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Technical Paper
2014-10-13
S. Reifarth, V. Rajagopal, K. Gritzun, H.-E. Angstrom
The distribution of EGR between the cylinders of an internal combustion engine has been shown to have large impact on the engine emissions. Especially at high EGR, the combustion reacts sensibly to variations in the EGR-rate. A cylinder that receives excessive EGR produces soot particles while a cylinder with too little EGR has increased NOx-emission. It is therefore important to have knowledge about the mixing in an engine. This study compares two different EGR-mixing measurement methods. The first is based on CO2 measurement with standard probes, placed at 36 different locations in the intake manifold of the engine. The second method uses a laser beam and a detector to gain information about the mixing with a high time-resolution, placed at six positions of the intake manifold. Additionally, 1-D simulations are used to gain information about the mixing process. To vary the mixing process on the engine, two different air/EGR mixers are used and their mixing performance is evaluated.
Technical Paper
2014-10-13
Jianye Su, Min Xu, Peng Yin, Yi Gao, David Hung
Spark-ignition direct-injection (SIDI) gasoline engine, especially in downsized boosted engine platform, has proven to be one of the most promising concepts to improve vehicle fuel economy, and are increasing their market share relative to port fuel injection (PFI) engines in U.S., European and Chinese vehicles. However, higher particle number emission associated with operating the engine at higher loads provide additional challenges for meeting future stringent emission regulations. In this study, the potential of using multiple injection strategies (double injection and triple injection strategy during the intake stroke in homogeneous combustion mode) to reduce particle number emission was investigated using Horiba Mexa SPCS1000 in a 2.0 liter boosted SIDI gasoline engine at 1000 rpm, 11 bar BMEP condition. To clarify the mechanism for the particle emission benefit by multiple injection strategies, three-dimensional (3D) Computational Fluid Dynamics (CFD) model of the in-cylinder process was realized using CONVERGE software with the inputs from GT-Power® engine simulation.
Technical Paper
2014-10-13
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.
Technical Paper
2014-10-13
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].
Technical Paper
2014-10-13
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.
Technical Paper
2014-10-13
Jon Andersson, John May, Cecile Favre, Dirk Bosteels, Simon de Vries, Matthew Heaney, Matthew Keenan, Jonathon Mansell
The exhaust emissions of two Euro 6 diesel cars with different emissions control systems have been evaluated both on the road and over various chassis dynamometer test cycles. European emissions limits are currently set using the New European Driving Cycle (NEDC), but the European Commission is preparing additional test procedures to ensure that emissions are well controlled both in real use and over the legislative test cycle. The main focus of this work on ‘Real Driving Emissions’ (RDE) is on measurements using Portable Emissions Measurement Systems (PEMS) in real, on-road driving. A key focus of a test programme undertaken for AECC (the Association for Emissions Control by Catalyst) by Ricardo was therefore the use of PEMS systems to measure on-road emissions of both gaseous pollutants and particulate matter. This included measurement of particle number emissions with a new candidate system for this type of measurement. The results from this testing are compared with emissions measured over four different chassis dynamometer test cycles – the current legislative cycle (New European Driving Cycle, NEDC); the Common Artemis suite of test cycles (CADC) that is widely used in emissions modelling; the new Worldwide Light-duty Test Cycle (WLTC) defined by the UN Working Party on Pollution and Energy (GRPE) as part of the development of the Worldwide harmonised Light vehicles Test Procedure (WLTP); and a set of cycles produced by a Random Cycle Generator based on ‘short trip’ segments from the EU database used to construct WLTC.
Technical Paper
2014-10-13
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.
Technical Paper
2014-10-13
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.
Technical Paper
2014-10-01
Sermet Yucel, Melinda Moran Lucking, Jon Magnuson, Germana Paterlini, Benjamin Worel
Fuel economy and performance vary significantly with the vehicle design and configuration, road profile, and payload. The variation is more pronounced for heavy-duty trucks and understanding its origin is critical to maximizing fleet profitability. In this paper we demonstrate a method to continuously estimate fuel consumption breakdown over resistive forces while the vehicle is driven on a public highway. The method is fast, cost-effective, and capable of analyzing trip segments as short as one second. The method utilizes a non-linear Kalman filter and a vehicle dynamical model that has a coupled longitudinal and vertical motion. The paper presents the breakdown of fuel consumption and an estimate of road grade profile obtained by driving a heavy-duty vehicle at the MnROAD research facility in Albertville MN. The road grade profile of the high-volume segment on Westbound Interstate 94 and the fuel consumption breakdown of the MnROAD heavy-duty test truck were estimated from recorded Control Area Network (CAN) signals and known vehicle parameters.
