Experimental Study of the Minto Engine—A Heat Engine for Converting Low Grade Heat to Mechanical Energy

The Minto engine is a liquid piston heat engine that converts heat energy into mechanical energy. Evaporation of the heated, volatile working fluid pushes it upwards against gravity. This causes the device to tip over and rotate. A 500 mm diameter Minto engine which used petroleum ether as the working fluid, was built and was operated between 344 K and 294 K. Thermal efficiencies of up to 0.25% (i.e. 1.7% of the Carnot maximum) were measured. This engine behaves as a power amplifier. It absorbs low grade heat over a long period of time and suddenly releases it as a pulse of mechanical energy over a short period of time.

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Rolling membrane powered by low-temperature steam as a new approach to generate mechanical energy

Scientific Reports ◽

10.1038/s41598-020-73732-7 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Chongshan Yin ◽

Qicheng Liu ◽

Qing Liu

Keyword(s):

Water Vapor ◽

Low Temperature ◽

Combustion Engine ◽

Mechanical Energy ◽

Heat Energy ◽

Steam Engine ◽

Low Grade ◽

Human Society ◽

New Approach ◽

Low Grade Heat

Abstract How to convert heat energy into other forms of usable energy more efficiently is always crucial for our human society. In traditional heat engines, such as the steam engine and the internal combustion engine, high-grade heat energy can be easily converted into mechanical energy, while a large amount of low-grade heat energy is usually wasted owing to its disadvantage in the temperature level. In this work, for the first time, the generation of mechanical energy from both high- and low-temperature steam is implemented by a hydrophilic polymer membrane. When exposed to water vapor with a temperature ranging from 50 to 100 °C, the membrane repeats rolling from one side to another. In nature, this continuously rolling of membrane is powered by the steam, like a miniaturized “steam engine”. The differential concentration of water vapor (steam) on the two sides of the membrane generates the asymmetric swelling, the curve, and the rolling of the membrane. In particular, results suggest that this membrane based “steam engine” can be powered by the steam with a relatively very low temperature of 50 °C, which indicates a new approach to make use of both the high- and low-temperature heat energy.

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Innovative Research in the Organic Rankine Cycle

Impact ◽

10.21820/23987073.2020.6.76 ◽

2020 ◽

Vol 2020 (6) ◽

pp. 76-78

Author(s):

Tzu-Chen Hung ◽

Yong-Qiang Feng

Keyword(s):

Phase Change ◽

Mechanical Energy ◽

Heat Engine ◽

Organic Rankine Cycle ◽

Rankine Cycle ◽

Vapour Phase ◽

Working Fluid ◽

Low Grade ◽

Initial State ◽

Thermodynamic Cycles

Thermodynamic cycles consist of a sequence of thermodynamic processes involving the transfer of heat and work into and then out of a system. Variables, such as pressure and temperature, eventually return the system to its initial state. During the process of passing through the system, the working fluid converts heat and disposes of any remaining heat, making the cycle act as a heat engine, where heat or thermal energy is converted into mechanical energy. Thermodynamic cycles are an efficient means of producing energy and one of the most well-known examples is a Rankine cycle. From there, scientists have developed the organic Rankine cycle (ORC), which uses fluid with a liquid to vapour phase change that occurs at a lower temperature than the water to steam phase change. Dr Tzu-Chen Hung and Dr Yong-Qiang Feng, who are based at both the Department of Mechanical Engineering, National Taipei University in Taiwan, and the School of Energy and Power Engineering, Jiangsu University in China, are carrying out work that seeks to design and build improved ORC systems which can be used for low-grade heat to power conversion.

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Experimental study of a low grade heat driven ejector cooling system using the working fluid R245fa

International Journal of Refrigeration ◽

10.1016/j.ijrefrig.2017.11.018 ◽

2018 ◽

Vol 86 ◽

pp. 388-400 ◽

Cited By ~ 19

Author(s):

Malek Hamzaoui ◽

Hakim Nesreddine ◽

Zine Aidoun ◽

Mourad Balistrou

Keyword(s):

Experimental Study ◽

Cooling System ◽

Working Fluid ◽

Low Grade ◽

Low Grade Heat

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Experimental study on diffusion absorption refrigerator achieving 0.2 coefficient of performance using low global warming potential refrigerant and low-grade heat source

Applied Thermal Engineering ◽

10.1016/j.applthermaleng.2021.117803 ◽

2021 ◽

pp. 117803

Author(s):

Hyung Won Choi ◽

Jae Won Lee ◽

Yong Tae Kang

Keyword(s):

Experimental Study ◽

Global Warming ◽

Heat Source ◽

Global Warming Potential ◽

Coefficient Of Performance ◽

Low Grade ◽

Low Global Warming Potential ◽

Absorption Refrigerator ◽

Low Grade Heat ◽

Diffusion Absorption

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An Experimental Study of Adsorption Cooling System by Using Low Grade Heat Source

2018 IEEE PES/IAS PowerAfrica ◽

10.1109/powerafrica.2018.8520999 ◽

2018 ◽

Author(s):

H. M. Elgohary ◽

H. M. Soliman ◽

A. M. Soliman ◽

H. H. Gouda ◽

S.P. Chowdhury

Keyword(s):

Experimental Study ◽

Heat Source ◽

Cooling System ◽

Low Grade ◽

Adsorption Cooling System ◽

Low Grade Heat

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Converting Low-Grade Heat Into Power Using a Supercritical Rankine Cycle With Zeotropic Mixture Working Fluid

ASME 2010 4th International Conference on Energy Sustainability, Volume 1 ◽

10.1115/es2010-90089 ◽

2010 ◽

Cited By ~ 1

Author(s):

Huijuan Chen ◽

D. Yogi Goswami ◽

Muhammad M. Rahman ◽

Elias K. Stefanakos

Keyword(s):

Rankine Cycle ◽

Phase Region ◽

Working Fluid ◽

Condensation Process ◽

Heating Process ◽

Low Grade ◽

Two Phase ◽

Working Fluids ◽

Zeotropic Mixture ◽

Low Grade Heat

A supercritical Rankine cycle using zeotropic mixture working fluids for the conversion of low-grade heat into power is proposed and analyzed in this paper. A supercritical Rankine cycle does not go through two-phase region during the heating process. By adopting zeotropic mixtures as the working fluids, the condensation process happens non-isothermally. Both of the features create a potential in reducing the irreversibility and improving the system efficiency. A comparative study between an organic Rankine cycle and the proposed supercritical Rankine cycle shows that the proposed cycle improves the cycle thermal efficiency, exergy efficiency of the heating and the condensation processes, and the system overall efficiency.

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