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91.
基于理想气体与蓄冷器的假设,运用热力学第一、二定律对蓄冷器进行热力学分析,研究工质温度在蓄冷器单元内的变化,以及脉管制冷机运行频率对工质温度的影响,并运用Matlab软件,对蓄冷器单元内温度进行模拟。研究表明:对于理想蓄冷器,同等压力波幅下,增大频率和蓄冷器空体积,都会增大气体的温度波动幅值。 相似文献
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传统的斯特林制冷机回热器使用接触式滑动密封,存在磨损,限制斯特林制冷机的使用寿命。间隙密封的应用则可以在完成密封作用的同时消除接触磨损和因此而产生的污染。但由于间隙内气体的泄漏,引起了冷量损失,使制冷量减少。设计了一套模拟实验装置,通过实验验证了回热器与气缸壁间隙内气体泄漏率及泄漏引起的冷量损失理论分析的正确性。 相似文献
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Thermoacoustic oscillation is a significant problem in ducted domestic heating systems fitted with fully premixing burners as well as in combustion systems of industrial scale. This paper reports experiments using a burner closely representative of practical designs in which high-intensity free-field sound has been used to simulate the feedback which may be excited naturally in installations with different acoustic properties. This experimental approach facilitates study of the non-linear response of the burner/flame sub-system to feedback of different frequencies and direct measurement of the acoustic impedance of the burner under operational conditions. A function proportional to the Rayleigh integral has been evaluated directly from the experimental results. It is found that the head of this type of burner divides the typical installation into a quarter-wave tube and a Helmholtz resonator which must couple unstably for thermoacoustic oscillations to be autoexciting. It is further found that there is a strong interaction between the acoustic field and the mean flow which modifies significantly the behaviour of the burner as a Helmholtz resonator and thus the stability of the whole system. 相似文献
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An entangled quantum refrigerator working with a three-qubit one-dimensional isotropic Heisenberg XX model in a constant external magnetic field is constructed in this paper. Based on the quantum first law of thermodynamics, the expressions for several basic thermodynamic quantities such as the heat transferred, the net work and the coefficient of performance are derived. Moreover, the influence of the thermal entanglement on the basic thermodynamic
quantities is investigated. Several interesting features of the variation of the basic thermodynamic quantities with the thermal entanglement in zero and nonzero magnetic field are obtained. 相似文献