分析了热源温度、反应器的比热、氢化物与反应器质量比、传热系数等对系统动态性能的影响。结果表明：中温热源温度的增高将会降低COP、炯效率和制冷率；反应器的比热容对COP、炯效率和制冷率影响较小；增加氢化物与反应器质量比时COP、炯效率将增加，但制冷率将下降；增加传热流体与反应床表面的传热系数将会较明显提高COP、炯效率和制冷率。根据计算结果提出了改善系统动态性能的措施。     

多轴特种车辆传动系统机械摩擦阻力损失与传动效率研究综述

在多轴特种车辆重载化和机动化的发展过程中，动力传动性能是其快速机动作战能力的保证，也是战时生存能力的一种体现。传动系统的内部阻力损失会使动力传输效率下降从而直接影响动力性能，其中机械摩擦阻力损失是传动系统主要损失。该文章围绕传动系统机械摩擦阻力损失特性与传动效率研究方法，首先分析了多轴特种车辆传动系统的结构特殊性，表明了传动效率对传动系统性能的重要性；其次通过分析齿轮啮合功率损失、轴承摩擦功率损失、油封功率损失和传动轴功率损失4种主要类型机械摩擦阻力损失的形成机理、主要影响因素，表明了传动效率与部件结构参数、运行条件之间的关系，为传动系统性能表征提供了分析依据；然后从理论数值研究、仿真研究和试验论证研究3个方面综述传动系统效率的研究核心与难点，为实现对车辆传动部件的优化设计与状态监测、传动系统的优化匹配与性能评估提供指导思路；最后阐述了对当前传动效率特性研究深度的展望，认为多因素的耦合分析、不确定性分析，功率损失的动态特性分析，以及基于车辆行驶工况的综合传动效率分析更具有工程应用价值。     

一个柴油机驱动的复合制冷循环

介绍了一个用柴油机驱动的复合制冷循环，即用柴油机主机带动压缩式循环，同时利用柴油机排气和缸套水的热量作源驱动吸收式循环。热力学分析和数值计算表明，此复合循环由于实现了不同品位热源的合理利用，减少了不可逆损失，其能效比普通式循环或直燃式吸收循环可分别提高19％和58％。     

Effect of Heat Transfer on the First and Second Law Efficiency Analysis and Optimization of an Air-standard Atkinson Cycle

In this paper, the first and second-law analysis for the thermodynamic air-standard Atkinson cycle with an account for heat transfer is performed using finite-time thermodynamics. In order to have more accurate evaluations, the effects of thermodynamic and design key parameters on the performance characteristics of Atkinson cycle are shown. Further, artificial neural network and imperialist competition algorithm are employed to predict and optimize the net work output value versus the minimum cycle temperature and also the compression ratio. The results obtained show that the heat loss is an effective factor of the performance of the cycle and it should be considered in the analysis and comparison of practical internal combustion engines.     

变温热源不可逆布雷顿制冷循环制冷率和制冷系数优化

用有限时间热力学方法分析变温热源不可逆简单布雷顿制冷循环的特性,分别以制冷率和制冷系数为优化目标,优化了循环中换热器的热导分配以及工质和热源间的热容率匹配,并采用数值计算分析了压比、换热器总热导、压缩机和膨胀机效率、工质热容率等参数对最优制冷率和制冷系数的影响特点.所得结果对工程制冷系统设计有一定的指导意义.     

A theoretical study on a novel combined power and ejector refrigeration cycle

A new combined power and refrigeration cycle is proposed for the cogeneration, which combines the Rankine cycle and the ejector refrigeration cycle by adding an extraction turbine between heat recovery vapor generator (HRVG) and ejector. This combined cycle could produce both power output and refrigeration output simultaneously, and could be driven by the flue gas from gas turbine or engine, solar energy, geothermal energy and industrial waste heats. Parametric analysis and exergy analysis are conducted to examine the effects of thermodynamic parameters on the performance and exergy destruction in each component for the combined cycle. The results show that the condenser temperature, the evaporator temperature, the turbine inlet pressure, the turbine extraction pressure and extraction ratio have significant effects on the turbine power output, refrigeration output, exergy efficiency and exergy destruction in each component in the combined cycle. It is also shown that the biggest exergy destruction occurs in the heat recovery vapor generator, followed by the ejector and turbine.     

