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2017-09-04
Technical Paper
2017-24-0042
Ali Jannoun, Xavier Tauzia, Pascal Chesse, Alain Maiboom
Residual gas plays a crucial role in the combustion process of spark ignited engines. It acts as a diluent and has a huge impact on pollutant emissions (NOx and CO emissions), engine efficiency and tendency to knock. Therefore, characterizing the residual gas fraction is an essential task for engine modelling and calibration purposes. Thus, an in-cylinder sampling technique was developed on a spark ignited VVT engine to measure residual gas fraction during the compression phase. Two gas sampling valves were flush mounted to the combustion chamber walls; they are located between the intake valves and between intake and exhaust valves respectively. Sampled gas was stocked in a sampling bag using a vacuum pump and measured with a standard gas analyzer. This paper describes in details the sampling technique and proposes a methodology allowing the evaluation of the residual gas fraction. For this purpose, five kinds of tests were undertaken.
2017-09-04
Technical Paper
2017-24-0021
Sabino Caputo, Federico Millo, Giancarlo Cifali, Francesco Concetto Pesce
One of the key technologies for the improvement of the diesel engine thermal efficiency is the reduction of the engine heat transfer through the thermal insulation of the combustion chamber. This paper presents a numerical investigation on the effects of the combustion chamber insulation on the heat transfer, thermal efficiency and exhaust temperatures of a 1.6 l passenger car, turbo-charged diesel engine. First, the complete insulation of the engine components, like pistons, liner, firedeck and valves, has been simulated. This analysis has showed that the piston is the component with the greatest potential for the in-cylinder heat transfer reduction (ideally up to 46 %) and for Brake Specific Fuel Consumption (BSFC) reduction (up to 9 %), while firedeck, liner and valves only contribute respectively to 23 %, 19 % and 15 % in heat transfer decrease.
2017-09-04
Technical Paper
2017-24-0161
Noboru Uchida, Hideaki Osada
It can’t be avoided reducing heat loss from in-cylinder wall for further improvement in brake thermal efficiency (BTE). Especially for diesel engines, spray flame interference on the cavity and piston top wall during combustion period could be a major cause of the heat loss. To reduce heat transfer between hot gas and cavity wall, thin Zirconia layer (0.5mm) on the cavity surface of the forged steel piston was firstly formed by thermal spray coating aiming higher surface temperature swing precisely synchronized with flame temperature near the wall resulting in the reduction of temperature difference. However, no apparent difference in the heat loss was observed. On the contrary, BTE was deteriorated by the increase in other energy losses. To find out the reason why heat loss was not so improved, direct observation of flame impingement to the cavity wall was carried out with the top view visualization technique, for which one of the exhaust valves was modified to a sapphire window.
2017-09-04
Technical Paper
2017-24-0156
Minh Khoi Le, Srinivas Padala, Atsushi Nishiyama, Yuji Ikeda
The Microwave Discharge Igniter (MDI) was developed to create microwave plasma for the improvement of ignition inside combustion engines. The MDI plasma discharge is generated using the principle of microwave resonance with microwave (MW) originating from a 2.45 GHz semiconductor oscillator; it is then further enhanced and sustained using MW from the same source. The flexibility in the control of semiconductors allows multiple variations of MW parameters for MDI, which in turn, affects the resonating plasma characteristics and subsequently the combustion performance. In this study, a wide range of different controlling parameters of MDI and MW signal were selected for a parametric study of the generated Microwave Plasma. Schlieren imaging of the MDI-ignited propane flame were carried out to assess the impact on combustion quality of different MW parameters combinations.
