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Viewing 1 to 30 of 6215
2017-03-28
Technical Paper
2017-01-0829
Gina M. Magnotti, Caroline L. Genzale
The atomization and initial spray formation processes in direct injection engines are not well understood due to the experimental and computational challenges associated with resolving these processes. Although different physical mechanisms, such as aerodynamic-induced instabilities and nozzle-generated turbulence and cavitation, have been proposed in the literature to describe these processes, direct validation of the theoretical basis of these models under engine-relevant conditions has not been possible to date. Recent developments in droplet sizing measurement techniques offer a new opportunity to evaluate droplet size distributions formed in the central and peripheral regions of the spray. There is therefore a need to understand how these measurements might be utilized to validate unobservable physics in the near nozzle-region.
2017-03-28
Technical Paper
2017-01-0849
Chao Gong, Roland Baar
The present work has its technical background in the field of Diesel injection systems of combustion engines and compares the effects of two kinds of remedies (re-meshing technique and linear interpolation technique) on mesh deformation. Mathematical formulation of moving grids has been proposed to guide the change of cell volume before. In this study, CFD (Computational Fluid Dynamics) analysis was mainly involved to study the internal nozzle behaviours and spray characteristics. An external library concept was introduced to couple the internal nozzle injection process with spray formation. In addition, all dynamic simulations were performed under a double-axis system. The comparison between simulation and experimental results shows that the integration of the traditional mesh deformation technique with the re-meshing or linear interpolation technique can repair mesh deformation and further contribute to better simulation results.
2017-03-28
Technical Paper
2017-01-0847
Ming Ge, Xingyu Liang, Hanzhengnan Yu, Yuesen Wang, Hongsheng Zhang
Spray impacting on a lube oil film with a finite thickness is a common phenomenon in IC engines and plays a critical role in the fuel-air mixture process and combustion. With the use of early injection strategy to achieve HCCI combustion mode in diesel engines, this phenomenon becomes more and more prominent. In addition, oxygenated fuels such as methanol and ethanol are regarded as alternative fuel and additives to improve the overall performance of HCCI engine. Therefore, a better understanding about the role of lube oil film thickness in methanol-diesel and ethanol-diesel blended fuels spray/wall impingement is helpful for accumulating experimental data to establish a more accurate spray/wall impingement model and optimize the combustion in HCCI engines. In this paper, the effect of lube oil film thickness on the characteristics of spray/wall impingement of different fuels are investigated in a constant volume bomb test system.
2017-03-28
Technical Paper
2017-01-0666
Zhenbiao Zhou, Yi Yang, Michael Brear, Joshua Lacey, Thomas G. Leone, James E. Anderson, Michael H. Shelby
Autoignition in modern spark ignition (SI) engines occurs at different conditions to those in the standardized Research (RON) and Motor (MON) Octane Number tests. The Octane Index (OI) has been proposed to account for these differences, with OI=RON–K(RON-MON) related to the occurrence of knock in the modern engine by several methods. The so-called K value then quantifies the deviation of the modern engine operation from the standard RON and MON tests. This paper presents a comparison of different methods for calculating the K value for the same modern engine operating with direct injection (DI), port fuel injection (PFI) and homogeneous, upstream fuel injection (UFI). The test fuels used span a wide range of RONs and fuel sensitivities (S=RON-MON). The quality of the results obtained using some of these methods were particularly dependent on the design of the test fuel matrix, with unreliable K values resulting in some cases.
2017-03-28
Technical Paper
2017-01-1640
Peng Liu, Liyun Fan, Wenbo Peng, Xiuzhen Ma, Enzhe Song
A novel high-speed electromagnetic actuator for electronic fuel injection system of diesel engine is proposed in this paper. By using permanent magnet and annular flange, the design of novel actuator aims to overcome the inherent drawbacks of the conventional solenoid electromagnetic actuator, such as high power consumption and so on. The finite element model (FEM) of novel actuator is developed. Combined with design of experiments and finite element analysis, the second order polynomial response surface models (RSM) of electromagnetic force of novel actuator are produced by the least square principle. Then the influence mechanisms and interaction effects of key design variables on the electromagnetic characteristics of novel actuator are revealed by RSM.
