The reduction of fuel consumption and the reduction of toxic emissions are the main goals of research and development in the area of internal combustion engines. The use of exhaust gas recirculation (EGR) to come further in that direction is today an established method for diesel engines. EGR reduces the emissions of nitrogen oxides with a low penalty in fuel consumption. The increasingly hard regulations on emissions put high pressure on the manufacturers to improve these systems. The present work aims at increasing the knowledge in the area of EGR. Two of the main challenges when applying EGR are addressed, efficiency and mixing. The efficiency of the EGR-system is analyzed, focusing on keeping the fuel penalty low for a given EGR-rate. Different layouts of the EGR system are studied and compared regarding their stationary and transient properties. Exergy analysis is used to show the potential for improvement in different system components. In the same time, exergy analysis as a tool is introduced and compared to energy analysis of a system. The usefulness of exergy analysis of the entire gas exchange is shown by the example of a heavy-duty diesel engine. The problem of EGR and air mixing is approached by a detailed study of the mixing process in a heavy-duty diesel engine. Different methods for the measurement of EGR distribution are presented and compared. Additionally, the possibility to predict the mixing effects by 1-D and 3-D simulation is assessed. It is shown that the mixing between air and EGR is highly dependent on the pulsating nature of the flow. The EGR is shown to be transported in packets in the air flow. This leads to the conclusion that mixing not only at the mixing point, but also mixing in flow direction needs to be optimized, as the distribution of EGR between the cylinders is dependent on the timing between the passage of the EGR packets and the valve opening time. / <p>QC 20140203</p>

Because of environmental pollution, forces the automotive industry constantly reduced emissions requirements legislated by the authorities. Improved techniques for engine control are a must for bringing down emissions. The use of an Exhaust Gas Recirculation (EGR) reduces NOx emissions significantly. Faulty EGR valves affect the emissions negative and therefore needs to be eliminated. It is possible to create malfunctions on the EGR valve by modifying the software of the control unit (ECU), but it does not create realistic malfunctions. The problem by modifying the software is that flags and various parameters are set to confirm the malfunction of the ECU. To create actual failure of the EGR valve an external tool to modify the control signal is needed. The project's main objective is on a flexible way creating malfunctions on the EGR valve in a truck engine. By investigating engine behavior in a realistic and credible way, one can eliminate malfunctions on the EGR valve. The aim was achieved by a model that has been developed that can, using electronics and a microprocessor read and create a control signal. The electronic circuit is controlled by the microprocessor, which can modify the signal and create malfunctions in the form of a slow valve "slow-response". A graphical user interface is used to change and influence the error signal. The circuit with the microprocessor is placed safely in a box to both protect and preserve the components. Simulation of Slow response has resulted in an incorrect operated valve being created. Using two different methods a Slow-response can be created. One method is a delay in time, which occurs when the new position is given, the second method is a ramp function when the control signal is gradually increasing. The software can also create an error that mimics a stuck valve of a fixed value. With the above listed methods it is possible in theory to find unknown malfunctions on the EGR valve that influence emissions negatively.

No description available.

