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Michael J Pilling - One of the best experts on this subject based on the ideXlab platform.
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Semantically enhanced provenance capture for chamber model development with a master Chemical Mechanism.
Philosophical transactions. Series A Mathematical physical and engineering sciences, 2008Co-Authors: C. J. Martin, Michael J Pilling, M.h. Haji, P.m. Dew, P.k. JimackAbstract:The development and maintenance of benchmark databases within scientific communities is reliant on interactions with database users. We explore the role of semantically enhanced provenance for computational modelling processes that make use of one such database: the master Chemical Mechanism, a key resource within the atmospheric chemistry community.
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protocol for the development of the master Chemical Mechanism mcm v3 part a tropospheric degradation of non aromatic volatile organic compounds
Atmospheric Chemistry and Physics, 2002Co-Authors: M. E. Jenkin, R.g. Derwent, S. M. Saunders, Michael J PillingAbstract:Kinetic and mechanistic data relevant to the tropospheric degradation of aromatic volatile organic compounds (VOC) have been used to define a Mechanism development protocol, which has been used to construct degradation schemes for 18 aromatic VOC as part of version 3 of the Master Chemical Mechanism (MCM v3). This is complementary to the treatment of 107 non-aromatic VOC, presented in a companion paper. The protocol is divided into a series of subsections describing initiation reactions, the degradation chemistry to first generation products via a number of competitive routes, and the further degradation of first and subsequent generation products. Emphasis is placed on describing where the treatment differs from that applied to the non-aromatic VOC. The protocol is based on work available in the open literature up to the beginning of 2001, and some other studies known by the authors which were under review at the time. PhotoChemical Ozone Creation Potentials (POCP) have been calculated for the 18 aromatic VOC in MCM v3 for idealised conditions appropriate to north-west Europe, using a photoChemical trajectory model. The POCP values provide a measure of the relative ozone forming abilities of the VOC. These show distinct differences from POCP values calculated previously for the aromatics, using earlier versions of the MCM, and reasons for these differences are discussed.
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development and testing of a comprehensive Chemical Mechanism for the oxidation of methane
International Journal of Chemical Kinetics, 2001Co-Authors: Kevin J Hughes, Tamas Turanyi, A R Clague, Michael J PillingAbstract:A comprehensive Chemical Mechanism to describe the oxidation of methane has been developed, consisting of 351 irreversible reactions of 37 species. The Mechanism also accounts for the oxidation kinetics of hydrogen, carbon monoxide, ethane, and ethene in flames and homogeneous ignition systems in a wide concentration range. It has been tested against a variety of experimental measurements of laminar flame velocities, laminar flame species profiles, and ignition delay times. The highest sensitivity reactions of the Mechanism are discussed in detail and compared with the same reactions in the GRI, Chevalier, and Konnov Mechanisms. Similarities and differences of the four Mechanisms are discussed. The Mechanism is available on the Internet as a fully documented CHEMKIN data file at the address http://www.chem.leeds.ac.uk/Combustion/Combustion.html. © 2001 John Wiley & Sons, Inc. Int J Chem Kinet 33: 513–538, 2001
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Characterization of the Reactivities of Volatile Organic Compounds Using a Master Chemical Mechanism
Journal of the Air & Waste Management Association (1995), 2001Co-Authors: Richard G. Derwent, Michael E. Jenkin, Sandra M. Saunders, Michael J PillingAbstract:ABSTRACT A comprehensive description of the ozone-forming potentials of 101 organic compounds has been constructed under North American urban "averaged conditions" using a detailed master Chemical Mechanism and a simple air parcel trajectory model. This Chemical Mechanism describes the reactions of 3603 Chemical species taking part in more than 10,500 Chemical reactions. An index value has been calculated for each organic compound, which describes the increment in ozone concentrations found downwind of an urban area following the emission of a fixed increment in the mass emission of each organic compound. These indices, termed photoChemical ozone creation potentials (POCPs), have been expressed on a scale relative to ethylene (ethene) = 100, and a reactivity scale has been generated for alkanes, alkenes, and oxygenated and halogenated organic compounds. A high degree of correlation (R2 = 0.9) was found between these POCP values and the most widely accepted urban reactivity scale. While the reactivities of...