2017-09-04
Technical Paper
2017-24-0145
Marco Piumetti, Debora Fino, Nunzio Russo, Samir Bensaid, Melodj Dosa
A set of CeO2 nanocatalysts with different structural properties (nanocubes, nanorods, high-surface area CeO2) was prepared to investigate the shape-dependency activity for two oxidation reactions: the soot combustion under different soot-catalyst contact conditions (namely, in “loose” and “tight” conditions) and the CO oxidation. The physico-chemical properties of the prepared materials were investigated by complementary techniques (XRD, N2-physisorption at -196 °C, H2-TPR, FESEM, TEM, micro-Raman, FT-IR, XPS). As a whole, the best performances in terms of soot combustion have been achieved for the CeO2-nanocubes (SBET = 4 m2g-1), due to the abundance of highly reactive (100) and (110) exposed surfaces. On the other hand, better results in terms of the onset of soot oxidation (T10%) have been obtained for high-surface-area materials (SBET = 75 m2g-1), thus reflecting the key role of the surface area at low reaction temperature.
2017-09-04
Technical Paper
2017-24-0136
Kurtis James Irwin, Roy Douglas, Jonathan Stewart, Andrew Pedlow, Rose Mary Stalker, Andrew Woods
With emission legislations becoming ever more stringent there is an increased pressure on the after treatment systems and more specifically the three-way catalysts. With more recent developments in emission legislations, there is requirement for more complex after-treatment systems and understanding of the ageing process. With future legislation introducing independent inspection of emissions at any time under real world driving conditions throughout a vehicle life cycle this is going to increase the focus on understanding catalyst behaviour during any likely conditions throughout its lifetime and not just at the beginning and end. In recent years it has become a popular approach to use accelerated aging of the automotive catalysts for the development of new catalytic formulations and for homologation of new vehicle emissions.
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
2017-24-0116
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
2017-24-0076
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
2017-24-0070
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.
2017-07-10
Technical Paper
2017-28-1939
Maruti Patil, Penchaliah Ramkumar, Shankar Krishnapillai
Abstract Minimum weight and high-efficiency gearboxes with the maximum service life are the prime necessity of today’s high-performance power transmission systems such as automotive and aerospace. Therefore, the problem to optimize the gearboxes is subjected to a considerable amount of interest. To accomplish these objectives, in this paper, two generalized objective functions for two stage spur-gearbox are formulated; first objective function aims to minimize the volume of gearbox material, while the second aims to maximize the power transmitted by the gearbox. For the optimization purpose, regular mechanical and critical tribological constraints (scuffing and wear) are considered. These objective functions are optimized to obtain a Pareto front for the two-stage gearbox using a specially formulated discrete version of non-dominated sorting genetic algorithm (NSGA-II) code written MATLAB. Two cases are considered, in the first with the regular mechanical constraints.
2017-07-10
Technical Paper
2017-28-1954
Premkumarr Santhanamm, K. Sreejith, Avinash Anandan
A local and global environmental concern regarding automotive emissions has led to optimize the design and development of Power train systems for IC engines. Blow-by and Engine oil consumption is an important source of hydrocarbon and particulate emissions in modern IC engines. Great efforts have been made by automotive manufacturers to minimize the impact of oil consumption and blow-by on in-cylinder engine emissions. This paper describes a case study of how simulation played a supportive role in improving piston ringpak assembly. The engine taken up for study is a six cylinder, turbocharged, water cooled diesel engine with a peak firing pressure of 140 bar and developing a power output of 227 KW at 1500 rpm. This paper reveals the influence of stepped land, top groove angle, ring face profile, twist features with regard to tweaking of Blow-by & LOC. Relevant design inputs of engine parameters were provided by the customer to firm up the boundary conditions.
2017-07-10
Technical Paper
2017-28-1925
Asif Basha Shaik Mohammad, Ravindran Vijayakumar, Nageshwar Rao Panduranga
Abstract The automotive market has seen a steady increase in customer demands for quiet and more comfortable tractors. High noise at Operator Ear Level (OEL) of tractor is the major cause of fatigue to the operator. With growing competition, and upcoming legislative requirement there is ominous need for the agricultural tractor manufacturers to control noise levels. The objective of this study is noise reduction on agricultural tractor by stiffening sheet metal components. The design and analysis plays a major role for determining the root cause for the problem. Once the problem and its root cause were well defined, the solution for addressing the problem would be made clear. The engine excitation frequency and Sheet metal Components such as fender and platform natural frequency were coming closer and are leading to resonance.
