scholarly journals Overall focus on research, including – Fusion of measurement and numerical analysis using weak flame phenomenon in micro combustion system

Impact ◽  
2020 ◽  
Vol 2020 (4) ◽  
pp. 62-64
Author(s):  
Kaoru Maruta ◽  
Hisashi Nakamura ◽  
Youhi Morii ◽  
Takuya Tezuka
Keyword(s):  
Internal Combustion Engines ◽  
High Fidelity ◽  
Combustion Engines ◽  
Combustion System ◽  
Chemical Reaction Kinetics ◽  
Complex Chemical ◽  
Flame Dynamics ◽  
Wide Range ◽  
Complex Chemical Reactions ◽  
Combustion Processes

To achieve highly efficient internal combustion engines, it is essential that the fuel and air mixtures in cylinder burn rapidly without making undesired 'knocking' phenomena. Fuel reactions should be fast enough for attaining sufficiently fast exothermic combustion for power output but simultaneously, it should be durable to the undesired knocking, he notes. It is essential to clarify both ignition-related fuel reactivity and combustion processes that are governed by flame dynamics under intense turbulence. Obtained knowledge should be used for designing combustion phenomena. Dr Karou Maruta from the Institute of Fluid Science at Tohoku University is an expert in flame dynamics. Maruta and his team have been conducting a wide range of practical and theoretical experiments of weak flames in MFR ultimately for practical engine applications. They are looking to address the modelling capabilities of complex chemical reactions. In order to achieve this, the team is attempting to develop high fidelity chemical reaction kinetics, as well as intelligent computational methods.

scholarly journals Fuel Cells: The Next Evolution

MRS Bulletin ◽  
2005 ◽  
Vol 30 (8) ◽  
pp. 581-586 ◽  
Author(s):  
Robert W. Lashway
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Internal Combustion Engines ◽  
Materials Science ◽  
Electrical Conductance ◽  
Electrical Energy ◽  
Pure Oxygen ◽  
Combustion Engines ◽  
Hydrogen Fuel ◽  
Wide Range

AbstractThe articles in this issue of MRS Bulletin highlight the enormous potential of fuel cells for generating electricity using multiple fuels and crossing a wide range of applications. Fuel cells convert chemical energy directly into electrical energy, and as a powergeneration module, they can be viewed as a continuously operating battery.They take in air (or pure oxygen, for aerospace or undersea applications) and hydrocarbon or hydrogen fuel to produce direct current at various outputs. The electrical output can be converted and then connected to motors to generate much cleaner and more fuelefficient power than is possible from internal combustion engines, even when combined with electrical generators in today's hybrid engines. The commercialization of these fuel cell technologies is contingent upon additional advances in materials science that will suit the aggressive electrochemical environment of fuel cells (i.e., both reducing an oxidizing) and provide ionic and electrical conductance for thousands of hours of operation.

scholarly journals Analysis of thermodynamic parameters in spark ignition VCR engine

2019 ◽  
Vol 294 ◽  
pp. 05001
Author(s):  
Patryk Urbański ◽  
Maciej Bajerlein ◽  
Jerzy Merkisz ◽  
Andrzej Ziółkowski ◽  
Dawid Gallas
Keyword(s):  
Thermodynamic Parameters ◽  
Motion Analysis ◽  
Internal Combustion Engines ◽  
Initial Conditions ◽  
Combustion Process ◽  
Internal Combustion ◽  
3D Models ◽  
Spark Ignition ◽  
Combustion Engines ◽  
Combustion Processes

3D models of Szymkowiak and conventional engines were created in the Solidworks program. During the motion analysis, the characteristics of the piston path were analyzed for the two considered engine units. The imported file with the generated piston routes was used in the AVL Fire program, which simulated combustion processes in the two engines with identical initial conditions. The configurations for two different compression ratios were taken into account. The basic thermodynamic parameters occurring during the combustion process in internal combustion engines were analyzed.

A Theoretical Approach to the Combustion of Fuel-Alcohol Blends

1985 ◽  
Vol 107 (4) ◽  
pp. 902-907 ◽  
Author(s):  
G. Cau ◽  
M. P. Pelagagge
Keyword(s):  
Total Energy ◽  
Theoretical Investigation ◽  
Theoretical Approach ◽  
Total Mass ◽  
Internal Combustion Engines ◽  
Combustion Temperature ◽  
Analytical Procedure ◽  
Combustion Engines ◽  
Constant Mass ◽  
Wide Range

This paper is concerned with the results of a theoretical investigation on combustion of traditional fuel and alcohol blends. An analytical procedure has been developed which examines three different hypotheses for introducing the alcohol: constant mass of primary fuel, constant total energy of fuel, and constant total mass of fuel. The procedure has been applied to combustion at constant volume varying over a wide range of air-fuel ratios, percentage of alcohol, and combustion temperature. The results obtained, of particular interest for reciprocating internal combustion engines, indicate that as far as energy and emissions are concerned, the effects of alcohol on combustion depend strongly on the hypothesis adopted for fueling the alcohol.

