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2014-10-20
Article
Meeting the cleanest emissions regulations ever with the phase-in of the Tier 4 Final and Stage IV imposed a new way to design and calibrate off-highway engines.
2014-10-20
Article
GP:50 Corporation LTD’s Model 188/288/388 miniature flush diaphragm pressure transducer series’ unique flush diaphragm design makes possible accurate pressure measurements of high-viscosity fluids, even within high shock and vibration environments, without port plugging and clogging.
2014-10-20
WIP Standard
ARP1821B
This SAE Aerospace Recommended Practice (ARP) includes recommendedground flotation analysis methods for both paved and unpaved airfields. The purpose of this document is to identify the recommended aircraft ground flotation analysis methods that should be used for aircraft landing gear design.
2014-10-17
Article
Supercritical Fluid Technologies’ bench top supercritical fluid extractor, the model SFT-110, provides an alternative to traditional extraction methods that use organic solvents.
2014-10-17
Article
W. L. Gore & Associates is expanding its family of high-speed data cables for the aerospace industry to meet the industry’s challenges to improve pilot communication and passenger in-flight entertainment while reducing downtime for maintenance and decreasing operating costs.
2014-10-17
Article
The OM-WLS-TEMP series wireless USB 2.0 full-speed temperature input module from Omega is fully compatible with both USB 1.1 and 2.0.
2014-10-17
Article
WITT-Gasetechnik’s dome-loaded pressure regulator is impervious to system pressure and withdrawal fluctuations.
2014-10-16
WIP Standard
J2302
This procedure measures the resistance to radiant heat flow of insulating materials in sleeve form. The sleeve's effectiveness (S{sub}E) is determined by measuring the difference in surface temperature of a flat black, single- diameter ceramic cylinder with and without the standard diameter sleeve at the specified temperature, position, and distance from the radiant heat source.
2014-10-13
Article
Researchers at VE Commercial Vehicles Ltd. in India employed downsizing to design a commercial vehicle exhaust system using the ANSYS CFD tool Fluent, resulting in a 14.1% reductions in both size and volume and a mass savings of 2%.
2014-10-13
Technical Paper
2014-01-2559
Christopher Bannister
Abstract When evaluating the performance of new boosting hardware, it is a challenge to isolate the heat transfer effects inherent within measured turbine and compressor efficiencies. This work documents the construction of a lumped mass turbocharger model in the MatLab Simulink environment capable of predicting turbine and compressor metal and gas outlet temperatures based on measured or simulated inlet conditions. A production turbocharger from a representative 2.2L common rail diesel engine was instrumented to enable accurate gas and wall temperature measurements to be recorded under a variety of engine operating conditions. Initially steady-state testing was undertaken across the engine speed and load range in order that empirical Reynolds-Nusselt heat transfer relationships could be derived and incorporated into the model. Steady state model predictions were validated against further experimental data. Model predictions for compressor wall temperature show very good correlation with measured data (average 0.4% error, standard deviation 1.27%) and turbine housing temperatures also demonstrate good agreement (average 2.7% error, standard deviation 3.58%).
2014-10-13
Technical Paper
2014-01-2558
Qiyou Deng, Richard Burke
Abstract Current turbocharger models are based on characteristic maps derived from experimental measurements taken under steady conditions on dedicated gas stand facility. Under these conditions heat transfer is ignored and consequently the predictive performances of the models are compromised, particularly under the part load and dynamic operating conditions that are representative of real powertrain operations. This paper proposes to apply a dynamic mathematical model that uses a polynomial structure, the Volterra Series, for the modelling of the turbocharger system. The model is calculated directly from measured performance data using an extended least squares regression. In this way, both compressor and turbine are modelled together based on data from dynamic experiments rather than steady flow data from a gas stand. The modelling approach has been applied to dynamic data taken from a physics based model, acting as a virtual test cell. Varying frequency sinusoidal signals were applied to the compressor and turbine pressure ratios and turbine inlet temperature to drive the physic model.