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photoChemical ozone creation potentials for organic compounds in northwest europe calculated with a master Chemical Mechanism
Atmospheric Environment, 1998Co-Authors: R.g. Derwent, Sandra M. Saunders, M. E. Jenkin, Michael J PillingAbstract:Abstract Master Chemical Mechanism containing over 2400 Chemical species and over 7100 Chemical reactions is employed here to describe the atmospheric degradation of 120 organic compounds and the associated regional scale ozone and PAN formation under conditions appropriate to the polluted boundary layer over northwest Europe. PhotoChemical ozone and PAN creation potentials (POCP and PPCP) are derived for each organic compound from their propensities to form ozone and PAN relative to ethylene and propylene, respectively. The robustness of these POCP values to changes in the NOx emission densities across Europe is tested and the values are compared with previous studies. The POCP values are reviewed and rationalised against the background of our current understanding of the intrinsic properties of each organic compound, their atmospheric degradation pathways and other mechanistic data. These POCPs should assist policy-makers in defining realistic and robust pollution control strategies which focus on those organic compounds which contribute most to regional scale ozone formation across northwest Europe.
M. E. Jenkin - One of the best experts on this subject based on the ideXlab platform.
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Development of a detailed Chemical Mechanism (MCMv3.1) for the atmospheric oxidation of aromatic hydrocarbons
Atmospheric Chemistry and Physics Discussions, 2004Co-Authors: C. Bloss, V. Wagner, M. E. Jenkin, R. Volkamer, W. J. Bloss, J. D. Lee, D. E. Heard, K. Wirtz, M. Martin-reviejo, G. ReaAbstract:The Master Chemical Mechanism has been updated from MCMv3 to MCMv3.1 in order to take into account recent improvements in the understanding of aromatic photo-oxidation. Newly available kinetic and product data from the literature has been incorporated into the Mechanism. In particular, the degradation Mechanisms for hydroxyarenes have been revised following the observation of high yields of ring-retained products, and product studies of aromatic oxidation under relatively low NOx conditions have provided new information on the branching ratios to first generation products. Experiments have been carried out at the European Photoreactor (EUPHORE) to investigate key subsets of the toluene system. These results have been used to test our understanding of toluene oxidation, and where possible, refine the degradation Mechanisms. The evaluation of MCMv3 and MCMv3.1 using data on benzene, toluene, p-xylene and 1,3,5-trimethylbenzene photosmog systems is described in a companion paper, and significant model shortcomings are identified. Ideas for additional modifications to the Mechanisms, and for future experiments to further our knowledge of the details of aromatic photo-oxidation are discussed.
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development of a detailed Chemical Mechanism mcmv3 1 for the atmospheric oxidation of aromatic hydrocarbons
Atmospheric Chemistry and Physics, 2004Co-Authors: C. Bloss, V. Wagner, M. E. Jenkin, R. Volkamer, W. J. Bloss, D. E. Heard, K. Wirtz, Montserrat Martinreviejo, John C WengerAbstract:Abstract. The Master Chemical Mechanism has been updated from MCMv3 to MCMv3.1 in order to take into account recent improvements in the understanding of aromatic photo-oxidation. Newly available kinetic and product data from the literature have been incorporated into the Mechanism. In particular, the degradation Mechanisms for hydroxyarenes have been revised following the observation of high yields of ring-retained products, and product studies of aromatic oxidation under relatively low NOx conditions have provided new information on the branching ratios to first generation products. Experiments have been carried out at the European Photoreactor (EUPHORE) to investigate key subsets of the toluene system. These results have been used to test our understanding of toluene oxidation, and, where possible, refine the degradation Mechanisms. The evaluation of MCMv3 and MCMv3.1 using data on benzene, toluene, p-xylene and 1,3,5-trimethylbenzene photosmog systems is described in a companion paper, and significant model shortcomings are identified. Ideas for additional modifications to the Mechanisms, and for future experiments to further our knowledge of the details of aromatic photo-oxidation are discussed.
