A Review of Recent Trends in Quantum Thermodynamics and a System’s Behavioural Analysis of the Universe Originating as a Quantum Energy System

This paper combines a review of recent advances in quantum thermodynamics, including work on objective collapse (Zurek’s quantum Darwinism) and quantum gravity (Verlinde’s quantum gravity explanation), with a redefinition of entropy generation as systems’ change process. These concepts are used as systems’ behaviour analysis tools to allow us to revisit Hartle and Hawking’s 1983 quantum universe and develop a hypothesis for how physically a universe starting in a quantum state could evolve into our current universe, based on systems analysis. The outcome of this analysis raises a question: do we already have the elements of a “theory of everything” hiding in plain sight within recent advances in quantum thermodynamics?

Thermodynamic Analysis of a Condensate Heating System from a Marine Steam Propulsion Plant with Steam Reheating

The thermodynamic(energy and exergy)analysis of a condensate heating system,its segments,and components from a marine steam propulsion plant with steam reheating is performed in this paper.It is found that energy analysis of any condensate heating system should be avoided because it is highly influenced by the measuring equipment accuracy and precision.All the components from the observed marine condensate heating system have energy destructions lower than 3 kW,while the energy efficiencies of this system are higher than 99%.The exergy efficiency of closed condensate heaters continuously increases from the lowest to the highest steam pressures(from 70.10%to 92.29%).The ambient temperature variation between 5℃and 45℃notably influences the exergy efficiency change of both low pressure heaters and the low pressure segment equal to 31.61%,12.37%,and 18.35%,respectively.

Thermodynamic analysis and combined cycle research on recoverable pressure energy in natural gas pipeline

Current research and ways of capturing mechanical energy are discussed in this paper. By the aid of the comprehensive thermodynamic analysis and Aspen simulation tool, the amount of a vailable work that can be produced from capturing the pressure energy has been calculated. Based on the comprehensive thermodynamic analysis, two systems have been proposed to capture pressure energy of natural gas to generate electricity. In this study, the expression of exergy is given which can be used in evaluating purposes. A problem with this multidisciplinary study is the complicated boundary condition. In conclusion, a technical prospect on recoverable natural gas pressure energy has been presented based on total energy system theory.

A New Tri-Generation System： Thermodynamical Analysis of a Micro Compressed Air Energy Storage

There is a growing interest in the electrical energy storage system, especially for matching intermittent sources of renewable energy with customers＇ demand. Furthermore, it is possible, with these system, to level the absorption peak of the electric network （peak shaving） and the advantage of separating the production phase from the exertion phase （time shift）. CAES （compressed air energy storage systems） are one of the most promising technologies of this field, because they are characterized by a high reliability, low environmental impact and a remarkable energy density. The main disadvantage of big systems is that they depend on geological formations which are necessary to the storage. The micro-CAES system, with a rigid storage vessel, guarantees a high portability of the system and a higher adaptability even with distributed or stand-alone energy productions. This article carries out a thermodynamical and energy analysis of the micro-CAES system, as a result of the mathematical model created in a Matlab/Simulink environment. New ideas will be discussed, as the one concerning the quasi-isothermal compression/expansion, through the exertion of a biphasic mixture, that will increase the total system efficiency and enable a combined production of electric, thermal and refrigeration energies. The exergy analysis of the results provided by the simulation of the model reports that more than one third of the exergy input to the system is lost. This is something promising for the development of an experimental device.

Advanced exergy analysis of the turbojet engine main components considering mexogenous, endogenous, exegenous, avoidable and unavoidable exergy destructions

In this study, exergy dynamic and advanced exergy analyses are applied to theturbojet engine to assess its mexogenous, endogenous, exogenous, avoidable and unavoidableexergies under the environment conditions of 15
C temperature and 1 bar pressure. Themaximum exergy point in the turbojet engine is found for the combustor in which C11H23(Jet-A1) fuel is combusted with air, while the minimum one is determined for the aircompressor head where the free air enters. The combustion chamber has the maximum fuel,product and irreversibility rates and the air compressor has the minimum fuel and product ex-ergy values, while the minimum irreversibility is found for the turbine. Maximum improvementpotential rate is found for the combustion chamber (5141.27 kW), while minimum rate is deter-mined for the turbine of system (6.95 kW). Also, the turbine component has the highest exergyefficiency (97.20%) due to its expansion process, while combustion chamber component hasthe lowest exergy efficiency (55.39%) due to low efficient combustion process of the fuel.Furthermore, the mexogenous exergy destructions from maximum to minimum are found for the combustion chamber, air compressor and gas turbine units, respectively. Considering exergydynamic analysis, the mexogenous exergy destruction rates of the combustion chamber, aircompressor and gas turbine are found as 184.4 kW, 103.97 kW and 9.99 kW, respectively.Considering all results, the combustion chamber is the primer component to be handled for bet-ter efficiency and improvement.

