自由活塞斯特林发动机作为一种高效的能源转换装置,在可再生能源利用等领域有重要的应用前景。本文针对一种双作用自由活塞型斯特林发电系统,从声电耦合原理出发,推导了双作用斯特林发动机与直线电机之间的阻抗匹配方程,建立了发电系统...自由活塞斯特林发动机作为一种高效的能源转换装置,在可再生能源利用等领域有重要的应用前景。本文针对一种双作用自由活塞型斯特林发电系统,从声电耦合原理出发,推导了双作用斯特林发动机与直线电机之间的阻抗匹配方程,建立了发电系统的整机数值模型,并获得了加热温度、平均压力、活塞连杆直径、机械阻尼和间隙密封宽度等参数对整机性能的影响规律。结果表明,由于双作用活塞两侧同时存在较大的温差和压差,因此相较于单作用结构的系统而言,活塞间隙大小对该系统性能影响更大,这是导致效率变化的关键因素之一。经过优化计算,设计了一台四单元双作用自由活塞斯特林发电机,在加热温度600?C、放热温度20?C和平均压力8 MPa的额定工况下,每个发电单元可输出1.41 k W的电功,热电效率为40.8%,为后续实验研究奠定相关的理论基础。展开更多
In this paper, an experimental investigation of a traveling-wave thermoacoustic electricity generator, which consists of a traveling-wave thermoacoustic heat engine and a linear alternator driven by that engine, is pr...In this paper, an experimental investigation of a traveling-wave thermoacoustic electricity generator, which consists of a traveling-wave thermoacoustic heat engine and a linear alternator driven by that engine, is presented. Using the results of previous theoretical and experimental research, we designed and fabricated a traveling-wave thermoacoustic heat engine and a linear alternator. In the experiments, 450.9 W of electrical power was obtained with a maximum thermal-to-electrical efficiency of 15.03%, and a maximum electrical power of 481.0 W was achieved with 12.65% thermal-to-electrical efficiency.展开更多
A "double-gas acoustic amplifier" is introduced to couple a thermoacoustic heat engine and a two-stage pulse tube cooler in this paper. Compared with previous acoustic amplifiers, this new acoustic amplifier...A "double-gas acoustic amplifier" is introduced to couple a thermoacoustic heat engine and a two-stage pulse tube cooler in this paper. Compared with previous acoustic amplifiers, this new acoustic amplifier maintains the function of amplification for pressure amplitude. In particular, the novel acoustic amplifier with a reservoir makes it possible to install an acoustic transparent but gas blocking elastic membrane between the engine and the cooler. Thus, the engine can use nitrogen as the working gas to work at low frequency; and meanwhile, the cooler can still use helium as the working gas to maintain its high performance. With this new amplifier, the cooling temperature of a two-stage pulse tube cooler driven by an energy-focused thermoacoustic engine reached 18.7 K.展开更多
Experimental investigation on a traveling-wave thermoacoustic electricity generator is presented. In the experiment, more than 100 W electrical power was achieved under 2.5 MPa mean pressure, 64 Hz working frequency a...Experimental investigation on a traveling-wave thermoacoustic electricity generator is presented. In the experiment, more than 100 W electrical power was achieved under 2.5 MPa mean pressure, 64 Hz working frequency and 0.2 MPa pressure amplitude.展开更多
Thermoacoustically-driven pulse tube cooler can provide cryogenic cooling power with no moving com-ponents. Up to now, pulse tube cooler is directly coupled with the thermoacoustic engine and obtainable pressure ratio...Thermoacoustically-driven pulse tube cooler can provide cryogenic cooling power with no moving com-ponents. Up to now, pulse tube cooler is directly coupled with the thermoacoustic engine and obtainable pressure ratio for the pulse tube cooler is limited by the capability of the ther-moacoustic engine. The authors propose here the concept of acoustic amplifier, which is actually a long tube connecting the engine with the pulse tube cooler. Theoretical calculation shows that suitable length and diameter of the tube can lead to a pressure wave amplification effect which means that pressure wave amplitude coming from the thermoacoustic engine can be much amplified to drive the pulse tube cooler. Based on this, a 2.8 m long copper tube with 8 mm inner diameter is used as the acoustic amplifier in experiments. The experimental results show that due to the amplification effect, pressure wave amplitude at the inlet of the pulse tube cooler is over 2.5 times of that at the engine outlet. Typically, with 1.67 kW heating power, the pressure ratio provided by the engine is 1.11 while at the inlet of the pulse tube cooler the pressure ratio is 1.32, which leads to a lowest no-load temperature of 65.7 K.展开更多
The inertance tube is one of the key components of a pulse tube cryocooler. It has great influence not only on the efficiency of the pulse tube cryocooler, but also on the efficiency of the linear compressor. Meanwhil...The inertance tube is one of the key components of a pulse tube cryocooler. It has great influence not only on the efficiency of the pulse tube cryocooler, but also on the efficiency of the linear compressor. Meanwhile, it is very difficult to predict the impedance of an inertance tube because of the turbulent flow. In this paper, using a quasi-turbulent model, the inertance tube is optimized to match a linear compressor driven pulse tube cryocooler. Experimental results show that this model can predict the impedance quite well. With 127 W input electric power, the pulse tube cryocooler obtains 9.4 W cooling power at a temperature of 77 K. The relative Carnot efficiency of the whole system reaches 19.8%.展开更多
The working principle of an efficient travelling- wave thermoacoustic refrigerator operating in room-tem- perature range has been analyzed and an experimental set-up has been built. The experiment showed that suppress...The working principle of an efficient travelling- wave thermoacoustic refrigerator operating in room-tem- perature range has been analyzed and an experimental set-up has been built. The experiment showed that suppress- ing DC-flow streaming was very critical to efficient operation, and an elastic membrane was used to solve the problem suc- cessfully. At the most efficient operating point, the novel thermoacoustic refrigerator achieved a cooling capacity of about 80 W at ?20℃, with a much higher efficiency than previously developed standing-wave thermoacoustic refrig- erator.展开更多
