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Recent Advances in Internal Combustion Engines

A special issue of Energies (ISSN 1996-1073). This special issue belongs to the section "J: Thermal Management".

Deadline for manuscript submissions: closed (31 August 2021) | Viewed by 26775

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Guest Editor
Director, Technion Internal Combustion Engines Laboratory, Faculty of Mechanical Engineering, Israel Institute of Technology, Technion City, Haifa 3200003, Israel
Interests: thermofluids; waste heat recovery in electric, hybrid and motor vehicles; thermochemical recuperation; combustion; UAV propulsion; alternative fuels; pollutant formation and emissions
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Special Issue Information

Dear Colleagues,

We cordially invite you to submit original and unpublished research work or recommend papers, to be published in a Special Issue of Energies devoted to recent advances in internal combustion engines. Climate change, the security of energy supply, and air pollution challenges require out-of-the-box thinking and development of ‎new propulsion concepts that would enable meeting CO2-neutral economy and zero-impact emission ‎requirements, applying highly-efficient energy conversion processes, and using renewable energy ‎sources. We believe that internal combustion engines (ICEs) fed with alternative renewable fuels are able to meet these challenges most successfully. For this purpose, efficient waste heat ‎recovery and combustion methods together with novel engine and aftertreatment concepts, materials, and control strategies are being developed. Advances in engine technology, especially when combined with electrification, further widen the vast potential of ICE efficiency improvement and emission mitigation. The use in engines of synthetic electrofuels produced through CO2 capturing opens new horizons of electric energy storage together with carbon footprint and target emission mitigation.

The main goal of this Special Issue is to provide a scientific and technological endeavor for experts all over the globe to promote, share, and discuss challenging new issues and developments in various aspects of internal combustion engine theory and technology.

This Special Issue of Energies seeks top-quality papers dealing with recent advances in ICE technology. Original research, review, and case study articles can be submitted.

 Topics of primary interest include but are not limited to:

  • Combustion methods;
  • Waste heat recovery;
  • Gas exchange;
  • Aftertreatment;
  • Thermal management;
  • Alternative fuels;
  • Engine modeling;
  • Engine tribology;
  • Engine and platform control;
  • Electrification.

Prof. Dr. Leonid Tartakovsky
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Energies is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • internal combustion engine
  • energy efficiency
  • pollutant emission
  • carbon footprint
  • alternative fuels
  • engine simulation

Published Papers (12 papers)