Article
2014-09-30
The Model T261 series rotary transformer coupled torque sensors from SensorData Technologies meet the demanding in-line testing requirements of small motors, pumps, compressors, turbines, fans, and other fractional horsepower rated devices.
WIP Standard
2014-09-30
This SAE Aerospace Standard will cover airframe plain spherical bearings ustilizing a Copper Nickel Tin ball and a Corrosion Resistant Steel outer race for use between -65F and+350F.
Standard
2014-09-30
This document provides test performance requirements for air disc brake actuators for service and combination service parking brake actuators with respect to function, durability and environmental performance when tested according to SAE J2902.
WIP Standard
2014-09-30
This SAE Aerospace Information Report (AIR) examines the need for and the application of a power train usage metric that can be used to more accurately determine the TBO for helicopter transmissions. It provides a formula for the translation of the recorded torque history into mechanical usage. It provides examples of this process and recommends a way forward. This document of the SAE HM-1 IVHM Committee is not intended as a legal document and does not provide detailed implementation steps, but does address general implementation concerns and potential benefits.
WIP Standard
2014-09-30
The intent is to ballot this drawing package and then stabilize it.
WIP Standard
2014-09-30
This SAE Aerospace Standard will cover airframe plain spherical bearings ustilizing a Copper Nickel Tin ball and a Corrosion Resistant Steel outer race for use between -65F and+350F.
Technical Paper
2014-09-30
Mathialagan Balaji, Hemant Bhatkar, Jeya Kumar Ranjith Kumar, Ananthan Anbazhagan, Pramod Palkar
Abstract Rear axles are subjected to bending and torsion loads out of which Bending loads are predominant. In case of Off road vehicles Bi Axial- combination of Bending and torsion loads were predominant, because of axle construction and vehicle usage pattern. Defined test procedures are available for bending durability and torsional durability evaluation of axles. In this experiment, new test methodology was developed for Bi Axial durability evaluation of Off road vehicle rear axle with single servo hydraulic linear actuator. For creating Bi Axial load condition, we may need multiple actuators and complicated fixtures. Axle wheel end is constrained at an angle with suitable fixtures for creating the bending and torsional forces together in the axle. Servo hydraulic linear actuator with suitable loading arm is used for applying the test torque in the axle input flange. Vehicle parameters like Engine torque, wheel reaction, axle ratio and wheel static loaded radius (SLR) etc., used for arriving the test specification.
Technical Paper
2014-09-30
Britney J. McCoy, Arman Tanman
Abstract In-use testing of diesel emission control technologies is an integral component of EPA's verification program. Device manufacturers are required to complete in-use testing once 500 units have been sold. Additionally, EPA conducts test programs on randomly selected retrofit devices from installations completed with grants by the National Clean Diesel Campaign. In this test program, EPA identified and recovered a variety of retrofit devices, including diesel particulate filters (DPFs) and diesel oxidation catalysts (DOCs), installed on heavy-duty diesel vehicles (on-highway and nonroad). All of the devices were tested at Southwest Research Institute in San Antonio, Texas. This study's goal was to evaluate the durability, defined here as emissions performance as a function of time, of retrofit technologies aged in real-world applications. A variety of operating and emissions criteria were measured to characterize the overall performance of the retrofit devices on an engine dynamometer.
Technical Paper
2014-09-30
Shaoyun Sun, Yin-ping Chang, Qiang Fu, Jing Zhao, Long Ma, Shijie Fan, Bo Li, Andrea Shestopalov, Paul Stewart, Heinz Friz
Abstract In the development of an FAW SUV, one of the goals is to achieve a state of the art drag level. In order to achieve such an aggressive target, feedback from aerodynamics has to be included in the early stage of the design decision process. The aerodynamic performance evaluation and improvement is mostly based on CFD simulation in combination with some wind tunnel testing for verification of the simulation results. As a first step in this process, a fully detailed simulation model is built. The styling surface is combined with engine room and underbody detailed geometry from a similar size existing vehicle. From a detailed analysis of the flow field potential areas for improvement are identified and five design parameters for modifying overall shape features of the upper body are derived. In a second step, a response surface method involving design of experiments and adaptive sampling techniques are applied for characterizing the effects of the design changes. The characterization is followed by an optimization step to find the best possible drag improvement from these design changes.
Standard
2014-09-29
Applies to hydraulic seals used to seal the rods of hydraulic cylinders which are components of Off-Road Self-Propelled Work Machines defined in SAE J1116.