[EN] The use of Exhaust Gas Recirculation (EGR) as a technique to reduce nitrogen oxides emissions (NOx) in Diesel engines started with the EURO regulations and continues to the present day. While aftertreatment systems were proposed as an alternative to replace EGR, the combination of both technologies has achieved the current strict regulations (EURO6, TIER 2). The fact that EGR reduces NOx originated into the combustion process with high effectiveness and with easy implementation in the engine, are the most important advantages which have kept EGR as one of the main techniques against NOx. Additionally, from another point of view, the use of EGR is spreading in other applications such as SI engines and HCCI, as a strategy to manage functional tasks on them. So far, the cooled high pressure EGR system (HPEGR) has been the most widespread configuration to perform EGR. Nonetheless, it is limited in achieving high EGR rates by its effects on Tintake, BSFC and particulate emissions (PM). In this context, low pressure EGR (LPEGR) was raised as an alternative to overcome these limitations. However, LPEGR has other disadvantages such as low value of Pexh-intk which prevents high EGR rates during some engine conditions or the effect on other pollutant emissions during engine warm up at the emissions cycle. Considering the new challenges that light vehicles will face in the future regulations (WLTP or TIER 3) and the aforementioned individual limitations for HPEGR and LPEGR systems, this PhD. Thesis propounds the analysis of the combination of both EGR techniques, HPEGR and LPEGR, in order to show the ability to reach high EGR rates and the effects on fuel consumption and pollutant emissions. To accomplish this objective, by means of experimental tests, two different combination strategies are evaluated: firstly, a simultaneous combination of both HPEGR and LPEGR systems and, secondly, a sequential combination of the individual systems. For simultaneous combination of HPEGR and LPEGR, a sweep of EGR rates combining the use of both systems is performed at five engine operation points within the engine operating range of EGR. For all tested points, the ability of reaching higher rates of EGR with the combination than with individual systems is analyzed from the air management point of view. The analysis is performed by studying the evolution of the properties of the trapped mass into the cylinder, the engine volumetric efficiency and the turbocharger performance. Besides analyzing the evolution of BSFC and pollutant emissions. Regarding the sequential combination of HPEGR and LPEGR, various tests of the NEDC emission cycle are performed in different ambient temperatures (20ºC, 0ºC and -7ºC). The sequential combination strategy involves starting the test cycle with HPEGR and, after a given time (600s and 800s), switching to LPEGR system. For these tests, the engine warm up evolution and pollutant emissions evolution are analyzed. Finally, as a practical contribution, an estimation technique of LPEGR mass flow is proposed by means of an energy balance into the control volume defined at the joint between the LPEGR and the fresh air ducts, just before the compressor intake. / [ES] El uso de la técnica de Recirculación de Gases de Escape (EGR) para la reducción de las emisiones de óxidos de nitrógeno (NOx) en motores Diésel se inicia con las primeras normativas EURO y se extiende hasta hoy en día. Si bien los sistemas post-tratamiento se planteaban como alternativa para sustituir al EGR, finalmente, ambas tecnologías se han complementado para lograr alcanzar las estrictas limitaciones impuestas por las actuales normativas vigentes (EURO6, TIER 2). El hecho de que el EGR actúe en la reducción de NOx desde su origen en el proceso de combustión de forma efectiva y la simplicidad de ser implementado en un motor, han sido algunas de las ventajas que han mantenido al EGR como una de las principales técnicas contra los NOx. Además, desde otro punto de vista, el uso del EGR se está extendiendo en otras aplicaciones como los MEP o HCCI para gestionar estrategias de funcionamiento propias de dichas motorizaciones. Hasta ahora el EGR de alta presión refrigerado (HPEGR) había sido la configuración más generalizada para llevar a cabo la tasa de EGR. Sin embargo, se ve limitado para alcanzar altas tasas de EGR por su efecto en la Tadm, el incremento del gef o en las emisiones de partículas (PM). Ante esta situación, se planteaba el EGR de baja presión (LPEGR) como alternativa para superar estas limitaciones, aunque conlleva otras desventajas como el bajo valor de Pesc-adm que impide realizar altas tasas de EGR o su efecto sobre otras emisiones contaminante durante el calentamiento motor en el ciclo de homologación. En el marco de los nuevo retos a los que se enfrentan los vehículos ligeros con las futuras normativas (WLTP o TIER 3) y con las citadas limitaciones individuales de los sistemas HPEGR y LPEGR, en esta Tesis Doctoral se plantea el análisis de la combinación de las técnicas de EGR de alta y baja presión para alcanzar altas tasas de EGR y sus efectos sobre el consumo y las emisiones. Para llevar a cabo este objetivo, desde el punto de vista experimental, se plantean dos estrategias diversas de combinación: por una parte la combinación simultánea de ambos sistemas y por otra la combinación