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Viewing 181 to 210 of 33097
2017-03-28
Technical Paper
2017-01-0527
Arya Yazdani, Jeffrey Naber, Mahdi Shahbakhti, Paul Dice, Chris Glugla, Stephen Cooper, Douglas McEwan, Garlan Huberts
An accurate estimation of cycle-by-cycle in-cylinder mass and the composition of the cylinder charge is required for spark-ignition engine transient control strategies to obtain required torque, Air-Fuel-Ratio (AFR) and meet engine pollution regulations. Mass Air Flow (MAF) and Manifold Absolute Pressure (MAP) sensors have been utilized in different control strategies to achieve these targets; however, these sensors have response delay in transients. As an alternative to air flow metering, in-cylinder pressure sensors can be utilized to directly measure cylinder pressure, based on which, the amount of air charge can be estimated without the requirement to model the dynamics of the manifold.
2017-03-28
Technical Paper
2017-01-0529
Seamus Kane, Xuesong Li, Benjamin Wolk, Isaac Ekoto, William F. Northrop
Abstract Fuel reforming during a Negative Valve Overlap (NVO) period is an effective approach to control Low Temperature Gasoline Combustion (LTGC) ignition. Previous work has shown through experiments that primary reference fuels reform easily and produce several species that drastically affect ignition characteristics. However, our previous research has been unable to accurately predict measured reformate composition at the end of the NVO period using simple single-zone models. In this work, we use a stochastic reactor model (SRM) closed cycle engine simulation to predict reformate composition accounting for in-cylinder temperature and mixture stratification. The SRM model is less computationally intensive than CFD simulations while still allowing the use of large chemical mechanisms to predict intermediate species formation rates.
2017-03-28
Technical Paper
2017-01-0525
Namho Kim, Joohan Kim, Insuk Ko, Hoimyung Choi, Kyoungdoug Min
Abstract The role of 1D simulation tool is growing as the engine system is becoming more complex with the adoption of a variety of new technologies. For the reliability of the 1D simulation results, it is necessary to improve the accuracy and applicability of the combustion model implemented in the 1D simulation tool. Since the combustion process in SI engine is mainly determined by the turbulence, many models have been concentrating on the prediction of the evolution of in-cylinder turbulence intensity. In this study, two turbulence models which can resemble the turbulence intensity close to that of 3D CFD tool were utilized. The first model is dedicated to predicting the evolution of turbulence intensity during intake and compression strokes so that the turbulence intensity at the spark timing can be estimated properly. The second model is responsible for predicting the turbulence intensity of burned and unburned zone during the combustion process.
2017-03-28
Technical Paper
2017-01-0526
Oldrich Vitek, Jan Macek
Abstract The proposed paper deals with thermodynamic optimization of highly flexible ICE (variable compression ratio, intake/exhaust VVA) while comparing e-turbocharging concept with classical one. The e-turbocharging approach is based on idea that compressor/turbine has its own electric machine (motor/generator) and that additional electric energy can be supplied/attached from/to engine crank train. Hence it allows independent control of compressor/turbine. On the other hand, classical approach is based on a standard mechanical connection between turbine and compressor. The whole system (flexible engine + boost device) is optimized under steady operation – low load (BMEP of 4 bar), medium load (BMEP of 13 bar), high load (BMEP of 30, 25 and 18 bar) and maximum load are considered. Moreover, 3 combustion concepts are considered – classical SI and CI, and ideal RCCI.
2017-03-28
Technical Paper
2017-01-0545
Adrian Irimescu, Silvana Di Iorio, Simona Silvia Merola, Paolo Sementa, Bianca Maria Vaglieco
Abstract Multi-fuel operation is one of the main topics of investigative research in the field of internal combustion engines. Spark ignition (SI) power units are relatively easily adaptable to alternative liquid-as well as gaseous-fuels, with mixture preparation being the main modification required. Numerical simulations are used on an ever wider scale in engine research in order to reduce costs associated with experimental investigations. In this sense, quasi-dimensional models provide acceptable accuracy with reduced computational efforts. Within this context, the present study puts under scrutiny the assumption of spherical flame propagation and how calibration of a two-zone combustion simulation is affected when changing fuel type. A quasi-dimensional model was calibrated based on measured in-cylinder pressure, and numerical results related to the two-zone volumes were compared to recorded flame imaging.