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Protocol for the development of the Master Chemical Mechanism, MCM v3 (Part A): tropospheric degradation of non-aromatic volatile organic compounds
Atmospheric Chemistry and Physics, 2003Co-Authors: S. M. Saunders, M. E. Jenkin, R.g. Derwent, M. J. PillingAbstract:Kinetic and mechanistic data relevant to the tropospheric degradation of volatile organic compounds (VOC), and the production of secondary pollutants, have previously been used to define a protocol which underpinned the construction of a near-explicit Master Chemical Mechanism. In this paper, an update to the previous protocol is presented, which has been used to define degradation schemes for 107 non-aromatic VOC as part of version 3 of the Master Chemical Mechanism (MCM v3). The treatment of 18 aromatic VOC is described in a companion paper. The protocol is divided into a series of subsections describing initiation reactions, the reactions of the radical intermediates and the further degradation of first and subsequent generation products. Emphasis is placed on updating the previous information, and outlining the methodology which is specifically applicable to VOC not considered previously (e.g. a- and b-pinene). The present protocol aims to take into consideration work available in the open literature up to the beginning of 2001, and some other studies known by the authors which were under review at the time. Application of MCM v3 in appropriate box models indicates that the representation of isoprene degradation provides a good description of the speciated distribution of oxygenated organic products observed in reported field studies where isoprene was the dominant emitted hydrocarbon, and that the a-pinene degradation chemistry provides a good description of the time dependence of key gas phase species in a-pinene/NOX photo-oxidation experiments carried out in the European Photoreactor (EUPHORE). PhotoChemical Ozone Creation Potentials (POCP) have been calculated for the 106 non-aromatic non-methane VOC in MCM v3 for idealised conditions appropriate to north-west Europe, using a photoChemical trajectory model. The POCP values provide a measure of the relative ozone forming abilities of the VOC. Where applicable, the values are compared with those calculated with previous versions of the MCM.
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Protocol for the development of the Master Chemical Mechanism, MCM v3 (Part B): tropospheric degradation of aromatic volatile organic compounds
Atmospheric Chemistry and Physics, 2003Co-Authors: M. E. Jenkin, V. Wagner, S. M. Saunders, M. J. PillingAbstract:Kinetic and mechanistic data relevant to the tropospheric degradation of aromatic volatile organic compounds (VOC) have been used to define a Mechanism development protocol, which has been used to construct degradation schemes for 18 aromatic VOC as part of version 3 of the Master Chemical Mechanism (MCM v3). This is complementary to the treatment of 107 non-aromatic VOC, presented in a companion paper. The protocol is divided into a series of subsections describing initiation reactions, the degradation chemistry to first generation products via a number of competitive routes, and the further degradation of first and subsequent generation products. Emphasis is placed on describing where the treatment differs from that applied to the non-aromatic VOC. The protocol is based on work available in the open literature up to the beginning of 2001, and some other studies known by the authors which were under review at the time. PhotoChemical Ozone Creation Potentials (POCP) have been calculated for the 18 aromatic VOC in MCM v3 for idealised conditions appropriate to north-west Europe, using a photoChemical trajectory model. The POCP values provide a measure of the relative ozone forming abilities of the VOC. These show distinct differences from POCP values calculated previously for the aromatics, using earlier versions of the MCM, and reasons for these differences are discussed.