2017-03-28
Technical Paper
2017-01-0846
Raul Payri, Gabriela Bracho, Pedro Marti-Aldaravi, Alberto Viera
In the present work a constant-pressure flow facility able to reach 15 MPa ambient pressure and 1000K ambient temperature has been employed to carry out experimental studies of the combustion process at Diesel-like conditions. The objective is to characterize the influence of boundary conditions on OH* and broadband chemiluminiscence intensity generated by the fuel combustion for passenger car and heavy duty diesel injectors. Three nozzle types were investigated: a spray B nozzle (diameter of 90um) and two heavy duty application nozzles (diameter of 194 um and 228 um respectively). The results showed that nozzle size have a substantial impact on the ignition event, affecting the premixed phase of the combustion and the ignition location. Concerning OH, for the small nozzle geometry (Spray B) the ECN standard methodology was applied; meanwhile, for bigger nozzles a different processing method is proposed based on intensity threshold criteria.
2017-03-28
Technical Paper
2017-01-0780
Dongwei Wu, Baigang Sun, Qinghe Luo, Xi Wang, Yunshan Ge
Hydrogen internal combustion engine has advantages in many aspects compared with traditional internal combustion engine. E.g. hydrogen is renewable energy and its source is more widely and more easily, so it can alleviate the traditional energy crisis; the hydrogen internal combustion engine has the higher efficiency and the lower emissions. The structure of hydrogen internal combustion engine is highly consistent with the traditional internal combustion engine, so users do not need to change a lot when using hydrogen internal combustion engine. The combustion characteristics of hydrogen-air mixture are great significance for the performance and control of hydrogen internal combustion engine and it is also the theory and technical difficulties in the process of designing hydrogen internal combustion engine. The model that can accurately predict the mixture combustion velocity in cylinder is very important. The combustion velocity is an important parameter for mixture combustion.
2017-03-28
Technical Paper
2017-01-0447
Zhe Li, Mike Dong, Dennis Harrigan, Michael Gardner
In gasoline Powertrain systems, the evaporative emission control (EVAP) system canister purge valve (CPV) can be actuated by pulse-width modulated (PWM) signals. The CPV is an electronically actuated solenoid. The PWM controlled CPV, when actuated, creates pressure pulsations in the system. This pulsation is sent back to the rest of the EVAP system. Given the right conditions, the fill limit vent valve (FLVV) inside the fuel tank can be excited. The FLVV internal components can be excited and produce noise. This noise can be objectionable to the occupants. Additional components within the EVAP system may also be excited in a similar way. This paper presents a bench test method using parts from vehicle’s EVAP system and other key fuel system components.
2017-03-28
Technical Paper
2017-01-0746
Pietro Matteo Pinazzi, Fabrice Foucher
Gasoline Compression Ignition (GCI) engine based on Gasoline Partially Premixed Combustion (GPPC) showed potential for high efficiency and reduced emission of NOx and Soot. However, because of the high octane number of gasoline, misfire and unstable combustion dramatically limit low load operating conditions. In previous work, seeding the intake of the engine with ozone showed potential for increasing the fuel reactivity of gasoline. The objective of this work was to evaluate the potential of ozone to overcome the low load limitations of a GCI engine. Experiments were performed in a single-cylinder light-duty CI engine fueled with 95 RON gasoline. Engine speed was set to 1500 rpm and intake pressure was set to 1 bar in order to investigate typical low load operating conditions. In these conditions, high intake temperatures, not available during conventional engine operations, were necessary to enable gasoline autoignition.
2017-03-28
Technical Paper
2017-01-0693
Seungwoo Kang, Wonkyu Cho, Choongsik Bae, Youngho Kim
This paper investigated the influence of injector nozzle hole number on fuel consumption and exhaust emission characteristics of diesel engine. The engine used for the experiment was the 0.4L single-cylinder compression ignition engine which is modified from an 1.6L four-cylinder automotive diesel engine. The fuel injection equipment were operated under 250MPa injection pressure. Three injectors with identical hydraulic flow rate with various combinations of the nozzle hole number(8, 9, and 10) and diameter(105 μm, 100 μm, 95 μm) were compared. The indicated specific fuel consumption and NOx emission of three injectors were on same level because of the identical fuel flow rates and similar in-cylinder pressure traces. Without EGR, the particulate matter(PM) emission were lower with larger nozzle hole number. However, the NOx-PM trade-off were similar at low oxygen concentration with high EGR rate.
