Criteria

Text:
Display:

Results

Viewing 1 to 30 of 12493
2017-10-08
Technical Paper
2017-01-2429
Felix Leach, Martin Davy, Adam Weall, Brian Cooper
Diesel engine designers often use swirl flaps to increase air motion in cylinder at low engine speeds, where lower piston velocities reduce natural in-cylinder swirl. Such in-cylinder motion reduces smoke and CO emissions by improved fuel-air mixing. However, swirl flaps, acting like a throttle on a gasoline engine, create an additional pressure drop in the inlet manifold and thereby increase pumping work and fuel consumption. In addition, by increasing the fuel-air mixing in cylinder the combustion duration is shortened and the combustion temperature is increased; this has the effect of increasing NOx emissions. Typically, EGR rates are correspondingly increased to mitigate this effect. Late inlet valve closure, which reduces an engine’s effective compression ratio, has been shown to provide an alternative method of reducing NOx emissions.
2017-10-08
Technical Paper
2017-01-2201
Zhongye Cao, Tianyou Wang, Kai Sun, Lei Cui
In uniflow scavenged two-stroke marine diesel engines, the main function of scavenging process is to replace the burned gas with fresh charge. It is integral to the subsequent combustion process, thereby affecting the engine's fuel economy, power output and emission performance. In this paper, a complete working cycle of 6S35ME engine of MAN Diesel&Turbo was simulated by using the CFD software CONVERGE with full engine geometry including intake and exhaust ports. The simulation based on RANS and standard k-epsilon model was in good agreement with experiment. Based on the above calibrated model, the influence of exhaust valve closing (EVC) timing and swirl ratio on the scavenging process were investigated.
2017-10-08
Technical Paper
2017-01-2257
Linjun Yu, Yanfei Li, Bowen Li, Hao-ye Liu, Zhi Wang, Xin He, Shi-jin Shuai
This study compares the combustion and emission performance of gasoline Homogeneous Charge Compression Ignition (HCCI) and Multiple Premixed Compression Ignition (MPCI) in a single-cylinder, intake-boosting and water-cooling diesel engine with a compression ratio of 16.7. The test fuel was commercial gasoline in China with RON of 92, and intake pressure varied from 0.16 to 0.21 MPa, while Indicated Mean Effective Pressure (IMEP) was fixed at 1.0 MPa. Both the knock limit and misfire limit of gasoline HCCI were studied. The results showed that Low Temperature Heat Release (LTHR) was observed before High Temperature Heat Release (HTHR) in gasoline HCCI, and the LTHR accounted for less than 10 percent of total heat release. The knock limit and misfire limit of gasoline HCCI coincided when the intake pressure decreased to 0.16 MPa. Increasing the intake pressure helped to promote the Indicated Thermal Efficiency (ITE) for both gasoline HCCI and MPCI.
2017-10-03 ...
  • October 3-4, 2017 (8:30 a.m. - 4:30 p.m.) - Troy, Michigan
Training / Education Classroom Seminars
As diesel engines become more popular, a fundamental knowledge of diesel technology is critical for anyone involved in the diesel engine support industry. This course will explain the fundamental technology of diesel engines starting with a short but thorough introduction of the diesel combustion cycle, and continue with aspects of engine design, emission control design, and more. An overview of developing technologies for the future with a comprehensive section on exhaust aftertreatment is also included. The text, Diesel Emissions and Their Control, authored by Magdi Khair and W. Addy Majewski is included with the seminar.
2017-09-21 ...
  • September 21-22, 2017 (8:30 a.m. - 4:30 p.m.) - Troy, Michigan
Training / Education Classroom Seminars
Engine failures can occur in a variety of equipment, vehicles, and applications. On occasion, a single vehicle type or equipment family will even experience multiple engine failures leading to the inevitable need to determine what the most likely cause of one or all of those failures was. This comprehensive seminar introduces participants to the methods and techniques used to understand the types of variables and inputs that can affect engine reliability and then determine the most likely cause of an individual engine or group of engine failures in the field.