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Research

19 pages, 8761 KiB  
Article
Real Driving Emissions in Extended Driving Conditions
by Danilo Engelmann, Yan Zimmerli, Jan Czerwinski and Peter Bonsack
Energies 2021, 14(21), 7310; https://doi.org/10.3390/en14217310 - 04 Nov 2021
Cited by 5 | Viewed by 1573
Abstract
The real driving emission (RDE) testing for certification of vehicles is performed in conditions that are well defined in legislation. For emissions inventories and for research, the influences of some extended driving conditions on emissions are an interesting issue. In the present work, [...] Read more.
The real driving emission (RDE) testing for certification of vehicles is performed in conditions that are well defined in legislation. For emissions inventories and for research, the influences of some extended driving conditions on emissions are an interesting issue. In the present work, some examples of RDE results from two common passenger cars with gasoline and diesel propulsion are given. The varying driving conditions were “winter/summer”, “mild/aggressive”, and “higher altitude/slop”. The driving conditions: “winter”, “aggressive”, and “higher slope/altitude” generally require more energy, cause higher fuel consumption, and therefore, higher CO2-emissions. The condition of “winter driving”, especially in the urban type of operation, may cause some longer phases with not enough warmed-up exhaust aftertreatment and consequently some increased gaseous emissions. The DPF eliminates the nanoparticles (PN) independently on the driving conditions. Nevertheless, the DPF regeneration has an influence on the CO2-normality of the trip. The CO2-normality primary tolerance range can also be exceeded with aggressive driving. The elaborated results confirm the usefulness of the existing legal limits for the driving conditions of RDE homologation tests. Full article
(This article belongs to the Special Issue Recent Advances in Internal Combustion Engines)
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20 pages, 7137 KiB  
Article
The Effect of Crankshaft Phasing and Port Timing Asymmetry on Opposed-Piston Engine Thermal Efficiency
by Alex G. Young, Aaron W. Costall, Daniel Coren and James W. G. Turner
Energies 2021, 14(20), 6696; https://doi.org/10.3390/en14206696 - 15 Oct 2021
Cited by 5 | Viewed by 2606
Abstract
Opposed-piston, two-stroke engines reveal degrees of freedom that make them excellent candidates for next generation, highly efficient internal combustion engines for hybrid electric vehicles and power systems. This article reports simulation results that explore the influence of key control and geometrical parameters, specifically [...] Read more.
Opposed-piston, two-stroke engines reveal degrees of freedom that make them excellent candidates for next generation, highly efficient internal combustion engines for hybrid electric vehicles and power systems. This article reports simulation results that explore the influence of key control and geometrical parameters, specifically crankshaft phasing and intake and exhaust port height-to-stroke ratios, in obtaining best thermal efficiency. A model of a 0.75 L, single-cylinder opposed-piston two-stroke engine is exercised to predict fuel consumption as engine speed, load, crankshaft phasing, intake and exhaust port height-to-stroke ratios, and stoichiometry are varied for medium-duty truck and range extender applications. Under stoichiometric operation, optimal crankshaft phasing is seen at 0–5°, lower than reported in the literature. If stoichiometric operation is not mandated, best fuel consumption is achieved at an air-to-fuel equivalence ratio λ = 1.25 and 5–10° crankshaft phase angle, enabling a ~10 g/kWh (~4%) improvement in average brake-specific fuel consumption across medium-duty truck operating points. In range extender form, the engine provides 30 kW output power in accordance with a survey of range extender engines. In this role, there is a clear distinction between low-speed, high-load operation and vice versa. The decision as to which is more appropriate would be based on minimizing total owning and operating cost, itself a trade-off between better thermal efficiency (and thus lower fuel cost) and greater durability. Full article
(This article belongs to the Special Issue Recent Advances in Internal Combustion Engines)
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41 pages, 17566 KiB  
Article
Influence of Environmental Changes Due to Altitude on Performance, Fuel Consumption and Emissions of a Naturally Aspirated Diesel Engine
by John Jairo Ceballos, Andrés Melgar and Francisco V. Tinaut
Energies 2021, 14(17), 5346; https://doi.org/10.3390/en14175346 - 27 Aug 2021
Cited by 4 | Viewed by 2495
Abstract
The present study shows the effects of environmental conditions (atmospheric temperature, pressure and relative humidity) due to altitude changes on performance, fuel consumption and emissions in a naturally aspirated diesel engine. Due to changes in altitude, the atmospheric conditions are altered, mainly the [...] Read more.
