Submit to Energies Review for Energies Propose a Special Issue

Journal Menu

Journal Browser

Combustion Engine In-Cylinder Flow

Print Special Issue Flyer
Special Issue Editors
Special Issue Information
Keywords
Published Papers

A special issue of Energies (ISSN 1996-1073). This special issue belongs to the section "I2: Energy and Combustion Science".

Deadline for manuscript submissions: closed (31 August 2023) | Viewed by 8928

Share This Special Issue

Special Issue Editors

Dr. Enhua Wang

E-Mail Website
Guest Editor

School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, China
Interests: diesel engines; internal combustion engines; engineering thermodynamics; waste heat recovery; combustion simulation
Special Issues, Collections and Topics in MDPI journals

Prof. Dr. Jie Liu

E-Mail Website
Guest Editor

Department of Power Mechanical Engineering, Beijing Jiaotong University, Beijing 100044, China
Interests: fundamental combustion theory; combustion in international combustion engines

Special Issue Information

Dear Colleagues,

The Guest Editors are inviting submissions to a Special Issue of Energies on the topic “Combustion Engine In-cylinder Flow”. Air flow organization and air fuel mixing optimization are extremely important for the performance improvement and emission control of internal combustion engines. There have been many emerging techniques for engine in-cylinder flow design and modeling in recent years. Moreover, new approaches have been invented to measure the in-cylinder flow of combustion engines. Hence, the main gas motions in cylinders such as turbulence, swirl, squish, and tumble have been studied comprehensively.

This Special Issue will deal with technology progress and novel approaches for in-cylinder gas motion optimization of combustion engines. Topics of interest for publication include, but are not limited to:

Four-stroke engines;
Spark-ignition engines;
Compression-ignition engines;
Cycle-to-cycle variations；
In-cylinder flow field analysis;
Combustion chamber designs;
Direct numerical simulations;
Large-eddy simulations;
Air-fuel mixture formation;
Stratified charge;
Exhaust gas recirculation;
Valve timing;
Direct injection.

Dr. Enhua Wang
Dr. Jie Liu
Guest Editors

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
spark ignition
compression ignition
turbulence
in-cylinder flow
air-fuel mixing
particle image velocimetry
cycle-to-cycle variations
machine learning
swirl
squish
tumble
lean-burn
optical engine
proper orthogonal decomposition

Published Papers (6 papers)

Download All Papers

Order results

Result details

Show export options Show export options

Select all

Export citation of selected articles as:

Research

Jump to: Review

29 pages, 11541 KiB

Open AccessArticle

Investigation of Flow Fields Emanating from Two Parallel Inlet Valves Using LES, PIV, and POD

by Jana Hoffmann, Walter Vera-Tudela, Niklas Mirsch, Dario Wüthrich, Bruno Schneider, Marco Günther, Stefan Pischinger, Daniel A. Weiss and Kai Herrmann

Energies 2023, 16(19), 6917; https://doi.org/10.3390/en16196917 - 30 Sep 2023

Viewed by 1070

Abstract

Understanding cycle-to-cycle variations (CCV) is of practical importance for the combustion of fossil and renewable fuels, as increasingly stringent emission regulations require reductions in the negative effects of such variations. The subject of this study is the flow around inlet valves, since oscillations of such inlet flows affect the flow structure in the cylinder and are thus one of the causes of CCV. To this end, a parametric analysis of the influences of the mass flow rate and valve lift of two parallel engine intake valves on the flow structures is performed. This follows on from an earlier similar study where the flow around a single intake valve was investigated. To analyse the flow behaviour and, in particular, the interactions of the flow leaving these two valves, an optical test rig for 2D particle image velocimetry (PIV) and a large eddy simulation (LES) are used. Proper orthogonal decomposition (POD), together with a quadruple decomposition and the Reynolds stress transport equations, are used to study the turbulence phenomena. The PIV and LES results are in good agreement with each other. The detailed LES analysis of the flow structures shows that, for small valve lifts, the flow separates along the whole perimeter of the intake valve, and for larger valve lifts, the flow escapes only to one side. This is, for combustion engines with the tumble concept, the stage at which the tumble movement develops. Moreover, the flow structures are strongly influenced by the valve lift, while they are unaffected by the variation in the mass flow. The turbulent kinetic energy in the flow field increases quadratically with a decreasing valve lift and increasing mass flow. The large, high-energetic flow structures are particularly dominant near the jet, and the small, low-energetic structures are homogeneously distributed within the flow field. The specific Reynolds stress transport equation shows the limitations of two-dimensionality and large timesteps in the PIV results and the limitations of the LES model. Full article

(This article belongs to the Special Issue Combustion Engine In-Cylinder Flow)