2017-09-19
Technical Paper
2017-01-2136
Almuddin Rustum Sayyad, Pratik Salunke, Sangram Jadhav
The objective of this work is to optimize the operating parameters of the Direct Injection single cylinder (5.2 kw) CI engine with respect to Brake Thermal Efficiency (BTHE), Hydro carbons (HC) and Carbon dioxide (CO2). For this investigation, we used Simarouba Biodiesel as an alternate fuel for diesel fuel which possesses low cetane number which is not sufficient to operate existing diesel engine. However, this could be combined with the diesel fuel in the form of blends. For this investigation four levels and four parameters were selected viz. Injection Pressure (IP), Fuel Fraction (FF), Compression Ratio (CR) and Injection Timing (Before TDC). Taguchi Method is used for minimizing the number of experiments and Multiple Regression Analysis is used to find the optimum condition. Three outputs variables such as; Brake Thermal Efficiency (BTHE), content of HC particles and CO2 in the emission are measured and considered its influence on CI Engine performance.
2017-09-11 ...
  • September 11-12, 2017 (8:30 a.m. - 4:30 p.m.) - Troy, Michigan
Training / Education Classroom Seminars
Meeting the requirements of heavy-duty engine emissions regulations is a challenge for all engine manufacturers. Since the introduction of Exhaust Gas Recirculation (EGR) in medium and heavy-duty diesel engines, these systems have become more sophisticated and tightly integrated with emission control systems. This 2-day seminar will explore the advantages and disadvantages of EGR and the most effective implementation of various EGR systems. This seminar will begin by defining EGR and why it is used in diesel engines, along with an explanation of the mechanisms by which EGR is able to reduce NOx.
2017-09-04
Technical Paper
2017-24-0116
Ekarong Sukjit, Pansa Liplap, Somkiat Maithomklang, Weerachai Arjharn
In this study, two oxygenated fuels consisting of butanol and diethyl ether (DEE), both possess same number of carbon, hydrogen and oxygen atom but difference functional group, were blended with the waste plastic pyrolysis oil to use in a 4-cylinder direct injection diesel engine without any engine modification. In addition, the effect of castor oil addition to such fuel blends was also investigated. Four tested fuels with same oxygen content were prepared for engine test, comprising DEE16 (84% waste plastic oil blended with 16% DEE), BU16 (84% waste plastic oil blended with 16% butanol), DEE11.5BIO5 (83.5% waste plastic oil blended with 11.5% DEE and 5% castor oil) and BU11.5BIO5 (83.5% waste plastic oil blended with 11.5% butanol and 5% castor oil). The results found that the DEE addition to waste plastic oil increased more emissions than the butanol addition at low engine operating condition.
2017-09-04
Technical Paper
2017-24-0078
R. Vallinayagam, S. Vedharaj, Yanzhao An, Alaaeldin Dawood, Mohammad Izadi Najafabadi, Bart Somers, Junseok Chang, Mani Sarathy, Bengt Johansson
Abstract Light naphtha is the light distillate from crude oil and can be used in compression ignition (CI) engines; its low boiling point and octane rating (RON = 64.5) enable adequate premixing. This study investigates the combustion characteristics of light naphtha (LN) and its multicomponent surrogate under various start of injection (SOI) conditions. LN and a five-component surrogate for LN, comprised of 43% n-pentane, 12% n-heptane, 10% 2-methylhexane, 25% iso-pentane and 10% cyclo-pentane, has been tested in a single cylinder optical diesel engine. The transition in combustion homogeneity from CI combustion to homogenized charge compression ignition (HCCI) combustion was then compared between LN and its surrogate. The engine experimental results showed good agreement in combustion phasing, ignition delay, start of combustion, in-cylinder pressure and rate of heat release between LN and its surrogate.