2017-03-28
Technical Paper
2017-01-0694
Tae Joong Wang, Jong Yoon Lee, Seung Kwon Hwang, Ja Yun Cho, Jeong Keun Park, Woong Gun Lee, Tae Sub Kim, Sang Won Jeong, Tae Kuk Kim
Doosan Infracore Corporation has developed the combustion system of a brand-new DX12 heavy-duty diesel engine equipped for 38 ~ 50 tonnage excavators and 4.2 ~ 4.5 m3 bucket-size wheel loaders which are mainly targeted to emerging countries. A variety of advanced combustion technologies were incorporated in the design of the DX12 engine to meet Tier3 emission legislation even with a mechanically controlled fuel injection equipment while ensuring around 2 % improvement in fuel consumption as well as over 8 % increase in rated power than its Tier2 predecessor. Mechanical-type diesel engine has a couple of significant advantages especially in terms of cost and maintenance compared to electronic-type counterpart. In addition, mechanical fuel system is better able to tolerate a low fuel quality which is potentially possible in emerging countries.
2017-03-28
Technical Paper
2017-01-0763
Ehsan Faghani, Pooyan Kheirkhah, Christopher W.J. Mabson, Gordon McTaggart-Cowan, Patrick Kirchen, Steve Rogak
High-pressure direct-injection (HPDI) in heavy duty engines allows a natural gas (NG) engine to maintain diesel-like performance while deriving most of its power from NG. A small diesel pilot injection (5-10% of the fuel energy) is used to ignite the direct injected gas jet. The NG burns in a predominantly mixing-controlled combustion mode which can produce particulate matter (PM). Here we study the effect of injection strategies on emissions from a HPDI engine in two parts. Part-I investigated the effect of late post injection (LPI); the current paper (Part-II) reports on the effects of slightly premixed combustion (SPC) on emission and engine performance. In SPC operation, the diesel injection is delayed, allowing more premixing of the natural gas prior to ignition. PM reductions and tradeoffs involved with gas slightly premixed combustion was investigated in a single-cylinder version of a 6-cylinder, 15 liter HPDI engine.
2017-03-28
Technical Paper
2017-01-0774
Ehsan Faghani, Pooyan Kheirkhah, Christopher W.J. Mabson, Gordon McTaggart-Cowan, Patrick Kirchen, Steve Rogak
High-pressure direct-injection (HPDI) in heavy duty engines allows a natural gas (NG) engine to maintain diesel-like performance while deriving most of its power from NG. A small diesel pilot injection (5-10% of the fuel energy) is used to ignite the direct injected gas jet. The NG burns in a predominantly non-premixed combustion mode which can produce particulate matter (PM). Here we study the effect of injection strategies on emissions from a HPDI engine in two parts. Part-I will investigates the effect of late post injection (LPI) and Part II will study the effect of slightly premixed combustion (SPC) on emission and engine performance. PM reductions and tradeoffs involved with gas late post-injections (LPI) was investigated in a single-cylinder version of a 6-cylinder,15 liter HPDI engine. The post injection contains 10-25% of total fuel mass, and occurs after the main combustion event.
2017-03-28
Technical Paper
2017-01-0124
V N Bhasker, Abhinav Agarwal, Abhishek Sharma, Avisek Das, Nirajkumar Mishra
ABSTRACT Vehicle heat management has become a serious concern due to escalating under-hood and exhaust temperatures. Tight vehicle packaging caused by downsizing has further magnified this concern. In an automobile, fuel is stored in a metal or plastic container known as fuel tank. In addition to fuel storage, temperature inside fuel tank has to be maintained at a certain level to control high fuel evaporation rate and prevent deterioration of other systems part performance. In case of under-body fuel tank layout, fuel tank surface temperature is governed by engine, exhaust system layout and road loads. Mechanical shielding has been found to be an efficient defence to the heat management problem. However, what to shield, where to place the shield and the best shield material are major design challenges. This paper focuses on different approaches followed to reduce temperature on fuel tank surface by varying material, geometry & layout of heat insulators.
2017-03-28
Technical Paper
2017-01-0753
Marcus Olof Lundgren, Zhenkan Wang, Alexios Matamis, Oivind Andersson, Mattias Richter, Martin Tuner, Marcus Alden, Andersson Arne
Gasoline partially premixed combustion (PPC) has shown potential in terms of high efficiency with low NOx and soot emissions. Despite its benefits, emissions of unburned hydrocarbons (uHC) and carbon monoxide (CO) are the main shortcomings of the concept. These are caused by overlean zones near the injector tip. However, previous diesel low temperature combustion (LTC) research have demonstrated post injections to be an effective strategy to mitigate these emissions. The main objective of this work is to investigate the impact of post injections on CO and uHC emissions in a non-swirling geometry. A blend of primary reference fuels, PRF87, having properties similar to US pump gasoline was used at PPC conditions in a heavy duty optical engine. The start of the main injection was maintained constant. Dwell and mass repartition between the main and post injections were varied to evaluate their effect. All points were run at 7 bar IMEPg.