secuencial. Para la combinación simultánea de los sistemas de HPEGR y LPEGR, se realiza un barrido de combinación de ambos sistemas en cinco puntos de funcionamiento del motor dentro del área de EGR. Para todos los puntos ensayados se analiza la capacidad de realizar mayores tasas de EGR que los sistemas individuales, desde el punto de vista de la renovación de la carga. Dicho análisis se lleva a cabo mediante el estudio de la evolución de las propiedades de la masa atrapada en el cilindro, el rendimiento volumétrico y las condiciones de funcionamiento del turbocompresor. Además se analizan las evoluciones del gef y de las emisiones contaminantes. Respecto a la combinación secuencial de HPEGR y LPEGR, se realizan diversos ensayos de un ciclo de homologación NEDC a distintas temperaturas de funcionamiento (20ºC, 0ºC y -7ºC). La estrategia de combinación secuencial implica empezar el ciclo de homologación con el sistema HPEGR y en determinado instante del ciclo (600s y 800s) cambiar al sistema LPEGR. Para estos ensayos se ha realizado el estudio de la evolución del calentamiento motor y el efecto en las emisiones de NOx. / [CA] L'ús de la tècnica de Recirculació de Gasos d'Escapament (EGR) per a la reducció de les emissions d'òxids de nitrogen en motors Dièsel s'inicia amb les primeres normatives EURO i s'ha anat utilitzant fins l'actualitat. Si bé els sistemes post-tractament es plantejaven com a alternativa per a substituir al EGR, finalment ambdós tecnologies s'han complementat per a aconseguir les estrictes limitacions imposades a hores d'ara (EURO6, TIER 2). El fet de que l'EGR actua en la reducció de NOx des del seu origen en el procés de combustió de forma efectiva i la simplicitat per a ser implementat en un motor, han sigut alguns dels avantatges que han mantingut al EGR com una de les principals tècniques contra els NOx. A més, des d'un altre punt de vista, s'està estenent l'ús del EGR en altres aplicacions com en els MEP o HCCI per a gestionar estratègies de funcionament pròpies de dites motoritzacions. Fins ara l'EGR d'alta pressió refrigerat (HPEGR) havia sigut la configuració més generalitzada per a dur a terme la taxa de EGR. No obstant, això es veu limitat per a aconseguir altes taxes d'EGR pel seu efecte en la Tadm, l'increment del gef o en les emissions de partícules (PM). Davant d'aquesta situació, es planteja l'EGR de baixa pressió (LPEGR) com a alternativa per a superar estes limitacions, encara que comporta altres desavantatges com el seu efecte a les altres emissions en condicions de funcionament de motor fred o el baix valor de Pesc-adm que impedix realitzar altes taxes de EGR. En el marc dels nous reptes als què s'enfronten els vehicles lleugers amb les futures normatives (WLTP o TIER 3) i de les esmentades limitacions individuals dels sistemes HPEGR i LPEGR, en esta Tesi Doctoral es planteja l'anàlisi de la combinació de les tècniques de EGR d'alta i baixa pressió per a aconseguir altes taxes de EGR, des del punt de vista del procés de renovació de la càrrega, i els seus efectes sobre el consum i les emissions. Per a dur a terme este objectiu es plantegen dos estratègies diverses de combinació: d'una banda la combinació simultània d'ambdós sistemes i per una altra la combinació seqüencial. Per a la combinació simultània dels sistemes de HPEGR i LPEGR, es realitza un mostreig de combinació d'ambdós sistemes en cinc punts dins de l'àrea de EGR del motor. Per a tots els punts assajats es realitza una anàlisi de la capacitat de realitzar majors taxes de EGR que els sistemes individuals, des del punt de vista de la renovació de la càrrega. Aquest anàlisi es du a terme per mitjà de l'estudi de l'evolució de les propietats de la massa atrapada en el cilindre, el rendiment volumètric i les condicions de funcionament del turbocompressor. A més es realitza l'anàlisi de les evolucions del gef i de les emissions contaminants. Respecte a la combinació seqüencial de HPEGR i LPEGR, es realitzen diversos assajos d'un cicle d'homologació NEDC a distintes temperatures de funcionament (20ºC, 0ºC i -7ºC). L'estratègia de combinació seqüencial implica comen car el cicle d'homologació amb el sistema HPEGR i en determinat instant del cicle (600s i 800s) canviar al sistema LPEGR. Per a estos assajos s'ha realitzat l'estudi de l'evolució del calfament del motor i l'efecte en les emissions de NOx. Finalment, com a aportació pràctica, es planteja una tècnica d'estimació de gast màsic de LPEGR. per mitjà del balanç energètic en el volum de control definit en la unió del sistema de LPEGR amb el conducte d'aire fresc abans del compressor. / Soler Muniesa, JA. (2016). Análisis de la combinación de los sistemas de recirculación de gases de Alta y Baja presión sobre el comportamiento de un motor Diesel sobrealimentado [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/62198

