碟式斯特林发动机的研究进展

太阳能的利用和斯特林发动机的研发符合目前解决全球能源危机问题的需要。对斯特林热机的发展过程和循环工作原理进行了总结,综述了国内外对于碟式斯特林发电技术的应用现状,归纳了碟式斯特林发电系统中太阳光跟踪控制系统、接收器聚热技术、斯特林发动机功率控制技术和斯特林发动机密封技术等关键技术的研究成果和应用现状,总结并展望了碟式斯特林发电技术的发展重心,为进一步的研究工作提供参考。     

太阳能斯特林发电机性能分析和发展趋势

综述了目前国际上主流的斯特林发电机的研制现状及发展动态,总结了制作斯特林发电机的关键技术,通过比较两类发电机的结构和性能,认为自由活塞式发电机是未来太阳能斯特林发电机领域的主流产品。     

非均质温差发电器的性能分析

建立非均质温差发电器(TEG)理论模型,考虑热电材料的非均质导热系数以及温差发电器与热源间的传热热阻的影响,分析非均质温差发电器的一般性能.讨论热电元件对数、热导率、高温热源温度对非均质温差发电器性能特性的影响.结果表明,相较于均质温差发电器,导热系数不均匀强度越大,非均质温差发电器的最大输出功率和最大效率越高;热电元...     

热电发电器的研究进展

简要介绍了热电发电器的原理、特点、基本结构及其改进措施,总结了近年来国内外在热电发电器件研究方面的现状,最后展望了热电发电器的前景。     

碟式斯特林太阳能发电系统最新进展

太阳能热发电技术中最具发展潜力的是碟式太阳能高温发电技术,尤其是近几年碟式斯特林太阳能发电技术更是令世界瞩目,它具有光电转换效率高、耗水量低、发电方式灵活及可逐步规模化等特点。目前,国内外碟式斯特林太阳能发电系统的研制方兴未艾,国外太阳能斯特林发电机制作及测试技术已趋于成熟,正处于中试和大规模推广阶段。国外主要的碟式斯特林发电系统包括SES公司的SunCatcher单元、Cleanergy公司的Eurodish单元、Infinia公司的PowerDish单元等。国内碟式斯特林太阳能热发电技术研究取得了一些成绩,但总体来说,目前还未获得实质性的进展,相关研究尚处于初级阶段。碟式斯特林太阳能发电系统的核心部件是太阳能斯特林发电机,其某些关键部件的研发难度较大,如高温太阳能吸收器、高效回热器、工质密封、功率和转速控制等。要攻克这些关键技术,需要国内外相关部门的大力支持。我国科研工作者应通过各种形式与国外斯特林发电机制造商及科研机构进行技术合作,逐渐掌握此项技术;或者借鉴国外的研制经验自主研发,然后通过示范推广,建设大型碟式斯特林太阳能发电厂。     

碟式斯特林太阳能热发电的技术发展

碟式斯特林太阳能热发电是目前发电效率最高的太阳能热发电的技术.介绍了碟式斯特林太阳能热发电系统原理,论述了国际上目前以热气机为核心技术的碟式太阳能热发电系统发展状况.指出我国的燃气热气机发电技术已经取得了突破性的发展,25 kW级碟式斯特林太阳能热发电系统的研发已具备了技术基础.     

低温差下半导体温差发电器(火用)分析

半导体温差发电器的性能通常用输出功率和工作效率来进行评价，但在低温差对低品位能的利用上，只用工作效率来评价是不全面的。从[火用]的角度对低温差下半导体温差发电器的工作性能进行了分析，提出了[火用]效率，用炯效率来作为低温差下半导体温差发电器的评价参数。实验结果表明，随着温差的减小，半导体温差发电器的工作效率明显下降，但[火用]效率则基本稳定。     

太阳能驱动半导体温差发电器性能参数的优化设计

应用非平衡态热力学理论,研究太阳能驱动半导体温差发电器的性能特性,确定发电器在最大效率时的优化条件,对系统的主要参数作了详细的讨论,得到一些有意义的新结论。     

不同优化准则下斯特林发动机的性能分析

应用有限时间热力学原理.建立了一个考虑热阻、热漏和回热损失等不可逆因素的斯特林发动机模型;推导了最大输出功率、最大效率和生态学优化准则下,斯特林发动机性能的表达式;比较了三种优化准则下,热漏系数和回热器有效性对斯特林发动机性能的影响.研究表明:对热漏损失和回热损失较大的斯特林发动机,宜选用生态学优化准则.为斯特林发动机...     