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protocol for the development of the master Chemical Mechanism mcm v3 part a tropospheric degradation of non aromatic volatile organic compounds
Atmospheric Chemistry and Physics, 2002Co-Authors: M. E. Jenkin, R.g. Derwent, S. M. Saunders, Michael J PillingAbstract:Kinetic and mechanistic data relevant to the tropospheric degradation of aromatic volatile organic compounds (VOC) have been used to define a Mechanism development protocol, which has been used to construct degradation schemes for 18 aromatic VOC as part of version 3 of the Master Chemical Mechanism (MCM v3). This is complementary to the treatment of 107 non-aromatic VOC, presented in a companion paper. The protocol is divided into a series of subsections describing initiation reactions, the degradation chemistry to first generation products via a number of competitive routes, and the further degradation of first and subsequent generation products. Emphasis is placed on describing where the treatment differs from that applied to the non-aromatic VOC. The protocol is based on work available in the open literature up to the beginning of 2001, and some other studies known by the authors which were under review at the time. PhotoChemical Ozone Creation Potentials (POCP) have been calculated for the 18 aromatic VOC in MCM v3 for idealised conditions appropriate to north-west Europe, using a photoChemical trajectory model. The POCP values provide a measure of the relative ozone forming abilities of the VOC. These show distinct differences from POCP values calculated previously for the aromatics, using earlier versions of the MCM, and reasons for these differences are discussed.
S. M. Saunders - One of the best experts on this subject based on the ideXlab platform.
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Protocol for the development of the Master Chemical Mechanism, MCM v3 (Part A): tropospheric degradation of non-aromatic volatile organic compounds
Atmospheric Chemistry and Physics, 2003Co-Authors: S. M. Saunders, M. E. Jenkin, R.g. Derwent, M. J. PillingAbstract:Kinetic and mechanistic data relevant to the tropospheric degradation of volatile organic compounds (VOC), and the production of secondary pollutants, have previously been used to define a protocol which underpinned the construction of a near-explicit Master Chemical Mechanism. In this paper, an update to the previous protocol is presented, which has been used to define degradation schemes for 107 non-aromatic VOC as part of version 3 of the Master Chemical Mechanism (MCM v3). The treatment of 18 aromatic VOC is described in a companion paper. The protocol is divided into a series of subsections describing initiation reactions, the reactions of the radical intermediates and the further degradation of first and subsequent generation products. Emphasis is placed on updating the previous information, and outlining the methodology which is specifically applicable to VOC not considered previously (e.g. a- and b-pinene). The present protocol aims to take into consideration work available in the open literature up to the beginning of 2001, and some other studies known by the authors which were under review at the time. Application of MCM v3 in appropriate box models indicates that the representation of isoprene degradation provides a good description of the speciated distribution of oxygenated organic products observed in reported field studies where isoprene was the dominant emitted hydrocarbon, and that the a-pinene degradation chemistry provides a good description of the time dependence of key gas phase species in a-pinene/NOX photo-oxidation experiments carried out in the European Photoreactor (EUPHORE). PhotoChemical Ozone Creation Potentials (POCP) have been calculated for the 106 non-aromatic non-methane VOC in MCM v3 for idealised conditions appropriate to north-west Europe, using a photoChemical trajectory model. The POCP values provide a measure of the relative ozone forming abilities of the VOC. Where applicable, the values are compared with those calculated with previous versions of the MCM.
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Protocol for the development of the Master Chemical Mechanism, MCM v3 (Part B): tropospheric degradation of aromatic volatile organic compounds
Atmospheric Chemistry and Physics, 2003Co-Authors: M. E. Jenkin, V. Wagner, S. M. Saunders, M. J. PillingAbstract:Kinetic and mechanistic data relevant to the tropospheric degradation of aromatic volatile organic compounds (VOC) have been used to define a Mechanism development protocol, which has been used to construct degradation schemes for 18 aromatic VOC as part of version 3 of the Master Chemical Mechanism (MCM v3). This is complementary to the treatment of 107 non-aromatic VOC, presented in a companion paper. The protocol is divided into a series of subsections describing initiation reactions, the degradation chemistry to first generation products via a number of competitive routes, and the further degradation of first and subsequent generation products. Emphasis is placed on describing where the treatment differs from that applied to the non-aromatic VOC. The protocol is based on work available in the open literature up to the beginning of 2001, and some other studies known by the authors which were under review at the time. PhotoChemical Ozone Creation Potentials (POCP) have been calculated for the 18 aromatic VOC in MCM v3 for idealised conditions appropriate to north-west Europe, using a photoChemical trajectory model. The POCP values provide a measure of the relative ozone forming abilities of the VOC. These show distinct differences from POCP values calculated previously for the aromatics, using earlier versions of the MCM, and reasons for these differences are discussed.