2017-03-28
Technical Paper
2017-01-0652
Jose Claret, Thomas Lauer, Nikola Bobicic, Andreas Posselt, Joerg Schlerfer
Upcoming stringent limits for particulate numbers (PN) of spark ignited (SI) engines imply further challenges for the combustion process development. Wall film formation within the combustion chamber is a major source of particle generation through non-premixed turbulent combustion. This study presents a methodology to predict particle generation from wall wetting employing numerical CFD simulation and fuel film analysis. The engine parameters spray pattern, injection timing, intake valve timing, as well as engine load/speed were varied and their impact on wall film and PN was evaluated. A naturally aspirated 4-cylinder gasoline engine with port-fuel injection was investigated at wide open throttle. It was equipped with soot particle sampling technology and optical access to the combustion chamber of cylinder 1. In-cylinder high-speed visualisation revealed a notable presence of non-premixed turbulent flames, which were typically initiated between the valve seats and cylinder head.
2017-03-28
Technical Paper
2017-01-0739
Amin Maghbouli, Tommaso Lucchini, Gianluca D'Errico, Mohammad Izadi Najafabadi, Bart Somers
Partially premixed compression ignition combustion is one of the low temperature combustion techniques which is being actively investigated. This approach provides a significant reduction of both soot and NOx emissions. Comparing to the homogeneous charge compression ignition mode, PPCI combustion provides better control on ignition timing and noise reduction through air- fuel mixture stratification which lowers heat release rate com- pared to other advanced combustion modes. In this work, CFD simulations were conducted for a low and a high air-fuel mix- ture stratification cases on a light-duty optical engine operating in PPCI mode. Such conditions for PRF70 as fuel were experimen- tally achieved by injection timing and spray targeting at similar thermodynamic conditions.
2017-03-28
Technical Paper
2017-01-0779
Wolfgang Friedrich, Roman Grzeszik, Philipp Lauschke, Vadim Zelenov, Michael Wensing
A previous study by the authors has shown an efficiency benefit of up to 27 % for stratified operation of a high pressure natural gas direct injection (DI) spark ignition (SI) engine compared to the homogeneous stoichiometric operation. NOx and CO raw emissions in stratified operation were also found lower compared to the homogeneous stoichiometric operation. While best efficiencies appeared at extremely lean operation at lambda = 3.2, minimum HC emissions were found at lambda = 2. The increasing HC emissions and narrow ignition time frames in the extremely lean stratified operation have given the need to further investigate the mixture formation and flame propagation under these conditions. An optically accessible single-cylinder engine was used for a detailed analysis of the engine process. The mixture formation and the flame luminosity have been investigated in two perpendicular planes inside the combustion chamber.
2017-03-28
Technical Paper
2017-01-0832
Jacob Temme, Vincent Coburn, Chol-Bum Kweon
The objective of the study was to investigate the spray and combustion characteristics of Jet Propellant- 8 (JP-8) using a high-pressure fuel injector which is capable of up to 250-MPa fuel injection pressure. Experiments were performed in a constant-pressure flow-through combustion chamber at the ambient conditions of 825 K and 6 MPa for the oxygen concentration of 0 and 21%. JP-8 was injected over a range of fuel injection pressures from 50 to 250 MPa for single injection events to establish a baseline operation. Pilot and post injections were used to study the effect of multiple injections on spray and combustion of the high-pressure fuel injector. Both pilot and post injection separation times and quantities were systematically varied. JP-8 spray and combustion events were imaged at 75 kHz using a combination of Mie scattering and OH* chemiluminescence imaging.
