A study on the high pressure EGR transport and application to the dispersion among cylinders in automotive engines

The objective of this study is to explore the limits of a one-dimensional model to predict the movement and mixing of the air and exhaust gases recirculation (EGR) flows in compact intake manifolds of recent automotive engines. In particular, the high pressure EGR loop configuration is evaluated in this study from the perspective of the EGR dispersion among cylinders. The experimental work includes the use of a fast CO2 tracking system that provides crank-angle resolved results in six locations of the intake manifold together with the acquisition of the time-averaged CO2 concentration in all the intake pipes (eight locations) to evaluate the EGR dispersion empirically. A specific system was developed to inject the EGR in three locations of the intake manifold in a flexible way to modify the dispersion. Up to 29 engine running conditions defined by engine speed, engine torque and EGR rate, spanning the entire engine map, including full load operation, were evaluated. A one-dimensional engine model was built to detect the limits in reproducing the EGR transport in the intake manifold and quantify the accuracy when predicting the dispersion among cylinders. The study concludes that the predicted EGR rate in the cylinders may differ up to 75% from the experimental measurement at low engine averaged EGR rate. The model prediction improves to differences lower than 40% in EGR rate per cylinder if the engine operating points with an EGR rate lower than 10% are excluded. In this situation, 80% of the predicted in-cylinder EGR rates have differences lower than 25% when compared to experiments.

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Modeling and Validation of Automotive Engines for Control Algorithm Development

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.2896525 ◽

1992 ◽

Vol 114 (2) ◽

pp. 278-285 ◽

Cited By ~ 96

Author(s):

J. J. Moskwa ◽

J. K. Hedrick

Keyword(s):

Flow Rate ◽

Control Algorithm ◽

Front Wheel ◽

Intake Manifold ◽

Algorithm Development ◽

Automotive Engine ◽

Engine Model ◽

Automotive Engines ◽

Fuel Flow ◽

Fuel Delivery

There is considerable interest in coordinated automotive engine/transmission control to smooth shifts, and for traction control of front wheel vehicles. This paper outlines a nonlinear dynamic engine model of a port fuel-injected engine, which can be used for control algorithm development. This engine model predicts the mean engine brake torque as a function of the engine controls (i.e., throttle angle, spark advance, fuel flow rate, and exhaust gas recirculation (E. G. R.) flow rate). The model has been experimentally validated for a specific engine, and includes: • intake manifold dynamics, • fuel delivery dynamics, and • process delays inherent in the four-stroke engine. This model is used in real time within a control algorithm, and for system simulation. Also, it is flexible enough to represent a family of spark ignition automotive engines, given some test and/or simulation data for setting parameters.

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Quasi-one-dimensional magnetic properties of NiNb2−xVxO6 compounds synthesized at high pressure in a nonstandard columbite-type structure

Physical Review B ◽

10.1103/physrevb.103.094409 ◽

2021 ◽

Vol 103 (9) ◽

Author(s):

J. Peña ◽

M. A. Gusmão ◽

O. Isnard

Keyword(s):

High Pressure ◽

Magnetic Properties ◽

Type Structure ◽

One Dimensional

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Comparison of Diesel Engine Vibroacoustic Properties Powered by Bio and Standard Fuel

Energies ◽

10.3390/en14051478 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1478

Author(s):

Radoslaw Wrobel ◽

Gustaw Sierzputowski ◽

Zbigniew Sroka ◽

Radostin Dimitrov

Keyword(s):

Alternative Fuels ◽

Internal Combustion Engines ◽

Combustion Process ◽

Significant Other ◽

Engine Torque ◽

Engine Model ◽

Vehicle Operation ◽

History Of ◽

Profile Changes ◽

The Time Domain

Alternative fuels appeared soon after the first internal combustion engines were designed. The history of alternative fuels is basically as long as the history of the automotive industry. Initially, fuels whose physicochemical properties allowed for a change in parameters of the combustion process in order to achieve greater efficiency and reliability were searched for. Nowadays, there are significantly more variables; in addition to the above mentioned parameters, alternative fuels are being sought that will ensure environmental protection during vehicle operation and improve the ergonomics of use. This article outlines the results of the authors’ own comparative tests of vibrations of a vibroacoustic character. Based on a popular engine model, the vibration–acoustic responses of a system powered by two types of fuel, namely, diesel and biodiesel (B10), are compared. The research consists of comparing vibrations in both time and frequency domains. In the case of the time domain, the evaluation was performed with vibrations as a function of engine torque and speed. In the case of frequency analysis, the focus was on changes in the frequency response for the tested fuels. The research shows that the profile of vibroacoustic vibrations changes in the case of biodiesel power supply in relation to standard fuel. The vibration profile changes significantly as a function of speed and only slightly in relation to the engine load. The results presented in this article show different vibroacoustic responses of an engine powered by diesel and biodiesel; the change is minor for lower speeds but significant (other harmonics are dominant) for higher speeds (changes in the dominant harmonic magnitude of up to 10% at a crankshaft speed of 3000 rpm).

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An Analysis of Coupled Multicomponent Diffusion in Interstitial Tissue

Journal of Biomechanical Engineering ◽

10.1115/1.2895715 ◽

1994 ◽

Vol 116 (2) ◽

pp. 164-171 ◽

Cited By ~ 9

Author(s):

P. D. Schreuders ◽

K. R. Diller ◽

J. J. Beaman ◽

H. M. Paynter

Keyword(s):

Multicomponent Diffusion ◽

Frequency Parameter ◽

Interstitial Tissue ◽

Specific System ◽

Species Concentration ◽

One Dimensional ◽

Jump Distance ◽

Local Species ◽

The Individual ◽

Graph Form

A one-dimensional multicomponent kinetic model was developed to simulate the interstitial diffusion of macromolecules in a three component system, consisting of water, the macromolecule and the interstitial matrix. Movement of the individual components was modeled as occurring in finite jumps between discrete low energy wells along paths defined in terms of species occupation. The flow rate was expressed as a function of the local species concentration, the jump distance, and a kinetic frequency parameter. The model, implemented in pseudo-bond graph form, was examined by fitting it to data obtained for the transport of fluorescein tagged dextran to determine the kinetic constants for that specific system.