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protocol for the development of the master Chemical Mechanism mcm v3 part a tropospheric degradation of non aromatic volatile organic compounds
Atmospheric Chemistry and Physics, 2002Co-Authors: M. E. Jenkin, R.g. Derwent, S. M. Saunders, Michael J PillingAbstract:Kinetic and mechanistic data relevant to the tropospheric degradation of aromatic volatile organic compounds (VOC) have been used to define a Mechanism development protocol, which has been used to construct degradation schemes for 18 aromatic VOC as part of version 3 of the Master Chemical Mechanism (MCM v3). This is complementary to the treatment of 107 non-aromatic VOC, presented in a companion paper. The protocol is divided into a series of subsections describing initiation reactions, the degradation chemistry to first generation products via a number of competitive routes, and the further degradation of first and subsequent generation products. Emphasis is placed on describing where the treatment differs from that applied to the non-aromatic VOC. The protocol is based on work available in the open literature up to the beginning of 2001, and some other studies known by the authors which were under review at the time. PhotoChemical Ozone Creation Potentials (POCP) have been calculated for the 18 aromatic VOC in MCM v3 for idealised conditions appropriate to north-west Europe, using a photoChemical trajectory model. The POCP values provide a measure of the relative ozone forming abilities of the VOC. These show distinct differences from POCP values calculated previously for the aromatics, using earlier versions of the MCM, and reasons for these differences are discussed.
M. J. Pilling - One of the best experts on this subject based on the ideXlab platform.
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Semantically enhanced provenance capturefor chamber model development witha master Chemical Mechanism
2009Co-Authors: C. J. Martin, M.h. Haji, P.m. Dew, M. J. Pilling, P.k. JimackAbstract:The development and maintenance of benchmark databases within scientific communities is reliant on interactions with database users.We explore the role of semantically enhanced provenance for computational modelling processes that make use of one such database: the master Chemical Mechanism, a key resource within the atmospheric chemistry community.
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Protocol for the development of the Master Chemical Mechanism, MCM v3 (Part A): tropospheric degradation of non-aromatic volatile organic compounds
Atmospheric Chemistry and Physics, 2003Co-Authors: S. M. Saunders, M. E. Jenkin, R.g. Derwent, M. J. PillingAbstract:Kinetic and mechanistic data relevant to the tropospheric degradation of volatile organic compounds (VOC), and the production of secondary pollutants, have previously been used to define a protocol which underpinned the construction of a near-explicit Master Chemical Mechanism. In this paper, an update to the previous protocol is presented, which has been used to define degradation schemes for 107 non-aromatic VOC as part of version 3 of the Master Chemical Mechanism (MCM v3). The treatment of 18 aromatic VOC is described in a companion paper. The protocol is divided into a series of subsections describing initiation reactions, the reactions of the radical intermediates and the further degradation of first and subsequent generation products. Emphasis is placed on updating the previous information, and outlining the methodology which is specifically applicable to VOC not considered previously (e.g. a- and b-pinene). The present protocol aims to take into consideration work available in the open literature up to the beginning of 2001, and some other studies known by the authors which were under review at the time. Application of MCM v3 in appropriate box models indicates that the representation of isoprene degradation provides a good description of the speciated distribution of oxygenated organic products observed in reported field studies where isoprene was the dominant emitted hydrocarbon, and that the a-pinene degradation chemistry provides a good description of the time dependence of key gas phase species in a-pinene/NOX photo-oxidation experiments carried out in the European Photoreactor (EUPHORE). PhotoChemical Ozone Creation Potentials (POCP) have been calculated for the 106 non-aromatic non-methane VOC in MCM v3 for idealised conditions appropriate to north-west Europe, using a photoChemical trajectory model. The POCP values provide a measure of the relative ozone forming abilities of the VOC. Where applicable, the values are compared with those calculated with previous versions of the MCM.