The present study shows the effects of environmental conditions (atmospheric temperature, pressure and relative humidity) due to altitude changes on performance, fuel consumption and emissions in a naturally aspirated diesel engine. Due to changes in altitude, the atmospheric conditions are altered, mainly the air density, associated to hydrostatic pressure, temperature profile and humidity and relative nitrogen/oxygen ratio, thus modifying the engine intake conditions. The study considers changes in altitude from sea level to 2500 m above sea level, which are representative of the orographic conditions in Ecuador. As a main part of this research, a parametric study of variation of atmospheric temperature, pressure and relative humidity is carried out in AVL BOOST™, showing the effects on mean effective pressure, fuel consumption and specific pollutant emissions (CO2, NOx, CO and soot). The study considers effects at regional level (change from an altitude to another) and local level (changes in the atmospheric conditions due to local anticyclone or storm, temperature and humidity). The quantitative effects are expressed in the form of sensitivity coefficients, e.g., relative change in an engine output variable due to the change in atmospheric pressure, temperature or humidity. In addition, several global correlations have been obtained to provide analytical expressions to summarize all results obtained, showing the separate effect of pressure and temperature on each engine performance variable. Full article
(This article belongs to the Special Issue Recent Advances in Internal Combustion Engines)
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11 pages, 3717 KiB  
Article
The Changes of Ergonomic Engine Vibroacoustic Response Regarding Their Development
by Radosław Wróbel, Lech Sitnik, Monika Andrych-Zalewska, Łukasz Łoza, Radostin Dimitrov and Veselin Mihaylov
Energies 2021, 14(14), 4215; https://doi.org/10.3390/en14144215 - 12 Jul 2021
Cited by 2 | Viewed by 1513
Abstract
The article presents the results of research on the vibroacoustic response of internal combustion engines mounted in a vehicle. The vehicles studied belong to popular models, which became available in successive versions. Each group included vehicles of the same model of an older [...] Read more.
The article presents the results of research on the vibroacoustic response of internal combustion engines mounted in a vehicle. The vehicles studied belong to popular models, which became available in successive versions. Each group included vehicles of the same model of an older generation (equipped with a naturally aspirated engine) and of a newer generation, including downsized (and turbocharged) engines. Tests in each group were carried out under repeatable conditions on a chassis-load dynamometer. The vibrations were measured using single-axis accelerometers mounted on the steering wheel, engine, and driver’s head restraint mounting. The primary purpose of the study was to verify whether the new generations of vehicles equipped with additional high-speed elements (compressors) generate additional harmonics (especially those within the range potentially affecting travel comfort and human health) and whether there are significant changes in the distribution of spectral power density in the new generations. As the study showed, new generations of vehicles are characterized by a different vibroacoustic response, and the trend of change is the same in each of the families studied. Full article
(This article belongs to the Special Issue Recent Advances in Internal Combustion Engines)
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18 pages, 15667 KiB  
Article
The Security of Energy Supply from Internal Combustion Engines Using Coal Mine Methane—Forecasting of the Electrical Energy Generation
by Marek Borowski, Piotr Życzkowski, Klaudia Zwolińska, Rafał Łuczak and Zbigniew Kuczera
Energies 2021, 14(11), 3049; https://doi.org/10.3390/en14113049 - 24 May 2021
Cited by 5 | Viewed by 1772
Abstract
Increasing emissions from mining areas and a high global warming potential of methane have caused gas management to become a vital challenge. At the same time, it provides the opportunity to obtain economic benefits. In addition, the use of combined heat and power [...] Read more.
Increasing emissions from mining areas and a high global warming potential of methane have caused gas management to become a vital challenge. At the same time, it provides the opportunity to obtain economic benefits. In addition, the use of combined heat and power (CHP) in the case of coalbed methane combustion enables much more efficient use of this fuel. The article analyses the possibility of electricity production using gas engines fueled with methane captured from the Budryk coal mine in Poland. The basic issue concerning the energy production from coalbed methane is the continuity of supply, which is to ensure the required amount and concentration of the gas mixture for combustion. Hence, the reliability of supply for electricity production is of key importance. The analysis included the basic characterization of both the daily and annual methane capture by the mine’s methane drainage system, as well as the development of predictive models to determine electricity production based on hourly capture and time parameters. To forecast electricity production, predictive models that are based on five parameters have been adopted. Models were prepared based on three time variables, i.e., month, day, hour, and two values from the gas drainage system-capture and concentration of the methane. For this purpose, artificial neural networks with different properties were tested. The developed models have a high value of correlation coefficient. but showed deviations concerning the very low values persisting for a short time. The study shows that electricity production forecasting is possible, but it requires data on many variables that directly affect the production capacity of the system. Full article