2017-03-28
Technical Paper
2017-01-0544
Philipp Mayr, Gerhard Pirker, Andreas Wimmer, Markus Krenn
Abstract It is critical for gas and dual fuel engines to have improved transient characteristics in order that they can successfully compete with diesel engines. Testing of transient behavior as well as of different control strategies for the multi-cylinder engine (MCE) should already be done on the single cylinder engine (SCE) test bed during the development process. This paper presents tools and algorithms that simulate transient MCE behavior on a SCE test bed. A methodology that includes both simulation and measurements is developed for a large two-stage turbocharged gas engine. Simple and fast models and algorithms are created that are able to provide the boundary conditions (e.g., boost pressure and exhaust back pressure) of a multi-cylinder engine in transient operation in real-time for use on the SCE test bed. The main models of the methodology are discussed in detail.
2017-03-28
Technical Paper
2017-01-0543
Oliver Hofmann, Shijin Han, Daniel Rixen
Abstract This study discusses model-based injection rate estimation in common rail diesel injectors exhibiting aging phenomena. Since they result in unexpected injection behavior, aging effects like coking or cavitation may impair combustion performance, which justifies the need for new modeling and estimation approaches. To predict injection characteristics, a simulation model for the bottom section of the injector is introduced, with a main focus on modeling the hydraulic components. Using rail pressure and control piston lift as inputs, a reduced model is then derived in state-space representation, which may be used for the application of an observer in hardware-in-the-loop (HIL) environments. Both models are compared and validated with experimental data, with which they show good agreement. Aging effects and nozzle wear, which result in model uncertainties, are considered using a fault model in combination with an extended Kalman filter (EKF) observer scheme.
2017-03-28
Technical Paper
2017-01-0539
Duc-Khanh Nguyen, Sebastian Verhelst
Abstract Methanol fueled spark ignition (SI) engines have the potential for very high efficiency using an advanced heat recovery system for fuel reforming. In order to allow simulation of such an engine system, several sub-models are needed. This paper reports the development of two laminar burning velocity correlations, corresponding to two reforming concepts, one in which the reformer uses water from an extra tank to produce hydrogen rich gas (syngas) and another that employs the water vapor in the exhaust gas recirculation (EGR) stream to produce reformed-EGR (R-EGR). This work uses a one-dimensional (1D) flame simulation tool with a comprehensive chemical kinetic mechanism to predict the laminar burning velocities of methanol/syngas blends and correlate it. The syngas is a mixture of H2/CO/CO2 with a CO selectivity of 6.5% to simulate the methanol steam reforming products over a Cu-Mn/Al catalyst.
2017-03-28
Technical Paper
2017-01-0537
Murat Ates, Ronald D. Matthews, Matthew J. Hall
Abstract A quasi-dimensional model for a direct injection diesel engine was developed based on experiments at Sandia National Laboratory. The Sandia researchers obtained images describing diesel spray evolution, spray mixing, premixed combustion, mixing controlled combustion, soot formation, and NOx formation. Dec [1] combined all of the available images to develop a conceptual diesel combustion model to describe diesel combustion from the start of injection up to the quasi-steady form of the jet. The end of injection behavior was left undescribed in this conceptual model because no clear image was available due to the chaotic behavior of diesel combustion. A conceptual end-of-injection diesel combustion behavior model was developed to capture diesel combustion throughout its life span. The compression, expansion, and gas exchange stages are modeled via zero-dimensional single zone calculations.
2017-03-28
Technical Paper
2017-01-0558
Lei Cui, Tianyou Wang, Kai Sun, Zhen Lu, Zhizhao Che, Yanzhe Sun
Abstract The scavenging process in two-stroke marine engines not only transports burnt gas out of the cylinder but also provides fresh air for the next cycle, thereby significantly affecting the engine performance. In order to enhance fuel-air mixing, the scavenging process usually generates swirling flow in uniflow-type scavenging engines. The scavenging stability directly determines the scavenging efficiency and even influences fuel-air mixing, combustion, and emission of the engine. In the present study, a computational fluid dynamics (CFD) analysis of the scavenging process in a steady-state scavenging flow test is conducted. A precession phenomenon is found in the high swirl model, and Proper Orthogonal Decomposition (POD) method is used to analyze the reason and the multi-scale characteristics of the precession phenomenon.