2017-03-28
Technical Paper
2017-01-0823
Alessandro Mariani, Andrea Cavicchi, Lucio Postrioti, Carmine Ungaro
In the present paper, a new methodology for the estimation of the single hole mass quantity by a GDI injector is presented and discussed. The GDI injector used for the activity was a five holes nozzle characterized by three holes with the same diameter and two hole with a larger diameter. The different diameters guarantee a significant difference in terms of mass flow. The new methodology described is based on the measurement of the global momentum flow of each single plume and the combination of this measurement with the global mass measurement made with the gravimetric principle. The momentum flux is measured by means of a dedicated test bench that detects the impact force of single spray plume at different distances. The sensing device is moved in different positions and in each point, the force trace averaged on several injection events is acquired.
2017-03-28
Technical Paper
2017-01-0865
Mark Walls, Michael Joo, Michael Ross
Liquefied petroleum gas (LPG) is commonly known as autogas when used as a fuel for internal combustion engines. Autogas is primarily made up of propane, but can contain small amounts of butane, methane and propylene. Autogas is not a new fuel for internal combustion engines, but as engine technology evolves, the properties of autogas can be utilized to improve engine and vehicle efficiency. With support from the Propane Education & Research Council (PERC), Southwest Research Institute (SwRI) performed testing to quantify efficiency differences with liquid autogas direct injection in a modern downsized and boosted direct-injected engine using the production gasoline fuel injection hardware. Engine dynamometer testing demonstrated that autogas produced similar performance characteristics to gasoline at part load, but could be used to improve brake thermal efficiency at loads above 12 bar BMEP.
2017-03-28
Technical Paper
2017-01-0537
Murat Ates, Ronald D. Matthews, Matthew J. Hall
A quasi-dimensional model for a direct injection diesel engine was developed based on prior research at Sandia National Laboratory. The Sandia researchers obtained various images describing diesel spray evolution, spray mixing, premixed combustion, mixing controlled combustion, soot formation, and NOx formation. Dec 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
2017-01-1020
Finn Tseng, Imad Makki, Pankaj Kumar, Robert Jentz, Aed Dudar
Engine-Off Natural Vacuum (EONV) principles based leak detection monitors are designed to determine the presence of a small leak in the fuel tank system. It was introduced to address the ever more stringent emission requirement (currently at 0.02”) for gasoline engine equipped vehicles as proposed by the Environmental Protection Agency (EPA) and California Air Resources Board (CARB) in the United States [2, 3]. Other environmental protection agencies including the ones in EU and China will be adopting similar regulations in the near future. Due to its sensitivity to known noise factors such as the ambient temperature, barometric pressure, drive pattern and parking angle, it has been historically a lower performing monitor that is susceptible to warranty cost or even voluntary recalls. The proposed new model based monitor utilizes production pressure signal and newly instrumented temperature sensors [15].
2017-03-28
Technical Paper
2017-01-0831
Jie Yang, Xue Dong
Flash-boiling spray could be one promising approach to better suit for direct injection gasoline engine, since previous study demonstrated in constant chamber that flash-boiling fuel spray provides desirable spray structure with shorter penetration, more homogeneous fuel distribution, smaller droplets and quicker evaporation. However, in a real engine intake air flow have significant influence on spray development which is also one major source of cycle-to-cycle variation of engine performance. In this research, the effect of engine speed and swirl ratio on the structure of flash-boiling sprays of gasoline was investigated in an optical accessible, single-cylinder spark-ignition direct-injection (SIDI) engine with an 8-hole injector. Experiment was carried out at cold engine conditions (30oC coolant and oil temperature) under different engine speed (800, 1200, 2000 rpm).
2017-03-28
Technical Paper
2017-01-0838
Sayop Kim, Dorrin Jarrahbashi, Caroline Genzale
This study investigates the role of turbulent-chemistry interaction in CFD simulations of diesel spray combustion phenomena after end-of-injection (EOI). Recent experimental and computational studies have shown that the spray flame dynamics and mixture formation after EOI are governed by highly turbulent entrainment, coupled with rapid evolution of the thermo-chemical state of the mixture field.. A few studies have shown that after EOI, mixtures between the nozzle and the lifted diffusion flame can ignite and appear to propagate back towards the injector nozzle via an auto-ignition reaction sequence under sufficiently reactive ; referred to as “combustion recession”. Because combustion recession is a highly-coupled transient turbulent-chemistry phenomenon, questions remain regarding the role of non-linear coupling between turbulent mixing and reactive scalars on observed combustion outcomes.