<p>To fulfil emission requirements specified by environment demands, such as Euro 4 and Euro 5, there is a need to utilize engines based on technologies such as Variable Turbine Geometry (VGT) and Exhaust Gas Recirculation (EGR). A model of an engine using VGT and EGR was created by Ph.D student Johan Wahlström at Linköping University. This thesis evaluates Wahlström's model and shows how it successfully describes the engine and its behaviour. The thesis also confirms theories about the occurrens of non.minimum phase behaviour in different transfer functions, e.g. from VGT signal to the mass flow through the compressor.</p><p>An interesting phenomenon when applying VGT and EGR is a nonlinearity leading to, for example, that the same pressure in the intake manifold can occur for two different VGT signals. Such phenomenon can cause problems when designing a control system. Furthermore, this nonlinearity also results in a replacement of the nonminimum phase behaviour with an overshoot when a large (above 80%) VGT control signal is used.</p><p>This thesis also provides a linearized model, which describes the engine satisfactory. The linearization results in transfer functions with two zeros and three poles, whose locations do not change much when varying engine speed and load (except at high load and low engine speed). This fact will most likely make it possible to utilize just a few different linearizations for all speeds and loads. However, altering VGT and EGR positions greatly affect the transfer functions. Thus, several linearizations are probably needed to cover all operating points.</p><p>When designing a future control system a good strategy is to utilize a decoupled system since the model has strong cross-connections. Another solution would be to apply multi dimensional control strategy, e.g. LQ-theory.</p>

The recent pollution norms have brought a strong emphasis on the reduction of diesel engine emissions. Low temperature combustion technology such as premixed compression ignition (PCI) has the capability to significantly and simultaneously reduce nitric oxides (NOx) and particulate matter (PM), thus meeting these specific pollution norms. There has been, however, observed loss in fuel conversion efficiency in some cases. This study analyzes how energy transfer and brake fuel conversion efficiency alter with (or are affected by) injection timings and exhaust gas recirculation (EGR) rate. The study is conducted for PCI combustion for four injection timings of 9°, 12°, 15° and 18° before top dead center (BTDC) and for four exhaust gas recirculation (EGR) rates of 39%, 40%, 41% and 42%. The data is collected from the experimental apparatus located in General Motors Collaborative Research Laboratory at the University of Michigan. The heat release is calculated to obtain various in-cylinder energy transfers. The brake fuel conversion efficiency decreases with an increase in EGR. The decrease in the brake fuel conversion efficiency is due to the decrease in work output. This decrease is due to an increase in the pumping work and an increase in friction and decrease in gross indicated work. The decrease in the combustion efficiency is because of the increased formation of unburnt products due to increased ignition delay caused by the application of EGR and decreasing air-fuel (A/F) ratio. A definite trend is not obtained for the contribution of heat transfer to the total energy distribution. However the total heat transfer decreases with retardation of injection timing because of decreasing combustion temperature. As the injection timing is retarded, the brake fuel conversion efficiency is found to decrease. This decrease is because of a decrease in net work output. This is because the time available for utilization of the energy released is less because of late combustion. The total heat transfer decreases with retardation of injection timing because of decreasing combustion temperature. The contribution of heat transfer to the total energy distribution decreases with increase in EGR.

To fulfil emission requirements specified by environment demands, such as Euro 4 and Euro 5, there is a need to utilize engines based on technologies such as Variable Turbine Geometry (VGT) and Exhaust Gas Recirculation (EGR). A model of an engine using VGT and EGR was created by Ph.D student Johan Wahlström at Linköping University. This thesis evaluates Wahlström's model and shows how it successfully describes the engine and its behaviour. The thesis also confirms theories about the occurrens of non.minimum phase behaviour in different transfer functions, e.g. from VGT signal to the mass flow through the compressor. An interesting phenomenon when applying VGT and EGR is a nonlinearity leading to, for example, that the same pressure in the intake manifold can occur for two different VGT signals. Such phenomenon can cause problems when designing a control system. Furthermore, this nonlinearity also results in a replacement of the nonminimum phase behaviour with an overshoot when a large (above 80%) VGT control signal is used. This thesis also provides a linearized model, which describes the engine satisfactory. The linearization results in transfer functions with two zeros and three poles, whose locations do not change much when varying engine speed and load (except at high load and low engine speed). This fact will most likely make it possible to utilize just a few different linearizations for all speeds and loads. However, altering VGT and EGR positions greatly affect the transfer functions. Thus, several linearizations are probably needed to cover all operating points. When designing a future control system a good strategy is to utilize a decoupled system since the model has strong cross-connections. Another solution would be to apply multi dimensional control strategy, e.g. LQ-theory.