2017-06-27
WIP Standard
AMS6465E
This specification has been declared “NONCURRENT” by the Aerospace Materials Division, SAE, as of July 2009. It is recommended, therefore, that this specification not be specified for new designs. “NONCURRENT” refers to those specifications which have previously been widely used and which may be required for production or processing of existing designs in the future. The Aerospace Materials Division, however, does not recommend these specifications for future use in new designs. “NONCURRENT” specifications are available from SAE upon request.
CURRENT
2017-06-26
Standard
AS1010H
(A) Propose Revision To Figure 1 To Show Port #1 Is Per AS4377 Style "S" In Both Cases and General Update (B) Propose revision to add conductive high purity aluminum coating per MIL-DTL-83488 for aluminum alloy fittings. The W code aluminum parts with new finish will be distinguished by new finish code V at the end of part number.
CURRENT
2017-06-26
Standard
AMS4917J
This specification covers a titanium alloy in the form of sheet, strip, and plate through 4.000 inches (101.6 mm) nominal thickness.
2017-06-23
WIP Standard
D17AB
This revises the Identification section of the General Agreement on Marking.
CURRENT
2017-06-22
Standard
AMS5568H
This specification covers a corrosion and heat resistant steel in the form of welded tubing.
2017-06-22
WIP Standard
AMS2451/4D
This specification establishes the requirements for brush plating of cadmium by electrodeposition.
2017-06-22
WIP Standard
AMS2451/3C
This specification covers the requirements for brush plating of low-hardness, low-stress nickel by electrodeposition.
CURRENT
2017-06-22
Standard
AMS6512H
This specification covers a premium aircraft-quality, maraging alloy steel in the form of bars, forgings, mechanical tubing, flash welded rings up through 10.000 inches (254.00 mm) inclusive in diameter or least distance between parallel sides and stock for forging or flash welded rings.
CURRENT
2017-06-22
Standard
AS6414A
This specification is applicable to the processes that are used in the manufacture of aerospace elastomer parts utilizing materials conforming to AMS7XXX series specifications, user specifications, or print on a Purchase Order (PO) that calls out this document for aerospace applications. The elastomer parts are in the form of O-rings, plate seals and other compression seals.
CURRENT
2017-06-21
Standard
AMS4443H
This specification covers a magnesium alloy in the form of sand castings.
CURRENT
2017-06-21
Standard
AMS2249H
This specification defines limits of variation for determining acceptability of the composition of cast or wrought titanium and titanium alloy parts and material acquired from a producer.
CURRENT
2017-06-21
Standard
AS43021AR-3
No Scope available.
CURRENT
2017-06-21
Standard
AS43021-3
No Scope available.
2017-06-20
Article
All-new high energy B12 magnets from Bunting Magnetics Co.'s Magnet Applications, Inc. are a major upgrade to its neodymium compression bonded magnet product offerings.
CURRENT
2017-06-20
Standard
AIR4844C
The following terminology has been generated by the ATA/IATA/SAE Commercial Aircraft Composite Repair Committee (CACRC) and provides terminology for design, fabrication, and repair of composite and bonded metal structures. The purpose of this AIR is to provide terminology that should be used when developing CACRC repair documents or repair documents produced by airlines or airframe and engine manufacturers. It is intended to develop this AIR into an AS.
CURRENT
2017-06-20
Standard
AMS4315A
This specification covers an aluminum alloy in the form of sheet and plate up to 2.000 inch (54.80 mm) inclusive, in thickness (see 8.5).
CURRENT
2017-06-20
Standard
AS85848/1A
SCOPE IS UNAVAILABLE.
Viewing 1 to 30 of 38680

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