Exergy Analysis of a Solar Vapor Compression Refrigeration System Using R1234ze(E)as an Environmentally Friendly Replacement of R134a

Refrigeration plays a significant role across various aspects of human life and consumes substantial amounts of electrical energy.The rapid advancement of green cooling technology presents numerous solar-powered refrigeration systems as viable alternatives to traditional refrigeration equipment.Exergy analysis is a key in identifying actual thermodynamic losses and improving the environmental and economic efficiency of refrigeration systems.In this study exergy analyze has been conducted for a solar-powered vapor compression refrigeration(SP-VCR)system in the region of Gharda颽(Southern Algeria)utilizing R1234ze(E)fluid as an eco-friendly substitute for R134a refrigerant.A MATLAB-based numerical model was developed to evaluate losses in different system components and the exergy efficiency of the SP-VCR system.Furthermore,a parametric study was carriedout to analyze the impact of various operating conditions on the system’s exergy destruction and efficiency.The obtained results revealed that,for both refrigerants,the compressor exhibited the highest exergy destruction,followed by the condenser,expansion valve,and evaporator.However,the system using R1234ze(E)demonstrated lower irreversibility compared to that using R134a refrigerant.The improvements made with R1234ze are 71.95%for the compressor,39.13%for the condenser,15.38%for the expansion valve,5%for the evaporator,and 54.76%for the overall system,which confirm the potential of R1234ze(E)as a promising alternative to R134a for cooling applications.

An effective thermodynamic transformation analysis method for actual irreversible cycle

An effective thermodynamic transformation analysis method was proposed in this study. According to the phenomenon of ex- ergy consumption always coupling with heat transfer process, the effective thermodynamic temperatures were defined, then the actual power cycle or refrigeration/heat pump cycle was transformed into the equivalent reversible Carnot or reverse Carnot cycles for thermodynamic analysis. The derived effective thermodynamic temperature of the hot reservoir of the equivalent reverse Camot cycle is the basis of the proposed method. The combined diagram of TR-h and TR-q was adopted for the analy- sis of the system performance and the exergy consumption, which takes advantage of the visual expression of the heat/work exchange and the enthalpy change, and is convenient for the calculation of the coefficient of performance and exergy con- sumptions. Take a heat pump water heater with refrigerant of R22 for example, the proposed method was systematically intro- duced, and the fitting formulas of the effective thermodynamic temperatures were given as demonstration. The results show that the proposed method has advantage and well application foreground in the performance simulation and estimation under the variable working conditions.

Multi-objective evolutionary optimization and thermodynamics performance assessment of a novel time-dependent solar Li-Br absorption refrigeration cycle

This research paper aims to perform dynamics analysis,3E assessment including energy,exergy,exergoeconomic,and the multiobjective evolutionary optimization on a novel solar Li-Br absorption refrigeration cycle.The research is time-dependent,owing to solar radiation variability during different timelines.Theoretically,all the necessary thermodynamic,energy,and exergy equations are applied initially.This is followed by the thermoeconomic analysis,which takes place after defining the designing variables during the thermoeconomic optimization process and is presented together with the economic relations of the system and its thermoeconomic characteristics.Furthermore,the sensitivity analysis is undertaken,the source of system inefficiency is determined,the multi-objective evolutionary optimization of the whole system is carried out,and the optimal values are compared with the primary stage.Engineering Equation Solver(EES)software has been used to accomplish comprehensive analyses.As part of the validation process,the results of the research are compared with those published previously and are found to be relatively consistent.

Exergy Analysis of Photo-Thermal Interaction Process between Solar Radiation Energy and Solar Receiver

A unified theory of non-equilibrium radiation thermodynamics is always in search as it is meaningful for solar energy utilization.An exergy analysis of photo-thermal interaction process between the solar radiation energy and solar receiver is conducted in this paper.The non-equilibrium radiation thermodynamic system is described.The thermodynamic process of photo-thermal interaction between the solar radiation and solar receiver is introduced.Energy,exergy and entropy equations for the photo-thermal process are provided.Formulas for calculating the optimum receiving temperatures of the solar receiver under both non-concentration and solar concentration conditions are presented.A simple solar receiver is chosen as the calculation example to launch the exergy analysis under non-concentration condition.Furthermore,the effect analysis of solar concentration on the thermodynamic performance of the solar receiver for solar thermal utilization is carried out.The analysis results demonstrate that both the output exergy flux and efficiency of the solar receiver can be improved by increasing the solar concentration ratio during the solar thermal utilization process.The formulas and results provided in this paper may be used as a theoretical reference for the further studies of non-equilibrium radiation thermodynamic theory and solar thermal utilization.