The recent pollution norms have brought a strong emphasis on the reduction of diesel engine emissions. Low temperature combustion technology such as premixed compression ignition (PCI) has the capability to significantly and simultaneously reduce nitric oxides (NOx) and particulate matter (PM), thus meeting these specific pollution norms. There has been, however, observed loss in fuel conversion efficiency in some cases. This study analyzes how energy transfer and brake fuel conversion efficiency alter with (or are affected by) injection timings and exhaust gas recirculation (EGR) rate. The study is conducted for PCI combustion for four injection timings of 9°, 12°, 15° and 18° before top dead center (BTDC) and for four exhaust gas recirculation (EGR) rates of 39%, 40%, 41% and 42%. The data is collected from the experimental apparatus located in General Motors Collaborative Research Laboratory at the University of Michigan. The heat release is calculated to obtain various in-cylinder energy transfers. The brake fuel conversion efficiency decreases with an increase in EGR. The decrease in the brake fuel conversion efficiency is due to the decrease in work output. This decrease is due to an increase in the pumping work and an increase in friction and decrease in gross indicated work. The decrease in the combustion efficiency is because of the increased formation of unburnt products due to increased ignition delay caused by the application of EGR and decreasing air-fuel (A/F) ratio. A definite trend is not obtained for the contribution of heat transfer to the total energy distribution. However the total heat transfer decreases with retardation of injection timing because of decreasing combustion temperature. As the injection timing is retarded, the brake fuel conversion efficiency is found to decrease. This decrease is because of a decrease in net work output. This is because the time available for utilization of the energy released is less because of late combustion. The total heat transfer decreases with retardation of injection timing because of decreasing combustion temperature. The contribution of heat transfer to the total energy distribution decreases with increase in EGR.

Les normes européennes EURO 5 / EURO 6 de réduction des émissions polluantes des véhicules automobile sont de plus en plus sévères. La boucle de recirculation des gaz d’échappement, dite boucle EGR (Exhaust Gas Recirculation), est une solution de dépollution à la source car elle réduit les quantités émises d’oxydes d’azote et de particules de suie. Ce contexte entraîne une utilisation plus intensive de la boucle EGR, d’où une augmentation de son encrassement. Assurer la fiabilité de cette boucle est un enjeu important pour les constructeurs automobiles. Un montage expérimental dont on contrôle les conditions opératoires a été conçu pour recréer les dépôts observés dans l'échangeur EGR d'un moteur Diesel. Il permet de déterminer les paramètres pilotant la formation et l’évolution du dépôt d'encrassement, via une mesure de sa masse, une analyse de sa composition chimique et un suivi des transferts thermiques (thermocouples, caméra infra rouge) dans l’échangeur au cours du temps. / The EURO 5 and EURO 6 European norms on the vehicle pollutant emission reduction are stricter than the previous. The Exhaust Gas Recirculation system, also called as EGR system, is a solution for the remediation at source, because it reduces the quantity of emitted nitrogen oxides and soot particles. The resulting intensive use of the EGR system increases the fouling in the involved heat exchanger. Ensuring the reliability of the EGR system is an important challenge for car manufacturers. An experimental set-up, with controlled operating conditions, has been built to recreate the deposit observed in the EGR heat-exchanger of Diesel engines. It enables to determine the parameters driving the fouling deposit formation and evolution, via a weight measurement, a chemical composition analysis and a follow-up of the thermal transfer (thermocouples, IR camera) in the heat-exchanger over the time.

