Opportunity of external combustion engines usage in forestry complex

The general cycle model of a class of external combustion engines is established in which the influence of the multi-irreversibilities mainly resulting from the linear heat-loss model between the high and low heat reservoir, and the irreversible adiabatic processes. Some important parameters such as the power output, efficiency and the temperatures of the working substance are calculated and some important characteristic curves are given. The results obtained in this paper may provide some theoretical guidance for the optimal design of the Carnot, Brayton, Braysson and some new heat engines.

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Engine options for the car of tomorrow: Competing internal and external combustion engines, as well as electrics, are considered as contenders

IEEE Spectrum ◽

10.1109/mspec.1977.6501653 ◽

1977 ◽

Vol 14 (11) ◽

pp. 57-62

Author(s):

John D. Withrow

Keyword(s):

Combustion Engines ◽

External Combustion

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A New Approach to Understanding Engineering Thermodynamics From Its Molecular Basis

Volume 5: Education and Globalization; General Topics ◽

10.1115/imece2012-85208 ◽

2012 ◽

Author(s):

W. John Dartnall ◽

John A. Reizes

Keyword(s):

Working Fluid ◽

Combustion Engines ◽

New Approach ◽

Heat Engines ◽

Molecular Behavior ◽

Modern Engineering ◽

Prime Concern ◽

And Performance ◽

General Physical ◽

External Combustion

Engineering Thermodynamics is that engineering science in which students learn to analyze dynamic systems involving energy transformations, particularly where some of the energy is in the form of heat. It is well known that people have difficulty in understanding many of the concepts of thermodynamics; in particular, entropy and its consequences. However, even more widely known concepts such as energy and temperature are not simply defined or explained. Why is this lack of understanding and clarity of definition prevalent in this subject? Older engineering thermodynamics textbooks (often containing the words “heat engines” in the title) had a strong emphasis in their early chapters on the general physical details of thermodynamic equipment such as internal and external combustion engines, gas compressors and refrigeration systems. The working fluid in these systems might expand or contract while heat, work and mass might cross the system boundary. The molecular workings within the thermodynamic fluid are not of prime concern to the engineer even though they are to a physicist or chemist. Modern engineering thermodynamics textbooks place great emphasis on mathematical systems designed to analyze the behavior and performance of thermodynamic devices and systems, yet they rarely show, at least early in their presentation, graphical images of the equipment; moreover, they tend to give only passing reference to the molecular behavior of the thermodynamic fluid. This paper presents some teaching strategies for placing a greater emphasis on the physical realities of the equipment in conjunction with the molecular structure of the working fluid in order to facilitate a deeper understanding of thermodynamic performance limitations of equipment.

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Justification of the use of three-component coatings on the basis of Fe-Ni-Cr alloy as details of external combustion engines of land transport machines

10.1063/1.5134207 ◽

2019 ◽

Author(s):

V. V. Schmidt ◽

I. G. Zhikhareva ◽

D. R. Martiuk

Keyword(s):

Combustion Engines ◽

External Combustion

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Energetic and Exergetic Analysis of Building Cogeneration Systems

ASME 2008 2nd International Conference on Energy Sustainability, Volume 1 ◽

10.1115/es2008-54033 ◽

2008 ◽

Author(s):

Yilmaz Yoru ◽

T. Hikmet Karakoc ◽

Arif Hepbasli ◽

Enis T. Turgut

Keyword(s):

Fuel Cells ◽

Solid Oxide Fuel Cells ◽

Gas Turbines ◽

Internal Combustion Engines ◽

Internal Combustion ◽

System Capacity ◽

Combustion Engines ◽

Exergetic Analysis ◽

External Combustion ◽

Thermophotovoltaic Systems

This study deals with types of micro cogeneration (or micro combined heat and power, MCHP) systems and reviews energetic and exergetic analysis of MCHP systems, which are also called building cogeneration systems. These are classified as micro and macro cogeneration systems and figured within subgroups. Previously conducted studies on exergy and energy analyses of internal combustion engines (micro turbines), external combustion engines (Ericsson engines), fuel cells (solid oxide fuel cells) and thermophotovoltaic systems are treated in this paper. The main objectives of this study are to classify MCHP systems used in building cogeneration systems, to introduce types of MCHP systems and to better define micro cogeneration systems in the light of previously conducted studies. In this regard, energetic and exergetic efficiencies of various MCHP systems are graphically obtained. Under grouping presented MCHP systems, internal combustion engines based MCHP systems are defined to be the best choice with energetic and exergetic efficiency values of 86.0% and 40.31%, respectively. Micro gas turbines and Ericson engine based micro cogeneration systems are also obtained as valuable systems with the energetic values of 75.99% and 65.97% and exergetic values of 35.8% and 38.5%, respectively. However, in this building cogeneration group, energetic and exergetic efficiencies of the thermophotovoltaic systems have 65.0% and 15.0%, respectively. It may be concluded that system choice depends on the type of the system, energy flow of the system, system parts and developments, while building, system capacity, comfort and maintenance are the other factors to be considered.

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