2014-10-13
Technical Paper
2014-01-2667
Ida Truedsson, William Cannella, Bengt Johansson, Martin Tuner
Abstract This study examines fuel auto-ignitability and shows a method for determining fuel performance for HCCI combustion by doing engine experiments. Previous methods proposed for characterizing HCCI fuel performance were assessed in this study and found not able to predict required compression ratio for HCCI auto-ignition (CRAI) at a set combustion phasing. The previous indices that were studied were the Octane Index (OI), developed by Kalghatgi, and the HCCI Index, developed by Shibata and Urushihara. Fuels with the same OI or HCCI Index were seen to correspond to a wide range of compression ratios in these experiments, so a new way to describe HCCI fuel performance was sought. The Lund-Chevron HCCI Number was developed, using fuel testing in a CFR engine just as for the indices for spark ignition (research octane number and motor octane number, RON and MON) and compression ignition (cetane number, CN). By running the engine in HCCI mode, the required compression ratio for achieving auto-ignition with a combustion phasing of CA50 3° after TDC was determined for various gasoline surrogate fuels prepared from blends of n-heptane, iso-octane, toluene, and ethanol.
2014-10-13
Technical Paper
2014-01-2840
Juan J. Hernández, Rosario Ballesteros, Javier Barba, José Guillén-Flores
Abstract In order to reduce the pollutant emissions (NOx and PM) of diesel engines, the addition of small gaseous fuel amounts or dual mode operation have been proved as potential techniques. This paper is focused on a detailed characterization of the particles emitted from a single cylinder diesel engine when part of the diesel fuel (5 to 20% by energy) is replaced by a gaseous fuel (producer gas, mainly composed by H2, CO, CH4 and inert compounds) coming from biomass steam gasification. The engine was run at constant speed and torque and different EGR rates. Particle samples were collected by means of fiber glass filters placed in a dilution mini-tunnel. Simultaneously, during tests, part of the exhaust gas was conducted to an SMPS to determine the particle size distribution. The filters were analyzed by using two different techniques: Thermogravimetric analysis (TGA) to obtain the volatile organic fraction (VOF) and the soot concentration, and Soxhlet extraction/High Performances Liquid Cromatography (HPLC) to speciate PAHs (Polycyclic Aromatic Hydrocarbons).
2014-10-13
Technical Paper
2014-01-2582
José Galindo, José Ramón Serrano, Pedro Piqueras, Javier Gómez
Abstract Calibration of internal combustion engines at different altitudes, above or below sea level, is important to improve engine performance and to reduce fuel consumption and emissions in these conditions. In this work, a flow test rig that reproduces altitude pressure variation is presented. The system stands out by its altitude range, compactness, portability and easy control. It is based on the use of turbomachinery to provide the target pressure to the engine intake and exhaust lines. The core of the system is composed of a variable geometry turbine (VGT) with a waste-gate (WG) and a mechanical compressor. Given a set of turbomachinery systems, the operation pressure and the air mass flow are controlled by the speed of the mechanical compressor and the VGT and WG position. A simple modification in the installation setup makes possible to change the operating mode from vacuum to overpressure. So that simulating altitude increase or decrease with the same flow test rig components.
2014-10-13
Technical Paper
2014-01-2664
Akira Iijima, Naoya Ito, Takashi Shimada, Masanori Yamada, Hideo Shoji
Abstract Knocking combustion experiments were conducted in this study using a test engine that allowed the entire bore area to be visualized. The purpose was to make clear the detailed characteristics of knocking combustion that occurs accompanied by cylinder pressure oscillations when a Homogeneous Charge Compression Ignition (HCCI) engine is operated at high loads. Knocking combustion was intentionally induced by varying the main combustion period and engine speed. Under such conditions, knocking in HCCI combustion was investigated in detail on the basis of cylinder pressure analysis, high-speed photography of the combustion flame and spectroscopic measurement of flame light emissions. The results revealed that locally occurring autoignition took place rapidly at multiple locations in the cylinder when knocking combustion occurred. In that process, the unburned end gas subsequently underwent even more rapid autoignition, giving rise to cylinder pressure oscillations. In addition, when the engine speed and main combustion period were varied, it was found that the intensity of the cylinder pressure oscillations, i.e., knocking intensity PKI, correlated strongly with the maximum pressure rise rate per unit time dP/dtmax [MPa/msec].