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Protocol for the development of the Master Chemical Mechanism, MCM v3 (Part B): tropospheric degradation of aromatic volatile organic compounds
Atmospheric Chemistry and Physics, 2003Co-Authors: M. E. Jenkin, V. Wagner, S. M. Saunders, M. J. PillingAbstract:Kinetic and mechanistic data relevant to the tropospheric degradation of aromatic volatile organic compounds (VOC) have been used to define a Mechanism development protocol, which has been used to construct degradation schemes for 18 aromatic VOC as part of version 3 of the Master Chemical Mechanism (MCM v3). This is complementary to the treatment of 107 non-aromatic VOC, presented in a companion paper. The protocol is divided into a series of subsections describing initiation reactions, the degradation chemistry to first generation products via a number of competitive routes, and the further degradation of first and subsequent generation products. Emphasis is placed on describing where the treatment differs from that applied to the non-aromatic VOC. The protocol is based on work available in the open literature up to the beginning of 2001, and some other studies known by the authors which were under review at the time. PhotoChemical Ozone Creation Potentials (POCP) have been calculated for the 18 aromatic VOC in MCM v3 for idealised conditions appropriate to north-west Europe, using a photoChemical trajectory model. The POCP values provide a measure of the relative ozone forming abilities of the VOC. These show distinct differences from POCP values calculated previously for the aromatics, using earlier versions of the MCM, and reasons for these differences are discussed.
Heinz Pitsch - One of the best experts on this subject based on the ideXlab platform.
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optimized Chemical Mechanism for combustion of gasoline surrogate fuels
Combustion and Flame, 2015Co-Authors: Liming Cai, Heinz PitschAbstract:Abstract Since real petroleum fuels are composed of a huge variety of hydrocarbon components, surrogate mixtures of various hydrocarbon fuels are typically employed in computational research and in engine development to represent transportation fuels. In this study, a reduced combustion Mechanism of Primary Reference Fuel (PRF) mixtures (n-heptane and iso-octane) is integrated into the published kinetic model (Narayanaswamy et al., 2010), allowing for the formulation of multi-component surrogate fuels (e.g. PRF/toluene) and for the prediction of Polycyclic Aromatic Hydrocarbon (PAH) formation in gasoline engines. In order to optimize the model performance, a recently developed optimization technique based on rate rules (Cai and Pitsch, 2014) is extended in this study. The goal is to calibrate automatically the multi-component kinetic Mechanism, which also leads to a Chemically consistent PRF Mechanism and a computational advantage for the calibration process. In addition, this work contributes to the development of general rate rules for various hydrocarbon fuels. An ethanol model is also incorporated into the proposed Mechanism. This facilitates the prediction of gasoline/ethanol blend combustion. The resulting Mechanism retains a compact size and is successfully validated against experimental measurements.
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a Chemical Mechanism for low to high temperature oxidation of n dodecane as a component of transportation fuel surrogates
Combustion and Flame, 2014Co-Authors: Krithika Narayanaswamy, Heinz Pitsch, Perrine PepiotAbstract:Using surrogate fuels in lieu of real fuels is an appealing concept for combustion studies. A major limitation however, is the capability to design compact and reliable kinetic models that capture all the specificities of the simpler, but still multi-component surrogates. This task is further complicated by the fairly large nature of the hydrocarbons commonly considered as potential surrogate components, since they typically result in large detailed reaction schemes. Towards addressing this challenge, the present work proposes a single, compact, and reliable Chemical Mechanism, that can accurately describe the oxidation of a wide range of fuels, which are important components of surrogate fuels. A well-characterized Mechanism appropriate for the oxidation of smaller hydrocarbon species [G. Blanquart, P. Pepiot-Desjardins, H. Pitsch, Chemical Mechanism for high temperature combustion of engine relevant fuels with emphasis on soot precursors, Combust. Flame 156 (2009) 588–607], and several substituted aromatic species [K. Narayanaswamy, G. Blanquart, H. Pitsch, A consistent Chemical Mechanism for the oxidation of substituted aromatic species, Combust. Flame 157 (10) (2010) 1879–1898], ideally suited as a base to model surrogates, has now been extended to describe the oxidation of n-dodecane, a representative of the paraffin class, which is often used in diesel and jet fuel surrogates. To ensure compactness of the kinetic scheme, a short Mechanism for the low to high temperature oxidation of n-dodecane is extracted from the detailed scheme of Sarathy et al. [S. M. Sarathy, C. K.Westbrook, M. Mehl, W. J. Pitz, C. Togbe, P. Dagaut, H. Wang, M. A. Oehlschlaeger, U. Niemann, K. Seshadri, Comprehensive Chemical kinetic modeling of the oxidation of 2-methylalkanes from C7 to C20, Combust. Flame 158 (12) (2011) 2338–2357] and integrated in a systematic way into the base model. Rate changes based on recent rate recommendations from literature are introduced to the resulting Chemical Mechanism in a consistent manner, which improve the model predictions. Extensive validation of the revised kinetic model is performed using a wide range of experimental conditions and data sets.
