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2017-06-05
Technical Paper
2017-01-1808
Francis Nardella
In a previous report, it was shown that power transmission through the camshaft reduced the first mode natural frequency of the powertrain and translated its convergence with dominant engine excitatory harmonics to a lower engine speed resulting in a marked reduction in torsional vibration for geared 6 cylinder compression ignition engines for aviation. This report describes a sweep though 2 and 4 stroke engines with differing numbers of cylinders configured as standard gear reduction (SGRE) and with power transmission through the camshaft (CDSE). Four and 6 cylinder engines were modeled as opposed boxer engines and 8, 10 and 12 cylinder engines were modeled as 180-degree V-engines. Mass-elastic models of the different engine power train configurations were modeled using the torsional vibration module in Shaft Designer obtained from SKF (Svenska Kullagerfabriken). Crankshaft, camshaft, gearing, pistons, piston pins and connecting rods with bolts were modeled in Solidworks.
2017-06-05
Technical Paper
2017-01-1802
Dong chul Lee, Insoo Jung, Jaemin Jin, Stephan Brandl, Mehdi Mehrgou
Classical approaches to development require a lot of time and cost to make samples involved the major design factors, which is why there have been recent researches to improve the efficiency of the development through a variety of simulation techniques. NVH simulation is of importance in this advanced phase, the design of all the parts should be satisfactory from the NVH point of view during the first phase of the project. This paper presents such an approach of simulation for the prediction radiated noise from a diesel engine with integrated powertrain model with changing combustion excitation. For changing combustion excitation, the cylinder pressure is measured and used as an input for simulation. The simulation model is validated with comparing the result of experiment in specified frequency ranges that the level of the noise is made louder than the development target.
2017-06-05
Technical Paper
2017-01-1809
Dhanesh Purekar
Engine noise is considered significant aspect of product quality for light and medium duty diesel engine market applications. Gear whine is one of those noise issues which is considered objectionable and impacts the customer perception. Gear whine could results due to defects in the gear manufacturing process and/or due to inaccurate design of the gear macro and micro-geometry. The focus of this technical paper is to discuss gear whine considerations from the production plant perspective. A gear whine case study is presented on the data collected on one of the Cummins diesel engines in the production environment. This paper also includes quick overview of measurement process, test cell environment, noise acceptance criteria considerations. This paper highlights the benefits of using production facility for developing next generation of product development from whine perspective.
2017-06-05
Technical Paper
2017-01-1871
Nobutaka Tsujiuchi, Masahiro Akei, Akihito Ito, Daisuke Kubota, Koichi Osamura
This paper describes new method for selecting optimal field points in Inverse-Numerical Acoustic analysis (INA), and an application to construction of sound source model for diesel engine. INA is a method that identifies surface vibration of the sound source by using acoustic transfer functions and actual sound pressures which are measured at field points located near the sound source. In the INA, for measuring sound pressures, it is necessary to determine the arrangement of field points. The increase of field points leads to longer test and analysis time. Therefore, guidelines for deciding field point arrangement are needed to conduct INA efficiently. The authors focused on the standard deviations of distance between sound source elements and field points, and proposed new guideline for optimal selection of the field points, in a past study. In the past study, the effectiveness of this guideline was verified using a simple plate model.
2017-06-05
Technical Paper
2017-01-1874
Tongyang Shi, Yangfan Liu, J Stuart Bolton, Frank Eberhardt, Warner Frazer
Wideband Acoustical Holography, which is a monopole-based equivalent source procedure (J. Hald, “Wideband Acoustical Holography”, INTER-NOISE 2014), have been proven to offer an accurate noise source holography result in experiments with a simple noise source: e..g., a loudspeaker (T. Shi, Y. Liu, J. Bolton, ”The Use of Wideband Holography for Noise Source Visualization”, NOISE-CON 2016). From a previous study, it was found that the advantage of this procedure is the ability to optimize the solution in the case of an under-determined system: i.e., when the number of measurements is less than the number of parameters that must be estimated in the model. In the present work, a diesel engine noise source was measured by using one set of measurements from a thirty six channel irregular array placed in front of the diesel engine.