车用内置式温差发电器换热性能的数值模拟

本文针对提出的一种内置高强度温差发电器的结构,采用FLUENT软件对其对流换热系数、速度模量、径向速度进行分析,并和平板式温差发电器进行对比.结果表明提出的新结构在壁面换热方面优于平板式温差发电器,在节能应用中有很大潜力.     

A space power system of free piston Stirling generator based on potassium heat pipe

The power system of a free piston Stirling generator (FPSG) based on potassium heat pipes has been developed in this paper. Thanks to the advantages of long life, high reliability, and high overall thermal efficiency, the FPSG is a promising candidate for nuclear energy, especially in space exploration. In this paper, the recent progress of FPSG based on nuclear reactor for space use was briefly reviewed. A novel FPSG weighted only 4.2 kg was designed, and one dimensional thermodynamic modeling of the FPSG using Sage software was performed to estimate its performance. The experiment results indicated that this FPSG could provide 142.4 W at a thermal-to-electric efficiency of nearly 17.4%. Besides, the power system integrated with four FPSGs and potassium heat pipes was performed and the single machine failure test was conducted. The results show that this system could provide an electrical power of 300 W at an overall thermal efficiency of 7.3%. Thus, it is concluded that this power system is feasible and will have a great prospect for future applications.     

分置式斯特林发动机热力性能的仿真

对斯特林发动机的压缩与膨胀过程进行了变质量系统热力学分析。利用等温模型分析法,引入流动阻力损失的计算模型,模拟了分置式斯特林发动机内部工质的压力等参数的动态变化规律。仿真结果表明：斯特林发动机在运行过程中压缩腔与膨胀腔的气体压力并不时时相等;提高发动机的转速和高温热源温度,可以增加发动机的输出功率。     

Thermal model of a dish/Stirling systems

This paper presents a global thermal model of the energy conversion of the 10 kW_el Eurodish dish/Stirling unit erected at the CNRS-PROMES laboratory in Odeillo. Using optical measurements made by DLR, the losses by parabola reflectivity and spillage are calculated. A nodal method is used to calculate the heat losses in the cavity by conduction, convection, reflection and thermal radiation. A thermodynamic analysis of a SOLO Stirling 161 engine is made. The Stirling engine is divided in 32 control-volumes and equations of ideal gas, mass and energy conservation are written for each control-volume. The differential equation system is resolved by an iterative method developed using Matlab^™ programming environment. Temperature, mass, density of working gas, heat transfers and the mechanical power are calculated for one Stirling engine cycle of 40 ms and for a constant direct normal irradiation (DNI). The model gives consistent results correctly fitting with experimental measurements.     