scholarly journals A design tool for the performances comparison of innovative energy systems for naval applications

2019 ◽  
Vol 113 ◽  
pp. 02005
Author(s):  
D. Rattazzi ◽  
M. Rivarolo ◽  
T. Lamberti ◽  
L. Magistri
Keyword(s):  
Gas Turbines ◽  
Internal Combustion Engines ◽  
Energy Systems ◽  
Design Tool ◽  
Pollutant Emissions ◽  
Combustion Engines ◽  
Wide Range ◽  
Storage Technologies ◽  
Market Solutions ◽  
And Storage

This paper aims to develop a tool for the performances comparison of innovative energy systems on board ships, both for concentrated and distributed generation applications. In the first part of the study, the tool database has been developed throughout a wide analysis of the available market solutions in terms of energy generation devices (i.e. fuel cells, internal combustion engines, micro gas turbines), fuels (hydrogen, natural gas, diesel) and related storage technologies. Many of these data have been collected also thanks to the laboratory experience of the authors’ research group on different innovative energy systems. From the database, a wide range of maps has been created, correlating costs, volumes, weights and emissions with the installed power and the operational hours required, given by the user as input. The tool highlights the best solution according to the different relevance chosen by the user for each key parameter (i.e. costs, volumes, emissions). In the second part, two different case studies are presented in order to underline how the installed power, the different ship typology and the user requirements affect the choice of the best solution. It is worth noting that the methodology has a general value, as the tool can be applied to both the design of new ships, and to the retrofit of already existing ships in order to respect new requirements (e.g. more and more stringent normative in terms of pollutant emissions in ports and restricted areas). Furthermore, the database can be easily extended to other generation and storage technologies.

scholarly journals Development and Validation of a Reduced DME Mechanism Applicable to Various Combustion Modes in Internal Combustion Engines

2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
Gregory T. Chin ◽  
J.-Y. Chen ◽  
Vi H. Rapp ◽  
R. W. Dibble
Keyword(s):  
Internal Combustion Engines ◽  
Internal Combustion ◽  
Combustion Engines ◽  
Detailed Mechanism ◽  
Reduced Mechanism ◽  
Hcci Combustion ◽  
Combustion Modes ◽  
Reduced Chemistry ◽  
Wide Range ◽  
Development And Validation

A 28-species reduced chemistry mechanism for Dimethyl Ether (DME) combustion is developed on the basis of a recent detailed mechanism by Zhao et al. (2008). The construction of reduced chemistry was carried out with automatic algorithms incorporating newly developed strategies. The performance of the reduced mechanism is assessed over a wide range of combustion conditions anticipated to occur in future advanced piston internal combustion engines, such as HCCI, SAHCCI, and PCCI. Overall, the reduced chemistry gives results in good agreement with those from the detailed mechanism for all the combustion modes tested. While the detailed mechanism by Zhao et al. (2008) shows reasonable agreement with the shock tube autoignition delay data, the detailed mechanism requires further improvement in order to better predict HCCI combustion under engine conditions.

scholarly journals A research into a gasoline HCCI engine

2010 ◽  
Vol 140 (1) ◽  
pp. 3-13
Author(s):  
Jacek HUNICZ ◽  
Andrzej NIEWCZAS ◽  
Paweł KORDOS
Keyword(s):  
Internal Combustion Engines ◽  
Fuel Injection ◽  
Injection Timing ◽  
Exhaust Gas ◽  
Combustion Engines ◽  
Hcci Combustion ◽  
Permissible Range ◽  
Wide Range ◽  
Gas Recirculation ◽  
Direct Fuel Injection

Homogeneous charge compression ignition (HCCI) is nowadays a leading trend in the development of gasoline internal combustion engines. The application of this novel combustion system will allow to comply with future legislations concerning the exhaust emissions including carbon dioxide. This paper presents a design and implementation of a research engine with a direct fuel injection and the capability of HCCI combustion via an internal gas recirculation and a negative valves overlap (NVO). The technical approach used in the engine allowed an autonomous HCCI operation at variable loads and engine speeds without the need of a spark discharge. Experiments were conducted at a wide range of valve timings providing data which allowed an assessment of a volumetric efficiency and exhaust gas recirculation (EGR) rate. Permissible range of air excess coefficient, providing stable and repeatable operation has also been identified. The use of direct gasoline injection benefited in the improvement of the start of the combustion (SOC) and heat release rate control via the injection timing.

scholarly journals A Numerical Exploration of Engine Combustion Using Toluene Reference Fuel and Hydrogen Mixtures

2021 ◽  
Vol 312 ◽  
pp. 07003
Author(s):  
Alessio Barbato ◽  
Valentina Pessina ◽  
Massimo Borghi
Keyword(s):  
Internal Combustion Engines ◽  
Laminar Flame ◽  
Pure Hydrogen ◽  
Combustion Engines ◽  
Feeding System ◽  
Numerical Exploration ◽  
Wide Range ◽  
Engine Combustion ◽  
Hydrogen Mixtures ◽  
Computational Fluid Dynamics Cfd