2017-03-28
Technical Paper
2017-01-0553
Lorenzo Sforza, Tommaso Lucchini, Angelo Onorati, Xiucheng Zhu, Seong-Young Lee
Abstract Objective of this work is the incorporation of the flame stretch effects in an Eulerian-Lagrangian model for premixed SI combustion in order to describe ignition and flame propagation under highly inhomogeneous flow conditions. To this end, effects of energy transfer from electrical circuit and turbulent flame propagation were fully decoupled. The first ones are taken into account by Lagrangian particles whose main purpose is to generate an initial burned field in the computational domain. Turbulent flame development is instead considered only in the Eulerian gas phase for a better description of the local flow effects. To improve the model predictive capabilities, flame stretch effects were introduced in the turbulent combustion model by using formulations coming from the asymptotic theory and recently verified by means of DNS studies. Experiments carried out at Michigan Tech University in a pressurized, constant-volume vessel were used to validate the proposed approach.
2017-03-28
Technical Paper
2017-01-0547
Zvonimir Petranovic, Wilfried Edelbauer, Milan Vujanović, Peter Priesching, Reinhard Tatschl, Neven Duić
Abstract Commonly, the spray process in Direct Injection (DI) diesel engines is modeled with the Euler Lagrangian discrete droplet approach which has limited validity in the dense spray region, close to the injector nozzle hole exit. In the presented research, a new reactive spray modelling method has been developed and used within the 3D RANS CFD framework. The spray process was modelled with the Euler Eulerian multiphase approach, extended to the size-of-classes approach which ensures reliable interphase momentum transfer description. In this approach, both the gas and the discrete phase are considered as continuum, and divided into classes according to the ascending droplet diameter. The combustion process was modelled by taking into account chemical kinetics and by solving general gas phase reaction equations.
2017-03-28
Technical Paper
2017-01-0548
Taehoon Kim, Sungwook Park
Abstract An important challenge for modeling Direct-Injection Spark-Ignition (DISI) gasoline engines is understanding flash boiling spray. Flash boiling occurs when the ambient pressure is lower than the vapor pressure of the fuel and affects the spray structure and mixture formation process inside an engine. Gasoline is a multi-component fuel and the effects of each component on flash boiling are difficult to estimate. As a preliminary study to investigate the mixture formation process of the flash boiling spray, a single-component fuel was used to validate the flash breakup model. The flash breakup model was applied to KIVA 3V release2. Bubble growth in the drop was modelled by the Rayleigh-Plesset equation. When bubbles grow to satisfy the breakup criterion, breakup occurs and induces a smaller SMD for flash breakup cases. To investigate flash breakup modeling, simulations without the flash breakup model and with the flash breakup model was compared.
2017-03-28
Technical Paper
2017-01-0571
Tim Lackmann, Tommaso Lucchini, Gianluca D'Errico, Alan Kerstein, Michael Oevermann
Abstract Many new combustion concepts are currently being investigated to further improve engines in terms of both efficiency and emissions. Examples include homogeneous charge compression ignition (HCCI), lean stratified premixed combustion, stratified charge compression ignition (SCCI), and high levels of exhaust gas recirculation (EGR) in diesel engines, known as low temperature combustion (LTC). All of these combustion concepts have in common that the temperatures are lower than in traditional spark ignition or diesel engines. To further improve and develop combustion concepts for clean and highly efficient engines, it is necessary to develop new computational tools that can be used to describe and optimize processes in nonstandard conditions, such as low temperature combustion.
2017-03-28
Technical Paper
2017-01-0574
Ishan Verma, Ellen Meeks, Eric Bish, Martin Kuntz, Karthik Puduppakkam, Long Liang, Chitralkumar Naik
Abstract Emissions from Diesel engines have been a major concern for many years, particularly with regards to the impact of NOx and particulate matter on human health. Exhaust gas re-circulation (EGR) is a widely used method in diesel engines for controlling NOx production. While EGR rates can be varied to ensure engine performance and reduce NOx emissions, EGR also influences the ignition delay, reduces the peak combustion temperature and increases particulate emissions. Moreover, the injection timing directly affects NOx and particulate emissions under the broad and highly variable operating conditions. An effective CFD-based design tool for diesel engines must therefore include robust and accurate predictive capabilities for combustion and pollutant formation, to address the complex design tradeoffs. The objective of the present study is to evaluate CFD modeling of diesel engine combustion and emissions for various combinations of EGR rates and injection timings.