2014-10-13
Technical Paper
2014-01-2713
Jianyi Tian, Hongming Xu, Ramadhas Arumugam Sakunthalai, Dai Liu, Cheng Tan, Akbar Ghafourian
Abstract Engine transient operation has attracted a lot of attention from researchers due to its high frequency of occurrence during daily vehicle operation. More emissions are expected compared to steady state operating conditions as a result of the turbo-lag problem. Ambient temperature has significant influences on engine transients especially at engine start. The effects of ambient temperature on engine-out emissions under the New European Driving Cycle (NEDC) are investigated in this study. The transient engine scenarios were carried out on a modern 3.0 L, V6 turbocharged common rail diesel engine fuelled with winter diesel in a cold cell within the different ambient temperature ranging between +20 °C and −7 °C. The engine with fuel, coolant, combustion air and lubricating oil were soaked and maintained at the desired test temperatures during the transient scenarios. Instantaneous engine performances including torque and speed, gaseous emissions such as CO, THC and NOx, and particulate emissions for its number and mass are analyzed during each transient scenario under different ambient conditions.
2014-10-13
Technical Paper
2014-01-2637
Katsufumi Kondo, Junya Takahashi, Tetsuya Aizawa
Abstract Wall-deposition of soot particles occurs due to the interaction between spray flame and cylinder liner wall/piston surface, which can potentially affect soot morphology after the in-flame formation/oxidation processes and before the exit from engine cylinder. In order to investigate these effects, flame wall impingement was simulated in a constant volume combustion vessel and thermophoretic soot sampling was conducted for Transmission Electron Microscopic analysis. A TEM grid for the sampling was exposed to a single-shot diesel spray flame multiple times and the variation of soot morphology (concentration, primary particle diameter and aggregate gyration radius) among the multiple exposures was compared. Furthermore, a newly designed impingement-type sampler vertically exposed the grid to the spray flame and sampled soot particles under different boundary condition from that of conventionally used skim-type sampler. The morphology of soot particles sampled by the impingement- and skim-type samplers were compared.
2014-10-13
Technical Paper
2014-01-2642
Masaki Kuribayashi, Yuta Mizutani, Yutaro Ishizuka, Natsuki Taki, Tetsuya Aizawa
Abstract For better understanding of soot formation and oxidation processes in diesel combustion, effects of ambient oxygen concentration on in-flame diesel soot particle properties including concentration, size, number density and morphology were investigated in a constant volume combustion vessel via simultaneous LII (Laser-Induced Incandescence) / LS (Laser Scattering) imaging techniques and TEM (Transmission Electron Microscopy) analysis. An analysis of LII and LS images yielded 2-dimensional distribution images of concentration, size and number density of soot particles in diesel spray flame, based on a practical assumption that LII and LS signals are proportional to the soot particle size to the power of 3 and 6, respectively. The laser measurements and TEM analysis results of soot particles directly sampled in the diesel spray flame showed a consistent general trend that in the case of 21% ambient O2 concentration soot is formed earlier in the upstream region and disappears earlier due to faster oxidation, while in the case of 15% ambient O2 concentration, soot is formed later in more downstream region and disappears more slowly.