2017-03-28
Technical Paper
2017-01-0707
Srinivas Padala, Minh Khoi Le, Yoshihiro Wachi, Yuji Ikeda
The effect of microwave enhanced plasma (MW Plasma) on diesel spray combustion was investigated inside a constant volume high pressure chamber. A microwave-enhanced plasma system, in which plasma discharge generated by a spark plug was amplified using microwave pulses, was used to introduce plasma. Initially, the plasma was introduced to the diesel spray before the occurrence of auto-ignition, to understand the effect of additional oxidizer entertainment on ignition delay of diesel spay. High speed imaging of natural luminosity indicated an earlier appearance of flame in the with-plasma cases compared to the respective without-plasma conventional operation. These results corresponds well to the behavior of the heat-release rates, suggesting a reduction-effect by MW plasma on the ignition delay of diesel combustion. Later, the plasma was introduced downstream the flame lift-off and in the soot cloud to estimate the soot reduction effect by plasma.
2017-03-28
Technical Paper
2017-01-0721
Michele Bardi, Gilles Bruneaux, André Nicolle, Olivier Colin
This paper is a contribution to the understanding of the formation and oxidation of soot in typical Diesel combustion. A common rail ECN spray A injector (single axial-oriented orifice) was tested in a optically accessible test-chamber at engine relevant conditions. High-speed OH* and high-speed 2D extinction imaging were performed simultaneously to link together the flame chemistry and the soot data information. The experiments were carried out for different fuels (EU Diesel, JetA1, n-dodecane) performing parametric variations of the boundary conditions. The proposed analysis methodology enabled the identification of the sooting behavior of each fuel by evaluating the relationship between two of the measured parameters, namely lift-off length and the soot maximum axial extinction value (Max KL). The relationship between these two parameters allowed to distinguish the behavior of the different fuels.
2017-03-28
Technical Paper
2017-01-1287
Markus Sartory, Markus Justl, Patrick Salman, Alexander Trattner, Manfred Klell, Ewald Wahlmüller
As the availability of hydrogen filling stations is highly limited, cost effective and flexible solutions for decentralized hydrogen production are needed. Therefore a modular, scalable and highly efficient hydrogen supply infrastructure for industrial, automotive and mobile applications is developed and presented in this paper. The modular system design consists of a 35 MPa electrolysis system, an optional 70 MPa single stage compressor for automotive applications, storage and dispenser modules as well as the required peripheral components. The number of electrolysis modules can be varied application-oriented and therefore customer-specific solutions can be realized. The flexible concept can be adapted to the actual hydrogen demand and is optimized for any application regarding capacity utilization and cost effectiveness.
2017-03-28
Technical Paper
2017-01-0661
Michael Pamminger, James Sevik, Riccardo Scarcelli, Thomas Wallner, Carrie Hall
Natural Gas (NG) is an alternative fuel which has attracted a lot of attention recently, in particular in the US due to shale gas availability. The higher hydrogen-to-carbon (H/C) ratio, compared to gasoline, allows for decreasing carbon dioxide emissions throughout the entire engine map. Furthermore, the high knock resistance of NG allows increasing the efficiency at high engine loads compared to fuels with lower knock resistance. NG direct injection (DI) allows for fuel to be added after intake valve closing (IVC) resulting in an increase in power density compared to an injection before IVC. Steady-state engine tests were performed on a single-cylinder research engine equipped with gasoline (E10) port-fuel injection (PFI) and NG DI to allow for in-cylinder blending of both fuels. Knock investigations were performed at two discrete compression ratios (CR), 10.5 and 12.5.
2017-03-28
Technical Paper
2017-01-0482
Cristiano Grings Herbert, Luiz Rogério De Andrade Lima, Cristiane Gonçalves
Phthalates have been extensively used in rubbers formulation as plasticizer additive for PVC and NBR promoting processing parameters or reducing cost. The most commonly used plasticizer in PVC compounds was di-2-ethylhexyl phthalate (DEHP) currently not recommend due toxicity. In many studies it is described that DEHP is liable of producing toxic and adverse effects and able to act as potential carcinogenic agent. Therefore it is listed as prohibited to the Global Automotive Declarable Substance List (GADSL). Phthalates alternatives are already available but the compatibility in automotive fuel system with biodiesel was not extensively understood. This aspect is important since plasticizer may migrate and change rubber properties. Tri-2-ethylhexyl trimellitate (TOTM) and di-2-ethylhexyl terephthalate (DEHT) plasticizers have been studied the carcinogenicity and chronic toxicity potential and the migration to blood in medical devices.
Viewing 1 to 30 of 6215