(This article belongs to the Special Issue Recent Advances in Internal Combustion Engines)
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24 pages, 5759 KiB  
Article
Increased Internal Combustion Engine Efficiency with Optimized Valve Timings in Extended Stroke Operation
by Andyn Omanovic, Norbert Zsiga, Patrik Soltic and Christopher Onder
Energies 2021, 14(10), 2750; https://doi.org/10.3390/en14102750 - 11 May 2021
Cited by 5 | Viewed by 2698
Abstract
Spark-ignited internal combustion engines are known to exhibit a decreased brake efficiency in part-load operation. Similarly to cylinder deactivation, the x-stroke operation presented in this paper is an adjustable form of skip-cycle operation. It is an effective measure to increase the efficiency of [...] Read more.
Spark-ignited internal combustion engines are known to exhibit a decreased brake efficiency in part-load operation. Similarly to cylinder deactivation, the x-stroke operation presented in this paper is an adjustable form of skip-cycle operation. It is an effective measure to increase the efficiency of an internal combustion engine, which has to be equipped with a variable valve train to enable this feature. This paper presents an optimization procedure for the exhaust valve timings applicable to any valid stroke operation number greater than four. In the first part, the gas spring operation, during which all gas exchange valves are closed, is explained, as well as how it affects the indicated efficiency and the blow-by mass flow. In the second part, a simulation model with variable valve timings, parameterized with measurement data obtained on the engine test, is used to find the optimal valve timings. We show that in 12-stroke operation and with a cylinder load of 5 Nm, an indicated efficiency of 34.3% is achieved. Preloading the gas spring with residual gas prevents oil suction and thus helps to reduce hydrocarbon emissions. Measurements of load variations in 4-, 8-, and 12-stroke operations show that by applying an x-stroke operation, the indicated efficiency remains high and the center of combustion remains optimal in the range of significantly lower torque outputs. Full article
(This article belongs to the Special Issue Recent Advances in Internal Combustion Engines)
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15 pages, 3518 KiB  
Article
CFD/FEA Co-Simulation Framework for Analysis of the Thermal Barrier Coating Design and Its Impact on the HD Diesel Engine Performance
by Sean Moser, K. Dean Edwards, Tobias Schoeffler and Zoran Filipi
Energies 2021, 14(8), 2044; https://doi.org/10.3390/en14082044 - 07 Apr 2021
Cited by 8 | Viewed by 2346
Abstract
Thermal barrier coatings (TBCs) have been investigated both experimentally and through simulation for mixing controlled combustion (MCC) concepts as a method for reducing heat transfer losses and increasing cycle efficiency, but it is still a very active research area. Early studies were inconclusive, [...] Read more.
Thermal barrier coatings (TBCs) have been investigated both experimentally and through simulation for mixing controlled combustion (MCC) concepts as a method for reducing heat transfer losses and increasing cycle efficiency, but it is still a very active research area. Early studies were inconclusive, with different groups discovering obstacles to realizing the theoretical potential. Nuanced papers have shown that coating material properties, thickness, microstructure, and surface morphology/roughness all can impact the efficacy of the thermal barrier coating and must be accounted for. Adding to the complexities, a strong spatial and temporal heat flux inhomogeneity exists for mixing controlled combustion (diesel) imposed onto the surfaces from the impinging flame jets. In support of the United States Department of Energy SuperTruck II program goal to achieve 55% brake thermal efficiency on a heavy-duty diesel engines, this study sought to develop a deeper insight into the inhomogeneous heat flux from mixing controlled combustion on thermal barrier coatings and to infer concrete guidance for designing coatings. To that end, a co-simulation approach was developed that couples high-fidelity computational fluid dynamics (CFD) modeling of in-cylinder processes and combustion, and finite element analysis (FEA) modeling of the thermal barrier-coated and metal engine components to resolve spatial and temporal thermal boundary conditions. The models interface at the surface of the combustion chamber; FEA modeling predicts the spatially resolved surface temperature profile, while CFD develops insights into the effect of the thermal barrier coating on the combustion process and the boundary conditions on the gas side. The paper demonstrates the capability of the framework to estimate cycle impacts of the temperature swing at the surface, as well as identify critical locations on the piston/thermal barrier coating that exhibit the highest charge temperature and highest heat fluxes. In addition, the FEA results include predictions of thermal stresses, thus enabling insight into factors affecting coating durability. An example of the capability of the framework is provided to illustrate its use for investigating novel coatings and provide deeper insights to guide future coating design. Full article
