EXPERT SYSTEM APPROACH USING GRAPH REPRESENTATION AND ANALYSIS FOR VARIABLE-STROKE INTERNAL-COMBUSTION ENGINE DESIGN

1990 ◽  
Vol 04 (03) ◽  
pp. 389-408 ◽  
Author(s):  
STEWART N. T. SHEN ◽  
MENG-SANG CHEW ◽  
GHASSAN F. ISSA
Keyword(s):  
Expert System ◽  
Particle Physics ◽  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Graph Representation ◽  
Preliminary Design ◽  
Practical Applications ◽  
Design Alternatives ◽  
Engine Design

Even though AI technology is a relatively new discipline, many of its concepts have already found practical applications. Expert systems, in particular, have made significant contributions to technologies in such fields as business, medicine, engineering design, chemistry, and particle physics. This paper describes an expert system developed to aid mechanical engineering designers in the preliminary design of variable-stroke internal-combustion engines. Variable-stroke engines are more economical in fuel consumption but their design is particularly difficult to accomplish. With the traditional design approach, synthesizing the mechanisms for the design is rather difficult and evaluating the mechanisms is an even more cumbersome and time-consuming effort. Our expert system assists the designer by generating and evaluating a large number of design alternatives represented in the form of graphs. Through the application of structural and design rules obtained from design experts to the graphs, good quality preliminary design configurations of the engines are promptly deduced. This approach can also be used in designing other types of mechanisms.

scholarly journals A review of split-cycle engines

2018 ◽  
Vol 21 (6) ◽  
pp. 897-914 ◽  
Author(s):  
Joshua Finneran ◽  
Colin P Garner ◽  
Michael Bassett ◽  
Jonathan Hall
Keyword(s):  
Thermal Management ◽  
Thermal Efficiency ◽  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Combustion Engines ◽  
Engine Design ◽  
Work Assessment ◽  
In Series ◽  
Management Issues

This article reviews split-cycle internal combustion engine designs. The review includes historical work, assessment of prototypes and discussion of the most recent designs. There has been an abundance of split-cycle engine designs proposed since the first in 1872. Despite this, very few prototypes exist, and no split-cycle engines are reported to be in series production. The few split-cycle prototypes that have been developed have faced practical challenges contributing to limited performance. These challenges include air flow restrictions into the expansion cylinder, late combustion, thermal management issues, and mechanical challenges with the crossover valve actuation mechanism. The main promoted advantage of split-cycle engines is the increased thermal efficiency compared to conventional internal combustion engines. However, an efficiency improvement has not thus far been demonstrated in published test data. The thermodynamic studies reviewed suggest that split-cycle engines should be more efficient than conventional four-stroke engines. Reasons why increased thermal efficiency is not realised in practice could be due to practical compromises, or due to inherent architectural split-cycle engine design limitations. It was found that the number of split-cycle engine patents has increased significantly over recent years, suggesting an increased commercial interest in the concept since the possibility of increased efficiency becomes more desirable and might outweigh the drawbacks of practical challenges.

A methodology for engine design using multi-dimensional modelling and genetic algorithms with validation through experiments

2000 ◽  
Vol 1 (3) ◽  
pp. 229-248 ◽  
Author(s):  
P. K. Senecal ◽  
D. T. Montgomery ◽  
R. D. Reitz
Keyword(s):  
High Speed ◽  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Injection Pressure ◽  
Internal Combustion ◽  
Simultaneous Optimization ◽  
Boost Pressure ◽  
Efficient Design ◽  
Baseline Design ◽  
Engine Design

A methodology for internal combustion engine design has been formulated which incorporates multidimensional modelling and experiments to optimize and simulate direct injection diesel engine combustion and emissions formation. The computer code KIVA-GA performs full-cycle engine simulations within the framework of a genetic algorithm (GA) global optimization code. The methodology is applied to optimize a heavy-duty diesel truck engine. The study simultaneously investigated the effects of six engine input parameters on emissions and performance for a high-speed medium-load operating point. The start of injection (SOI), injection pressure, amount of exhaust gas recirculation (EGR), boost pressure and split injection rate shape were optimized. The convergence of the GA optimization process is demonstrated and the results were compared to those of the experimental optimization study employing a response surface method (RSM), which uses statistically designed experiments to determine an optimum design. In addition, the parameters of the computationally predicted optimum were run experimentally and good agreement was obtained. The potential for ultra-low emissions levels was assessed through additional computational GA runs that included higher maximum EGR levels (up to 50 per cent). The predicted optimum results in significantly lower soot and NOx emissions together with improved fuel consumption compared to the baseline design. The present results indicate that an efficient design methodology has been developed for optimization of internal combustion engines, one that allows simultaneous optimization of a large number of parameters.