Mobile hydraulic power supply: Liquid piston Stirling engine pump

Conventional mobile hydraulic power supplies involve numerous kinematic connections and are limited by the efficiency, noise, and emissions of internal combustion engines. The Stirling cycle possesses numerous benefits such as the ability to operate from any heat source, quiet operation, and high theoretical efficiency. The Stirling engine has seen limited success due to poor heat transfer in the working chambers, difficulty sealing low-molecular weight gases at high pressure, and non-ideal piston displacement profiles. As a solution to these limitations, a liquid piston Stirling engine pump is proposed. The liquid pistons conform to irregular volumes, allowing increased heat transfer through geometry features on the interior of the working chambers. Creating near-isothermal operation eliminates the costly external heat exchangers and increases the engine efficiency through decreasing the engine dead space. The liquid pistons provide a positive gas seal and thermal transport to the working chambers. Controlling the flow of the liquid pistons with valves enables matching the ideal Stirling cycle and creates a direct hydraulic power supply. Using liquid hydrogen as a fuel source allows cooling the compression side of the engine before expanded the fuel into a gas and combusting it to heat the expansion side of the engine. Cooling the compression side not only increases the engine power, but also significantly increases the potential thermal efficiency of the engine. A high efficiency Stirling engine makes energy regeneration through reversing the Stirling cycle practical. When used for regeneration, the captured energy can be stored in thermal batteries, such as a molten salt. The liquid piston Stirling engine pump requires further research in numerous areas such as understanding the behavior of the liquid pistons, modeling and optimization of a full engine pump, and careful selection of materials for the extreme operating temperatures. Addressing these obtainable research quandaries will enable a transformative Stirling engine pump with the potential to excel in numerous applications.     

Coupling a Stirling engine with a fluidized bed combustor for biomass

The paper deals with the integration between a kinematic Stirling engine and a fluidized bed combustor for micro-scale cogeneration of renewable energy. A pilot-scale facility integrating a 40 kW_t combustor and a γ-type Stirling engine (0.5 kW_e) was set up and tested to demonstrate the feasibility of this solution. The Stirling engine was installed at a lateral wall of the combustor in direct contact with the fluidized bed region. An experimental campaign was executed to assess the performance of the innovative integrated system. The experimental results can be summarized in: (a) very high combustion efficiency with biomass feeding, (b) elevated heat transfer rate to the engine, (c) a relatively small share (about 2 kW_t) transferred to the engine from the thermal power generated by the combustor (around 13 kW_t), (d) conversion to electric power close to the upper limit of the engine, (e) limited impact of the Stirling engine on the fluidized bed behavior, for example, temperature. From the analysis of measured variables, the dynamics is dominated by the fast response of the Stirling engine, which rapidly reacts to the slow changes of the fluidized bed combustor regime: the dynamic response of the tested facility as a thermal system was slow, the time constant being of the order of 10 minutes.     

基于斯特林发动机的低温等离子体净化汽车尾气技术

随着汽车的大量普及,汽车尾气已成为亟待解决的问题。斯特林发动机技术和低温等离子体技术在各自领域均有无可替代的优势,将两种技术结合可以产生广泛的应用。基于斯特林发动机的低温等离子体净化汽车尾气技术可以利用汽车尾气余热处理汽车尾气中污染物,具有节能、高效、低成本的显著优势。     

Development of a beta-type Stirling heat pump with rhombic drive mechanism by a modified non-ideal adiabatic model

In this paper, a thermodynamic model is developed for predicting the performance of a beta-type Stirling heat pump with rhombic drive mechanism for water heater and the model is validated by a 1-kW class prototype Stirling heat pump. In the present model, the working space is divided into expansion space, heat absorber, regenerator, heat rejecter and compression space. The pressure, mass and temperature variations of working fluid in each working space are predicted. The temperature variation of wall boundary is also taken into consideration. The temperature of working fluid in each working space and the temperature of wall boundary are obtained by solving energy equations simultaneously. Eventually, the pressure of working fluid in each working space can be corrected by using empirical formula of pressure drop. All the thermal properties of working fluid and wall boundary in each working space at each time step can be obtained by repeating the above process. Then, the performance of heat pump such as absorbing heat, rejecting heat, indicated power and COP can be calculated. A series of experimental measurements and comparisons are also conducted for validating present model. The results show that the prototype heat pump can produce 904 W heating power and 38°C hot water under 1 LPM water flow rate with 5 bar helium at 1000 rpm.     

Investigation on power output of the gamma-configuration low temperature differential Stirling engines

This paper provides a study on power output determination of a gamma-configuration, low temperature differential Stirling engine. The former works on the calculation of Stirling engine power output are discussed. Results from this study indicate that the mean pressure power formula is most appropriate for the calculation of a gamma-configuration, low temperature differential Stirling engine power output.