Effect of temperature distribution of thermal buffer tube on onset temperature in a straight-tube-type thermoacoustic prime mover

Abstract In this report, we proposed the installation of a Conical Phase Adjuster (CPA) in a thermoacoustic prime mover as a method for reducing the onset temperature and investigated the effect of the installation position of CPA on the onset temperature using stability analysis. The onset temperature of CPA also was investigated experimentally by changing the installation position of CPA. As a result, when CPA was installed at 1000 mm from the high-temperature end of the stack, the onset temperature was 195 K lower than the onset temperature without CPA, that is, the installation of CPA in a loop-tube-type thermoacoustic prime mover reduced the onset temperature by 29 %. Comparing onset temperatures of PA had installed in a system, CPA is considered to have the same effect as PA because the onset temperature tendency of CPA to reduce at the installation position agrees with that of PA.

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Effect of expanded part length on quality value in straight-tube-type thermoacoustic system with a diameter-expanded prime mover

Japanese Journal of Applied Physics ◽

10.7567/jjap.57.07le10 ◽

2018 ◽

Vol 57 (7S1) ◽

pp. 07LE10

Author(s):

Kohei Egawa ◽

Shin-ichi Sakamoto ◽

Yuichiro Orino ◽

Yuya Yamaga ◽

Kenshiro Inui

Keyword(s):

Straight Tube ◽

Prime Mover ◽

Tube Type ◽

Quality Value

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Finite Element Analysis of Temperature Distribution and Stress Behavior of Squeeze Pressure Composites

Advances in Materials Science and Engineering ◽

10.1155/2021/8665674 ◽

2021 ◽

Vol 2021 ◽

pp. 1-9

Author(s):

P. Gurusamy ◽

T. Sathish ◽

V. Mohanavel ◽

Alagar Karthick ◽

M. Ravichandran ◽

...

Keyword(s):

Finite Element ◽

Temperature Distribution ◽

Cooling Rate ◽

Base Alloy ◽

Cast Alloy ◽

Simulation Software ◽

Engineering Industry ◽

Effect Of Temperature ◽

Cooling Curves ◽

Squeeze Pressure

Aluminium-reinforced composites play a vital role in the engineering industry because of their better strength and stiffness. The properties are directly related to the solidification phenomenon of the cast alloy. The design engineer should understand the importance of the solidification behavior of base alloy and its reinforcement. Composites’ solidification study is rare, and the reviews are limited. The solidification process is analyzed using the finite element method (FEM), and this would fetch a lot of information about the cooling rate of the composites and also helps to reduce the time in experimentation. This paper reports and plots the cooling curves of Al/SiCp composites using simulation software. Cylindrical-shaped composites were developed using the squeeze casting method, and the experimental cooling curves were plotted using a K-type thermocouple. Composites samples were prepared at the following squeeze pressures: 0, 30, 50, 70, 100, and 130 MPa; melt and die temperature was kept constant at 800 and 400°C, respectively. The experimental and FEA cooling curves were compared, and it was agreed that the increase in the squeeze pressure increases the cooling rate of the developed composite. Furthermore, the effect of temperature distribution from the inner region of the melt and die material which causes the radial and tangential stress of components has also been examined.

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Experimental and CFD investigation on temperature distribution of a serpentine tube type photovoltaic/thermal collector

Solar Energy ◽

10.1016/j.solener.2018.09.063 ◽

2018 ◽

Vol 174 ◽

pp. 735-742 ◽

Cited By ~ 4

Author(s):

Jicheng Zhou ◽

Haoyun Ke ◽

Xiaoqing Deng

Keyword(s):

Temperature Distribution ◽

Tube Type

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Theoretical Model of a Flow in a Tube With a Slit

Volume 3A: Fluid Applications and Systems ◽

10.1115/ajkfluids2019-5257 ◽

2019 ◽

Cited By ~ 1

Author(s):

Yuki Toda ◽

Masataka Morimatsu ◽

Yu Nishio ◽

Takanobu Ogawa

Keyword(s):