scholarly journals Engines of the Future

2015 ◽  
Vol 137 (12) ◽  
pp. 30-35
Author(s):  
Robert M. Wagner
Keyword(s):  
Internal Combustion Engine ◽  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Combustion Process ◽  
Internal Combustion ◽  
Past Century ◽  
Low Temperature Combustion ◽  
Fuel Flexibility ◽  
Engine Design ◽  
Temperature Combustion

This article elaborates the advancement in internal combustion engine technology and explains why internal combustion engines will continue to be integral to the transportation of people and goods for the foreseeable future. The internal combustion engine has seen a remarkable evolution over the past century. Before 1970, the evolution of engine design was driven by quest for performance and increase in octane in the fuel supply. Since then, however, the imperative was the need to meet new emissions and fuel economy regulations. Some game-changing advances in automotive sector in recent years are improvements in engine technologies, sensors, and onboard computing power. This combination of technologies will enable unprecedented control of the combustion process, which in turn will enable real-world implementations of low-temperature combustion and other advanced strategies as well as improved robustness and fuel flexibility. In future, new engine concepts will also blend the best characteristics of both engine types to push the boundaries of efficiency while meeting stringent emissions regulations worldwide.

scholarly journals Laminar Burning Velocity of Biogas-Containing Mixtures. A Literature Review

Processes ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 996
Author(s):  
Venera Giurcan ◽  
Codina Movileanu ◽  
Adina Magdalena Musuc ◽  
Maria Mitu
Keyword(s):  
Gas Turbines ◽  
Internal Combustion Engines ◽  
Fossil Fuels ◽  
Combustion Engine ◽  
Burning Velocity ◽  
Internal Combustion ◽  
Electricity Production ◽  
Engine Fuel ◽  
Laminar Burning Velocity ◽  
Waste Products

Currently, the use of fossil fuels is very high and existing nature reserves are rapidly depleted. Therefore, researchers are turning their attention to find renewable fuels that have a low impact on the environment, to replace these fossil fuels. Biogas is a low-cost alternative, sustainable, renewable fuel existing worldwide. It can be produced by decomposition of vegetation or waste products of human and animal biological activity. This process is performed by microorganisms (such as methanogens and sulfate-reducing bacteria) by anaerobic digestion. Biogas can serve as a basis for heat and electricity production used for domestic heating and cooking. It can be also used to feed internal combustion engines, gas turbines, fuel cells, or cogeneration systems. In this paper, a comprehensive literature study regarding the laminar burning velocity of biogas-containing mixtures is presented. This study aims to characterize the use of biogas as IC (internal combustion) engine fuel, and to develop efficient safety recommendations and to predict and reduce the risk of fires and accidental explosions caused by biogas.

scholarly journals APPLICATION OF A HOLISTIC APPROACH OF HYDROGEN INTERNAL COMBUSTION ENGINE (HICE) BUSSES

2021 ◽  
Vol 1 ◽  
pp. 477-486
Author(s):  
Vahid Douzloo Salehi
Keyword(s):  
Fuel Cell ◽  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Holistic Approach ◽  
Internal Combustion ◽  
Transport Sector ◽  
Driving Mode ◽  
Cell Technology ◽  
Fuel Cell Technology ◽  
Hydrogen Supply

AbstractHydrogen is a promising fuel to fulfil climate goals and future legislation requirements due to its carbon-free property. Especially hydrogen fueled buses and heavy-duty vehicles (HDVs) strongly move into the foreground. In contrast to the hydrogen-based fuel cell technology, which is already in commercial use, vehicles with hydrogen internal combustion engines (H2-ICE) are also a currently pursued field of research, representing a potentially holistic carbon-free drive train. Real applications of H2-ICE vehicles are currently not known but can be expected, since their suitability is put to test in a few insolated projects at this time. This paper provides a literature survey to reflect the current state of H2-ICEs focused on city buses. An extended view to HDVs and fuel cell technology allows to recognize trends in hydrogen transport sector, to identify further research potential and to derive useful conclusion. In addition, within this paper we apply green MAGIC as a holistic approach and discuss Well-to-Tank green hydrogen supply in relation to a H2-ICE city bus. Building on that, we introduce the upcoming Hydrogen-bus project, where tests of H2-ICE buses in real driving mode are foreseen to investigate Tank-to-Wheel.

