scholarly journals Study of Unsteady Airflow in Muffler and Air Box Equivalent Geometries

2013 ◽  
Author(s):  
Nicolas-Ivan Hatat ◽  
François Lormier ◽  
David Chalet ◽  
Pascal Chesse
Keyword(s):  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Three Dimensional ◽  
Experimental Tests ◽  
Internal Combustion ◽  
Physical Models ◽  
One Dimensional ◽  
1D Modeling ◽  
Air Intake ◽  
And Performance

The Internal Combustion Engines (ICE) are inherently sources of the flow’s unsteadiness in the intake and exhaust ducts. Unsteady flow has a direct impact on the engine’s behavior and performance by influencing the filling and emptying of the cylinder. Air intake boxes as well as muffler geometries, which are very commonly used on the two-wheeled vehicles, have an impact on pressure levels and so, on air filling and performances levels. Thus, the purpose of this paper is to identify and analyze different typical geometries of these elements (air box and muffler) by comparing the test bench results with those obtained by 3D and 1D calculations. In this way, it is possible to establish a methodology for modeling the air box and muffler based on experimental tests and the development of 3D and then 1D model. In a beginning, studies consist in describing the geometry of the air box and muffler using a combination of tubes and simple volumes. During one-dimensional simulations, the gases properties in a volume must be calculated taking into account a method of filling and emptying. Under transient conditions, the pipe element is considered essentially as one-dimensional. The gas dynamic is described by a system of equations: the equations of continuity, momentum and energy. In the three-dimensional case, all tubes and volumes are meshed and solved using various physical models, equations and hypotheses that will be detailed subsequently. The study is performed on a shock tube bench. One of the main points is that this type of experimental test allows to test easily different pressure ratios, different geometries and to measure direct and inverse flow. In this way, the propagation of a shock wave is studied in our different geometries and is compared to the pressure signals obtained with 1D and 3D simulations. Once the 1D modeling is obtained, it must be validated in order to be applied in a simulation for Internal Combustion Engine. Validation will be done by direct comparison of results at each stage to ensure that the models and assumptions used in the calculations are correct.

scholarly journals Real Time Neutron Radiography Applications in Gas Turbine and Internal Combustion Engine Technology

1988 ◽  
Author(s):  
John T. Lindsay ◽  
C. W. Kauffman
Keyword(s):  
Real Time ◽  
Gas Turbine ◽  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Neutron Radiography ◽  
Three Dimensional ◽  
Basic Research ◽  
Internal Combustion ◽  
Turbine Engines ◽  
Gas Turbine Engines

Real Time Neutron Radiography (RTNR) is rapidly becoming a valuable tool for nondestructive testing and basic research with a wide variety of applications in the field of engine technology. The Phoenix Memorial Laboratory (PML) at the University of Michigan has developed a RTNR facility and has been using this facility to study several phenomena that have direct application to internal combustion and gas turbine engines. These phenomena include; 1) the study of coking and debris deposition in several gas turbine nozzles (including the JT8D), 2) the study of lubrication problems in operating standard internal combustion engines and in operating automatic transmissions (1, 2, 3), 3) the location of lubrication blockage and subsequent imaging of the improvement obtained from design changes, 4) the imaging of sprays inside metallic structures in both a two-dimensional, standard radiographic manner (4, 5) and in a computer reconstructed, three-dimensional, tomographic manner (2, 3), and 5) the imaging of the fuel spray from an injector in a single cylinder diesel engine while the engine is operating. This paper will show via slides and real time video, the above applications of RTNR as well as other applications not directly related to gas turbine engines.

Integrated modelling of internal combustion engine intake and exhaust systems

2001 ◽  
Vol 215 (4) ◽  
pp. 495-506 ◽  
Author(s):  
O Chiavola
Keyword(s):  
Internal Combustion Engines ◽  
Gas Flow ◽  
Complex Geometry ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Integrated Modelling ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
One Dimensional ◽  
Exhaust Systems

This paper presents a new method to analyse the unsteady gas flow in both intake and exhaust systems of internal combustion engines. Such a method is based on the simultaneous use of a one-dimensional model applied to describe the phenomena in ducts, together with a lumped parameter scheme to investigate the cylinder or other volume behaviour, coupled with a three-dimensional model, able to guarantee detailed information on flow behaviour in complex geometry, retaining the advantages of all methods, accuracy as well as fast processing and high flow pattern resolution. The description of the one-dimensional model developed with an example of its application is presented. The integrated approach with the coupling procedure is then described. Finally the results of a multicylinder exhaust system simulation are illustrated.