Hydrogen-fueled internal combustion engines (H2ICEs) are capable of operating over a wide range of equivalence ratios: from ultra-lean mode to stoichiometric conditions. However, they provide maximum thermal efficiency and minimum NOx emissions if operated lean. Although NOx is produced, H2ICEs generate little or no CO, CO2, SO2, HC, or PM emissions. The main limitation to pure hydrogen fueling is power density. To overcome such an issue, mixtures of gasoline and hydrogen can be exploited, with small modifications to the engine feeding system. Due to the peculiar characteristics of hydrogen (in terms of thermophysical properties, molecular weight and propagating flame characteristics) care must be adopted when trying to address combustion using computational fluid dynamics (CFD) tools. In this work, we simulate the combustion of mixtures of toluene reference fuel (TRF) and hydrogen under largely different ratios. To simplify the problem, liquid and gaseous injections are neglected, and a premixed mixture at the inlet of the CFD domain is imposed. Due to the different laminar flame speeds of the mixture components, mass-fraction weighted in-house correlations based on chemical kinetics simulations are adopted. Outcomes are compared with those obtained using standard correlations and mixing rules available in most commercial CFD packages.

scholarly journals Renewable Pulverized Biomass Fuel for Internal Combustion Engines

Processes ◽  
2020 ◽  
Vol 8 (4) ◽  
pp. 465
Author(s):  
Ashraf Elfasakhany ◽  
Mishal Alsehli ◽  
Bahaa Saleh ◽  
Ayman A. Aly ◽  
Mohamed Bassuoni
Keyword(s):  
Rate Constants ◽  
Internal Combustion Engines ◽  
Renewable Energy Sources ◽  
Internal Combustion ◽  
Solid Particles ◽  
Combustion Engines ◽  
Modeling Tools ◽  
Wide Range ◽  
New Phenomena ◽  
Powder Combustion

Biomass is currently one of the world’s major renewable energy sources. Biomass in a powder form has been recently proposed as the most encouraging of biomass contours, especially because it burns like a gas. In the current study, biomass powder was examined, for the first time, as a direct solid fuel in internal combustion engines. The aim of the current study was to investigate modeling tools for simulation of biomass powder in combustion engines (CE). The biomass powder applied was in a micro-scale size with a typical irregular shape; the powder length was in the range of 75−5800 μm, and the diameter was in the range 30−1380 μm. Different mechanisms for biomass powder drying and devolatilization/gasification were proposed, including different schemes’ and mechanisms’ rate constants. A comparison between the proposed models and experiments was carried out and results showed good matching. Nevertheless, it is important that a biomass powder simulation addresses overlapping/complicated sub-process. During biomass powder combustion, tar was shown to be formed at a rate of 57 wt.%, and, accordingly, the formation and thermal decomposition of tar were modelled in the study, with the results demonstrating that the tar was formed and then disintegrated at temperatures between 700 and 1050 K. Through biomass powder combustion, moisture, tar, and gases were released, mostly from one lateral of particles, which caused ejection of the solid particles. These new phenomena were investigated experimentally and modeled as well. Results also showed that all the proposed models, along with their rate constants, activation energies, and other models’ parameters, were capable of reproducing the mass yields of gases, tar, and char at a wide range of working temperatures. The results showed that the gasification/devolatilization model 3 is somewhat simple and economical in the simulation/computation scheme, however, models 1 and 2 are rather computationally heavy and complicated.

STAND FOR RUNNING AND TESTING OF LOW POWER MOBILE FARM MACHINERY ENGINES

2016 ◽  
Vol 1 (2) ◽  
pp. 51-53 ◽  
Author(s):  
Иншаков ◽  
Aleksandr Inshakov ◽  
Байков ◽  
Dmitriy Baykov ◽  
Десяев ◽  
...  
Keyword(s):  
Low Power ◽  
Internal Combustion Engine ◽  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Internal Combustion ◽  
High Energy ◽  
Combustion Engines ◽  
Farm Machinery ◽  
Three Phase ◽  
Wide Range

The purpose of research is to improve the quality of production and repair internal low-power mobile farm combustion engines. To achieve this goal it was suggested to carry out running and testing the engines of small tools and equipment in specialized economical braking stands. The design of such stand, consisting of internal combustion engine, connected crank shaft with asynchronous electric machine with wound rotor, connected to the three-phase network, and matrix converter frequency included in the three-phase electrical network and consisting of nine bidirectional transistor switches, which receive signals space-vector control with automatic control system connected with the test equipment on the basis of a personal computer on which the signals from the sensors mounted on the internal combustion engine is also coming. This stand design for running and testing of internal combustion engines of mobile low power farm machinery is technically easy to manufacture and cost-effective to use. In addition, the design feature of the proposed technical solution is characterized by high energy efficiency and reliability, small dimensions and weight parameters, and wide range of speed control asynchronous machine with wound rotor.

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