(This article belongs to the Special Issue Recent Advances in Internal Combustion Engines)
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10 pages, 2228 KiB  
Article
A Diesel Engine with a Catalytic Piston Surface to Propel Small Aircraft at High Altitudes—A Theoretical Study
by Kadmiel Karsenty, Leonid Tartakovsky and Eran Sher
Energies 2021, 14(7), 1905; https://doi.org/10.3390/en14071905 - 30 Mar 2021
Cited by 3 | Viewed by 1541
Abstract
Due to the oxygen shortage at high altitudes, the use of diesel engines in small aircraft is limited to a low ceiling level. Here, we propose to significantly extend the ceiling level by introducing an in-cylinder steam reforming system. In this arrangement, the [...] Read more.
Due to the oxygen shortage at high altitudes, the use of diesel engines in small aircraft is limited to a low ceiling level. Here, we propose to significantly extend the ceiling level by introducing an in-cylinder steam reforming system. In this arrangement, the fuel direct-injection assembly comprises of a two-stage process. In the first stage, a blend of methanol and water is injected into the hot previously compressed cylinder charge onto an in-cylinder catalyst. Residual heat is absorbed due to the blend evaporation and the steam-reforming process to produce hydrogen. In the second stage, diesel fuel with a lower ignition temperature than the hydrogen fuel is injected to initiate combustion, while the absorbed heat (from the first stage) is released through the hydrogen oxidation. Essentially, the absorbed heat is exploited to produce extra hydrogen fuel, which increases the cycle efficiency. In this arrangement, the in-cylinder oxygen content is significantly increased due to the additional oxygen atoms that are included in the methanol and in particular in the water molecules. These are released when the methanol and water are decomposed during the steam-reforming process. We show that owing to the addition of the oxygen content in the cylinder, the flight ceiling level can be extended from 5000 to 9000 ft, and that the indicated efficiency can be increase up to 6%. Full article
(This article belongs to the Special Issue Recent Advances in Internal Combustion Engines)
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20 pages, 6745 KiB  
Article
Investigations of Exhaust Emissions from a Combustion Engine under Simulated Actual Operating Conditions in Real Driving Emissions Test
by Monika Andrych-Zalewska, Zdzislaw Chlopek, Jerzy Merkisz and Jacek Pielecha
Energies 2021, 14(4), 935; https://doi.org/10.3390/en14040935 - 10 Feb 2021
Cited by 8 | Viewed by 1599
Abstract
The paper describes the methodology of research of exhaust emissions from a combustion engine under engine states determined by the vehicle actual operation in the RDE test. The processes of quantities determining the vehicle motion and engine states have been recorded, along with [...] Read more.
The paper describes the methodology of research of exhaust emissions from a combustion engine under engine states determined by the vehicle actual operation in the RDE test. The processes of quantities determining the vehicle motion and engine states have been recorded, along with the exhaust emission intensity. Based on the developed research methodology, zero-dimensional characteristics of the processes of the emission intensity have been determined under the conditions of urban, rural and motorway traffic, as well as in the entire test. The authors also determined the average specific distance exhaust emissions under the conditions of urban, rural and motorway traffic, as well as in the entire test. Based on the above results, the unique characteristics of the relation of the average specific distance emissions and the average vehicle speed have been obtained. The obtained characteristics may be used in the modeling of exhaust emissions from motor vehicles under actual traffic conditions. The authors also explored the sensitivity of the average specific distance emissions to the vehicle driving style. Full article
(This article belongs to the Special Issue Recent Advances in Internal Combustion Engines)
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19 pages, 13917 KiB  
Article
The Assessment of Autoignition of Modified Jet Fuels
by Jerzy Merkisz, Ireneusz Pielecha and Anna Łęgowik
Energies 2021, 14(3), 633; https://doi.org/10.3390/en14030633 - 27 Jan 2021
Cited by 3 | Viewed by 1587
Abstract
The condition of the natural environment, including breathable air, indicates that actions are to be taken related to the reduction of exhaust emissions from transport. One of the sectors of transport is aviation. The reduction of emissions is tightly related to the types [...] Read more.