Technical Paper
2014-09-28
Abdulwahab A. Alnaqi, Suman Shrestha, David C. Barton, Peter C. Brooks
Abstract Aluminium alloys have been used extensively in the automotive industry to reduce the weight of a vehicle and improve fuel consumption which in turn leads to a reduction in engine emissions. The main aim of the current study is to replace the conventional cast iron rotor material with a lightweight alternative such as coated aluminium alloy. The main challenge has been to meet both the cost and functional demands of modern mass-produced automotive braking systems. A sensitivity analysis based on the Taguchi approach was carried out to investigate the effect of various parameters on the thermal performance of a typical candidate disc brake. Wrought aluminium disc brake rotors coated with alumina on the rubbing surfaces were determined to have the best potential for replacing the conventional cast iron rotor at reasonable cost. Optimisation of the structure was subsequently carried out using a genetic algorithm on the selected coated aluminium disc brake rotor. This determines the optimum thickness of the coating and the composition of the substrate based on selected criteria.
Technical Paper
2014-09-28
Bongkeun Choi
Abstract In this paper an effective technology of virtual thermal test of disc brake with several advanced analytic techniques was presented. With the virtual thermal test process, thermal performance of brake system could be easily evaluated without any possibility of great errors that used to happen in the past. In addition to the classical result of CFD, this virtual thermal test produced several valuable applications such as thermal deformation of rotor, optimization of thermal performance and estimation of braking distance.
Technical Paper
2014-09-28
Jaroslaw Grochowicz, Carlos Agudelo, Shanglei Li, Harald Abendroth, Karl-Heinz Wollenweber, Achim Reich
Abstract The efforts of the ISO “Test Variability Task Force” have been aimed at improving the understanding and at reducing brake dynamometer test variability during performance testing. In addition, dynamometer test results have been compared and correlated to vehicle testing. Even though there is already a vast amount of anecdotal evidence confirming the fact that different procedures generate different friction coefficients on the same brake corner, the availability of supporting data to the industry has been elusive up to this point. To overcome this issue, this paper focuses on assessing friction levels, friction coefficient sensitivity, and repeatability under ECE, GB, ISO, JASO, and SAE laboratory friction evaluation tests. With multiple companies (or programs) developing and assessing the friction coefficient and friction behavior under different methods, it is inevitable to avoid conflicts of performance requirements or lack of reproducibility or correlation of test results under different test methods.
Technical Paper
2014-09-28
Nils Perzborn, Carlos Agudelo, Georg Peter Ostermeyer
Abstract Inertia dynamometers are commonly used to determine the friction coefficient of brake assemblies. Dynamometers are a well-established platform, allow testing under controlled conditions, exhibit a good correlation to many situations encountered in real driving, and are comparatively economical and less time-consuming than full vehicle test. On the other side of the spectrum is the use of scaled tribometer. These test systems make possible a test without the entire brake corner. This separation allows the investigation of the frictional-contact only (frictional boundary layer) speedily and independently of a given brake system or vehicle configuration. As the two test systems (inertia dynamometers and tribometers) may have different users with possibly different tasks, the question remains regarding how comparable the two systems are. These issues provide incentives to better define the fields of investigations, correlation, and applicability for the two systems. In order to provide further insights and learning on this topic, this paper focuses on the measurement of the friction coefficient and the wear behavior using inertia dynamometer and scaled pin-on-disc tribometer testing.
Technical Paper
2014-09-28
Kenneth D. Norman, Amandeep Singh
Abstract Assessment of braking performance that includes brake fade is a critical part of the evaluation of military light tactical vehicles as it is for conventional light cars and trucks. These vehicles are sometimes called upon to operate in severe mountain regions that challenge the braking performance well beyond the environment in which these vehicles are normally operated. The U.S. Army Test Operating Procedure (TOP) 2-2-608 includes a test schedule conducted in the mountainous region near Jennerstown, Pennsylvania. While this test procedure represents a typical mountain environment, it does not represent the most severe mountain descents that can be encountered across the United States. As a preliminary step to developing a representative severe mountain descent braking test, mountain roads throughout the United States were evaluated analytically to identify potential test venues. A literature search was first undertaken to identify test procedures and test sites that were utilized by automobile manufacturers, independent automotive testing companies, U.S.
WIP Standard
2014-09-25
This test method outlines the standard procedure for measuring the radial and axial internal clearance of rolling element bearings used in airframe controls.
Article
2014-09-24
The use of quenched and tempered steels for dumper bodies reduces weight and fuel consumption while increasing payload capacity and wear life.
WIP Standard
2014-09-23
M22520/28 IS A CRIMPING TOOL, AIR POWER ACTUATED, FOR ELECTRICAL CONTACT WIRE BARREL SIZES 20 THROUGH 28.
WIP Standard
2014-09-23
BENCH MOUINT AND AIR PRESSURE FOOT VALVE FOR AS22520/28 AND AS22520/29 PNEUMATIC CRIMP TOOLS
WIP Standard
2014-09-23
M22520/29 IS A CRIMPING TOOL, AIR POWER ACTUATED, FOR ELECTRICAL CONTACT WIRE BARREL SIZES 12 THROUGH 20.
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