AN ADVANCED THERMOELECTRIC GENERATION CONCEPT BASED ON STEEP TEMPERATURE GRADIENT YIELDED BY COMBUSTION IN POROUS THERMOELECTRIC ELEMENTS

A brief review is given of observations of the resonance lines of He I and He II and their interpretation. As discussed in a previous paper, the helium lines are anomalously strong in the quiet Sun when compared with other transition region lines. The enhancement can be brought about by the transient excitation of the lines by electrons of higher temperature than that which determines the ion population. The variation in the intensity of the helium lines relative to those of other transition region lines appears to be related to variations in the temperature gradient between different parts of the atmosphere. To relate the degree of enhancement to other observable parameters, such as electron pressure and absolute line intensities, and thus to the structure of the atmosphere, a method for analysing the emission measure distribution previously developed in the context of the quiet atmosphere and active region loops is applied also to coronal holes. It is proposed that the non-thermal ion motions observed in the transition region can provide the required mechanism for transporting the helium ions across the steep temperature gradient. By making a simple model, an expression is developed which relates the helium enhancement to the non-thermal motions, the transition region temperature gradient and the electron pressure. The scaling laws implied can be tested against further observations when they become available.

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STEEP TEMPERATURE GRADIENT NEAR LAKE ERIE

Bulletin of the American Meteorological Society ◽

10.1175/1520-0477-14.5.149b ◽

1933 ◽

Vol 14 (5) ◽

pp. 149b-150

Keyword(s):

Temperature Gradient ◽

Lake Erie ◽

Steep Temperature Gradient

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Furnace for growing single crystals in a very steep temperature gradient

phys stat sol (a) ◽

10.1002/pssa.19700010223 ◽

1970 ◽

Vol 1 (2) ◽

pp. K63-K64

Author(s):

H. D. Riccius ◽

W. E. E. Berger ◽

C. J. van der Hoeven

Keyword(s):

Temperature Gradient ◽

Single Crystals ◽

Steep Temperature Gradient

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Mechanism of Mild Cooling by Crystallisation of Mould Flux for Continuous Casting of Steel - A View from Apparent Thermal Conductivity under Steep Temperature Gradient -

ISIJ International ◽

10.2355/isijinternational.isijint-2017-661 ◽

2018 ◽

Vol 58 (5) ◽

pp. 905-914 ◽

Cited By ~ 5

Author(s):

Shunsuke Takahashi ◽

Rie Endo ◽

Takashi Watanabe ◽

Miyuki Hayashi ◽

Masahiro Susa

Keyword(s):

Thermal Conductivity ◽

Temperature Gradient ◽

Continuous Casting ◽

Continuous Casting Of Steel ◽

Apparent Thermal Conductivity ◽

Mould Flux ◽

Steep Temperature Gradient

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Simplification of sound-pressure characteristics using narrow flow channels subject with temperature gradient

MATEC Web of Conferences ◽

10.1051/matecconf/201819202025 ◽

2018 ◽

Vol 192 ◽

pp. 02025

Author(s):

Tomoaki Kyoden

Keyword(s):

Temperature Gradient ◽

Heat Energy ◽

Wire Mesh ◽

Thermoacoustic Engine ◽

Sound Energy ◽

Flow Channels ◽

Mesh Screen ◽

Steep Temperature Gradient ◽

Noise Energy ◽

Made In

A thermoacoustic engine is one of promising system for utilization of unused energy. The object of this paper is to study the system of unused energy, such as heat energy and sound energy in noise using thermoacoustic engine. The thermoacoustic engine is composed of a stack sandwiched by two heat exchangers and tube. The stack has many narrow flow channels and its length for 50 mm. For example, in order to create narrow flow channels, the stack is comprised of wire-mesh screen. When the steep temperature gradient is made in the stack, a self-exited gas oscillation is generated. Thus, heat energy can be converted into sound energy. In this paper, thermoacoustic conversion device applied for noise energy generated from engine plants was presented. The noise has complicated frequency characteristics and low energy density. We demonstrated selective amplification of acoustic pressure only one-frequency in noise by utilization of the technique of thermoacoustic engine. In addition, the other frequencies were attenuated by viscosity dissipation in the stack. Summarizing these results, the simplification and amplified sound was created from complex noise.

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