► Show Figures

Figure 1

15 pages, 3987 KiB

Open AccessArticle

Glycerol as an Anti-Knock Additive and Secondary Fuel as a Substitute for Gasoline-Based Fuels for the IC Engine

by Stanislaw Szwaja, Michal Gruca, Michal Pyrc and Romualdas Juknelevičius

Energies 2023, 16(13), 4940; https://doi.org/10.3390/en16134940 - 25 Jun 2023

Cited by 1 | Viewed by 862

Abstract

The article discusses the possibility of using glycerol as an additive to the engine fuel in order to reduce the tendency of combustion knock, and thus to increase the octane number of a given fuel. Experimental tests were carried out on the UIT-85 research engine with a variable compression ratio from eight to eleven to test the intensity of the knock. The completely renewable fuel—the blend of glycerol with butanol in the ratio of 25 and 75%, respectively—was tested. A comparative analysis of the knock intensity was conducted with gasoline 95 and N-butanol tested as reference fuels. The developed method for knock analysis using the proposed knock indicator was also presented. The experimental results proved the proposed blend of N-butanol and glycerol reduces the knock intensity by more than 50% in the spark-ignition engine at a compression ratio of 10, maintaining engine performance at a similar level as it was for a gasoline-fueled engine. The results confirmed the thesis on the reduction of knock intensity when adding glycerol to N-butanol. Full article

(This article belongs to the Special Issue Combustion Engine In-Cylinder Flow)

► Show Figures

Figure 1

18 pages, 4216 KiB

Open AccessArticle

Effects of Hydrogen Addition on Premixed Combustion of Kerosene in SI Engine

by Yuxuan Zhao, Enhua Wang and Zhicheng Shi

Energies 2023, 16(10), 4216; https://doi.org/10.3390/en16104216 - 20 May 2023

Viewed by 954

Abstract

Spark ignition (SI) engines fueled with kerosene have broad application prospects in unmanned aviation vehicles. The knock phenomenon of kerosene in SI engines is a huge challenge, leading to a much lower power output than gasoline engines. In this context, the combustion characteristics of kerosene blending with hydrogen are analyzed numerically regarding the working conditions of an SI engine. First, the ignition delay time of a kerosene/hydrogen mixture is estimated for temperatures of 600–1000 K and pressures of 15–35 bar using the Tay mechanism. The effects of hydrogen addition are evaluated with a ratio of 0–0.4. The sensitivities of the main reactions that affect the ignition delay time are discussed. Then, the laminar flame speed is predicted using the HYCHEM-SK mechanism, and the effects of hydrogen addition on the net reaction rates of the main reactions are analyzed. The results indicate that the ignition delay time is shortened and the laminar flame speed is increased as the hydrogen addition ratio rises. Meanwhile, the ignition delay time decreases except for the NTC range, and the laminar flame speed increases evidently as the temperature rises. In addition, the ignition delay time decreases obviously as the pressure increases with a temperature greater than 750 K. However, the laminar flame speed declines at 600 K and 800 K, while an opposite trend exhibits at 1000 K as the pressure rises. The laminar flame speed increases by 23.85–24.82%, while the ignition delay time only decreases by 4.02–3.59% at 1000 K as the hydrogen addition ratio rises from 0 to 0.4, which will be beneficial for knock suppression. Full article

(This article belongs to the Special Issue Combustion Engine In-Cylinder Flow)

► Show Figures

Figure 1

31 pages, 17473 KiB

Open AccessArticle

Flow Field Investigation of a Single Engine Valve Using PIV, POD, and LES

by Jana Hoffmann, Niklas Mirsch, Walter Vera-Tudela, Dario Wüthrich, Jorim Rosenberg, Marco Günther, Stefan Pischinger, Daniel A. Weiss and Kai Herrmann

Energies 2023, 16(5), 2402; https://doi.org/10.3390/en16052402 - 2 Mar 2023

Cited by 2 | Viewed by 1844

Abstract

Due to stringent emission regulations, it is of practical significance to understand cycle-to-cycle variations in the combustion of fossil or renewable fuels to reach future emission regulations. The present study aims to conduct a parametric investigation to analyse the influence of the valve lift and different mass flows of an inlet valve of the test engine “Flex-OeCoS” on the flow structures. To gain a deeper understanding of the flow behaviour, an optical test bench for 2D Particle Image Velocimetry (PIV) and a Large Eddy Simulation (LES) are used. Turbulence phenomena are investigated using Proper Orthogonal Decomposition (POD) with a quadruple decomposition and the Reynolds stress transport equation. The results show good agreement between the PIV and LES. Moreover, the main flow structures are primarily affected by valve lift while being unaffected by mass flow variation. The turbulent kinetic energy within the flow field increases quadratically to the mass flow and to the decreasing valve lift, where large high-energetic flow structures are observed in the vicinity of the jet and small low-energetic structures are homogeneously distributed within the flow field. Furthermore, the convective flux, the turbulent diffusive flux, the rate of change, and the production of specific Reynolds stress are the dominant terms within the specific Reynolds stress transport equation. Full article