A Multidimensional Model to Simulate Direct Gaseous Fuel Injection in Internal Combustion Engines

2009 ◽  
Author(s):  
L. Andreassi ◽  
A. L. Facci ◽  
S. Ubertini
Keyword(s):  
Internal Combustion Engines ◽  
Fuel Injection ◽  
Combustion Engine ◽  
Combustion Process ◽  
Three Dimensional ◽  
Air Entrainment ◽  
Internal Combustion ◽  
Numerical Results ◽  
Gaseous Fuel ◽  
Injection System

As a consequence of the endless price growing of oil, and oil derivate fuels, automotive industry is experiencing a concerning decreasing in sales. Accordingly, in order to meet customer needs, there is every day a greater interest in solutions for increasing engine efficiency. On the other hand the growing attention to environmental problems leads to increasingly restrictive regulations, such as European EURO 4 and EURO 5. Direct injection of gaseous fuel has emerged to be a high potential strategy to tackle both environmental and fuel economy requirements. However since the electronic gaseous injection technology is rather new for automotive applications, limited experience exists on the optimum configuration of the injection system and the combustion chamber. To facilitate the development of these applications computer models are being developed to simulate gaseous injection, air entrainment and the ensuing combustion. This paper introduces a new method for modelling the injection process of gaseous fuels in multi-dimensional simulations. The proposed model allows holding down grid requirements, thus making it compatible with the three-dimensional simulation of an internal combustion engine. The model is validated and calibrated by comparing numerical results with available experimental data. To highlight the potential applications, some numerical results of the three-dimensional combustion process in a gas engine are presented.

scholarly journals Development of a virtual bench for the analysis of the physical processes of internal combustion engines

2021 ◽  
Vol 2102 (1) ◽  
pp. 012013
Author(s):  
J P Rojas Suárez ◽  
J A Pabón León ◽  
M S Orjuela Abril
Keyword(s):  
Heat Release ◽  
Fuel Consumption ◽  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Maximum Deviation ◽  
Pressure Curve ◽  
Combustion Engines ◽  
Operating Characteristics ◽  
And Performance

Abstract Currently, internal combustion engines face the challenge of reducing fuel consumption and reducing polluting emissions due to their significant impact on the environment. Therefore, it is necessary to use tools that allow us to evaluate the operating characteristics of this type of thermal machines. In the present investigation, the development of a virtual bench was proposed for the analysis of the behavior and performance characteristics of an internal combustion engine for use as a learning tool in higher education students. From the results obtained, it could be demonstrated that the pressure curves of the combustion chamber and the rate of heat release obtained by means of the virtual bench presented a high concordance with the experimental records. The maximum deviation obtained was 5% and 15% for the pressure curve and the heat release rate. Comparing the performance parameters of the brake specific fuel consumption of the engine and energy efficiency, a maximum deviation of 2.96% was shown compared to the real engine. In general, the virtual development bank can describe the behavior of the engine, allowing the characterization of physical phenomena, as well as evaluating the effect of auxiliary technologies such as turbo-compression systems.

Keeping twin turbocharged engine power at flight altitudes

2018 ◽  
Vol 90 (6) ◽  
pp. 906-913 ◽  
Author(s):  
Mohammad Reza Khodaparast ◽  
Mohsen Agha Seyed Mirza Bozorg ◽  
Saeid Kheradmand
Keyword(s):  
Internal Combustion Engine ◽  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Pressure Ratio ◽  
Internal Combustion ◽  
Content Type ◽  
One Dimensional ◽  
Effective Performance ◽  
Different Altitudes ◽  
Engine Power

Purpose The purpose of this paper is the selection and arrangement of turbochargers set for internal combustion engine which could keep engine power in an altitude of up to 12.2 km above sea level. Design/methodology/approach In the current research, the target engine, a one-dimensional four-stroke 1,600 cc piston engine has been simulated and the manufacturer’ results have been validated. Depending on engine size, three proper types of Garret turbochargers GT30, GT25 and GT20 were selected for this engine. Then, the engine and a combination of two turbochargers have been modeled one-dimensionally. A control system was used for regulation of different pressure ratios between the two turbochargers. Findings The parametric analysis shows that using the combination of GT20, GT30 turbochargers with a properly controlled pressure ratio leads to a constant output power with little changes at different altitudes which enable achieving an altitude of 12.2 km for the target engine. Practical implications Adaptation of the internal combustion engine with a twin turbocharger using one-dimensional modeling. Originality/value The one-dimensional analysis provided an overall picture of the effective performance of turbochargers functioning in different altitudes and loads. It presents a new method for adopting of turbochargers set with internal combustion engines for propulsion medium-altitude aircraft.

A Constant-Pressure Model for the Overlap of Chambers in Rotary Internal Combustion Engines

2016 ◽  
Vol 138 (11) ◽  
Author(s):  
Ezequiel J. López ◽  
Carlos A. Wild Cañón ◽  
Sofía S. Sarraf
Keyword(s):  
Internal Combustion Engines ◽  
Constant Pressure ◽  
Combustion Engine ◽  
Flow Direction ◽  
Internal Combustion ◽  
Combustion Engines ◽  
One Dimensional ◽  
Rotary Engines ◽  
Proposed Model ◽  
Reliable Solution

