Application of a New Turbulent Flame Speed Combustion Model on Burn Rate Simulation of Spark Ignition Engines

The paper presents the computational fluid dynamics (CFD) combustion modeling approach based on two combustion models. This modeling approach was applied to a hydrogen deflagration experiment conducted in a large-scale confined experimental vessel. The used combustion models were Zimont's turbulent flame-speed closure (TFC) model and Lipatnikov's flame-speed closure (FSC) model. The conducted simulations are aimed to aid identifying and evaluating the potential hydrogen risks in nuclear power plant (NPP) containment. The simulation results show good agreement with experiment for axial flame propagation using the Lipatnikov combustion model. However, substantial overprediction in radial flame propagation is observed using both combustion models, which consequently results also in overprediction of the pressure increase rate and overall combustion energy output. As assumed for a large-scale experiment without any turbulence inducing structures, the combustion took place in low-turbulence regimes, where the Lipatnikov combustion model, due to its inclusion of quasi-laminar source term, has advantage over the Zimont model.

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Large-Scale Homogeneous Hydrogen-Air-Steam Deflagration Experiment Simulated Using Two Turbulent Flame Speed Closure Models

Volume 5: Student Paper Competition ◽

10.1115/icone24-60134 ◽

2016 ◽

Author(s):

Tadej Holler ◽

Varun Jain ◽

Ed M. J. Komen ◽

Ivo Kljenak

Keyword(s):

Flame Propagation ◽

Nuclear Power ◽

Large Scale ◽

Turbulent Flame ◽

Turbulent Flames ◽

Flame Speed ◽

Energy Output ◽

Combustion Model ◽

Turbulent Flame Speed ◽

Combustion Models

The CFD combustion modeling approach based on two combustion models was applied to a hydrogen deflagration experiment conducted in a large-scale confined experimental vessel. The used combustion models were Zimont’s Turbulent Flames Speed Closure (TFC) model and Lipatnikov’s Flame Speed Closure (FSC) model. The conducted simulations are aimed to aid identifying and evaluating the potential hydrogen risks in Nuclear Power Plant (NPP) containment. The simulation results show good agreement with experiment for axial flame propagation using the Lipatnikov combustion model. However substantial overprediction in radial flame propagation is observed using both combustion models, which consequently results also in overprediction of the pressure increase rate and overall combustion energy output. As assumed for a large-scale experiment without any turbulence inducing structures, the combustion took place in low-turbulence regimes, where the Lipatnikov combustion model, due to its inclusion of quasi-laminar source term, has advantage over the Zimont model.

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Spark Ignition Simulations and the Generation of Ignition Maps by Means of a Turbulent Flame Speed Closure Approach

Volume 2: Combustion, Fuels and Emissions, Parts A and B ◽

10.1115/gt2010-22211 ◽

2010 ◽

Cited By ~ 2

Author(s):

Jan M. Boyde ◽

Massimiliano Di Domenico ◽

Berthold Noll ◽

Manfred Aigner

Keyword(s):

Turbulent Flame ◽

Spark Ignition ◽

Flame Speed ◽

Test Case ◽

Ignition Energy ◽

Mean Flow ◽

Flame Kernel ◽

Turbulent Flame Speed ◽

Flow Parameters ◽

Partially Premixed

This paper presents a numerical investigation of ignition phenomena in turbulent partially premixed methane/air flames. In this work, a turbulent flame speed closure model (TFC) is employed with an ignition delay module extension. The model is applied to two partially premixed test cases under standard conditions in the configuration of a shearless flame and a counter flow flame, respectively. For both setups, the flame kernel propagation and consequent establishment or extinction of the flame are examined. A shearless configuration represents the first test case under investigation. The study demonstrates the large influence of the mean flow parameters on achieving a successful ignition of the domain. The second test case under examination is a counterflow geometry. A sensitivity analysis with respect to spark ignition position and ignition energy is performed. The simulations show that flame kernel spreading is largely influenced by the magnitude of turbulence occurring in the flow, leading to an enhanced propagation in areas with a moderate turbulence degree, whereas high turbulence can be detrimental for the flame establishment due to extensive heat losses. Another observation is that a successful ignition of the domain can occur, even in cases in which the ignition energy is not placed in an area with flammable mixture. The comparison with experimental data shows a good agreement, both in terms of successful ignition and flame kernel propagation.