2017-06-05
Technical Paper
2017-01-1811
Jouji Kimura, Tatsuya Tanaka, Kenjiro Hakomoto, Kousuke Kawase, Shinichiro Kobayashi
This paper describes based on the mechanism of whirl resonance about the characteristic of serious bending stress which occurred in the crankshaft rear. The following steps to prove that the bending stress is caused by whirl resonance of the crankshaft rear end. At first, the authors showed that the resonance frequency of bending stress for forward whirl which takes place in the same direction as crankshaft rotation increases with the increasing engine speed, and the resonance frequency of bending stress for reverse whirl which takes place in the reverse direction as crankshaft rotation decreases with the increasing engine speed. Secondly, it was found out that there are two groups, the correlation between the resonance frequency and the resonance engine speed of the measured bending stresses in the crankshaft rear. One is the group that the resonance frequency increases with the increasing engine speed.
2017-06-05
Technical Paper
2017-01-1810
Shinichiro Kobayashi, Kenjiro Hakomoto, Kousuke Kawase, Makoto Kidokoro, Jouji Kimura
This paper describes the characteristic and the mechanism of serious bending stress occurred in the crankshaft rear at the whirl occurred. At first, the order tracking analysis is used for the measured bending stress. Then, many different resonances of the frequency and the amplitude occurred, and the curve of each order around resonance engine speed was unique, for example sharply peak, flat peak, and peak of 2 steps. Secondly, this paper described that the resonance frequency of bending stress for forward whirl which occurs in the same direction as crankshaft rotation and for reverse whirl which occurs in the reverse direction as crankshaft rotation increases and decreases with the increasing engine speed. It showed that the whirl occurred in the crankshaft rear-end, as the resonance frequency of measurement result increases and decreases linearly with the increasing engine speed.
2017-05-18
Journal Article
2017-01-9375
Lukas Moeltner, Lucas Konstantinoff, Verena Schallhart
Abstract The increasingly stringent emission legislation worldwide and the demand for independence from fossil energy carriers represent major challenges for the future development of diesel engines, particularly for maintaining the diesel engine’s positive characteristics, such as its dynamic driving performance and fuel economy, while drastically reducing emissions. This survey investigates alternative fuel blends used in a state-of-the-art EURO 6 diesel engine with different shares of biomass to liquid, hydrotreated vegetable oils and fatty acid methyl ester, which present a possibility to meet these requirements. In particular, the reduction of particulate matter and, as a result, the possibility to reduce nitrogen oxides emissions holds remarkable potential for the application of synthetic fuels in diesel engines. The investigated fuel blends generally demonstrate good applicability when used in the test engine with standard settings.
2017-04-19
Technical Paper
2017-01-5000
Alexander Koder, Florian Zacherl, Hans-Peter Rabl, Wolfgang Mayer, Georg Gruber, Thomas Dotzer
Abstract An effective way to reduce greenhouse gas emissions (GHGs) is to use rurally produced straight jatropha oil as a substitute for diesel fuel. However, the different physical and chemical properties of straight vegetable oils (SVOs) require a customized setup of the combustion engine, particularly of the injection timing and quantity. Therefore, this study demonstrates the differences in the injection and combustion processes of jatropha oil compared to diesel fuel, particularly in terms of its compatibility with exhaust gas recirculation (EGR). A 2.2 l common-rail diesel engine with a two-stage turbocharging concept was used for testing. To examine the differences in injection rate shaping of diesel fuel and jatropha oil, the injector was tested with an injection rate analyzer using both the fuels. To investigate the combustion process, the engine was mounted at an engine test bench and equipped with a cylinder pressure indication system.
2017-03-28
Technical Paper
2017-01-1292
Saiful Bari, Idris Saad
Abstract Diesel engine can be run with biodiesel which has the potential to supplement the receding supply of crude oil. As biodiesel possess similar physiochemical properties to diesel, most diesel engines can run with biodiesel with minimum modifications. However, the viscosity of biodiesel is higher, and the calorific value is lower than diesel. Therefore, when biodiesel is used in diesel engines, it is usually blended with diesel at different proportions. Use of 100% biodiesel in diesel engines shows inferior performance of having lower power and torque. Improving in-cylinder airflow characteristic to break down higher viscous biodiesel and to improve air-fuel mixing are the aims of this research. Therefore, guide vanes in the intake runner were used in this research to improve the performance of diesel engine run with biodiesel.
