不可逆联合制冷循环的重要设计参数

建立一类存在热阻，热漏和内部耗散的定常流态联合制冷机循环模型，并研究其性能优化，导出制冷系数，制冷率基本优化关系和最大制冷系数及其相应的制冷率，给出了传热面积的最佳值工质最佳工作温度。所得结果适用于由任意个制冷机串接而成的联合制冷循环。     

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.     

考虑热漏损失的实际空气制冷机制冷率密度优化

以制冷率密度作为热力性能目标,综合考虑热漏、热阻和循环内不可逆性,对不可逆简单空气制冷机进行分析,导出了制冷率密度和制冷系数解析关系式,对制冷率密度进行了优化,并由数值计算分析了热漏、压比、热导率分配等参数对制冷率密度的影响特点.     

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。     

一类不可逆制冷机的热经济学性能优化

基于导热规律为Q∝△(Tn)时的一类不可逆制冷机的循环模型,以每单位成本的制冷率作为热经济学目标函数,优化制冷机的各种性能参数。导出热经济学目标函数和制冷系数间在不同传热规律下的基本优化关系,研究内不可逆性、热漏和经济参数对制冷机热经济性能的影响。所得结果可对实际制冷机的优化设计提供理论依据。     

不可逆回热式玻色布雷顿制冷循环性能分析

基于玻色气体的热力学性质和回热式布雷顿制冷循环的不可逆模型,导出循环的一些重要性能参数,如循环的制冷量、回热量、输入功和性能系数的一般表达式。通过数值计算获得了循环的一些重要的性能特性曲线,分析了循环的不可逆性和回热特性对玻色布雷顿制冷机性能的影响。     

一类回热式布雷顿制冷循环的有限时间热力学性能

研究了恒温热源条件下具有等熵压缩、膨胀过程的闭式回热式布雷顿制冷循环的有限时间热力学性能。导出循环制冷率、制冷系数与循环压比的关系，由此得到最佳制冷率、制冷系数的特性。     

变温热源不可逆布雷顿制冷循环制冷率密度优化

用有限时间热力学分析方法,制冷率密度为热力学优化目标,分析了变温热源条件下不可逆布雷顿制冷循环的性能,得到了普适的解析关系式,并由数值计算分析了压比、热导率分配以及工质和热源间热容率匹配等参数对制冷率密率的影响特点.     

不可逆布雷顿制冷循环的性能优化

基于不可逆布雷顿制冷循环模型,导出循环制冷率和性能系数之间优化关系所应满足的方程,利用数值解,研究内不可逆性和传热不可逆性对优化性能的影响.讨论了循环的各种优化性能,所得结果对实际制冷系统的优化设计有一定的指导意义.     

内可逆四热源制冷系统的性能分析和优化

在恒温热源条件下内可逆四热源吸收式制冷循环的基础上 ,考虑传热服从线性唯象定律 ,导出了循环的制冷率和制冷系数的基本优化关系和最大制冷率及相应的制冷系数 ;并通过数值计算 ,得出循环参数对循环的制冷率、制冷系数的影响。     

Thermoeconomic optimization of a two stage combined refrigeration system: a finite-time approach

A finite-time thermoeconomic performance analysis based on a new kind of optimization criterion has been carried out for a two-stage endoreversible combined refrigeration cycle model. The optimal performances and design parameters that maximize the objective function (cooling load per total cost) are investigated. In this context, the optimal temperatures of the working fluids, the optimum performance coefficient, the optimum specific cooling load and the optimal distribution of the heat exchanger areas are determined in terms of technical and economical parameters. The effects of the economical parameter that characterizes the investment and energy consumption costs on the general and the optimal performances have been discussed.     

Performance optimization of three-heat-source irreversible refrigerators based on a new thermo-ecological criterion

This paper presents an optimization study of an irreversible refrigeration absorption system based on a new thermo-ecological criterion. The considered objective function is the ecological coefficient of performance (ECOP). It takes into account the first and second law of thermodynamics and is defined as the cooling load per unit loss rate of availability. The ecological coefficient of performance has been expressed and maximized according to the temperatures of the working fluid in the main components of the system. The corresponding optimal temperatures and other optimum performance parameters have been derived analytically, and the effects of the internal irreversibility, the heat leakage coefficient and the source temperature ratio on the global and optimal performances are discussed. The results show that the maximum coefficient of performance (COP) and ecological coefficient of performance (ECOP) occurs for the same operating conditions.     

A new thermoeconomic approach and parametric study of an irreversible regenerative Brayton refrigeration cycle

The detailed parametric study of an irreversible regenerative Brayton refrigerator cycle using the new thermoeconomic approach is presented in this paper. The external irreversibility is due to finite temperature difference between the cycle and the external reservoirs while the internal irreversibilities are due to the nonisentropic compression and expansion processes and the regenerative loss. The thermoeconomic objective function defined as the cooling load per unit cost is optimized with respect to the state point temperatures for a typical set of operating conditions. The power input and cooling load are found to be decreasing functions of the expansion outlet temperature (T₁), while it is the reverse in the case of COP. On the other hand, there are optimal values of the temperature T₁, cooling load, power input and COP at which the cycle attains the maximum objective function for a typical set of operating parameters. Again, the objective function, COP and cooling load further enhance, while the power input goes down, as the various values of the effectiveness or efficiency components are increased.     

Performance characteristics of an irreversible magnetic Brayton refrigeration cycle

Based on the thermodynamic properties of a paramagnetic salt, an irreversible model of the magnetic Brayton refrigeration cycle is established, in which the working substance is a special paramagnetic material. The expressions of the important performance parameters, such as the coefficient of performance, refrigeration load and work input, are derived. Moreover, the optimal performance parameters are obtained at the maximum coefficient of performance. The results obtained here may include the ones of the magnetic Brayton refrigeration cycle using the magnetic material obeyed the Curie law as the working substance, the magnetic Brayton refrigeration cycle without regeneration and the eversible magnetic Brayton refrigeration cycle. Therefore, the results obtained here have general significance and will be helpful to deeply understand the performance of a magnetic Brayton refrigeration cycle.     

费米气体布雷顿制冷循环的性能分析

基于理想费米气体的状态方程，建立以理想费米气体^3He为工质的布雷顿制冷循环模型，导出循环的输入功、制冷系数和制冷量等重要参数的普遍表达式。对几种有趣的情况作了详细的讨论。确定了布雷顿制冷循环正常运行的压强比界限。     

有限热源四温位不可逆吸收式制冷循环模型及性能分析

建立了热源热容量有限、综合考虑热源与环境间的热漏、热源与循环工质问的热阻以及循环内部不可逆性时的不可逆四温位吸收式制冷循环模型，并导出了循环制冷率和制冷系数间的一般关系式；利用数值算例，分析了吸收式制冷机的一般性能和优化性能，得出了热漏、内不可逆性和工质放热量分配率对循环性能的影响规律。所得结论可为吸收式制冷机的设计和优化提供一些新的理论指导。     

送风温度对车用跨临界CO2制冷系统影响的仿真研究

为研究送风温度对实际车用跨临界CO₂制冷系统综合性能的影响,借助GT-Suite仿真软件,建立了单级跨临界CO₂制冷系统的仿真模型。基于设计的三种工况,在风量设置上限的情况下对比了不同送风温度下系统的性能,提出了有效COP_eff的概念并对此进行研究。结果表明：在其他工况相同的条件下,提高送风温度可以提高系统的COP、有效COP_eff以及带风机功耗的有效COP_{eff, b};在低冷负荷工况下,考虑系统风机功耗后的综合性能COP_b存在最优值为3.819,即系统存在对应的最优送风温度,但当负荷增大至一定水平时,最优送风温度不再存在。