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WIP Standard
2014-04-04
AS81511/17 will allow the conversion of the MIL-C-81511/17 to an AS specification.
WIP Standard
2014-04-04
AS81511/26 will allow the conversion of the MIL-C-81511/26 to an AS specification.
WIP Standard
2014-04-04
This SAE Aerospace Standard (AS) defines the requirements for polytetrafluoroethylene (PTFE) line, metallic reinforced, hose assemblies suitable for use in aerospace hydraulic, fuel and lubricating oil systems at temperatures between -67 °F and 450 °F for Class I assemblies, -67 °F and 275°F for Class II assemblies, and at nominal pressures up to 1500 psi. The hose assemblies are also suitable for use within the same temperature and pressure limitations in aerospace pneumatic systems where some gaseous diffusion through the wall of the PTFE liner can be tolerated.

The use of these hose assemblies in pneumatic storage systems is not recommended. In addition, installations in which the limits specified herein are exceeded, or in which the application is not covered specifically by this standard, for example oxygen, shall be subject to the approval of the procuring activity.

WIP Standard
2014-04-03
This AS provides a standard method for viscosity measurements of thickened (AMS 1428) anti-icing fluids.
Standard
2014-04-03
This method is designed to evaluate the coking propensity of synthetic ester-based aviation lubricants under two phase air-oil mist conditions as found in certain parts of a gas turbine engine, for instance, bearing chamber vent lines. Based on the results from round robin data in 2008-2009 from four laboratories, this method is currently intended to provide a comparison between lubricants as a research tool; it is not currently a satisfactory pass/fail test. At this juncture a reference oil may improve reproducibility (precision between laboratories); a formal precision statement will be given when there is satisfactory data and an agreed on, suitable reference oil if applicable.
Standard
2014-04-03
This specification provides dimensional standards for crimp type contact wire barrel design and is a replacement for MS3190. Some wire barrel designs may exist in AS39029 but are not considered approved for future use, therefore, will not appear in this specification. The crimp barrel sizes listed in this document have been standardized in AS39029 and AS22520 specifications, tools and contacts are available to support these listed sizes. These crimp barrel requirements shall be used for any contact, regardless of whether it is a standard or non-standard contact configuration. The specification lists details for three types of wire barrels: A, B, and C. Wire barrel type A is not recommended for new design. Table 4 lists each AS39029 detail sheet wire barrel type.
WIP Standard
2014-04-02
The Measurement of Coolant Hose task group conducted a round-robin study to determine the measuring capability of automotive suppliers and users to measure Inside Diameter (ID), Outside Diameter (OD), Wall Thickness (Wall) and wall thickness variation of hose using traditional measuring devices and techniques. Seven companies (five suppliers and two end users) participated in this testing. Based upon the round-robin study this information report will detail procedures, test measuring devices, results and recommendations.
WIP Standard
2014-04-02
This specification provides a standard set of procedures for sampling and testing to meet the requirements of material specifications for wrought titanium and titanium alloy products except forgings and forging stock. It is applicable to the extent specified in a material specification.
WIP Standard
2014-04-02
The Hose Measurement Task Force conducted a round-robin study to determine the measuring capability of automotive suppliers and users to simultaneously measure the Inside Diameter (ID), Outside Diameter (OD), Wall Thickness (Wall), and Wall thickness Variation (WV) of hose using a laser-based, non-contact LOTIS QC-20 gauging device. Three (3) companies (all end users) participated in this testing with one of the three companies performing the GR&R calculations presented herein. Based upon the round-robin study this report will detail procedures, test measuring devices, results, and conclusions.
Technical Paper
2014-04-01
Robert Golimbioschi, Giampiero Mastinu, Luca Cordioli, Massimiliano Gobbi, Davide Tagliabue, Giorgio Previati, Francesco Braga
Abstract A new electric powertrain and axle for light/medium trucks is presented. The indoor testing and the simulation of the dynamic behavior are performed. The powertrain and axle has been produced by Streparava and tested at the Laboratory for the Safety of Transport of the Politecnico di Milano. The tests were aimed at defining the multi-physics perfomance of the powertrain and axle (efficiency, acceleration and braking, temperature and NVH). The whole system for indoor tests was composed by the powertrain and axle (electric motor, driveline, suspensions, wheels) and by the test rig (drums, driveline and electric motor). The (driving) axle was positioned on a couple of drums, and the drums provided the proper torques to the wheels to reproduce acceleration and braking. Additionally a cleat fixed on one drum excited the vibration of the suspensions and allowed assessing NVH performance. The simulations were based on a special co-simulation between 1D-AMESIM and VIRTUAL.LAB. The contact between the wheels and the drums of the test rig were simulated by means of VIRTUAL.LAB.
