Numerical Study on the Characteristics of Methane Hedging Combustion in a Heat Cycle Porous Media Burner

With the rapid development of portable devices and micro-small sensors, the demand for small-scale power supplies and high-energy-density energy supply systems is increasing. Comparing with the current popular lithium batteries, micro-scale burners based on micro-thermal photoelectric systems have features of high power density and high energy density, the micro-scale burner is the most critical part of the micro-thermal photovoltaic system. In this paper, the combustor was designed as a heat cycle structure and filled with porous media to improve the combustion characteristics of the micro combustor. In addition, the influence of the porous media distribution on the burner center temperature and wall temperature distribution were studied through numerical simulation. Furthermore, the temperature distribution of the combustor was studied by changing the porous media parameters and the wall parameters. The research results show that the heat cycle structure can reduce heat loss and improve combustion efficiency. When the combustion chamber is filled with porous media, it makes the radial center temperature rise by about 50 K and the temperature distribution more uniform. When filling the heat cycle channel with porous media the wall temperature can be increased. Finally, the study also found that as methane is combusted in the combustor, the temperature of the outer wall gradually increases as the intake air velocity increases. The results of this study provide a theoretical and practical basis for the further design of high-efficiency combustion micro-scale burners in the future.

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Slit-wire camera, a new diagnostics method for measurement of small scale high-energy density structures in hot plasmas

Review of Scientific Instruments ◽

10.1063/1.1480462 ◽

2002 ◽

Vol 73 (6) ◽

pp. 2276-2281 ◽

Cited By ~ 15

Author(s):

P. Choi ◽

C. Dumitrescu ◽

E. Wyndham ◽

M. Favre ◽

H. Chuaqui

Keyword(s):

Energy Density ◽

High Energy ◽

High Energy Density ◽

Small Scale

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Design and Testing of a Micromix Combustor With Recuperative Wall Cooling for a Hydrogen Fuelled μ-Scale Gas Turbine

Volume 5: Industrial and Cogeneration; Microturbines and Small Turbomachinery; Oil and Gas Applications; Wind Turbine Technology ◽

10.1115/gt2010-23453 ◽

2010 ◽

Author(s):

A. E. Robinson ◽

H. H.-W. Funke ◽

P. Hendrick ◽

R. Wagemakers

Keyword(s):

Combustion Chamber ◽

Gas Turbine ◽

Mass Flow ◽

Gas Turbines ◽

High Energy ◽

High Energy Density ◽

Energy Output ◽

Experimental Investigations ◽

Small Scale ◽

Micro Scale

For more than a decade up to now there is an ongoing interest in small gas turbines downsized to micro-scale. With their high energy density they offer a great potential as a substitute for today’s unwieldy accumulators, found in a variety of applications like laptops, small tools etc. But micro-scale gas turbines could not only be used for generating electricity, they could also produce thrust for powering small unmanned aerial vehicles (UAVs) or similar devices. Beneath all the great design challenges with the rotating parts of the turbomachinery at this small scale, another crucial item is in fact the combustion chamber needed for a safe and reliable operation. With the so called regular micromix burning principle for hydrogen successfully downscaled in an initial combustion chamber prototype of 10 kW energy output, this paper describes a new design attempt aimed at the integration possibilities in a μ-scale gas turbine. For manufacturing the combustion chamber completely out of stainless steel components, a recuperative wall cooling was introduced to keep the temperatures in an acceptable range. Also a new way of an integrated ignition was developed. The detailed description of the prototype’s design is followed by an in depth report about the test results. The experimental investigations comprise a set of mass flow variations, coupled with a variation of the equivalence ratio for each mass flow at different inlet temperatures and pressures. With the data obtained by an exhaust gas analysis, a full characterisation concerning combustion efficiency and stability of the prototype chamber is possible. Furthermore the data show a full compliance with the expected operating requirements of the designated μ-scale gas turbine.