(This article belongs to the Special Issue Combustion Engine In-Cylinder Flow)

► Show Figures

Figure 1

21 pages, 4394 KiB

Open AccessArticle

Analysis of the Exhaust Emissions of Hybrid Vehicles for the Current and Future RDE Driving Cycle

by Kinga Skobiej and Jacek Pielecha

Energies 2022, 15(22), 8691; https://doi.org/10.3390/en15228691 - 19 Nov 2022

Cited by 6 | Viewed by 1561

Abstract

Hybrid vehicles account for the largest share of new motor vehicle sales in Europe. These are vehicles that are expected to bridge the technological gap between vehicles with internal combustion engines and electric vehicles. Such a solution also makes it possible to meet the limits of motor vehicle emissions, at a time when it is particularly important to test them under actual traffic conditions. This article analyzes the impact of the length of the test routes in relation to current, but also future regulations of approval standards. Three routes of post-phase composition (urban, rural, motorway) with lengths of about 30, 16 and 8 km were selected for the study. Measurements of the main emission components were made using portable emission measurement systems (PEMS), and exhaust emissions were determined using the moving average window (MAW) method. Analysis of the obtained results led to the conclusion that the current requirements for the RDE test (in particular, the duration of the test) enforce a length of each part of 32 km. Reducing the test to 60–90 min causes the individual phases to last 16 km, and the main advantage of such a solution is the very strong influence of the cold start phase on the emission results in the urban phase. Future declarations by lawmakers to drastically reduce the length of the test phases to 8 km will force hybrid vehicles to be tested largely using the internal combustion engine. This will be the right thing to do, especially in the urban phase, as now in addition to a significant reduction in the engine warm-up phase, manufacturers will have to take into account that such an engine thermal condition can also occur in the rural phase. Full article

(This article belongs to the Special Issue Combustion Engine In-Cylinder Flow)

► Show Figures

Figure 1

Review

Jump to: Research

20 pages, 2349 KiB

Open AccessReview

A Review on the Preliminary Design of Axial and Radial Turbines for Small-Scale Organic Rankine Cycle

by Enhua Wang and Ningjian Peng

Energies 2023, 16(8), 3423; https://doi.org/10.3390/en16083423 - 13 Apr 2023

Cited by 3 | Viewed by 1961

Abstract

Organic Rankine cycle (ORC) is an effective technology to harness low-grade energy. Turbine, as a key component of ORC, takes advantages of its high efficiency and compact size compared with other expanders. Currently, developing suitable turbines with a high performance and a low cost is one of the bottlenecks for wide applications of various ORCs. In this context, technical progress on radial inflow turbines (RITs), axial turbines (ATs), and radial outflow turbines (ROTs) is introduced, and loss models used in the preliminary design are compared, especially for small-scale ORCs. RIT is recommended for medium and small ORCs with an expansion pressure ratio of <10. The power outs and rotational speeds of the designed RITs spanned the ranges of 9.3–684 kW and 3000–114,000 r/min with an efficiency of 56.1–91.75%. In comparison, the power outputs and speeds of ATs were 3–2446 kW and 3000–91,800 r/min with an efficiency of 63–89.1%. AT is suitable for large-scale ORCs with a power output of greater than hundreds of kW. However, AT with impulse stages is feasible for small-scale ORCs when the pressure ratio is high, and the mass flow rate is small. The power outputs of the designed ROTs were relatively small, at 10–400 kW with a speed of 7200–42,700 r/min and an efficiency of 68.7–85%. For organic working fluids with a large expansion pressure ratio, ROT might be employed. Conventional mean-line models may neglect the effects of supersonic flow, which will be encountered in many ORC turbines. Therefore, adequate models for supersonic expansion loss and shock loss need to be added. Meanwhile, a proper multivariable optimization algorithm such as a gradient-based or stochastic search method should be selected. Finally, the challenges and potential research directions are discussed. The outcomes can provide some insights for the development of ORC turbines and the optimization of ORC systems. Full article

(This article belongs to the Special Issue Combustion Engine In-Cylinder Flow)

► Show Figures

Journal Menu

Journal Browser

Combustion Engine In-Cylinder Flow

Share This Special Issue

Special Issue Editors

Special Issue Information

Keywords

Published Papers (6 papers)

Research

Review

Further Information

Guidelines

MDPI Initiatives

Follow MDPI