Finite time thermodynamic analysis and optimization of water cooled multi-spilit heat pipe system(MSHPS)

This study focuses on the heat transfer characteristics of the evaporation terminal,the cool distribute unit(CDU)and refrigerant flow distribution of a water cooled multi-spilit heat pipe system(MSHPS)used in data center.The finite time thermodynamic analysis,the exergy method and the software SIMULINK was employed to build the simulation model of the combined system.The results show that the IT servers should concentrate on arranging at the location below 1.3 m.The CDU has a heat transfer of about 74 J in a period of 6 s.And the optimum flow rate of the CDU is 0.82 kg/s.The flow distribution characteristic of a CDU which connect 2 heat pipe evaporator terminals of 6 kW was calculated,and the working fluid is R22.Then the free cooling time,part time free cooling and energy saving potential in major cities of China were analysised.The energy saving potential is from 61%to 25%.The results are of great significance for the operational control and practical application of a MSHPS and other pipe-net systems.

Comprehensive performance analysis and optimization of 1,3-dimethylimidazolylium dimethylphosphate-water binary mixture for a single effect absorption refrigeration system

The energy and exergy analyses of the absorption refrigeration system (ARS) using H2O-[mmim][DMP] mixture were investigated for a wide range of temperature. The equilibrium Dühring (P-T-XIL) and enthalpy (h-T-XIL) of mixture were assessed using the excess Gibbs free non-random two liquid (NRTL) model for a temperature range ??? of 20°C to 140°C and XIL from 0.1 to 0.9. The performance validation of the ARS cycle showed a better coefficient of performance (COP) of 0.834 for H2O-[mmim][DMP] in comparison to NH3-H2O, H2O-LiBr, H2O-[emim][DMP], and H2O-[emim][BF4]. Further, ARS performances with various operating temperatures of the absorber (Ta), condenser (Tc), generator (Tg), and evaporator (Te) were simulated and optimized for a maximum COP and exergetic COP (ECOP). The effects of Tg from 50°C to 150°C and Ta and Tc from 30°C to 50°C on COP and ECOP, the Xa, Xg, and circulation ratio (CR) of the ARS were evaluated and optimized for Te from 5°C to 15°C. The optimization revealed that Tg needed to achieve a maximum COP which was more than that for a maximum ECOP. Therefore, this investigation provides criteria to select low grade heat source temperature. Most of the series flow of the cases of cooling water from the condenser to the absorber was found to be better than the absorber to the condenser.

液-液二氧化碳储能系统的性能分析

随着间歇性可再生能源的普及,储能系统在电网中发挥着关键作用。与空气储能系统相比,二氧化碳储能具有储能密度高、易液化、环境友好等优势。首先建立了一种液-液二氧化碳储能系统,然后利用Aspen Plus仿真软件对其储能过程进行建模分析,揭示了储能压力、释能压力、压缩机进口压力、节流阀压降、压缩机效率及膨胀机效率等参数变化对系统性能的影响。最后,对这种液-液二氧化碳储能系统进行了参数分析,得到系统最优工艺参数。同时对系统进行[火用]分析,得到[火用]损分布,分析讨论了系统产生[火用]损的内部原因。

危废焚烧锅炉饱和蒸汽驱动有机朗肯循环系统热力学分析

危险废弃物焚烧处理过程中产生的热量通常用于生产饱和蒸汽以供应工业园区的蒸汽、热量等需求,也可以用于低温发电。分析了饱和蒸汽驱动有机朗肯循环(ORC)系统做功时的热力学特性。通过基本工况下蒸汽潜热型热源与ORC系统的热匹配特性分析,提出3种优化措施,并研究了单一优化和组合优化措施下以及不同工况下的系统热力学性能。结果表明,组合优化可使系统获得更优的性能,相对于基本工况,优化后的工况下最大净输出功为3 193.81 kW,提高了170.46%;热效率为23.34%,提高了30.25%;总[火用]效率为66.25%,提高了41.80%。

面向工程应用的先进绝热压缩空气储能模型及先进㶲分析

先进绝热压缩空气储能(advanced adiabatic compressed air energy storage system,AA-CAES)仿真建模及分析是其工程实践的基础。然而,目前模型一般基于理想工况建立,分析结果与实际工况相偏差较大,无法指导工程应用。为此,在传统热力学模型基础上,考虑了空气流动阻力损失和能量转换设备损耗等因素,建立了面向工程应用的AA-CAES模型并以200MW盐穴AA-CAES系统为例进行了分析。同时,对系统效率分析方法进行改进并对其进行了先进㶲分析。结果表明,空气管道㶲损失占总㶲损失比例接近7%,能量转换设备损耗导致电-电效率比轴功效率低5%,二者对系统性能影响较大,在进行工程设计时不可以忽略。系统各部件可避免㶲损失占比均较大,表明系统具有较大的性能提升潜力。各部件㶲损失为其内部㶲损失,与其他部件是否工作在最佳状态关系不大。

