Download or read book Multi dimensional Modeling of Ignition and Combustion in Premixed and DIS CI direct Injection Spark compression Ignition Engines written by Zhichao Tan and published by . This book was released on 2003 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Multidimensional Modeling of Combustion and Knock in Spark ignition Engines with Detailed Chemical Kinetics written by Long Liang and published by . This book was released on 2006 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Multi dimensional Modeling of Natural Gas Ignition Combustion and Pollutant Formation in Direct Injection Engines written by Apoorva Agarwal and published by . This book was released on 1998 with total page 410 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Multi dimensional Modeling of Mixing and Combustion of Direct Injection Spark Ignition Engines written by Li Fan and published by . This book was released on 2000 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modelling Spark Ignition Combustion written by P. A. Lakshminarayanan and published by Springer Nature. This book was released on with total page 678 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Multidimensional Modeling of Ignition and Combustion in Spark igniton Engines Based on Level set Approach written by Guangfei Zhu and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: An LES version ignition model, WSSIM, was developed by taking the effect of turbulence on wrinkling and stretching the flame surface into account. Next, this ignition model was combined with an innovative swept-volume algorithm based combustion model to simulate the cycle to cycle variations of ignition and combustion processes in premixed propane/air mixtures. The open source software OpenFOAM-5.0 helped to implement and validate the models.

Download or read book Gasoline Compression Ignition Technology written by Gautam Kalghatgi and published by Springer Nature. This book was released on 2022-01-17 with total page 339 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on gasoline compression ignition (GCI) which offers the prospect of engines with high efficiency and low exhaust emissions at a lower cost. A GCI engine is a compression ignition (CI) engine which is run on gasoline-like fuels (even on low-octane gasoline), making it significantly easier to control particulates and NOx but with high efficiency. The state of the art development to make GCI combustion feasible on practical vehicles is highlighted, e.g., on overcoming problems on cold start, high-pressure rise rates at high loads, transients, and HC and CO emissions. This book will be a useful guide to those in academia and industry.

Download or read book A Multi dimensional Flamelet Model for Ignition in Multi feed Combustion Systems written by Eric Michael Doran and published by Stanford University. This book was released on 2011 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work develops a computational framework for modeling turbulent combustion in multi-feed systems that can be applied to internal combustion engines with multiple injections. In the first part of this work, the laminar flamelet equations are extended to two dimensions to enable the representation of a three-feed system that can be characterized by two mixture fractions. A coupling between the resulting equations and the turbulent flow field that enables the use of this method in unsteady simulations is then introduced. Models are developed to describe the scalar dissipation rates of each mixture fraction, which are the parameters that determine the influence of turbulent mixing on the flame structure. Furthermore, a new understanding of the function of the joint dissipation rate of both mixture fractions is discussed. Next, the extended flamelet equations are validated using Direct Numerical Simulations (DNS) of multi-stream ignition that employ detailed finite-rate chemistry. The results demonstrate that the ignition of the overall mixture is influenced by heat and mass transfer between the fuel streams and that this interaction is manifested as a front propagation in two-dimensional mixture fraction space. The flamelet model is shown to capture this behavior well and is therefore able to accurately describe the ignition process of each mixture. To provide closure between the flamelet chemistry and the turbulent flow field, information about the joint statistics of the two mixture fractions is required. An investigation of the joint probability density function (PDF) was carried out using DNS of two scalars mixing in stationary isotropic turbulence. It was found that available models for the joint PDF lack the ability to conserve all second-order moments necessary for an adequate description of the mixing field. A new five parameter bivariate beta distribution was therefore developed and shown to describe the joint PDF more accurately throughout the entire mixing time and for a wide range of initial conditions. Finally, the proposed model framework is applied in the simulation of a split-injection diesel engine and compared with experimental results. A range of operating points and different injection strategies are investigated. Comparisons with the experimental pressure traces show that the model is able to predict the ignition delay of each injection and the overall combustion process with good accuracy. These results indicate that the model is applicable to the range of regimes found in diesel combustion.