2017-03-28
Technical Paper
2017-01-0876
Senthil Kumar Masimalai, Jai Kumar Mayakrishnan
Abstract Different methods to improve the performance of a WCO (waste cooking oil of sunflower) based mono cylinder compression ignition (CI) engine were investigated. Initially WCO was converted into its emulsion by emulsification process and tested as fuel. In the second phase, the engine intake system was modified to admit excess oxygen along with air to test the engine with WCO and WCO emulsion as fuels under oxygen enriched environment. In the third phase, the engine was modified to work in the dual fuel mode with hydrogen being used as the inducted fuel and either WCO or WCO emulsion used as the pilot fuel. All the tests were carried out at 100% and 40% of the maximum load (3.7 kW power output) at the rated speed of 1500 rpm. Engine data with neat diesel and neat WCO were used for comparison. WCO emulsion indicated considerable improvement in performance. The smoke and NOx values were noted to be less than neat WCO.
2017-03-28
Technical Paper
2017-01-0873
Senthilkumar Masimalai, Jai Kumar Mayakrishnan, Natraj Ganesan
Abstract This paper presents a comprehensive study on using MO (Mahua oil) as fuel effectively in a diesel engine by adopting emulsification and TBC (Thermal Barrier Coating) techniques. A mono cylinder diesel engine was used for the study. Initially trials were made on the engine using neat diesel (ND), Neat Mahua oil (NMO) as fuels. In the second phase, NMO was converted into its stable emulsion (called as MOE) and tested in the engine. Finally thermal barrier coating of 0.2 mm was made on the piston, valves and cylinder head of the engine using the ceramic power of Al2O3 and the engine was tested using NMO and MOE as fuels in the TBC engine. Results indicated improvement in BTE (brake thermal efficiency) with MOE as compared to NMO mainly at high power outputs in the unmodified engine. The maximum BTE was found as 31.5% with ND, 27.2% with NMO and 30.4% with MOE at the peak power output.
2017-03-28
Technical Paper
2017-01-0875
Valentin Soloiu, Jose Moncada, Martin Muinos, Aliyah Knowles, Remi Gaubert, Thomas Beyerl, Gustavo Molina
Abstract This paper investigates the performance of an indirect injection (IDI) diesel engine fueled with Bu25, 75% ultra-low sulfur diesel (ULSD#2) blended with 25% n-butanol by mass. N-butanol, derivable from biomass feedstock, was used given its availability as an alternative fuel that can supplement the existing limited fossil fuel supply. Combustion and emissions were investigated at 2000 rpm across loads of 4.3-7.2 bar indicated mean effective pressure (IMEP). Cylinder pressure was collected using Kistler piezoelectric transducers in the precombustion (PC) and main combustion (MC) chambers. Ignition delays ranged from 0.74 - 1.02 ms for both operated fuels. Even though n-butanol has a lower cetane number, the high swirl in the separate combustion chamber would help advance its premixed combustion. The heat release rate of Bu25 became initially 3 J/crank-angle-degree (CAD) higher than that of ULSD#2 as load increased to 7.2 bar IMEP.
2017-03-28
Technical Paper
2017-01-0869
Job Immanuel Encarnacion, Edwin Quiros
Abstract The Philippine Biofuels Act of 2006 (RA 9367) requires commercial diesel fuel to be mixed with Coconut Methyl Ester (CME) in accordance with the Philippine Clean Air Act of 1999 (RA 8749). As of 2015, the blend percentage is at 2% CME v/v, contrary to the scheduled 5% as stipulated in the biofuels act. Researches done locally showing the performance and emissions of CME-fueled engines are few and thus the basis for the CME percentage increase is still questionable and hampers the drive for the further implementation of the policy. The study investigates the influence of varying percentages of CME blends (2%, 5%, 10%, 15%, 20% v/v) to the performance and emissions of a heavy-duty turbocharged common rail direct injection (CRDI) engine. The engine is run at steady state at partial load (50Nm and 250 Nm) and at near full load (500Nm). Each run is set at three pedal positions, α (25%, 50% and 60%), controlled directly from the engine control unit.
2017-03-28
Technical Paper
2017-01-0870
Yuanxu Li, Xiangyu Meng, Karthik Nithyanandan, Chia-Fon Lee, Zhi Ning
Abstract Due to the increasing consumption of fossil fuels, alternative fuels in internal combustion engines have attracted a lot of attention in recent years. Ethanol is the most common alternative fuel used in spark ignition (SI) engines due to its advantages of biodegradability, positively impacting emissions reduction as well as octane number improvement. Meanwhile, acetone is well-known as one of the industrial waste solvents for synthetic fibers and most plastic materials. In comparison to ethanol, acetone has a number of more desirable properties for being a viable alternative fuel such as its higher energy density, heating value and volatility.