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Modeling, characterization and evaluation of MU100 high-energy density ceramic nanodielectric for use in pulsed power applications

10.32469/10355/77462 ◽

2017 ◽

Author(s):

◽

Alexander B. Howard

Keyword(s):

Energy Density ◽

Dielectric Strength ◽

High Energy ◽

Pulsed Power ◽

High Energy Density ◽

Small Scale ◽

University Of Missouri ◽

High Dielectric ◽

The University ◽

Preparation And Evaluation

A high dielectric, nanodielectric, composite material, MU100, was developed by the University of Missouri for use in dielectric loaded antennas. Based on its dielectric strength and losses, MU100 had possible uses in the development for high energy-density capacitors. This work presents the theory behind, methods of preparation and evaluation, modeling and properties of MU100. MU100â€™s dielectric properties are explored in high energy-density pulsed power applications, compact high voltage capacitors. Small scale tests have shown the average dielectric strength of MU100 to be 225 kV/cm with a peak break down field of 328 kV/cm. When potted, these small-scale capacitors have lifetimes in excess of 800,000 discharges at 80% of their maximum rated field strength. This shows a remarkable development in the performance of high energy density capacitors for use in pulsed power applications.

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Theoretical Design and Screening Potential High Energy Density Materials: Combination of 1,2,4-oxadiazole and 1,3,4-oxadiazole Rings

Физика горения и взрыва ◽

10.15372/fgv20190504 ◽

2019 ◽

Keyword(s):

Energy Density ◽

High Energy ◽

High Energy Density ◽

Theoretical Design ◽

High Energy Density Materials

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Evaluation of High Energy Density Plasma in Counter-facing Plasma Focus Device driven by Laser Triggered Pulse Power System

IEEJ Transactions on Fundamentals and Materials ◽

10.1541/ieejfms.137.564 ◽

2017 ◽

Vol 137 (10) ◽

pp. 564-569

Author(s):

Tatsuya Sodekoda ◽

Hajime Kuwabara ◽

Shotaro Kittaka ◽

Kazuhiko Horioka

Keyword(s):

Energy Density ◽

Power System ◽

Plasma Focus ◽

High Energy ◽

Pulse Power ◽

Plasma Focus Device ◽

High Energy Density ◽

Density Plasma

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A HIGH ENERGY DENSITY ZINC/OXYGEN BATTERY SYSTEM

10.2514/6.1966-2324 ◽

1966 ◽

Author(s):

S. CHODOSH ◽

E. KATSOULIS ◽

M. ROSANSKY

Keyword(s):

Energy Density ◽

High Energy ◽

High Energy Density ◽

Battery System

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Efficient Co-Harvesting of Solar Energy and Low-Grade Heat by Molecular Photoswitches for High Energy Density, Long-Term Stable Solar Thermal Battery

10.26434/chemrxiv.9730694.v1 ◽

2019 ◽

Author(s):

Zhao-Yang Zhang ◽

Tao LI

Keyword(s):

Energy Density ◽

Solar Energy ◽

High Performance ◽

High Energy ◽

Solar Thermal ◽

High Energy Density ◽

Low Grade ◽

Thermal Battery ◽

Low Grade Heat

Solar energy and ambient heat are two inexhaustible energy sources for addressing the global challenge of energy and sustainability. Solar thermal battery based on molecular switches that can store solar energy and release it as heat has recently attracted great interest, but its development is severely limited by both low energy density and short storage stability. On the other hand, the efficient recovery and upgrading of low-grade heat, especially that of the ambient heat, has been a great challenge. Here we report that solar energy and ambient heat can be simultaneously harvested and stored, which is enabled by room-temperature photochemical crystal-to-liquid transitions of small-molecule photoswitches. The two forms of energy are released together to produce high-temperature heat during the reverse photochemical phase change. This strategy, combined with molecular design, provides high energy density of 320-370 J/g and long-term storage stability (half-life of about 3 months). On this basis, we fabricate high-performance, flexible film devices of solar thermal battery, which can be readily recharged at room temperature with good cycling ability, show fast rate of heat release, and produce high-temperature heat that is >20<sup> o</sup>C higher than the ambient temperature. Our work opens up a new avenue to harvest ambient heat, and demonstrate a feasible strategy to develop high-performance solar thermal battery.

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