2017-09-04
Technical Paper
2017-24-0080
Ross Ryskamp, Gregory Thompson, Daniel Carder, John Nuszkowski
Abstract Reactivity controlled compression ignition (RCCI) is a form of dual-fuel combustion that exploits the reactivity difference between two fuels to control combustion phasing. This combustion approach limits the formation of oxides of nitrogen (NOX) and soot while retaining high thermal efficiency. The research presented herein was performed to determine the influences that high reactivity (diesel) fuel properties have on RCCI combustion characteristics, exhaust emissions, fuel efficiency, and the operable load range. A 4-cylinder, 1.9 liter, light-duty compression-ignition (CI) engine was converted to run on diesel fuel (high reactivity fuel) and compressed natural gas (CNG) (low reactivity fuel). The engine was operated at 2100 revolutions per minute (RPM), and at two different loads, 3.6 bar brake mean effective pressure (BMEP) and 6 bar BMEP.
2017-09-04
Technical Paper
2017-24-0091
Hyun Woo Won, Alexandre Bouet, Joseph KERMANI, Florence Duffour
Abstract Reducing the CO2 footprint, limiting the pollutant emissions and rebalancing the ongoing shift demand toward middle-distillate fuels are major concerns for vehicle manufacturers and oil refiners. In this context, gasoline-like fuels have been recently identified as good candidates. Straight run naphtha, a refinery stream derived from the atmospheric crude oil distillation process, allows for a reduction of both NOx and particulate emissions when used in compression-ignition engines. CO2 benefits are also expected thanks to naphtha’s higher H/C ratio and energy content compared to diesel. In previous studies, wide ranges of Cetane Number (CN) naphtha fuels have been evaluated and CN 35 naphtha fuel has been selected. The assessment and the choice of the required engine hardware adapted to this fuel, such as the compression ratio, bowl pattern, nozzle design and air-path technology, have been performed on a light-duty single cylinder compression-ignition engine.
2017-09-04
Technical Paper
2017-24-0029
Tommaso Lucchini, Gianluca D'Errico, Tarcisio Cerri, Angelo Onorati, Gilles Hardy
Heavy-duty engines have to be carefully designed and optimized in a wide portion of their operating map to satisfy the emissions and fuel consumptions requirements for the different applications they are used for. Within this context, computational fluid dynamics is a useful tool to support combustion system design, making possible to test effects of injection strategies and combustion chamber design. Within this context, the predictive capability of the combustion model play a big role since it has to ensure accurate predictions in terms of cylinder pressure trace and the main pollutant emissions in a reduced amount of time. For this reason, both detailed chemistry and turbulence chemistry interaction need to be included. In this work, the authors intend to apply combustion models based on tabulated kinetics for the prediction of Diesel combustion in Heavy Duty Engines. Three different approaches were considered: well-mixed model, presumed PDF and flamelet progress variable.
2017-09-04
Technical Paper
2017-24-0048
Jose V. Pastor, Jose M. Garcia-Oliver, Antonio Garcia, Mattia Pinotti
In the past few years various studies have shown how the application of a highly premixed dual fuel combustion for CI engines leads a strong reduction for both pollutant emissions and fuel consumption. In particular a drastic soot and NOx reduction were achieved. In spite of the most common strategy for dual fueling has been represented by using two different injection systems, various authors are considering the advantages of using a single injection system to directly inject blends in the chamber. In this scenario, a characterization of the behavior of such dual-fuel blend spray became necessary, both in terms of inert and reactive ambient conditions. In this work, a light extinction imaging (LEI) has been performed in order to obtain two-dimensional soot distribution information within a spray flame of different diesel/gasoline commercial fuel blends. All the measurements were conducted in an optically accessible two-stroke engine equipped with a single-hole injector.
2017-09-04
Technical Paper
2017-24-0053
Silvio A. Pinamonti, Domenico Brancale, Gerhard Meister, Pablo Mendoza
The use of state of the art simulation tools to allow for effective front-loading of the calibration process is essential to off-set these additional efforts; therefore, the process needs a critical model validation where the correlation in dynamic conditions is used as a preliminary insight of representation domain of a mean value engine model. This paper focuses on the methodologies for correlating dynamic simulations with vehicle measured dynamic data (fundamental engine parameters and gaseous emissions) obtained using dedicated instrumentation on a diesel vehicle. This correlation is performed using simulated tests run within the AVL mean value model MoBEO (model based engine optimization).