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Three-dimensional computational fluid dynamics simulation of hydrogen engines using a turbulent flame speed closure combustion model

International Journal of Engine Research ◽

10.1177/1468087412438796 ◽

2012 ◽

Vol 13 (5) ◽

pp. 464-481 ◽

Cited By ~ 4

Author(s):

Udo Gerke ◽

Konstantinos Boulouchos

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Laminar Flame ◽

Turbulent Flame ◽

Three Dimensional ◽

Flame Speed ◽

Combustion Model ◽

Laminar Flame Speed ◽

Release Rates ◽

Turbulent Flame Speed

The mixture formation and combustion process of a hydrogen direct-injection internal combustion engine is computed using a modified version of a commercial three-dimensional computational fluid dynamics code. The aim of the work is the evaluation of hydrogen laminar flame speed correlations and turbulent flame speed closures with respect to combustion of premixed and stratified mixtures at various levels of air-to-fuel equivalence ratio. Heat-release rates derived from in-cylinder pressure traces are used for the validation of the combustion simulations. A turbulent combustion model with closures for a turbulent flame speed is investigated. The value of the computed heat-release rates mainly depends on the quality of laminar burning velocities and standard of turbulence quantities provided to the combustion model. Combustion simulations performed with experimentally derived laminar flame speed data give better results than those using laminar flame speeds obtained from a kinetic scheme. However, experimental data of hydrogen laminar flame speeds found in the literature are limited regarding the range of pressures, temperatures and air-to-fuel equivalence ratios, and do not comply with the demand of high-pressure engine-relevant conditions.

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A Data-Driven Methodology for the Simulation of Turbulent Flame Speed across Engine-Relevant Combustion Regimes

Energies ◽

10.3390/en14144210 ◽

2021 ◽

Vol 14 (14) ◽

pp. 4210

Author(s):

Alessandro d’Adamo ◽

Clara Iacovano ◽

Stefano Fontanesi

Keyword(s):

Turbulent Combustion ◽

Internal Combustion Engines ◽

Turbulent Flame ◽

Flame Speed ◽

Data Driven ◽

Combustion Model ◽

Virtual Design ◽

Turbulent Flame Speed ◽

Combustion Models ◽

Combustion Regimes

Turbulent combustion modelling in internal combustion engines (ICEs) is a challenging task. It is commonly synthetized by incorporating the interaction between chemical reactions and turbulent eddies into a unique term, namely turbulent flame speed sT. The task is very complex considering the variety of turbulent and chemical scales resulting from engine load/speed variations. In this scenario, advanced turbulent combustion models are asked to predict accurate burn rates under a wide range of turbulence–flame interaction regimes. The framework is further complicated by the difficulty in unambiguously evaluating in-cylinder turbulence and by the poor coherence of turbulent flame speed (sT) measurements in the literature. Finally, the simulated sT from combustion models is found to be rarely assessed in a rigorous manner. A methodology is presented to objectively measure the simulated sT by a generic combustion model over a range of engine-relevant combustion regimes, from Da = 0.5 to Da = 75 (i.e., from the thin reaction regime to wrinkled flamelets). A test case is proposed to assess steady-state burn rates under specified turbulence in a RANS modelling framework. The methodology is applied to a widely adopted combustion model (ECFM-3Z) and the comparison of the simulated sT with experimental datasets allows to identify modelling improvement areas. Dynamic functions are proposed based on turbulence intensity and Damköhler number. Finally, simulations using the improved flame speed are carried out and a satisfactory agreement of the simulation results with the experimental/theoretical correlations is found. This confirms the effectiveness and the general applicability of the methodology to any model. The use of grid/time resolution typical of ICE combustion simulations strengthens the relevance of the proposed dynamic functions. The presented analysis allows to improve the adherence of the simulated burn rate to that of literature turbulent flames, and it unfolds the innovative possibility to objectively test combustion models under any prescribed turbulence/flame interaction regime. The solid data-driven representation of turbulent combustion physics is expected to reduce the tuning effort in ICE combustion simulations, providing modelling robustness in a very critical area for virtual design of innovative combustion systems.