Download or read book Assessment of Fuel Economy Technologies for Light Duty Vehicles written by National Research Council and published by National Academies Press. This book was released on 2011-06-03 with total page 373 pages. Available in PDF, EPUB and Kindle. Book excerpt: Various combinations of commercially available technologies could greatly reduce fuel consumption in passenger cars, sport-utility vehicles, minivans, and other light-duty vehicles without compromising vehicle performance or safety. Assessment of Technologies for Improving Light Duty Vehicle Fuel Economy estimates the potential fuel savings and costs to consumers of available technology combinations for three types of engines: spark-ignition gasoline, compression-ignition diesel, and hybrid. According to its estimates, adopting the full combination of improved technologies in medium and large cars and pickup trucks with spark-ignition engines could reduce fuel consumption by 29 percent at an additional cost of $2,200 to the consumer. Replacing spark-ignition engines with diesel engines and components would yield fuel savings of about 37 percent at an added cost of approximately $5,900 per vehicle, and replacing spark-ignition engines with hybrid engines and components would reduce fuel consumption by 43 percent at an increase of $6,000 per vehicle. The book focuses on fuel consumption-the amount of fuel consumed in a given driving distance-because energy savings are directly related to the amount of fuel used. In contrast, fuel economy measures how far a vehicle will travel with a gallon of fuel. Because fuel consumption data indicate money saved on fuel purchases and reductions in carbon dioxide emissions, the book finds that vehicle stickers should provide consumers with fuel consumption data in addition to fuel economy information.

Download or read book A Multi regime Combustion Model for Reactive Flow in Internal Combustion Engines written by Varun Mittal and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: With the ever-rising need for better fuel efficiency and lower emissions, the development of better engine technologies is essential. Developing these technologies requires a good understanding of the interaction between the various coupled multi-physics phenomena present in the engine. Detailed simulations of the engine can potentially provide this. Such simulations are becoming tractable now with the increase in available computational power. Since the combustion process is the primary controlling feature in these engines, an accurate combustion model is essential for enabling these simulations. This model must be efficient and valid across different combustion regimes, since modern engines might operate in hybrid modes. In this work, a framework for studying combustion in engines is developed. In the first part of this work, the focus is on the premixed regime which is dominant in Spark Ignited (SI) engines. The canonical flamelet model used extensively to study constant pressure premixed combustion is extended to variable pressure conditions that are observed in an engine cylinder. An extrapolation procedure is also developed for ensuring a consistent enthalpy and temperature under strong compression. This model is validated against direct numerical simulations with detailed chemistry under different turbulence conditions. The performance of the isobaric model is also evaluated in high turbulence conditions by comparing against detailed experiments of a piloted premixed jet burner with finite rate chemistry and different turbulence levels. In the second part of this work, the autoignition regime is studied, which is the dominant regime in Homogeneous Charge Compression Ignition (HCCI) engines. The Representative Interactive Flamelet (RIF) combustion model has previously been used to describe ignition, combustion, and pollutant formation in direct-injected Diesel engines. It has also been applied successfully for HCCI type combustion. In this work, the RIF model is validated against direct numerical simulation data to evaluate model performance under mixture stratification in Diesel, HCCI, and hybrid regimes. A wide range of thermal stratification and concurrent stratification cases is considered using the model. Since mixed modes are present in a modern engine, a multi-regime combustion model is required. A model is developed in this work by integrating the models for autoignition and premixed regimes. This model is validated against direct numerical simulations with for cases both regimes are important. Finally, simulations of an actual engine are performed. First, the validity of the flow solution is tested by simulating flow bench configurations with no valve motion or reaction. Next, gas exchange simulations of a motored engine are performed. Last, simulation of mixture formation in an engine is performed.

Download or read book Modeling for SI Diesel Engines written by and published by . This book was released on 2004 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Second Law Analysis of Premixed Compression Ignition Combustion in a Diesel Engine Using a Thermodynamic Engine Cycle Simulation written by Sushil Shreekant Oak and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A second law analysis of compression ignition engine was completed using a thermodynamic engine cycle simulation. The major components of availability destruction and transfer for an entire engine cycle were identified and the influence of mode of combustion, injection timing and EGR on availability balance was evaluated. The simulation pressure data was matched with the available experimental pressure data gathered from the tests on the Isuzu 1.7 L direct injection diesel engine. Various input parameters of the simulation were changed to represent actual engine conditions. Availability destruction due to combustion decreases with advanced injection timing and under premixed compression ignition (PCI) modes; but it is found to be insensitive to the level of EGR. Similarly, trends (or lack of trends) in the other components of availability balance were identified for variation in injection timing, EGR level and mode of combustion. Optimum strategy for efficient combustion processes was proposed based on the observed trends.