文摘自由活塞斯特林发动机作为一种高效的能源转换装置,在可再生能源利用等领域有重要的应用前景。本文针对一种双作用自由活塞型斯特林发电系统,从声电耦合原理出发,推导了双作用斯特林发动机与直线电机之间的阻抗匹配方程,建立了发电系统的整机数值模型,并获得了加热温度、平均压力、活塞连杆直径、机械阻尼和间隙密封宽度等参数对整机性能的影响规律。结果表明,由于双作用活塞两侧同时存在较大的温差和压差,因此相较于单作用结构的系统而言,活塞间隙大小对该系统性能影响更大,这是导致效率变化的关键因素之一。经过优化计算,设计了一台四单元双作用自由活塞斯特林发电机,在加热温度600?C、放热温度20?C和平均压力8 MPa的额定工况下,每个发电单元可输出1.41 k W的电功,热电效率为40.8%,为后续实验研究奠定相关的理论基础。
基金supported by the National Basic Research Program of China (2010CB227303)the National Natural Sciences Foundation of China (50707034)
文摘In this paper, an experimental investigation of a traveling-wave thermoacoustic electricity generator, which consists of a traveling-wave thermoacoustic heat engine and a linear alternator driven by that engine, is presented. Using the results of previous theoretical and experimental research, we designed and fabricated a traveling-wave thermoacoustic heat engine and a linear alternator. In the experiments, 450.9 W of electrical power was obtained with a maximum thermal-to-electrical efficiency of 15.03%, and a maximum electrical power of 481.0 W was achieved with 12.65% thermal-to-electrical efficiency.
基金Supported by the National Natural Science Foundation of China (Grant Nos. 50536040 and 50506031)
文摘A "double-gas acoustic amplifier" is introduced to couple a thermoacoustic heat engine and a two-stage pulse tube cooler in this paper. Compared with previous acoustic amplifiers, this new acoustic amplifier maintains the function of amplification for pressure amplitude. In particular, the novel acoustic amplifier with a reservoir makes it possible to install an acoustic transparent but gas blocking elastic membrane between the engine and the cooler. Thus, the engine can use nitrogen as the working gas to work at low frequency; and meanwhile, the cooler can still use helium as the working gas to maintain its high performance. With this new amplifier, the cooling temperature of a two-stage pulse tube cooler driven by an energy-focused thermoacoustic engine reached 18.7 K.
基金Supported by the National Natural Science Foundation of China (Grant Nos. 50536040 and 50625620)
文摘Experimental investigation on a traveling-wave thermoacoustic electricity generator is presented. In the experiment, more than 100 W electrical power was achieved under 2.5 MPa mean pressure, 64 Hz working frequency and 0.2 MPa pressure amplitude.
基金supported by the Chinese Academy of Sciences(Project Number:KJCX2-SW-W12-l).
文摘Thermoacoustically-driven pulse tube cooler can provide cryogenic cooling power with no moving com-ponents. Up to now, pulse tube cooler is directly coupled with the thermoacoustic engine and obtainable pressure ratio for the pulse tube cooler is limited by the capability of the ther-moacoustic engine. The authors propose here the concept of acoustic amplifier, which is actually a long tube connecting the engine with the pulse tube cooler. Theoretical calculation shows that suitable length and diameter of the tube can lead to a pressure wave amplification effect which means that pressure wave amplitude coming from the thermoacoustic engine can be much amplified to drive the pulse tube cooler. Based on this, a 2.8 m long copper tube with 8 mm inner diameter is used as the acoustic amplifier in experiments. The experimental results show that due to the amplification effect, pressure wave amplitude at the inlet of the pulse tube cooler is over 2.5 times of that at the engine outlet. Typically, with 1.67 kW heating power, the pressure ratio provided by the engine is 1.11 while at the inlet of the pulse tube cooler the pressure ratio is 1.32, which leads to a lowest no-load temperature of 65.7 K.
基金Supported by the National Natural Science Foundation of China (Grant No. 10874190)National Science Foundation of China for Distinguished Young Scholars (Grant No. 50625620)
文摘The inertance tube is one of the key components of a pulse tube cryocooler. It has great influence not only on the efficiency of the pulse tube cryocooler, but also on the efficiency of the linear compressor. Meanwhile, it is very difficult to predict the impedance of an inertance tube because of the turbulent flow. In this paper, using a quasi-turbulent model, the inertance tube is optimized to match a linear compressor driven pulse tube cryocooler. Experimental results show that this model can predict the impedance quite well. With 127 W input electric power, the pulse tube cryocooler obtains 9.4 W cooling power at a temperature of 77 K. The relative Carnot efficiency of the whole system reaches 19.8%.
基金supported by the Key Project of the National Natural Science Foundation of China(Grant No.50536040)Chinese Academy of Sciences(Grant No.KJCX2-SW-W12-01)
文摘The working principle of an efficient travelling- wave thermoacoustic refrigerator operating in room-tem- perature range has been analyzed and an experimental set-up has been built. The experiment showed that suppress- ing DC-flow streaming was very critical to efficient operation, and an elastic membrane was used to solve the problem suc- cessfully. At the most efficient operating point, the novel thermoacoustic refrigerator achieved a cooling capacity of about 80 W at ?20℃, with a much higher efficiency than previously developed standing-wave thermoacoustic refrig- erator.