La réduction des émissions de CO2 et de polluants est un des enjeux essentiels pour faire face aux problèmes liés au changement climatique. Dans le secteur des transports, la technologie de recirculation des gaz d’échappement (EGR) est souvent utilisée dans les moteurs turbo-compressés à allumage commandé pour réduire la consommation de carburant, inhiber les risques de cliquetis et réduire les émissions de NOx. Cependant, des taux d’EGR élevés restent difficiles à atteindre car ils réduisent le dégagement de chaleur et la stabilité du moteur. L'augmentation du niveau de turbulence et la mise en oeuvre de systèmes à allumage commandé avancés n’apportant pas d'améliorations suffisantes dans des conditions aussi extrêmes, la chimie de la combustion pour les très hautes dilutions suscite un intérêt croissant. Le présent travail vise à comprendre la chimie de combustion des flammes prémélangées essence/air très diluées et à établir un mécanisme cinétique détaillé par modélisation multi-échelle afin de prévoir les caractéristiques de combustion avec une précision suffisante dans des conditions de forte dilution.Ce travail adopte une approche de modélisation multi-échelle et cible la vitesse de flamme laminaire (SL) d'un substitut d'essence, appelé TRFE et qui est constitué d'isooctane, de n-heptane, de toluène et d'éthanol. Pour la modélisation à l’échelle microscopique, la réaction entre le cétène et le radical hydroxyle, qui pourrait être importante pour la SL dans des conditions très diluées, est étudiée théoriquement à l'aide de méthodes de structure électronique ab initio pour la surface d'énergie potentielle (PES) et Rice -- Ramsperger -- Kassel -- Marcus Theory couplé à l'équation maîtresse (RRKM / ME) pour les coefficients de vitesse. Des PES détaillées sont obtenues, les voies dominantes sont identifiées et leurs coefficients de vitesse phénoménologiques sont dérivés pour être utilisés dans la modélisation de la combustion. Pour la modélisation à l'échelle macroscopique, les paramètres cinétiques, thermodynamiques et de transport importants pour la vitesse de la flamme laminaire dans des conditions très diluées sont d'abord identifiés à l'aide d'une analyse de sensibilité réalisée sur une version initiale du mécanisme TRFE de départ. Les réactions sensibles impliquent principalement HO2, les espèces C2 - C3 et des radicaux issus du carburant. Le mécanisme initial, via un travail spécifique à chacun des sous-mécanismes, est mis à jour à l'aide des paramètres cinétiques les plus récents issus de la littérature. Enfin, un mécanisme détaillé adapté aux calculs de vitesse de flamme laminaire dans des conditions de forte dilution est validé. Une corrélation mathématique de SL est établie pour l'utilisation dans des simulations numériques de la dynamique des fluides (CFD). / Reducing CO2 and pollutant emission is the essential challenge when dealing with climate change problems. In the transport sector, exhaust gas recirculation (EGR) technology is often used in turbocharged gasoline spark ignition (SI) engines to increase fuel economy, inhibit knock tendency, and reduce NOx emissions. However, high EGR ratios are still difficult to achieve, as they result in reduced heat release and engine stability. As increasing turbulence level and advance spark ignition systems could not bring sufficient improvements at such extreme conditions, growing interest is cast onto the combustion chemistry under high dilution. The present work aims to understand the combustion chemistry of highly-diluted gasoline premixed flames and to establish a detailed kinetic mechanism by multi-scale modeling to predict combustion characteristics with sufficient accuracy at highly-diluted conditions.This work adopts a multi-scale modeling approach, and targets on the laminar flame speed (SL) of a gasoline surrogate, which is named toluene reference fuel with ethanol addition (TRFE) and consist of isooctane, n-heptane, toluene, and ethanol. For micro-scale modeling, the reaction between ketene and hydroxyl radical, which might be important to the SL at highly-diluted conditions, is studied theoretically using ab initio electronic structure methods for the potential energy surface (PES) and Rice–Ramsperger–Kassel–Marcus Theory coupled with Master Equation (RRKM/ME) for the rate coefficients. Detailed PES is obtained, dominant pathways are identified, and their phenomenological rate coefficients are derived to be utilized in combustion modeling. For macro-scale modeling, firstly, important kinetic, thermodynamic, and transport parameters to the laminar flame speed at highly-diluted conditions, are firstly identified using sensitivity analysis based on a starting mechanism. Sensitive reactions are found to mostly involve HO2, C2--C3 species and fuel radicals. Secondly, in the sub-mechanisms where these reactions lies, diluted flames of the corresponding fuels are studied and chemical detail of the dilution effects are explored. The starting mechanism is updated by state-of-the-art kinetics parameters found in the literature for each sub-mechanisms. Finally, a detailed mechanism suitable for laminar flame speed calculations at highly-diluted conditions is established after validation. A mathematical SL correlation is generated for the use in computational fluid dynamic (CFD) simulations.