2017-09-04
Journal Article
2017-24-0057
Roberto Finesso, Omar Marello, Ezio Spessa, Yixin Yang, Gilles Hardy
A model-based control of BMEP (Brake Mean Effective Pressure) and NOx emissions has been developed and assessed for a Euro VI 3.0L diesel engine for heavy-duty applications. The control is based on a zero-dimensional real-time combustion model, which is capable of simulating the HRR (heat release rate), in-cylinder pressure, brake torque, exhaust gas temperatures, NOx and soot engine-out levels. The real-time combustion model has been realized by integrating and improving previously developed simulation tools. The chemical energy release has been simulated using the accumulated fuel mass approach. The in-cylinder pressure was estimated on the basis of a single-zone heat release model, using the net energy release as input. The latter quantity was obtained starting from the simulated chemical energy release, and evaluating the heat transfer of the charge with the walls.
2017-09-04
Technical Paper
2017-24-0068
Roberto Finesso, Ezio Spessa, Yixin Yang, Giuseppe Conte, Gennaro Merlino
A real-time approach has been developed and assessed to control BMEP (brake mean effective pressure) and MFB50 (crank angle at which 50% of fuel mass has burnt) in a Euro 6 1.6L GM diesel engine. The approach is based on the use of feed-forward NNs (neural networks), which have been trained using virtual tests simulated by a previously developed low-throughput physical engine model. The latter is capable of predicting the heat release and the in-cylinder pressure, as well as the related metrics (MFB50, IMEP – indicated mean effective pressure) on the basis of an improved version of the accumulated fuel mass approach. BMEP is obtained from IMEP taking into account friction losses. The low-throughput physical model does not require high calibration effort and is also suitable for control-oriented applications. However, control tasks characterized by stricter demands in terms of computational time may require a modeling approach characterized by a further lower throughput.
2017-09-04
Technical Paper
2017-24-0066
Maria Cristina Cameretti, Roberta De Robbio, Raffaele Tuccillo
The present study deals with the simulation of a Diesel engine fuelled by natural gas/diesel in dual fuel mode to optimize the engine behaviour in terms of performance and emissions. In dual fuel mode, the natural gas is introduced into the engine’s intake system. Near the end of the compression stroke, diesel fuel is injected and ignites, causing the natural gas to burn. The engine itself is virtually unaltered, but for the addition of a gas injection system. The CO2 emissions are considerably reduced because of the lower carbon content of the fuel. Furthermore, potential advantages of dual-fuel engines include diesel-like efficiency and brake mean effective pressure with much lower emissions of oxides of nitrogen and particulate matter. In previous papers [1, 2, 3], the authors have presented some CFD results obtained by the KIVA 3V and Fluent codes by varying the diesel/NG ratio and the diesel pilot injection timing at different loads.
2017-09-04
Technical Paper
2017-24-0073
Carlo Beatrice, Giacomo Belgiorno, Gabriele Di Blasio, Ezio Mancaruso, Luigi Sequino, Bianca Maria Vaglieco
Technologies for direct injection of fuel in compression ignition engines are in continuous development in order to get an increasingly high injection pressure. One of the most investigated component of this system is the injector; in particular, main attention is given to the nozzles characteristics as diameter, number, angle, internal shape. The reduction of nozzle hole diameter seems the simplest way to increase the fuel velocity and to promote the atomization process. On the other hand, the number of the holes must increase to keep the desired mass flow. On this basis, a new logic has been applied for the development of the next generation of injectors. The tendency to increase the nozzle number and to reduce the diameter has led to the replacement of the nozzle with a circular plate that moves vertically. The plate motion allows to obtain a cylindrical surface for the delivery of the fuel on 360° degrees; while the plate lift is calibrated to obtain the desired fuel mass flow.
2017-09-04
Journal Article
2017-24-0072
Gabriele Di Blasio, Carlo Beatrice, Giacomo Belgiorno, Francesco Concetto Pesce, Alberto Vassallo
The paper describes the challenges and results achieved in developing a new high speed Diesel combustion system capable of exceeding the threshold of 100 kW/l. The high-quality state-of-art components of the automotive diesel technology was provided in order to set-up a single-cylinder research engine demonstrator. Key design parameters were identified in terms boost, speed, injection pressure and nozzle flow rates. In this regard, an advanced piezo injection system capable of 3000 bar maximum injection pressure was selected, coupled to a robust base engine featuring advanced combustion bowl and intake ports. The matching among the low compression ratio wide bowl, the high-density charge motion, engine speed and the highly efficient injector nozzles have been thoroughly examined and experimentally parametrized.
