Fluctuations in the energetic properties of a spark-ignition engine model with variability

Lev Guzmán-Vargas, Pedro L. Curto-Risso, Alejandro Medina, Antonio Calvo-Hernández, Fernando Angulo-Brown

Research output: Contribution to journalArticle

8 Citations (Scopus)

Abstract

We study the energetic functions obtained in a simulated spark-ignited engine that incorporates cyclic variability through a quasi-dimensional combustion model. Our analyses are focused on the effects of the fuel-air equivalence ratio of the mixture simultaneously over the cycle-to-cycle fluctuations of heat release (QR) and the performance outputs, such as the power (P) and the efficiency (η). We explore the fluctuant behavior for QR, P and η related to random variations of the basic physical parameters in an entrainment or eddy-burning combustion model. P and η show triangle shaped first return maps, while QR exhibits a structured map, especially at intermediated fuel-air ratios. Structure disappears to a considerable extent in the case of heat release and close-to-stoichiometry fuel-air ratios. By analyzing the fractal dimension to explore the presence of correlations at different scales, we find that whereas QR displays short-range correlations for intermediate values of the fuel ratio, both P and η are characterized by a single scaling exponent, denoting irregular fluctuations. A novel noisy loop-shaped P vs. η plot for a large number of engine cyclesis obtained. This plot, which evidences different levels of irreversibilities as the fuel ratio changes, becomes the observed loop P vs. η curve when fluctuations are disregarded, and thus, only the mean values for efficiency and power are considered. © 2013 by the authors.
Original languageAmerican English
Pages (from-to)3277-3296
Number of pages20
JournalEntropy
DOIs
StatePublished - 1 Jan 2013

Fingerprint

spark ignition
engines
fuel-air ratio
plots
heat
cycles
entrainment
sparks
triangles
equivalence
stoichiometry
fractals
exponents
vortices
scaling
output
air
curves

Cite this

Guzmán-Vargas, Lev ; Curto-Risso, Pedro L. ; Medina, Alejandro ; Calvo-Hernández, Antonio ; Angulo-Brown, Fernando. / Fluctuations in the energetic properties of a spark-ignition engine model with variability. In: Entropy. 2013 ; pp. 3277-3296.
@article{f5f192476ccd4f90bff54f6d570037d6,
title = "Fluctuations in the energetic properties of a spark-ignition engine model with variability",
abstract = "We study the energetic functions obtained in a simulated spark-ignited engine that incorporates cyclic variability through a quasi-dimensional combustion model. Our analyses are focused on the effects of the fuel-air equivalence ratio of the mixture simultaneously over the cycle-to-cycle fluctuations of heat release (QR) and the performance outputs, such as the power (P) and the efficiency (η). We explore the fluctuant behavior for QR, P and η related to random variations of the basic physical parameters in an entrainment or eddy-burning combustion model. P and η show triangle shaped first return maps, while QR exhibits a structured map, especially at intermediated fuel-air ratios. Structure disappears to a considerable extent in the case of heat release and close-to-stoichiometry fuel-air ratios. By analyzing the fractal dimension to explore the presence of correlations at different scales, we find that whereas QR displays short-range correlations for intermediate values of the fuel ratio, both P and η are characterized by a single scaling exponent, denoting irregular fluctuations. A novel noisy loop-shaped P vs. η plot for a large number of engine cyclesis obtained. This plot, which evidences different levels of irreversibilities as the fuel ratio changes, becomes the observed loop P vs. η curve when fluctuations are disregarded, and thus, only the mean values for efficiency and power are considered. {\circledC} 2013 by the authors.",
author = "Lev Guzm{\'a}n-Vargas and Curto-Risso, {Pedro L.} and Alejandro Medina and Antonio Calvo-Hern{\'a}ndez and Fernando Angulo-Brown",
year = "2013",
month = "1",
day = "1",
doi = "10.3390/e15083367",
language = "American English",
pages = "3277--3296",
journal = "Entropy",
issn = "1099-4300",
publisher = "Multidisciplinary Digital Publishing Institute (MDPI)",

}

Fluctuations in the energetic properties of a spark-ignition engine model with variability. / Guzmán-Vargas, Lev; Curto-Risso, Pedro L.; Medina, Alejandro; Calvo-Hernández, Antonio; Angulo-Brown, Fernando.

In: Entropy, 01.01.2013, p. 3277-3296.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Fluctuations in the energetic properties of a spark-ignition engine model with variability

AU - Guzmán-Vargas, Lev

AU - Curto-Risso, Pedro L.

AU - Medina, Alejandro

AU - Calvo-Hernández, Antonio

AU - Angulo-Brown, Fernando

PY - 2013/1/1

Y1 - 2013/1/1

N2 - We study the energetic functions obtained in a simulated spark-ignited engine that incorporates cyclic variability through a quasi-dimensional combustion model. Our analyses are focused on the effects of the fuel-air equivalence ratio of the mixture simultaneously over the cycle-to-cycle fluctuations of heat release (QR) and the performance outputs, such as the power (P) and the efficiency (η). We explore the fluctuant behavior for QR, P and η related to random variations of the basic physical parameters in an entrainment or eddy-burning combustion model. P and η show triangle shaped first return maps, while QR exhibits a structured map, especially at intermediated fuel-air ratios. Structure disappears to a considerable extent in the case of heat release and close-to-stoichiometry fuel-air ratios. By analyzing the fractal dimension to explore the presence of correlations at different scales, we find that whereas QR displays short-range correlations for intermediate values of the fuel ratio, both P and η are characterized by a single scaling exponent, denoting irregular fluctuations. A novel noisy loop-shaped P vs. η plot for a large number of engine cyclesis obtained. This plot, which evidences different levels of irreversibilities as the fuel ratio changes, becomes the observed loop P vs. η curve when fluctuations are disregarded, and thus, only the mean values for efficiency and power are considered. © 2013 by the authors.

AB - We study the energetic functions obtained in a simulated spark-ignited engine that incorporates cyclic variability through a quasi-dimensional combustion model. Our analyses are focused on the effects of the fuel-air equivalence ratio of the mixture simultaneously over the cycle-to-cycle fluctuations of heat release (QR) and the performance outputs, such as the power (P) and the efficiency (η). We explore the fluctuant behavior for QR, P and η related to random variations of the basic physical parameters in an entrainment or eddy-burning combustion model. P and η show triangle shaped first return maps, while QR exhibits a structured map, especially at intermediated fuel-air ratios. Structure disappears to a considerable extent in the case of heat release and close-to-stoichiometry fuel-air ratios. By analyzing the fractal dimension to explore the presence of correlations at different scales, we find that whereas QR displays short-range correlations for intermediate values of the fuel ratio, both P and η are characterized by a single scaling exponent, denoting irregular fluctuations. A novel noisy loop-shaped P vs. η plot for a large number of engine cyclesis obtained. This plot, which evidences different levels of irreversibilities as the fuel ratio changes, becomes the observed loop P vs. η curve when fluctuations are disregarded, and thus, only the mean values for efficiency and power are considered. © 2013 by the authors.

U2 - 10.3390/e15083367

DO - 10.3390/e15083367

M3 - Article

SP - 3277

EP - 3296

JO - Entropy

JF - Entropy

SN - 1099-4300

ER -