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a consistent Chemical Mechanism for oxidation of substituted aromatic species
Combustion and Flame, 2010Co-Authors: Krithika Narayanaswamy, Guillaume Blanquart, Heinz PitschAbstract:Abstract Computational studies of combustion in engines are typically performed by modeling the real fuel as a surrogate mixture of various hydrocarbons. Aromatic species are crucial components in these surrogate mixtures. In this work, a consistent Chemical Mechanism to predict the high temperature combustion characteristics of toluene, styrene, ethylbenzene, 1,3-dimethylbenzene (m-xylene), and 1-methylnaphthalene is presented. The present work builds on a detailed Chemical Mechanism for high temperature oxidation of smaller hydrocarbons developed by Blanquart et al. [Combust. Flame 156 (2009) 588–607]. The base Mechanism has been validated extensively in the previous work and is now extended to include reactions of various substituted aromatic compounds. The reactions representing oxidation of the aromatic species are taken from the literature or are derived from those of the lower aromatics or the corresponding alkane species. The Chemical Mechanism is validated against plug flow reactor data, ignition delay times, species profiles measured in shock tube experiments, and laminar burning velocities. The combustion characteristics predicted by the Chemical model compare well with those available from experiments for the different aromatic species under consideration.
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Chemical Mechanism for high temperature combustion of engine relevant fuels with emphasis on soot precursors
Combustion and Flame, 2009Co-Authors: Guillaume Blanquart, P Pepiotdesjardins, Heinz PitschAbstract:This article presents a Chemical Mechanism for the high temperature combustion of a wide range of hydrocarbon fuels ranging from methane to iso-octane. The emphasis is placed on developing an accurate model for the formation of soot precursors for realistic fuel surrogates for premixed and diffusion flames. Species like acetylene (C_2H_2), propyne (C_3H_4), propene (C_3H_6), and butadiene (C_4H_6) play a major role in the formation of soot as their decomposition leads to the production of radicals involved in the formation of Polycyclic Aromatic Hydrocarbons (PAH) and the further growth of soot particles. A Chemical kinetic Mechanism is developed to represent the combustion of these molecules and is validated against a series of experimental data sets including laminar burning velocities and ignition delay times. To correctly predict the formation of soot precursors from the combustion of engine relevant fuels, additional species should be considered. One normal alkane (n-heptane), one ramified alkane (iso-octane), and two aromatics (benzene and toluene) were chosen as Chemical species representative of the components typically found in these fuels. A sub-Mechanism for the combustion of these four species has been added, and the full Mechanism has been further validated. Finally, the Mechanism is supplemented with a sub-Mechanism for the formation of larger PAH molecules up to cyclo[cd]pyrene. Laminar premixed and counterflow diffusion flames are simulated to assess the ability of the Mechanism to predict the formation of soot precursors in flames. The final Mechanism contains 149 species and 1651 reactions (forward and backward reactions counted separately). The Mechanism is available with thermodynamic and transport properties as supplemental material.