2017-09-04
Technical Paper
2017-24-0070
Stefano D'Ambrosio, Daniele Iemmolo, Alessandro Mancarella, Nicolò Salamone, Roberto Vitolo, Gilles Hardy
A precise estimation of the recirculated exhaust gas rate and oxygen concentration as well as a predictive evaluation of the possible EGR unbalance among cylinders are of paramount importance, especially if non-conventional combustion modes, which require high EGR flowrates, are implemented. In the present paper, starting from the equation related to convergent nozzles, the EGR mass flow-rate is modeled considering the pressure and the temperature upstream of the EGR control valve, as well as the pressure downstream of it. The restricted flow-area at the valve-seat passage and the discharge coefficient are carefully assessed as functions of the valve lift. Other models were fitted using parameters describing the engine working conditions as inputs, following a semi-physical and a purely statistical approach. The resulting models are then applied to estimate EGR rates to both conventional and non-conventional combustion conditions.
2017-09-04
Technical Paper
2017-24-0075
Felix Leach, Riyaz Ismail, Martin Davy, Adam Weall, Brian Cooper
Modern Diesel cars, fitted with state-of- the-art aftertreatment systems, have the capability to emit extremely low levels of pollutant species at the tailpipe. However, diesel aftertreatment systems can represent a significant complexity, packaging and maintenance requirement. Reducing engine-out emissions in order to reduce the scale of the aftertreatment system is therefore a high priority research topic. Engine-out emissions from diesel engines are, to a significant degree, dependent on the detail of fuel/air interactions that occur in-cylinder—both during the injection and combustion events—and also to the induced air motion in and around the bowl prior to injection. In this paper the effects of two different piston bowl shapes are investigated – one with a stepped bowl lip, and the other without.
2017-09-04
Technical Paper
2017-24-0076
Mark A. Hoffman, Ryan O'Donnell, Zoran Filipi
The proven impact of combustion chamber deposits on advanced compression ignition combustion strategies has steered recent works toward the development of thermal barrier coatings, which can mimic their benefits on combustion efficiency and operational range expansion. However, recent work based on statistical thermodynamics has indicated that inter-molecular radiation during the combustion event may subject the combustion chamber walls to non-negligible radiation heat transfer, regardless of the relatively low soot formation within the well-mixed and lean charge. In the present paper, the impact of radiation heat transfer on combustion chamber deposits and thermal barrier coatings is studied. The morphological construction of the combustion chamber deposit layer is shown to be partially transparent to radiation heat transfer, drawing corollaries with ceramic based thermal barrier coatings.
2017-09-04
Technical Paper
2017-24-0129
Vladimir Merzlikin, Svetlana Parshina, Victoria Garnova, Andrey Bystrov, Alexander Makarov, Sergey Khudyakov
The core of this paper is reduction of exhaust emission and increase of diesel efficiency due to application of microstructure ceramic semitransparent heat-insulating coatings (SHIC). The authors conducted experimental study of thermal state of internal-combustion engine piston head with a heat-insulating layer formed by plasma coating method. The paper presents physical and mathematical simulation of improved optical (transmittance, reflectance, absorption, scattering) and thermo radiative (emittance) characteristics determining optimal temperature profiles inside SHIC. The paper considers the effect of subsurface volumetric heating up and analyzes temperature maximum position inside subsurface of this coating. Decrease of SHIC surface temperature of the coated piston in comparison with temperature of traditional opaque heat-insulating coatings causes NOx emission reduction.