Theoretical Model ◽

Flow Field ◽

Pressure Loss ◽

Longitudinal Direction ◽

Gas Mixture ◽

Straight Tube ◽

One Dimensional ◽

Tube Type ◽

Gas Burner

Abstract A tube-type gas burner consists of a straight tube with a slit along it and discharges an air-gas mixture through the slit to produce a flame. The flow velocity from the slit depends on the pressure in the tube and the pressure loss at the slit, and it varies in the longitudinal direction of the tube. The resulting uneven flame degrades the quality of the burner. In this study, we develop a one-dimensional theoretical model of the flow in a tube with a slit. To validate the result of the theoretical model, we also conduct experiments and numerical simulations for the same flow field. We applied this theoretical model to a flow in a tube, 1 m length, 40 mm in diameter, with a slit 2.5 mm wide. The end of the tube is closed. We also discuss the effect of the length of the burner on the unevenness.

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Seamless Tube-Type Heater with Uniform Thickness and Temperature Distribution Based on Carbon Nanotubes Aligned by Circumferential Shearing

Materials ◽

10.3390/ma12203283 ◽

2019 ◽

Vol 12 (20) ◽

pp. 3283 ◽

Cited By ~ 1

Author(s):

Yoonchul Sohn ◽

Dongearn Kim ◽

Sung-Hoon Park ◽

Sang-Eui Lee

Keyword(s):

Temperature Distribution ◽

Axial Direction ◽

Circumferential Direction ◽

Laser Printer ◽

Seamless Tube ◽

Uniform Temperature ◽

Rubber Composite ◽

Tube Type ◽

The Difference

The uniform temperature distribution, one of the requirements for long-term durability, is essential for composite heaters. An analytical model for temperature distribution of a tube-type heater was derived, and it revealed that thickness uniformity is one order more important than intrinsic material properties such as density, heat capacity, and electrical conductivity of the heating tube. We introduced a circumferential shearing process to fabricate a flexible, seamless tube-type heating layer of carbon nanotube/silicone rubber composite with outstanding uniform distribution of thickness and temperature, which may be attributed to a shorter characteristic dimension in the circumferential direction than in the axial direction. The temperature uniformity was experimentally verified at various temperatures under heating. The difference in measured thickness and temperature in circumferential direction was within ±1.3~3.0% (for tavg = 352.7 μm) and ±1.1% (for Tavg = 138.8 °C), respectively, all over the heating tube. Therefore, the circumferential shearing process can be effective for cylindrical heaters, like a heating layer of a laser printer, which fuse toners onto papers during printing.

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A Second Law Approach to Characterising Thermally Stratified Hot Water Storage With Application to Solar Water Heaters

Journal of Solar Energy Engineering ◽

10.1115/1.2888166 ◽

1999 ◽

Vol 121 (4) ◽

pp. 194-200 ◽

Cited By ~ 27

Author(s):

G. Rosengarten ◽

G. Morrison ◽

M. Behnia

Keyword(s):

Temperature Distribution ◽

Heat Exchangers ◽

Water Storage ◽

Heating System ◽

Hot Water ◽

Effect Of Temperature ◽

Storage Efficiency ◽

Water Heating ◽

Solar Water Heating ◽

Solar Water

This paper presents a method of characterising and evaluating the performance of hot water storage systems in terms of their temperature distribution. The change in exergy from the stratified state to the delivery state depends on the stored energy and the stratification. It can thus he used to define the storage efficiency for sensible heat storage devices. A new parameter that isolates the stratification component of the exergy is defined and called the stratification efficiency. The effect of temperature distribution, delivery temperature and tank cross-section on exergy and stratification efficiency is investigated. The advantage that stratification offers over a mixed tank is examined in terms of the storage efficiency and overall solar water heating system performance. Exergy is used to assess the operation of mantle heat exchangers in solar water heating systems and it is shown that exergy and stratification efficiency, as well as energy, should be used to ascertain the performance of such heat exchangers.

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