Download or read book Modelling Spark Ignition Combustion written by P. A. Lakshminarayanan and published by Springer. This book was released on 2024-05-02 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book provides a comprehensive overview of combustion models used in different types of spark ignition engines. In the first generation of spark ignition (SI) engines, the turbulence is created by the shear flow passing through the intake valves, and significantly decays during the intake and compression strokes. The residual turbulence enhances the laminar flame velocity, which is characteristic of the fuel and increases the relative effectiveness of the engine. In this simple two-zone model, the turbulence is estimated empirically; the spherical flame propagation model considers ignition delay, thermodynamics, heat transfer and chemical equilibrium, to obtain the performance and emissions of an SI engine. The model is used extensively by designers and research engineers to handle the fuel-air mixture prepared in the inlet and different geometries of open combustion chambers. The empiricism of the combustion model was progressively dismantled over the years. New 3D models for ignition considering the flow near a spark plug and flame propagation in the bulk gases were developed by incorporating solutions to Reynolds-averaged Navier-Stokes (RANS) equations for the turbulent flow with chemical reactions in the intense computational fluid dynamics. The models became far less empirical and enabled treating new generation direct-injection spark-ignition (DISI) gasoline and gas engines. The more complex layout of DISI engines with passive or active prechamber is successfully handled by them. This book presents details of models of SI engine combustion progressively increasing in complexity, making them accessible to designers, researchers, and even mechanical engineers who are curious to explore the field. This book is a valuable resource for anyone interested in spark ignition combustion.

Download or read book Computer Simulation Of Compression Ignition Engine Processes written by V. Ganesan and published by Universities Press. This book was released on with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book attempts to provide a simplified framework for the vast and complex map of technical material that exists on compression-ignition engines, and at the same time include sufficient details to convey the complexity of engine simulation. The emphasis here is on the thermodynamics, combustion physics and chemistry, heat transfer, and friction processes relevant to compression-ignition engines with simplifying assumpations.

Download or read book Modeling and Simulation of Knock and Nitric Oxide Emissions in Turbocharged Direct Injection Spark Ignition Engines written by Dirk Linse and published by . This book was released on 2013-11-13 with total page 189 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advances in Compression Ignition Natural Gas Diesel Dual Fuel Engines written by Hongsheng Guo and published by Frontiers Media SA. This book was released on 2021-03-23 with total page 125 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Numerical Simulation of Combustion and Unburnt Products in Dual fuel Compression ignition Engines with Multiple Injection written by Arash Jamali and published by . This book was released on 2015 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: Natural gas substitution for diesel can result in significant reduction in pollutant emissions. Based on current fuel price projections, operating costs would be lower. With a high ignition temperature and relatively low reactivity, natural gas can enable promising approaches to combustion engine design. In particular, the combination of low reactivity natural gas and high reactivity diesel may allow for optimal operation as a reactivity-controlled compression ignition (RCCI) engine, which has potential for high efficiency and low emissions. In this computational study, a lean mixture of natural gas is ignited by direct injection of diesel fuel in a model of the heavy-duty CAT3401 diesel engine. Dual-fuel combustion of natural gas-diesel (NGD) may provide a wider range of reactivity control than other dual-fuel combustion strategies such as gasoline-diesel dual fuel. Accurate and efficient combustion modeling can aid NGD dual-fuel engine control and optimization. In this study, multi-dimensional simulation was performed using a nite-volume computational code for fuel spray, combustion and emission processes. Adaptive mesh refinement (AMR) and multi-zone reaction modeling enables simulation in a reasonable time. The latter approach avoids expensive kinetic calculations in every computational cell, with considerable speedup. Two approaches to combustion modeling are used within the Reynolds averaged Navier-Stokes (RANS) framework. The first approach uses direct integration of the detailed chemistry and no turbulence-chemistry interaction modeling. The model produces encouraging agreement between the simulation and experimental data. For reasonable accuracy and computation cost, a minimum cell size of 0.2 millimeters is suggested for NGD dual-fuel engine combustion. In addition, the role of different chemical reaction mechanism on the NGD dual-fuel combustion is considered with this model. This work considers fundamental questions regarding combustion in NGD dual-fuel combustion, particularly about how and where fuels react, and the difference between combustion in the dual fuel mode and conventional diesel mode. The results show that in part-load working condition main part of CH4 cannot burn and it has significant effect in high level of HC emission in NGD dual-fuel engine. The CFD results reveal that homogeneous mixture of CH4 and air is too lean, and it cannot ignite in regions that any species from C7H16 chemical mechanism does not exist. It is shown that multi-injection of diesel fuel with an early main injection can reduce HC emission significantly in the NGD dual-fuel engine. In addition, the results reveal that increasing the air fuel ratio by decreasing the air amount could be a promising idea for HC emission reduction in NGD dual-fuel engine, too.