The condition of the natural environment, including breathable air, indicates that actions are to be taken related to the reduction of exhaust emissions from transport. One of the sectors of transport is aviation. The reduction of emissions is tightly related to the types of fuels in this sector of transport. In the paper, the authors propose the application of a new generation of jet fuels. A full exploration of the physicochemical properties of these fuels requires research under actual engine operation. The conducted research pertains to the autoignition of modified jet fuels in terms of the thermodynamic indicators and optical analyses of the early phase of flame development. The investigations were conducted using a Rapid Compression Expansion Machine with a simultaneous recording of images using a high-speed camera. Owing to this technique, the authors could assess the thermodynamic properties and analyze the early flame development processes. The investigations enabled the assessment of fuel properties indicating an increased delay of the autoignition process compared to the reference fuel (diesel fuel). The performed analyses have confirmed a huge role of modern fuels (including HEFA in particular) in contemporary aviation–significant delay of autoignition at a simultaneous significant formation of autoignition spots and high intensification of combustion. Full article
(This article belongs to the Special Issue Recent Advances in Internal Combustion Engines)
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22 pages, 3872 KiB  
Article
Use of Gas Desorption Effect in Injection Systems of Diesel Engines
by Maciej Bajerlein, Wojciech Karpiuk and Rafał Smolec
Energies 2021, 14(1), 244; https://doi.org/10.3390/en14010244 - 05 Jan 2021
Cited by 4 | Viewed by 1924
Abstract
The article presents a concept of improving operation of the engine with the effect of gas desorption from a solution with nucleation of gas bubbles. This concept consists in dissolving gas in diesel fuel until the solution is in equilibrium. At a later [...] Read more.
The article presents a concept of improving operation of the engine with the effect of gas desorption from a solution with nucleation of gas bubbles. This concept consists in dissolving gas in diesel fuel until the solution is in equilibrium. At a later stage, the phenomenon is reversed, and the gas is released from the solution during its injection into the combustion chamber. The purpose of the study is to present the idea of the desorption effect along with a thermodynamic analysis of the process and to study its impact on the operation of a diesel engine. The article also describes the most important features of the injection pump adapted to employ the desorption effect, which is a proprietary, patented solution. The conducted engine preliminary tests concerned the most important parameters of the engine’s operation (indicated pressure course, pressure growth rate, heat release rate, etc.) and the emission of harmful compounds (PM—particulate matter, CO, HC, and NOx—nitrogen oxides). A significant reduction of PM, CO, and HC, with a simultaneous increase in NOx emissions obtained in tests, confirmed that the desorption effect facilitated engine operation. Full article
(This article belongs to the Special Issue Recent Advances in Internal Combustion Engines)
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10 pages, 1477 KiB  
Article
Efficiency at Maximum Power of the Low-Dissipation Hybrid Electrochemical–Otto Cycle
by David Diskin and Leonid Tartakovsky
Energies 2020, 13(15), 3961; https://doi.org/10.3390/en13153961 - 01 Aug 2020
Cited by 18 | Viewed by 2321
Abstract
A novel analytical method was developed for analysis of efficiency at maximum power of a hybrid cycle combining electrochemical and Otto engines. The analysis is based on the low-dissipation model, which relates energy dissipation with energy transfer rate. Efficiency at maximum power of [...] Read more.
A novel analytical method was developed for analysis of efficiency at maximum power of a hybrid cycle combining electrochemical and Otto engines. The analysis is based on the low-dissipation model, which relates energy dissipation with energy transfer rate. Efficiency at maximum power of a hybrid engine operating between two reservoirs of chemical potentials is evaluated. The engine is composed of an electrochemical device that transforms chemical potential to electrical work of an Otto engine that uses the heat generated in the electrochemical device and its exhaust effluent for mechanical work production. The results show that efficiency at maximum power of the hybrid cycle is identical to the efficiency at maximum power of an electrochemical engine alone; however, the power is the product of the electrochemical engine power and the compression ratio of the Otto engine. Partial mass transition by the electrochemical device from the high to the low chemical potential is also examined. In the latter case, heat is generated both in the electrochemical device and the Otto engine, and the efficiency at maximum power is a function of the compression ratio. An analysis performed using the developed method shows, for the first time, that, in terms of a maximal power, at some conditions, Otto cycle can provide better performance that the hybrid cycle. On the other hand, an efficiency comparison at maximum power with the separate Otto-cycle and chemical engine results in some advantages of the hybrid cycle. Full article
(This article belongs to the Special Issue Recent Advances in Internal Combustion Engines)
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