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A time-dependent model for high-pressure discharges in narrow ablative capillaries

Journal of Plasma Physics ◽

10.1017/s0022377800026908 ◽

1993 ◽

Vol 50 (1) ◽

pp. 51-70 ◽

Cited By ~ 19

Author(s):

D. Zoler ◽

S. Cuperman ◽

J. Ashkenazy ◽

M. Caner ◽

Z. Kaplan

Keyword(s):

High Pressure ◽

Equation Of State ◽

Time Dependent ◽

Dimensional Model ◽

Plasma Sources ◽

One Dimensional ◽

Space And Time ◽

Dependent Model ◽

Energy Equations ◽

Time Dependent Model

A time-dependent quasi-one-dimensional model is developed for studying high- pressure discharges in ablative capillaries used, for example, as plasma sources in electrothermal launchers. The main features of the model are (i) consideration of ablation effects in each of the continuity, momentum and energy equations; (ii) use of a non-ideal equation of state; and (iii) consideration of space- and time-dependent ionization.

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Discussion of “ One‐Dimensional High‐Pressure Compression of Granular Media ” by M. M. Hagerty, D. R. Hite, C. R. Ullrich, and D. J. Hagerty (January, 1993, Vol. 119, No. 1)

Journal of Geotechnical Engineering ◽

10.1061/(asce)0733-9410(1994)120:6(1102) ◽

1994 ◽

Vol 120 (6) ◽

pp. 1102-1105 ◽

Cited By ~ 1

Author(s):

I. J. Smalley ◽

C. D. F. Rogers

Keyword(s):

High Pressure ◽

Granular Media ◽

One Dimensional

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Intermolecular Interactions of Xe Atoms Confined in One-dimensional Nanochannels of Tris(o-phenylenedioxy)cyclotriphosphazene as Studied by High-pressure 129Xe NMR

Zeitschrift für Naturforschung A ◽

10.1515/zna-2003-1208 ◽

2003 ◽

Vol 58 (12) ◽

pp. 727-734 ◽

Cited By ~ 10

Author(s):

Hirokazu Kobayashi ◽

Takahiro Ueda ◽

Keisuke Miyakubo ◽

Taro Eguchi

Keyword(s):

High Pressure ◽

Nmr Spectroscopy ◽

Chemical Shift ◽

Pressure Dependence ◽

Average Distance ◽

Chemical Shift Tensor ◽

Axially Symmetric ◽

One Dimensional ◽

129Xe Nmr ◽

The One

The pressure dependence of the 129Xe chemical shift tensor confined in the Tris(o-phenylenedioxy) cyclotriphosphazene (TPP) nanochannel was investigated by high-pressure 129Xe NMR spectroscopy. The observed 129Xe spectrum in the one-dimensional TPP nanochannel (0.45 nm in diameter) exhibits a powder pattern broadened by an axially symmetric chemical shift tensor. As the pressure increases from 0.02 to 7.0 MPa, a deshielding of 90 ppm is observed for the perpendicularcomponent of the chemical shift tensor δ⊥, whereas a deshielding of about 30 ppm is observed for the parallel one, δ‖. This suggests that the components of the chemical shift tensor, δ‖ and δ⊥, are mainly dominated by the Xe-wall and Xe-Xe interaction, respectively. Furthermore, the effect of helium, which is present along with xenon gas, on the 129Xe chemical shift is examined in detail. The average distance between the Xe atoms in the nanochannel is estimated to be 0.54 nm. This was found by using δ⊥ at the saturated pressure of xenon, and comparing the increment of the chemicalshift value in δ⊥ to that of a β -phenol/Xe compound.

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Analysis of Variable Intake Runner Lengths and Intake Valve Open Timings on Engine Performances

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.663.336 ◽

2014 ◽

Vol 663 ◽

pp. 336-341 ◽

Cited By ~ 4

Author(s):

Mohd Farid Muhamad Said ◽

Zulkarnain Abdul Latiff ◽

Aminuddin Saat ◽

Mazlan Said ◽

Shaiful Fadzil Zainal Abidin

Keyword(s):

Engine Performance ◽

Intake Manifold ◽

Intake Valve ◽

Si Engine ◽

Engine Simulation ◽

Engine Model ◽

Optimum Parameters ◽

Comparison Results ◽

Variable Valve ◽

Engine Development

In this paper, engine simulation tool is used to investigate the effect of variable intake manifold and variable valve timing technologies on the engine performance at full load engine conditions. Here, an engine model of 1.6 litre four cylinders, four stroke spark ignition (SI) engine is constructed using GT-Power software to represent the real engine conditions. This constructed model is then correlated to the experimental data to make sure the accuracy of this model. The comparison results of volumetric efficiency (VE), intake manifold air pressure (MAP), exhaust manifold back pressure (BckPress) and brake specific fuel consumption (BSFC) show very well agreement with the differences of less than 4%. Then this correlated model is used to predict the engine performance at various intake runner lengths (IRL) and various intake valve open (IVO) timings. Design of experiment and optimisation tool are applied to obtain optimum parameters. Here, several configurations of IRL and IVO timing are proposed to give several options during the engine development work. A significant improvement is found at configuration of variable IVO timing and variable IRL compared to fixed IVO timing and fixed IRL.

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