Analysis of a hybrid compression—absorption cycle using lithium bromide and water as the working fluid

Hybrid refrigeration cycles which combine a mechanical compressor and an absorption cycle in such a way that they share a single evaporator were analysed. The motivation for the investigation of hybrid cycles was the need to more efficiently utilize the output of an internal combustion engine. The hybrid cycles make efficient use of both the work and the heat output of an engine. Performance calculations are reported for a promising cycle which utilizes LiBr-H₂O as the working fluid. For this working fluid, the refrigerant is water. Owing to the potential sensitivity of the absorption cycle components to oil contamination, the cycle was analysed assuming an oil-free steam compressor (screw design). Although oil-free steam compressors are available, they are used only sparingly in the industry. The capital cost for such a compressor is very high and the isentropic efficiency of the available units is low. This combination of high cost and low performance results in poor economics for the hybrid cycle based on the available technology. However, the cycle has significant potential from a thermodynamic viewpoint and it provides an incentive for compressor manufacturers to refine the oil-free steam compression technology.     

Working fluids comparison and thermodynamic analysis of a transcritical power and ejector refrigeration cycle (TPERC)

The combined power and cooling cycles driven by waste heat and renewable energy can provide different kinds of energy forms and achieve a higher thermodynamic efficiency. However, only a few researchers have focused on the improvement of temperature matching between the heat source and working fluid. This paper proposes a transcritical power and ejector refrigeration cycle (TPERC) to improve temperature matching between the heat source and working fluid. Based on the modelling of the TPERC system, a comparison of working fluids and the effects of system parameters on the cooling capacity, work output, thermal efficiency and exergy efficiency are discussed. The results show that of the seven working fluids selected, R1234ze has the largest thermal efficiency and exergy efficiency, principally due to having the highest critical temperature. At the identical turbine back pressure, condensing temperature and evaporation temperature, the turbine inlet temperature and its corresponding generation pressure have little impact on thermal efficiency.     

Theoretical assessment of an ejector enhanced oil flooded compression cycle

Compressor loss and throttling loss are major thermodynamic losses in basic vapor compression cycle. For this reason, an ejector enhanced oil flooded compression cycle is proposed. To evaluate the performance, a mathematical model is established and the performance of this cycle with R32 as the working fluid is investigated. Furthermore, basic cycle, ejector enhanced basic cycle and oil flooded compression cycle have also been investigated. The comparison results show that the developed cycle has a maximum of 4.3% and 4% COP improvement at the evaporation temperature of −25 °C and the condensation temperature of 45 °C over the oil flooded compression cycle and the ejector enhanced basic cycle respectively. In addition, the effects of internal heat exchanger on the developed cycle are also studied. In comparison to the ejector enhanced basic cycle with 50% efficient internal heat exchanger, the COP improvement of the developed cycle rises up to a maximum of 8.5%. The results show that the proposed cycle has large potential applications for the ejector cycle enhancement.     

采用主动式磁蓄冷器(AMR)的室温磁制冷机数值模拟

对采用主动式磁蓄冷器(AMR)的室温磁制冷机的工作进行了模拟计算,给出不同工作温区、不同磁场强度、不同换热流体时机器的制冷能力变化、COP及热力学完善度变化趋势的预测,并对在固定周期式和可变周期式下运行时的情况进行了对比,后者的制冷能力、COP及热力学完善度都优于前者.     

利用燃气轮机烟气余热的复合有机朗肯循环系统优化分析

本文针对燃气轮机烟气余热设计了一种复合有机朗肯循环系统,对其进行了详细的热力学分析,以某燃驱压气站烟气条件(400℃,26 kg/s)为例,以系统净输出功为目标,利用Matlab和Refprop 9. 0选择了13种工质,并确定了系统最优工况。结果表明,甲苯、R141b、丙酮分别作为3个子系统的工质时,系统可实现最大净输出功为1 587 k W,热效率和火用效率分别可达20. 26%和42. 68%,比单级循环可实现的最大净输出功高23. 33%。对系统各部件进行火用损失分析,发现蒸发器火用损失最大,并提出了改进方案。