2014-10-13
Technical Paper
2014-01-2811
Michal Vojtisek-Lom, Martin Pechout, Michael Fenkl
Abstract The paper focuses on portable “on-board” instrumentation and methods for evaluation of exhaust emissions from scooters and various small machinery under real-world driving conditions. Two approaches are investigated here. In one, a miniature on-board system mounted on the equipment itself performs online measurements of the concentrations of the pollutants of interest (HC, CO, CO2, NOx, some property of particulate matter), and measurement or computation of the intake air flow. This approach has been used on a 50 cm3 scooter fitted with a 14-kg on-board system and driven on local routes. Measured concentrations of gaseous compounds, particle mass and total particle length were multiplied with the corresponding intake air flow computed from measured engine rpm, intake air manifold pressure and temperature. In the second approach, a full-flow dilution tunnel, gas analyzers and particle measurement or sampling devices are mounted on an accompanying hand cart or vehicle. This approach has been used with weedeaters, chainsaws, and lawnmowers.
2014-10-08
Standard
ARP6200
This SAE Aerospace Recommended Practice (ARP) describes the recommended tests and their associated test means for commercial aircraft hydraulic systems at the system level that are required to demonstrate compliance with the 14 CFR Part 25 and EASA CS 25 airworthiness regulations, and to show that the required level of maturity at the aircraft entry into service (EIS) has been achieved.
2014-10-08
Standard
AS5127/1C
This SAE Aerospace Standard (AS) describes test methods to determine the application and performance properties of two-component sealing compounds. It shall be used in conjunction with AS5127 and the applicable material specification. When modifications to these test methods are called out in material specifications, the material specification shall take precedence.
2014-10-06
WIP Standard
AS955A
This SAE Aerospace Standard (AS) covers high strength thin wall (commercial) metric sockets, universal metric sockets, metric box wrenches and metric torque adaptors which possess the strength, clearances, and internal wrenching design so configured that, when mated with 12 point fasteners conforming to the requirement of ISO 4095, they shall transmit torque to the fastener without bearing on the outer 5% of the fastener's wrenching points. This standard provides additional requirements beyond ASME B107.100 and B107.5M appropriate for aerospace use. Inclusion of dimensional data in this document is not intended to imply that all of the products described herein are stock production sizes. Consumers are requested to consult with manufacturers concerning lists of stock production sizes. The dimensional limits of box and combination wrench lengths have been established to provide configuration control for tool storage applications.
2014-10-06
WIP Standard
J2188
This SAE Recommended Practice takes into account modern standardized methods for collecting and summarizing data that has an effect on vehicle steady-state performance, such as engine output (gross and net), transmission losses, drivetrain efficiency, vehicle aerodynamic devices for various vehicle and body configurations, as well as road surface variations and air density variations resulting from altitude and barometric effects. The procedure does not address vehicle transient performance (acceleration, braking, and cornering), because of the considerable amount of additional data required such as moment of inertia of all the rotating parts. Nor does it address vehicles with torque converters and automatic transmissions. This document is, therefore, intended for vehicles having fixed-ratio type transmissions and positive engagement clutches. Metric and ISO unit conversions are provided in the metric conversion tables at the end of this procedure (see Appendix B). Some modern vehicles with electronic engine controls have the ability to vary the maximum engine revolutions for each gear, as well as permitting the power or rpm to increase if more time is spent in the lower gears, as when climbing a grade.
2014-10-06
Standard
AS9102B
This standard establishes the baseline requirements for performing and documenting FAI. Should there be a conflict between the requirements of this standard and applicable statutory or regulatory requirements, the applicable statutory or regulatory requirements shall take precedence.
2014-10-02
Article
The U. S Department of Transportation/NHTSA Vehicle Research and Test Center has commissioned dSPACE to supply an in-lab GPS simulation system. GPS simulation is used in the development and testing of numerous intelligent driving and traffic systems, including collision avoidance, advanced driver-assistance systems, navigation, and V2X communications.
2014-10-02
WIP Standard
AS23053/1
This detail specification establishes the requirements for a range of similar electrical insulating sleevings that will shrink to a predetermined size upon the application of heat.
2014-10-02
WIP Standard
AS23053/11
This detail specification establishes the requirements for a range of similar electrical insulating sleevings that will shrink to a predetermined size upon the application of heat.
2014-10-02
WIP Standard
AS23053/10
This detail specification establishes the requirements for a type of electrical insulating sleeving that will shrink to a predetermined size upon the application of heat.
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