In this work, a constant-pressure model capable to simulate the overlap of chambers in rotary internal combustion engines is proposed. It refers as a chamber overlap when two adjacent chambers are in communication through the same port, which could occur in some rotary internal combustion engines. The proposed model is thermodynamic (or zero-dimensional (0D)) in nature and is designed for application in engine simulators that combine one-dimensional (1D) gasdynamic models with thermodynamic ones. Since the equations of the proposed model depend on the flow direction and on the flow regime, a robust and reliable solution strategy is developed. The model is assessed using a two-dimensional (2D) problem and is applied in the simulation of a rotary internal combustion engine. Results for this last problem are compared with other common approaches used in the simulation of rotary engines, showing the importance of effects such as the interaction between overlapping chambers and the dynamics of the flow.

scholarly journals A design concept of a device for measuring air flow resistance in vehicle filters

2020 ◽  
Author(s):  
Adrian Misztuk
Keyword(s):  
Flow Resistance ◽  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Air Flow ◽  
Engine Performance ◽  
Internal Combustion ◽  
Design Concept ◽  
Compression Ignition Engine ◽  
Intake System ◽  
Air Intake

Internal combustion engines have to be supplied with adequate amounts of fuel and air. The required amount of fuel and air is determined by the engine controller to guarantee that the fuel reaching the cylinder is burned effectively and that the composition of exhaust gas meets standard requirements. The air supplied to an internal combustion engine has to be adequately filtered because impurities reaching the engine can accelerate the wear of engine components. The air intake system features a filtering partition which captures impurities and prevents them from reaching the engine. However, the filtering process decreases the rate at which cylinders are filled with fresh air, which can compromise engine performance. Therefore, effective solutions are needed to ensure that the flow of filtered air does not significantly decrease the volumetric efficiency of cylinders.  This study presents a design concept of a device for measuring pressure in the air intake system in front of and behind the filtering partition. The proposed device can be useful for measuring filter wear. A prototype of the proposed device was built and tested on several air filters. To eliminate throttle valve impacts, the device was tested in a compression ignition engine. The results of the conducted tests demonstrated that the device correctly measured air flow. The conducted measurements also revealed that the presence of impurities in the air filter induced differences in pressure in the air intake system in front of and behind the filtering partition. The maximum air flow resistance in a clogged filter could be even 100% higher than in a brand new filter. W niniejszej pracy przedstawiono koncepcję stanowiska umożliwiającego prowadzenie pomiarów ciśnienia panującego w kanale dolotowym silnika przed i za przegrodą filtracyjną powietrza, które mogą być przydatne przy określaniu stopnia jej zużycia. Dodatkowo zbudowano prototyp urządzenia i w celu weryfikacji poprawności jego działania przeprowadzono za jego pomocą badania przykładowych filtrów. Badania wykonano z użyciem silnika spalinowego o zapłonie samoczynnym. Wyniki pomiarów potwierdzają działanie urządzenia oraz obrazują zależności pomiędzy filtrami o różnym stopniu zużycia. Okazuje się, że maksymalny opór przepływu zużytego wkładu filtracyjnego może być nawet o ok. 100% większy niż w przypadku nowego wkładu filtracyjnego.

A Simple Theory for Pressure Pulses in Exhaust Systems

1964 ◽  
Vol 179 (1) ◽  
pp. 365-394 ◽  
Author(s):  
P. O. A. L. Davies ◽  
M. J. Dwyer
Keyword(s):  
Internal Combustion Engines ◽  
Three Dimensional ◽  
Internal Combustion ◽  
Combustion Engines ◽  
Simple Method ◽  
One Dimensional ◽  
Flow Problems ◽  
Dimensional Flow ◽  
Dimensional Effects ◽  
Pressure Pulses

A simple method is presented for calculating the strength of pressure pulses transmitted through pipes with area changes or in simple branch systems. The method is based on the assumption of one-dimensional flow, otherwise the exact gas relations are employed. A number of examples of typical practical configurations were investigated both theoretically and experimentally and the results compared. With the exception of one or two cases where three-dimensional effects predominate, the agreement between the theory and the measurements was very satisfactory. The application of the theory to flow problems in internal combustion engines is discussed in some detail.

Exploring the Potential Advantages of Light-Weight Valves in Internal Combustion Engines

2006 ◽  
Author(s):  
Jason T. Miwa ◽  
Richard T. Buckley ◽  
Rudolf H. Stanglmaier ◽  
Donald W. Radford
Keyword(s):  
Dynamic Model ◽  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Valve Train ◽  
Spring Stiffness ◽  
Engine Operation ◽  
Valve Spring ◽  
Performance Improvements ◽  
And Performance

This paper presents an investigation into the potential efficiency and performance improvements in an internal combustion engine by changing the mass and stiffness of valve train components, specifically the mass of the valve and the stiffness of the valve spring. Changes in valve mass affect the dynamic response of the valve train, so changes in other components must be made to maintain reliable and efficient engine operation. In order to quantify the potential benefits of lightweight engine valves, a dynamic model of the complete valve train system was developed. This model was experimentally validated on a motored engine in which the valve motion was measured for different combinations of valve mass, spring stiffness and engine speed. This paper describes the development and validation of the dynamic model, and discusses the effects of varying the valve mass and valve spring stiffness. It was found that a 75% reduction in the mass of the valves (as expected through the use of fiber reinforced composites) could reduce the maximum camshaft drive torque and frictional power by about 60–70%.

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.

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