2017-03-28
Technical Paper
2017-01-0573
Mohammed Jaasim Mubarak ali, Francisco Hernandez Perez, R Vallinayagam, S Vedharaj, Bengt Johansson, Hong Im
Abstract Full cycle simulations of KAUST optical diesel engine were conducted in order to provide insights into the details of fuel spray, mixing, and combustion characteristics at different start of injection (SOI) conditions. Although optical diagnostics provide valuable information, the high fidelity simulations with matched parametric conditions improve fundamental understanding of relevant physical and chemical processes by accessing additional observables such as the local mixture distribution, intermediate species concentrations, and detailed chemical reaction rates. Commercial software, CONVERGE™, was used as the main simulation tool, with the Reynolds averaged Navier-Stokes (RANS) turbulence model and the multi-zone (SAGE) combustion model to compute the chemical reaction terms. SOI is varied from late compression ignition (CI) to early partially premixed combustion (PPC) conditions.
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
2017-01-0627
Bo Yang, Peter Woyciesjes, Aleksei Gershun
Abstract In this paper, new test results in the use of electrochemical techniques to measure corrosion in extended life engine coolants are presented. Corrosion protection performance of the engine coolants (including both fresh coolants and simulated used coolants) for typical cooling system metals under heat rejecting and heat accepting surface corrosion conditions for both general corrosion and localized corrosion are measured under conditions similar to the ones encountered in vehicle engine cooling systems as a function of immersion time. Fleet tests of the coolants were also conducted. They are used to provide support on the electrochemical test methodologies adopted. The effective use of electrochemical techniques to aid the development of the next generation of extended life coolant technologies with improved corrosion protection performance and a longer service life will be demonstrated and discussed.
2017-03-28
Technical Paper
2017-01-0629
John Kuo, George Garfinkel
Abstract Thermal modeling of liquid-cooled vehicle traction battery assemblies using Computational Fluid Dynamics (CFD) usually involves large models to accurately resolve small cooling channel details, and intensive computation to simulate drive-cycle transient solutions. This paper proposes a segregated method to divide the system into three parts: the cells, the cold plate and the interface between them. Each of the three parts can be separated and thermally characterized and then combined to predict the overall system thermal behavior for both steady-state and transient operating conditions. The method largely simplifies battery thermal analysis to overcome the limitations of using large 3D CFD models especially for pack level dynamic drive cycle simulations.
2017-03-28
Technical Paper
2017-01-0637
Yan Zhang, Ziyu Wang, Honglin Bai, Chao Guo, Jinlong liu, Yufeng Li
Abstract Mechanical load and thermal load are the two main barriers limiting the engine power output of heavy duty (HD) diesel engines. Usually, the peak cylinder pressure could be reduced by retarding combustion phasing while introducing the drawback of higher thermal load and exhaust temperature. In this paper, Miller cycle with late intake valve closing was investigated at high speed high load condition (77 kW/L) on a single cylinder HD diesel engine. The results showed the simultaneous reduction of mechanical and thermal loads. In the meanwhile, higher boosting pressure was required to compensate the Miller loss of the intake charge during intake and compression process. The combustion temperature, cylinder pressure, exhaust temperature and NOx emission were reduced significantly with Miller cycle at the operating condition. Furthermore, the combustion process, smoke number and fuel consumption were analysed.
2017-03-28
Technical Paper
2017-01-0516
Tim Franken, Arnd Sommerhoff, Werner Willems, Andrea Matrisciano, Harry Lehtiniemi, Anders Borg, Corinna Netzer, Fabian Mauss
Today numerical models are a major part of the diesel engine development. They are applied during several stages of the development process to perform extensive parameter studies and to investigate flow and combustion phenomena in detail. The models are divided by complexity and computational costs since one has to decide what the best choice for the task is. 0D models are suitable for problems with large parameter spaces and multiple operating points, e.g. engine map simulation and parameter sweeps. Therefore, it is necessary to incorporate physical models to improve the predictive capability of these models. This work focuses on turbulence and mixing modeling within a 0D direct injection stochastic reactor model. The model is based on a probability density function approach and incorporates submodels for direct fuel injection, vaporization, heat transfer, turbulent mixing and detailed chemistry.