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A MEAN VALUE MODEL FOR ESTIMATION OF LAMINAR AND TURBULENT FLAME SPEED IN SPARK-IGNITION ENGINE

International Journal of Automotive and Mechanical Engineering ◽

10.15282/ijame.11.2015.5.0186 ◽

2015 ◽

Vol 11 ◽

pp. 2224-2234 ◽

Cited By ~ 3

Author(s):

Ali Ghanaati ◽

◽

Intan Z. Mat Darus ◽

Mohd Farid Muhamad Said ◽

Amin Mahmoudzadeh Andwari ◽

...

Keyword(s):

Turbulent Flame ◽

Spark Ignition ◽

Mean Value ◽

Flame Speed ◽

Spark Ignition Engine ◽

Turbulent Flame Speed ◽

Mean Value Model ◽

Value Model

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Prediction of Ultra-Lean SI Engine Performance by QD-Combustion Model With an Improved Laminar Flame Speed

ASME 2020 Power Conference ◽

10.1115/power2020-16061 ◽

2020 ◽

Author(s):

Ratnak Sok ◽

Jin Kusaka ◽

Kyohei Yamaguchi

Keyword(s):

Gasoline Engine ◽

Laminar Flame ◽

Burning Velocity ◽

Turbulent Flame ◽

Combustion Process ◽

Combustion Characteristics ◽

Flame Speed ◽

Combustion Model ◽

Lean Mixture ◽

Turbulent Flame Speed

Abstract A quasi-dimensional (QD) simulation model is a preferred method to predict combustion in the gasoline engines with reliable results and shorter calculation time compared with multi-dimensional simulation. The combustion phenomena in spark ignition (SI) engines are highly turbulent, and at initial stage of the combustion process, turbulent flame speed highly depends on laminar burning velocity SL. A major parameter of the QD combustion model is an accurate prediction of the SL, which is unstable under low engine speed and ultra-lean mixture. This work investigates the applicability of the combustion model for evaluating the combustion characteristics of a high-tumble port gasoline engine operated under ultra-lean mixture (equivalence ratio up to ϕ = 0.5) which is out of the range of currently available SL functions initially developed for a single component fuel. In this study, the SL correlation is improved for a gasoline surrogate fuel (5 components). Predicted SL data from the conventional and improved functions are compared with experimental SL data taken from a constant-volume chamber under micro-gravity condition. The SL measurements are done at reference conditions at temperature of 300K, pressure of 0.1MPaa, and at elevated conditions whose temperature = 360K, pressure = 0.1, 0.3, and 0.5 MPaa. Results show that the conventional SL model over-predicts flame speeds under all conditions. Moreover, the model predicts negative SL at very lean (ϕ ≤ 0.3) and rich (ϕ ≥ 1.9) mixture while the revised SL is well validated with the measured data. The improved SL formula is then incorporated into the QD combustion model by a user-defined function in GT-Power simulation. The engine experimental data are taken at 1000 RPM and 2000 RPM under engine load IMEPn = 0.4–0.8 MPa (with 0.1 increment) and ϕ ranges are up to 0.5. The results shows that the simulated engine performances and combustion characteristics are well validated with the experiments within 6% accuracy by using the QD combustion model coupled with the improved SL. A sensitivity analysis of the model is also in good agreement with the experiments under cyclic variation (averaged cycle, high IMEP or stable cycle, and low IMEP or unstable cycle).

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Transient Combustion Modeling of an Oscillating Lean Premixed Methane/Air Flame

Volume 3: Combustion, Fuels and Emissions, Parts A and B ◽

10.1115/gt2008-51125 ◽

2008 ◽

Author(s):

Jan A. M. Withag ◽

Jim B. W. Kok ◽

Khawar Syed

Keyword(s):

Laminar Flame ◽

Turbulent Flame ◽

Low Frequency ◽

Turbulence Models ◽

Flame Speed ◽

Combustion Model ◽

Lean Premixed Combustion ◽

Combustion Modeling ◽

Turbulent Flame Speed ◽

Lean Premixed

The main objective of the present study is to demonstrate accurate low frequency transient turbulent combustion modeling. For accurate flame dynamics some improvements were made to the standard TFC combustion model for lean premixed combustion. With use of a 1D laminar flamelet code, predictions have been made for the laminar flame speed and the critical strain rate to improve the TFC (Turbulent Flame Speed Closure) combustion model. The computational fluid dynamics program CFX is used to perform transient simulations. These results were compared with experimental data of Weigand et al [1]. Two different turbulence models have been used for predictions of the turbulent flow.

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