2017-03-28
Technical Paper
2017-01-0579
Stephane Chevillard, Olivier Colin, Julien Bohbot, Mingjie Wang, Eric Pomraning, P. K. Senecal
Abstract Nowadays Spark Ignition (SI) engine developments focus on downsizing, in order to increase the engine load level and consequently its efficiency. As a side effect, knock occurrence is strongly increased. The current strategy to avoid knock is to reduce the spark advance which limits the potential of downsizing in terms of consumption reduction. Reducing the engine propensity to knock is therefore a first order subject for car manufacturers. Engineers need competitive tools to tackle such a complex phenomenon. In this paper the 3D RANS simulations ability to satisfactorily represent knock tendencies is demonstrated. ECFM (Extended Coherent Flame Model) has been recently implemented by IFPEN in CONVERGE and coupled with TKI (Tabulated Kinetics Ignition) to represent Auto-Ignition in SI engine. These models have been applied on a single cylinder engine configuration dedicated to abnormal combustion study.
2017-03-28
Technical Paper
2017-01-0577
Bersan Akkurt, Hayri Yigit Akargun, L. M. T. Somers, N. G. Deen, Ricardo Novella, Eduardo Javier Pérez-Sánchez
Abstract Advanced Computational Fluid Dynamics (CFD) modeling of reacting sprays provides access to information not available even applying the most advanced experimental techniques. This is particularly evident if the combustion model handles detailed chemical kinetic models efficiently to describe the fuel auto-ignition and oxidation processes. Complex chemistry also provides the temporal evolution of key species closely related to emissions formation, such as polycyclic aromatic hydrocarbons (PAHs) that are well-known as soot precursors. In this framework, present investigation focuses on the analysis of the so-called Spray-A combustion characteristics using two different flamelet-based combustion models. Both Reynolds-Averaged Navier-Stokes (RANS) and Large-Eddy Simulation (LES) predictions are combined to study not only the averaged spray characteristics, but also the relevance of different realizations in this particular problem.
2017-03-28
Technical Paper
2017-01-0582
Naoki Kurimoto, Naoki Watanabe, Shinya Hoshi, Satoru Sasaki, Masashi Matsumoto
Abstract A methodology for simulating effect of international variations in fuel compositions on spray combustion is proposed. The methodology is validated with spray combustion experiments with real fuels from three different countries. The compositions of those fuels were analyzed through GC×GC and H-NMR. It was found that ignition delay times, flame region and flame luminosity were significantly affected by the compositional variations. For the simulation, an evaporation surrogate consisting of twenty two species, covering basic molecular types and a wide range of carbon numbers, is developed. Each species in the evaporation surrogate is then virtually converted to a reaction surrogate consisting of n-hexadecane, methylcyclohexane and 1,2,4-trimethyl benzene so that combustion reactions can be calculated with a published kinetic model. The virtual species conversion (VSC) is made so as to take over combustion-related properties of each species of evaporation surrogates.
2017-03-28
Technical Paper
2017-01-0560
Mateusz Pucilowski, Mehdi Jangi, Sam Shamun, Changle Li, Martin Tuner, Xue-Song Bai
Abstract Methanol as an alternative fuel in internal combustion engines has an advantage in decreasing emissions of greenhouse gases and soot. Hence, developing of a high performance internal combustion engine operating with methanol has attracted the attention in industry and academic research community. This paper presents a numerical study of methanol combustion at different start-of-injection (SOI) in a direct injection compression ignition (DICI) engine supported by experimental studies. The aim is to investigate the combustion behavior of methanol with single and double injection at close to top-dead-center (TDC) conditions. The experimental engine is a modified version of a heavy duty D13 Scania engine. URANS simulations are performed for various injection timings with delayed SOI towards TDC, aiming at analyzing the characteristics of partially premixed combustion (PPC).
2017-03-28
Technical Paper
2017-01-0559
Lucas Eder, Constantin Kiesling, Peter Priesching, Gerhard Pirker, Andreas Wimmer
Abstract Using natural gas as a fuel in internal combustion engines is a promising way to obtain efficient power generation with relatively low environmental impact. Dual fuel operation is especially interesting because it can combine the safety and reliability of the basic diesel concept with fuel flexibility. To deal with the greater number of degrees of freedom caused by the interaction of two fuels and combining different combustion regimes, it is imperative to use simulation methods in the development process to gain a better understanding of the combustion behavior. This paper presents current research into ignition and combustion of a premixed natural gas/air charge with a diesel pilot spray in a large bore diesel ignited gas engine with a focus on 3D-CFD simulation. Special attention was paid to injection and combustion. The highly transient behavior of the diesel injector especially at small injection quantities poses challenges to the numerical simulation of the spray.
2017-03-28
Technical Paper
2017-01-0561
Federico Perini, Kan Zha, Stephen Busch, Rolf Reitz
Abstract In this work, linear, non-linear and a generalized renormalization group (RNG) two-equation RANS turbulence models of the k-epsilon form were compared for the prediction of turbulent compressible flows in diesel engines. The object-oriented, multidimensional parallel code FRESCO, developed at the University of Wisconsin, was used to test the alternative models versus the standard k-epsilon model. Test cases featured the academic backward facing step and the impinging gas jet in a quiescent chamber. Diesel engine flows featured high-pressure spray injection in a constant volume vessel from the Engine Combustion Network (ECN), as well as intake flows in a high-swirl diesel engine. For the engine intake flows, a model of the Sandia National Laboratories 1.9L light-duty single cylinder optical engine was used.
2017-03-28
Technical Paper
2017-01-0564
Prithwish Kundu, Muhsin Ameen, Umesh Unnikrishnan, Sibendu Som
Abstract Modeling unsteady turbulent flame development in lifted spray flames is important as a strong correlation exists between pollutant formation and the transient flame features such as auto-ignition, flame propagation and flame stabilization. Detailed chemistry mechanisms with large number of species are required to resolve the chemical kinetics accurately. These factors make high-fidelity simulation of engine combustion computationally expensive. In this work, a turbulent combustion model is proposed based on tabulation of flamelets. The aim is to develop a comprehensive combustion modeling approach incorporating detailed chemistry mechanisms, turbulence models and highly resolved grids leveraging the computational cost advantage of tabulation. A novel technique of implementing unsteady flamelet libraries without the use of progress variables is implemented for igniting sprays called Tabulated Flamelet Model (TFM).
2017-03-28
Technical Paper
2017-01-0567
Andrea Twellmeyer, Fabian Kopple, Bernhard Weigand
Abstract Compressed Natural Gas (CNG) is a promising alternative fuel for internal combustion engines as its combustion is fuel-efficient and lean in carbon dioxide compared to gasoline. The high octane number of methane gives rise to significant increase of the thermodynamic efficiency due to higher possible compression ratios. In order to use this potential, new stratified mixture formation concepts for CNG are investigated by means of numerical fluid simulations. For decades RANS methods have been the industry standard to model three-dimensional flows. Indeed, there are well-known deficiencies of the widely used eddy viscosity turbulence models based on the applied Boussinesq hypothesis. Reynolds stress turbulence models as well as scale resolving simulation approaches can be appealing alternative choices since they offer higher accuracy. However, due to their large computing effort, they are still mostly impractical for the daily use in industrial product development processes.
2017-03-28
Technical Paper
2017-01-0565
Ji Yu, Motoyuki Abe, Yoshihiro Sukegawa
Abstract We developed a numerical method for PFI engine, which would take complex intake-port phenomena into consideration. Numerical study for PFI engine has additional difficulty compared with that for GDI engine, because in-cylinder distribution of mixture is strongly affected by remaining fuel in intake-port. The new simulation method proposed in this paper has adopted split calculation of two steps. Fuel distribution in intake-port is calculated in the first step, and then this result of adhered and floating fuel distribution in intake-port is used as boundary and initial conditions in the next step. Together these two steps realize accurate in-cylinder mixture distribution prediction. According to experimental verification, the new method showed a capability to predict accurate liquid film distribution with less calculation cost. And then we applied the method into the investigation for optimum injection strategy to improve engine performance and to reduce emission.
2017-03-28
Technical Paper
2017-01-0568
Valentina Fraioli, Carlo Beatrice, Gabriele Di Blasio, Giacomo Belgiorno, Marianna Migliaccio
Abstract The adoption of gaseous fuels for Light Duty (LD) engines is considered a promising solution to efficiently reduce greenhouse gases emissions and diversify fuels supplies, while keeping pollutants production within the limits. In this respect, the Dual Fuel (DF) concept has already proven to be, generally speaking, a viable solution, industrially implemented for several applications in the Heavy-Duty (HD) engines category. Despite this, some issues still require a technological solution, preventing the commercialization of DF engines in wider automotive fields, including the release of high amounts of unburned species, possibility of engine knock, chance of thermal efficiency reduction. In this framework, numerical simulation can be a useful tool, not only to better understand specific characteristics of DF combustion, but also to explore specific geometrical modifications and engine calibrations capable to adapt current LD architectures to this concept.