集成LNG冷能空分的半闭式CO_(2)循环发电系统热力学分析与优化

半闭式CO_(2)循环具有高效和零碳排放的特点,针对目前集成液化天然气(LNG)冷能的半闭式CO_(2)循环发电系统,提出了一种高效的LNG冷能的梯级利用方式。结果表明:基准案例中空分和压缩过程的能耗分别降低了70.4和75 MW,系统净效率为63.76%,相比于常规循环提升9.48个百分点;在此基础上,采取改进循环参数、匹配回热器热容等优化措施后,优化案例的净效率进一步提高至72.22%,系统的效率为51.27%。相比于仅在循环过程集成LNG冷能的参考系统Ⅱ,冷能利用的效率提高了28个百分点。

氦低温系统关键参数及流程优化研究进展

氦低温系统应用于极低温技术领域,高效节能的氦低温系统将极大推动低温超导技术的发展。因此,研究系统中主要部件对其性能的影响、针对系统中主要热力学参数进行遗传算法优化,对提高系统制冷效率和经济效益以及保持其长期运行的稳定性十分重要。基于此,对国内外氦低温系统主要影响部件膨胀机和换热器的关键参数以及[火用]分析和遗传算法优化进行了梳理分析,总结了现存技术难点和发展趋势。

超临界-超临界二氧化碳储能系统的性能分析

随着间歇性可再生能源的普及,储能系统在电网中发挥着关键作用。与空气储能系统相比,二氧化碳储能具有储能密度高、易液化、环境友好等优势。首先建立了一种超临界-超临界二氧化碳储能系统,然后利用Aspen Plus软件对其储能过程进行建模分析,揭示了储能压力、释能压力、加热器加热温度、节流阀压降、压缩机效率、膨胀机效率等参数变化对系统性能的影响。最后,对二氧化碳储能系统进行参数分析,得到系统最优工艺参数。同时对系统进行[火用]分析,得到[火用]损分布,并分析讨论了系统产生[火用]损的内部原因。

工质R245fa、R1233zd(E)对有机朗肯循环系统热力学性能的影响

为了研究传统工质R245fa和低全球变暖潜能值工质R1233zd(E)在回热式有机朗肯循环(organic Rankine cycle,ORC)系统中的热力学性能,使用工程方程求解器(engineering equation solver,EES)软件建立采用2种工质的系统热力学模型,分析不同运行参数下系统热效率和[火用]效率。结果表明:与采用R245fa为工质相比,采用R1233zd(E)的系统热效率提高了12.85%,[火用]效率提高了27.42%;通过调整蒸发器的过热度和冷凝器的过冷度,可以进一步提高系统的热力学性能。

Highview Power液化空气储能中试装置热力学分析

[目的]构建以新能源为主体的新型电力系统,储能成为必不可少的支撑技术。液化空气储能是一种新兴的技术经济可行的大规模储能解决方案,具有广泛的应用前景。Highview Power液化空气储能中试装置是目前唯一公开了现场测试数据的液化空气储能系统。为探究液化空气储能的热力学原理,寻求提升循环效率的方法。[方法]根据Highview Power液化空气储能中试装置的工艺流程建立了热力学建模,利用测试数据验证了热力学模型的准确性。通过?分析研究制约循环效率的关键设备,通过控制变量法研究关键操作参数对储能过程和释能过程的影响。[结果]结果表明:制约循环效率的关键设备是循环压缩机和汽化器;增加高压压力和节流后压力、提高增压膨胀机的分流质量和入口温度、回收释能过程回热器的冷量有利于提升储能过程液化率、降低液化能耗;提高释能高压压力和膨胀机组入口温度有助于提升系统的输出功率和循环效率。[结论]提出了回收压缩热、提高压缩机等熵效率、减小汽化器换热温差等改进措施以提升循环效率。

水冷多联管热管系统的有限时间热力学分析与优化

采用有限时间热力学、㶲方法分析了水冷多联热管系统(MSHPS)。计算结果表明,IT服务器应该集中安排在1.3m以下的位置。CDU在6s的时间内具有约74J的传热量。最佳流量时CDU的速率为0.82kg/s。计算了免费冷却时间,部分免费冷却时间。并分析了中国主要城市的节能潜力从61%到25%。研究结果对其他管网系统实际应用具有重要意义。