2017-03-28
Technical Paper
2017-01-0512
Andrea Matrisciano, Tim Franken, Cathleen Perlman, Anders Borg, Harry Lehtiniemi, Fabian Mauss
Abstract A novel 0-D Probability Density Function (PDF) based approach for the modelling of Diesel combustion using tabulated chemistry is presented. The Direct Injection Stochastic Reactor Model (DI-SRM) by Pasternak et al. has been extended with a progress variable based framework allowing the use of a pre-calculated auto-ignition table. Auto-ignition is tabulated through adiabatic constant pressure reactor calculations. The tabulated chemistry based implementation has been assessed against the previously presented DI-SRM version by Pasternak et al. where chemical reactions are solved online. The chemical mechanism used in this work for both, online chemistry run and table generation, is an extended version of the scheme presented by Nawdial et al. The main fuel species are n-decane, α-methylnaphthalene and methyl-decanoate giving a size of 463 species and 7600 reactions.
2017-03-28
Technical Paper
2017-01-0136
Apostolos Karvountzis-Kontakiotis, Apostolos Pesiridis, Hua Zhao, Fuhaid Alshammari, Benjamin Franchetti, Ioannis Pesmazoglou, Lorenzo Tocci
Abstract Modern heavy duty diesel engines can well extend the goal of 50% brake thermal efficiency by utilizing waste heat recovery (WHR) technologies. The effect of an ORC WHR system on engine brake specific fuel consumption (bsfc) is a compromise between the fuel penalty due to the higher exhaust backpressure and the additional power from the WHR system that is not attributed to fuel consumption. This work focuses on the fuel efficiency benefits of installing an ORC WHR system on a heavy duty diesel engine. A six cylinder, 7.25ℓ heavy duty diesel engine is employed to experimentally explore the effect of backpressure on fuel consumption. A zero-dimensional, detailed physical ORC model is utilized to predict ORC performance under design and off-design conditions.
2017-03-28
Technical Paper
2017-01-0123
Saiful Bari
Abstract In general, diesel engines have an efficiency of about 35% and hence, a considerable amount of energy is expelled to the ambient air. In water-cooled engines, about 25%, 33% and 7% of the input energy are wasted in the coolant, exhaust gas, and friction, respectively. The heat from the exhaust gas of diesel engines can be an important heat source to provide additional power and improve overall engine efficiency. Studies related to the application of recoverable heat to produce additional power in medium capacity diesel engines (< 100 kW) using separate Rankine cycle are scarce. To recover heat from the exhaust of the engine, an efficient heat exchanger is necessary. For this type of application, the heat exchangers are needed to be designed in such a way that it can handle the heat load with reasonable size, weight and pressure drop. This paper describes the study of a diesel generator-set attached with an exhaust heat recovery system.
2017-03-28
Technical Paper
2017-01-0620
Chandrakant Parmar, Sethuramalingam Tyagarajan, Sashikant Tiwari, Ravindra Thonge, S Arun Paul
Abstract The engine compartment of passenger car application contains various source which radiates the produced heat and raises the temperature level of the compartment. The rise in compartment temperature increases the body temperature of individual component. The rise in body temperature of critical components can endanger the durability or functionality of the specific component or a system in which it operates. The aim of this paper is to strategize thermal protection of the rear mounted engine and its components of a vehicle having radiator and cooling fan mounted in front. An additional ventilation fan with speed sensor is fitted alongside rear mounted engine and a unique monitoring technique framed in the EMS ECU to protect critical components like HT cables, alternators, ECUs, wiring harness etc. from thermal damage. The EMS continuously monitors the engine speed, vehicle speed and the PWM signal of ventilation fan to ensure the intended operation of the ventilation fan.
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
2017-01-0554
Yu Li, Hongsheng Guo, Hailin Li
Abstract Computational fluid dynamics (CFD) model has been widely applied in internal combustion (IC) engine research. The integration of chemical kinetic model with CFD provides an opportunity for researchers to investigate the detailed chemical reactions for better understanding the combustion process of IC engines. However, the simulation using CFD has generally focused on the examination of primary parameters, such as temperature and species distributions. The detailed investigation on chemical reactions is limited. This paper presents the development of a post-processing tool capable of calculating the rate of production (ROP) of interested species with the known temperature, pressure, and concentration of each species in each cell simulated using CONVERGE-SAGE CFD model.
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).
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