2017-03-28
Technical Paper
2017-01-0626
LeeAnn Wang, George Garfinkel, Ahteram Khan, Mayur Harsha, Prashanth Rao
Abstract When a driver completes an aggressive drive cycle on a hybrid vehicle, the High Voltage (HV) battery system may be at risk of exceeding the power limit temperature, due to continuous absorption of radiative and convective heat from the environment, such as from exhaust and pavement, even after key-off. In such a case, in the absence of active cooling, the vehicle may not be keyed-on until battery temperatures are reduced below critical values. A transient thermal analysis is conducted on a HV battery system to simulate the key-off operation using an effective Computational Fluid Dynamics (CFD) methodology. Two stages are considered in this methodology to capture the complexity of the geometry and the multiple phenomena that need to be simulated in the model. The introduced modeling technique can be used for Full Hybrid Electric Vehicle (FHEV) and Plug-in Hybrid Electric Vehicle (PHEV) transient key-off situations.
2017-03-28
Technical Paper
2017-01-0623
Zun Wang, Yi Zhang, Christophe lenormand, Mohammed Ansari, Manuel Henner
Abstract Radiator thermal cycle test is a test method to check out the robustness of a radiator. During the test, the radiator is going through transient cycles that include high and low temperature spikes. These spikes could lead to component failure and transient temperature map is the key to predict high thermal strain and failure locations. In this investigation, an accurate and efficient way of building a numerical model to simulate the transient thermal performance of the radiator is introduced. A good correlation with physical test result is observed on temperature values at various locations.
2017-03-28
Technical Paper
2017-01-0640
Robert Wade, Steven Murphy, Paul Cross, Craig Hansen
Abstract The Variable Displacement Supercharger (VDS) is a twin helical screw style compressor that has a feature to change its displacement and its compression ratio actively during vehicle operation. This device can reduce the parasitic losses associated with supercharging and improve the relative fuel economy of a supercharged engine. Supercharging is a boosting choice with several advantages over turbocharging. There is fast pressure delivery to the engine intake manifold for fast engine torque response providing the fun to drive feel. The performance delivered by a supercharger can enable engine fuel economy actions to include engine downsizing and downspeeding. The cost and difficulty of engineering hot exhaust components is eliminated when using only an air side compressor. Faster catalyst warm up can be achieved when not warming the turbine housing of a turbocharger.
2017-03-28
Technical Paper
2017-01-0702
Raouf Mobasheri, Mahdi Seddiq
Abstract The simultaneous effects of pilot fuel quantity and pilot injection timing on engine performance and amount of pollutant emission have been computationally investigated in a High Speed Direct Injection (HSDI) diesel engine. In this study, a modified parameter called “Homogeneity Factor of in-cylinder charge (HF)” has been applied to analyze the air-fuel mixing and combustion processes. For this purpose, the simulated results has been firstly compared with the experimental data and a good agreement has been achieved for simulating the in-cylinder pressure and the amount of pollutant emissions. Then, nine different strategies based on two variables (the amount of fuel mass in pilot and main injection as well as the dwell between two injections) have been investigated.
2017-03-28
Technical Paper
2017-01-0713
Håkan Persson, Aristotelis Babajimopoulos, Arjan Helmantel, Fredrik Holst, Elin Stenmark
Abstract The demands for a future diesel engine in terms of emission compliance, CO2 emissions, performance and cost effectiveness set new requirements for the development process of the combustion system. This paper focuses on the development of the next generation Volvo Cars diesel combustion system, which should comply with Euro 6d including Real Driving Emissions (RDE), with emphasis on the novel methods applied throughout the process. The foundation of a high performing combustion system is formed by first determining the requirements for the system, after which the key factors that affect system performance are selected, such as the charge motion, combustion chamber geometry and injector nozzle geometry. Based on the requirements, a robust charge motion with desired flow characteristics is defined. A new automated CFD optimization process for combustion chamber geometry and spray target is developed.
Viewing 181 to 210 of 33097