2017-09-04
Technical Paper
2017-24-0123
Christopher Eck, Futoshi Nakano
Small commercial vehicles (SCV) with Diesel engines require efficient exhaust aftertreatment systems to reduce the emissions while keeping the fuel consumption and total operating cost as low as possible. To meet current emission legislations in all cases, a diesel oxidation catalyst (DOC) and diesel particulate filter (DPF) and some NOx treatment device (e.g. a lean NOx trap or selective catalytic reduction, SCR) are required. Creating a cost-effective SCV also requires to keep the cost for the aftertreatment system as low as possible because the contribution to total vehicle cost is high. By using more sophisticated and more robust operating strategies and control algorithms, the hardware cost can be reduced. To keep the calibration effort at a low level, it is necessary to apply only algorithms which have a time-efficient calibration procedure. This paper will focus on the active regeneration of the DPF.
2017-09-04
Technical Paper
2017-24-0124
Michael Maurer, Peter Holler, Stefan Zarl, Thomas Fortner, Helmut Eichlseder
To fulfil the new European real driving emissions (RDE) legislation, the LNT operation strategy – especially for DeNOx events – has to be optimized to minimize NOx as well as CO and HC emissions. On one hand the DeNOx purges should be long enough to fully regenerate the lean NOx trap, on the other hand the purges should be as short as possible to reduce the fuel consumption penalty from rich mode. Fundamental experiments have been conducted on a synthetic-gas-test-bench, purposely designed to test LNT catalysts. This methodology allowed to remove NOx from the gasfeed after the lean storage phase. The actually reduced amount of NOx could be easily calculated from the NOx storage before a regeneration minus the NOx that was desorbed during the DeNOx event and afterwards thermally desorbed NOx. To show the effect of aging method on the regeneration characteristics, tests have been performed with a in a car endurance run aged LNT and a synthetic hydrothermally aged LNT.
2017-09-04
Technical Paper
2017-24-0139
Francesco Barba, Alberto Vassallo, Vincenzo Greco
The aim of the present study is to improve the effectiveness of the engine and aftertreatment calibration process through the critical evaluation of several methodologies available to estimate the soot mass flow produced by diesel engines and filtered by Diesel Particulate Filters (DPF). In particular, the focus of the present study has been the development of a reliable simulation method for the accurate prediction of the engine-out soot mass flow starting from Filter Smoke Number (FSN) measurements executed in steady state conditions, in order to predict the DPF loading considering different engine working conditions corresponding to NEDC and WLTP cycles. In order to achieve this goal, the study was split into two parts: - Correlation between ‘wet soot’ (measured by soot filter weighing) and the ‘dry soot’ (measured by the Micro Soot Sensor MSS).
2017-09-04
Technical Paper
2017-24-0137
Zhen Zhang, Luigi del Re, Richard Fuerhapter
During transients, engines tend to produce substantially higher peak emissions which are the longer the more important as the steady state emissions are better controller. To this end, they must be measurable in an adequate time scale. While for most emissions there are commercially available sensors of sufficient speed and performance, the same is not true for soot, especially for production engines. Against this background, in the last years we have investigated together with a supplier of measurement systems the possible use of a 50Hz sensor based on LII and of the same size of a standard oxygen probe, and the results were very positive, showing that the sensor could recognize transient changes undetected by conventional measurement systems (like AVL Opacimenter or Microsoot) but confirmed e.g. by incylinder 2 color spectroscopy. The higher speed is also due to the position, as the sensor can be mounted above or below the turbine in a turbocharged CI engine.
2017-09-04
Technical Paper
2017-24-0143
Sathaporn Chuepeng, Kampanart Theinnoi, Manida Tongroon
The combustion in reactivity controlled compression ignition (RCCI) mode of diesel engine have been gained more attention as one among other strategies to increase operating range for premixed combustion and to improve fuel economy. A low reactivity fuel such as high octane number fuel, alcohol blends for example, is early fumigated (or injected) and premixed with air prior to induction to the combustion chamber. Later on adjacent to the end of the compression stroke, the diesel fuel as a high reactivity fuel is directly injected into the homogeneous pre-mixture and ignited. This can also promote lower nitrogen oxides and particulate matter emissions. The main aim of this work is to characterize the combustion phenomena and particulate matter in nano-size from the RCCI engine using neat hydrous ethanol as the low reactivity fuel.
Viewing 1 to 30 of 12493

Filter

  • Range:
    to:
  • Year: