微型燃气轮机热电联供系统的热经济学最优化分析

以最小燃料费率和非能量费率为目标函数，以系统的热力学模型和经济学模型为约束条件，对3种微型燃气轮机热电联供系统进行了热经济学最优化分析．计算得到的优化参数，可为能量系统的优化设计和运行提供决策参考依据．     

新型太阳能热泵多功能复合机原理与热力学分析

介绍了三热源热泵空调-热水器多功能复合机组成及其工作原理，对系统全面进行了热力学分析，对该系统的空气、太阳能和辅助燃气三热源进行了优化配置，使其具有更佳的性能系数，迎合了普遍关注的新能源利用、能源消费与环境保护的倡导。     

双级耦合热泵供暖系统有限时间热力学性能优化

利用有限时间热力学分析理论，对新型双级耦合热泵供暖系统建立了存在热阻、热漏、内不可逆损失的恒温定常流热力学循环模型，得到系统供热性能最优结果下，最佳传热面积分配，最佳工质工作温度，最小总传热面积以及最小输入功率的解析式．结合实际算例的计算结果，详细分析了各不可逆因素对系统性能的影响．所得结论为新系统在实际推广过程中的设计、运行提供了一定理论依据．     

Q∝(△Tn)时不可逆卡诺制冷机的生态学性能优化

利用有限时间热力学理论，综合考虑热阻、热漏及其他内不可逆性，研究传热规律服从Q∝(△T^n)时不可逆制冷机的生态学优化性能，并由数值算例对不同损失、不同传热规律情况下的卡诺制冷机性能变化规律进行了比较。     

三热源内可逆热变换器比供热率优化

针对经典热力学分析方法的不足,根据热变换器的功能,投资等方面的特点,按照内可逆联合诺循环模型,利用有限时间热力学理论方法,导出了吸收式热变换器比供热率与操作参数,比供热率与热学性能系数的优化关系,从而使优化结果兼顾了系统有能的合理性和与总传热面积相关的反映设备投资回报的经济性指标,对实际热变换器的优化和设计有更全面的指导意义。     

户式中央空调的选择与设计

分析了影响户式中央空调发展的因素,详细介绍了各种户式中央空调的形式及其特点,给出了户式中央空调系统的设计步骤。     

LaF3-NaF体系的热力学优化

运用新改进的用于短程有序体系的对近似似化学模型对LaF3-NaF体系进行了优化，并运用CALPHAD技术对相图进行了计算．改进的似化学模型用来描述体系的吉布斯自由能．借助计算机辅助分析。计算得出一些热力学函数．计算的相图和热力学参数是热力学自恰一致的．     

户式中央空调的特点和发展思路

本文在介绍户式中央空调的特点基础上,提出了发展户式中央空调的思路。户式中央空调系统具有节约能耗、空调品质高、运行维护简单等突出优点,已获得越来越广泛的应用。     

户式中央空调设计和节能的分析探讨

结合市场调查情况和设计体会,对几种常见的户式中央空调系统的工程造价进行了对比,指出了户式中央空调在设计和节能方面存在的问题,并就这些问题给出了一些相应的解决建议。     

太阳能热泵的有限时间热力学分析

基于内可逆三热源热泵的有限时间热力学理论和太阳能集热器的线性热损模型，研究太阳能热泵系统的优化性能，导出太阳能集热器的最佳工作温度、系统的最大总性能系数和最大泵热率，并指出现有文献中有关这类研究的错误，所得结果可为实际太阳能热泵系统的优化设计提供一些新的理论依据。     

空气制冷循环最优性能解析

通过建立单级空气制冷循环的量纲为一的热力学模型,推导出对应最优性能系数的压比公式,以及最优压比下的循环性能参数解析表达式.在此基础上针对不同的运行工况和转动部件效率,对循环性能进行数值分析,发现:高低温热源温差的增大,最优压比升高,最优性能系数下降,单位制冷量升高.提高转动部件效率,最优压比小幅降低,最优性能系数大幅升高以及单位制冷量大幅下降.同比之下,膨胀机效率对系统最优性能的影响更大.这些都有助于实际空气制冷系统的优化设计.     

Variation and optimization of acid-dissolved aluminum content in stainless steel

As a key step in secondary refining, the deoxidation process in clean stainless steel production is widely researched by many scholars. In this study, vacuum oxygen decarburization (VOD) deoxidation refining in a 40-t electric arc furnace + VOD + ingot casting process was analyzed and optimized on the basis of Al deoxidation of stainless steel and thermodynamic equilibrium reactions between the slag and steel. Under good stirring conditions in VOD, the deoxidation reaction reaches equilibrium rapidly, and the oxygen activity in the bulk steel is controlled by the slag composition and Al content. A basicity of 3–5 and an Al content greater than 0.015wt% in the melt resulted in an oxygen content less than 0.0006wt%. In addition, the dissolved oxygen content decreased slightly when the Al content in the steel was greater than 0.02wt%. Because of the equilibrium of the Si–O reaction between the slag and steel, the activity of SiO₂ will increase while the Si content increases; thus, the Si content should be lowered to enable the formation of a high-basicity slag. A high-basicity, low-Al₂O₃ slag and an increased Si content will reduce the Al consumption caused by SiO₂ reduction.     

环形流道内对流换热过程的热力学分析及优化

利用热力学第二定律对管壁热流恒定时环形流道内充分发展区层流对流换热过程进行研究,得到了熵产的一般表达式,讨论了流体温升、换热强度及流动压降对熵产的影响;同时,从减小熵产的角度出发,对流道进行了优化计算。     

Constructal entransy dissipation rate minimization for heat conduction based on a tapered element

Based on constructal theory,the structure of a tapered element and high-conductivity link is optimized by taking the minimization of the entransy dissipation rate as the optimization objective.The results show that the mean temperature difference of the heat transfer cannot always decrease when the internal complexity of the control-volume increases.There exists an optimal constructal order leading to the minimum mean temperature difference for heat transfer.The thermal current density in high-conductivity links with variable shapes does not linearly depend on the length.Therefore,the optimized constructs based on the minimization of the entransy dissipation rate are different from those based on the minimization of the maximum temperature difference.Compared with the construct based on the minimization of the maximum temperature difference,the construct based on the minimization of the entransy dissipation rate can reduce the mean temperature difference,and improve the heat transfer performance significantly.Because entransy describes the heat transfer ability more suitably,various constructal problems in heat conduction may be addressed more effectively using this basis.     

文23储气库增压系统性能模拟及优化研究

文23储气库是目前中国已投运的最大储气库之一，主要负责华北地区市场季节调峰和应急供气任务。以文23储气库注气增压系统为研究对象，以实现增压系统节能降耗和提高工艺水平为目标，建立了增压系统往复式压缩机性能模拟计算模型，并利用Java语言开发了相应的模拟计算程序。在此基础之上，针对增压系统所采用的3种厂家压缩机设备，分别开展了相同工况下各厂家压缩机性能对比模拟计算和工况参数变化对压缩机性能影响模拟计算。模拟计算发现，相同工况下厂家A压缩机具有最高的容积流量和单位能耗。此外，在参数变化对压缩机性能影响方面，一级进气压力升高1 MPa将导致单位能耗降低75 ${\rm {kW \cdot h}}$/(${\times 10^4} {{\rm {Nm}}^3}$)，末级排气压力升高1 MPa将导致单位能耗升高17 ${\rm {kW \cdot h}}$/(${\times 10^4} {{\rm {Nm}}^3}$)，一级和二级进气温度的升高则都将导致单位能耗的小幅度升高。根据模拟分析结果提出了相应的压缩机开机方案优化措施和压缩机工况参数优化措施。研究充分结合了文23储气库增压系统的实际运行特点，所获得的研究结果对储气库现场运行工艺具有重要的指导意义。     

热力学数学研究初探

本文从微分学和代数出发,提出并证明了热力学偏导数,循环公式、热力学空间变换的个数公式及循环公式的一般形式,提出并证明了热力学空间变换,首次实现了热力学公式的计算机证明,为热力学数学研究奠定了基础。     

Constructal optimization on T-shaped cavity based on entransy dissipation minimization

The entransy dissipation extremum principle provides new warranty and criterion for optimization of heat transfer. For a heat transfer model of a rectangular solid wall with an open T-shaped cavity, a dimensionless equivalent thermal resistance based on entransy dissipation is taken as optimization objective, and constructal optimization for the model is carried out when the system volume, the cavity volume and the volume of rectangle occupied by T-shaped cavity are fixed. Numerical results indicate that the optimal geometry construct of cavity can be schemed out based on entransy dissipation extremum principle. The formulation of dimensionless global （maximum） thermal resistance presented in a literature is modified; some new rules which are different from those reported in the literature are obtained based on the minimization of the modified objective. Comparisons of the numerical results show that the optimal system constructs deduced respectively from the two thermal resistance objectives are very different. The optimization by taking equivalent thermal resistance minimization as objective can more effectively reduce mean temperature difference of heat transfer than the optimization by taking maximum thermal resistance minimization as objective, so that the performance of heat transfer for the total system can be improved. The more freedom the cavity has, the better the total system performance is. The correlations of the equivalent thermal resistance and the maximum thermal resistance of the system and three geometric degrees of freedom are found by using function fitting.     

等焓节流的快速迭代法

本文介绍了等焓节流过程的数学模型.推导出在解等焓节流问题时求泡点温度和露点温度的简便公式,大大加速了对等焓节流过程的计算.