Effect of Engine Operating Parameters on Combustion and Emission Characteristics

1992 ◽  
Author(s):  
Jiang Lu ◽  
Ashwani K. Gupta ◽  
Eugene L. Keating
Keyword(s):  
Internal Combustion Engine ◽  
Combustion Chamber ◽  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Combustion Process ◽  
Pressure Rise ◽  
Internal Combustion ◽  
Operating Parameters ◽  
Emission Characteristics ◽  
Pollutants Emission

Abstract Numerical simulation of flow, combustion, heat release rate and pollutants emission characteristics have been obtained using a single cylinder internal combustion engine operating with propane as the fuel. The data are compared with experimental results and show excellent agreement for peak pressure and the rate of pressure rise as a function of crank angle. The results obtained for NO and CO are also found to be in good agreement and are similar to those reported in the literature for the chosen combustion chamber geometry. The results have shown that both the combustion chamber geometry and engine operating parameters affects the flame growth within the combustion chamber which subsequently affects the pollutants emission levels. The code employed the time marching procedure and solves the governing partial differential equations of multi-component chemically reacting fluid flow by finite difference method. The numerical results provide a cost effective means of developing advanced internal combustion engine chamber geometry design that provides high efficiency and low pollution levels. It is expected that increased computational tools will be used in the future for enhancing our understanding of the detailed combustion process in internal combustion engines and all other energy conversion systems. Such detailed information is critical for the development of advanced methods for energy conservation and environmental pollution control.

Improving the design of an internal combustion engine with counter pistons

2021 ◽  
pp. 3-6
Author(s):  
Keyword(s):  
Internal Combustion Engine ◽  
Dynamic Characteristics ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Maximum Torque ◽  
Moment Vector ◽  
Engine Design ◽  
Torque Moment ◽  
Dimensional Parameters ◽  
Crank Mechanism

A new layout of a two-cylinder internal combustion engine with counter-pistons is proposed, which increases its efficiency by reducing the pressure angles. The dynamics of the proposed arrangement of a two-shaft crank-slider internal combustion engine, which provides maximum torque moment at maximum gas pressure in the minimum volume of the combustion chamber, is investigated, which reduces the load on the engine design and its weight and dimensional parameters. The research was carried out by comparing the dynamic characteristics of different engines using vector modular models and the KDAM program. Keywords: internal combustion engine, crank mechanism, indicator diagram, dynamic characteristics, torque moment, vector, contour, model, module [email protected]

Computationally Efficient Simulation of Multi-Component Fuel Combustion Using a Sparse Analytical Jacobian Chemistry Solver and High-Dimensional Clustering

2013 ◽  
Author(s):  
Federico Perini ◽  
Anand Krishnasamy ◽  
Youngchul Ra ◽  
Rolf D. Reitz
Keyword(s):  
Reaction Mechanism ◽  
Chemical Kinetics ◽  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Engine Performance ◽  
Internal Combustion ◽  
Point Of View ◽  
High Dimensional ◽  
Computational Point ◽  
Fuel Surrogates

The need for more efficient and environmentally sustainable internal combustion engines is driving research towards the need to consider more realistic models for both fuel physics and chemistry. As far as compression ignition engines are concerned, phenomenological or lumped fuel models are unreliable to capture spray and combustion strategies outside of their validation domains — typically, high-pressure injection and high-temperature combustion. Furthermore, the development of variable-reactivity combustion strategies also creates the need to model comprehensively different hydrocarbon families even in single fuel surrogates. From the computational point of view, challenges to achieving practical simulation times arise from the dimensions of the reaction mechanism, that can be of hundreds species even if hydrocarbon families are lumped into representative compounds, and thus modeled with non-elementary, skeletal reaction pathways. In this case, it is also impossible to pursue further mechanism reductions to lower dimensions. CPU times for integrating chemical kinetics in internal combustion engine simulations ultimately scale with the number of cells in the grid, and with the cube number of species in the reaction mechanism. In the present work, two approaches to reduce the demands of engine simulations with detailed chemistry are presented. The first one addresses the demands due to the solution of the chemistry ODE system, and features the adoption of SpeedCHEM, a newly developed chemistry package that solves chemical kinetics using sparse analytical Jacobians. The second one aims to reduce the number of chemistry calculations by binning the CFD cells of the engine grid into a subset of clusters, where chemistry is solved and then mapped back to the original domain. In particular, a high-dimensional representation of the chemical state space is adopted for keeping track of the different fuel components, and a newly developed bounding-box-constrained k-means algorithm is used to subdivide the cells into reactively homogeneous clusters. The approaches have been tested on a number of simulations featuring multi-component diesel fuel surrogates, and different engine grids. The results show that significant CPU time reductions, of about one order of magnitude, can be achieved without loss of accuracy in both engine performance and emissions predictions, prompting for their applicability to more refined or full-sized engine grids.

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