Technical Paper
2014-04-01
Ping Zhong, Kang Zhang, Xu Chen, Yunlong Shi, Lianxiang Yang
Abstract The assembling accuracy of two contactors during the relay switch production is an important factor affecting the quality of relay. An embedded machine vision quality Inspection system has been developed for electric relay production line inspection. The proposed system can provide online feedback on the quality of the relays by measuring the distance of the gap between the contacts of them. Two CMOS imaging sensors are operated for image acquisition and the parallel working mode is realized under dual-channel mode. A red light illumination system has been adopted to eliminate the imaging noise from the reflection of the surfaces of copper sheet. Before the test, the features areas in the image of same type relay is selected as template and saved in the computer. During the inspection procedure, a rotation invariance detection scheme based on circular projection matching algorithm has been used for fast recognizing and locating detected object with the help of these feature areas.
Technical Paper
2014-04-01
Massimiliano Gobbi, Giampiero Mastinu, Giorgio Previati
A method for the measurement of the full mass properties of vehicles and subsystems is presented. The knowledge of the center of gravity location and of the inertia tensor of vehicles and subsystems is fundamental for performing accurate dynamic simulations, ranging from handling to durability. The accurate estimation of the inertia tensor can be achieved primarily via experimental tests. Given a rigid body and its mass, the proposed method allows to measure the center of mass location and the inertia tensor during a single test. The proposed technique is based on the analysis of the free motion of a multi-cable pendulum to which the vehicle or the subsystem is connected. The body under test is made rotating around three axes passing nearby the body center of mass with a highly non linear motion. The motion of the pendulum and the forces acting on the system are recorded and the mass properties are identified by means of a proper mathematical procedure based on a least square estimation.
Standard
2014-04-01
This SAE Recommended Practice provides the lighting function identification codes for use on all passenger vehicles, trucks, trailers, motorcycles, and emergency vehicles.
Technical Paper
2014-04-01
Kenji Tadakuma, Takashi Sugiyama, Kazuhiro Maeda, Masashi Iyota, Masahiro Ohta, Yoshinao Komatsu
A new wind tunnel was developed and adopted by Toyota Motor Corporation in March 2013. This wind tunnel is equipped with a 5-belt rolling road system with a platform balance that enables the flow simulation under the floor and around the tires in on-road conditions. It also minimizes the characteristic pulsation that occurs in wind tunnels to enable the evaluation of unsteady aerodynamic performance aspects. This paper describes the technology developed for this new wind tunnel and its performance verification results. In addition, after verifying the stand-alone performance of the wind tunnel, a vehicle was placed in the tunnel to verify the utility of the wind tunnel performance. Tests simulated flow fields around the vehicle in on-road conditions and confirmed that the wind tunnel is capable of evaluating unsteady flows.
Technical Paper
2014-04-01
Kevin R. Cooper, Miroslav Mokry
Abstract The solid-wall wind tunnel boundary correction method outlined in this paper is an efficient pressure-signature method that requires few wall-mounted pressures. These pressures are used to determine the strengths of model- and wake-representing singularities that are used with the method of images to calculate the longitudinal and lateral velocity increments induced by the wind tunnel walls. Two force correction models are presented that convert these velocity increments to force and moment corrections. The performances of the correction procedures are demonstrated by their application to data from two sets of four, geometrically identical, differently sized, simplified automotive models.
Technical Paper
2014-04-01
Daichi Katoh, Kensuke Koremoto, Munetsugu Kaneko, Yoshimitsu Hashizume
An air-dam spoiler is commonly used to reduce aerodynamic drag in production vehicles. However, it inexplicably tends to show different performances between wind tunnel and coast-down tests. Neither the reason nor the mechanism has been clarified. We previously reported that an air-dam spoiler contributed to a change in the wake structure behind a vehicle. In this study, to clarify the mechanism, we investigated the coefficient of aerodynamic drag CD reduction effect, wake structure, and underflow under different boundary layer conditions by conducting wind tunnel tests with a rolling road system and constant speed on-road tests. We found that the air-dam spoiler changed the wake structure by deceleration of the underflow under stationary floor conditions. Accordingly, the base pressure was recovered by approximately 30% and, the CD value reduction effect was approximately 10%. The ratio of the base pressure recovery to the CD value reduction effect was approximately 90%, suggesting that the main mechanism is the base pressure recovery produced by changing the wake structure.
Technical Paper
2014-04-01
Pierre-Olivier Santacreu, Laurent Faivre, Antoine Acher
Thermal fatigue of austenitic and ferritic stainless steel grades has been experimentally and numerically investigated. A special test has been developed to determine the thermal fatigue resistance of clamped V-shaped specimens. This test permits to impose thermal cycle by alternating resistance heating and air cooling. The thermal fatigue life of a specimen is expressed as the number of cycles to failure. For a given grade, the fatigue life depends on the maximal and minimal temperature of the cycle, holding time at the maximal temperature and specimen thickness. The advantage of this V-shape test is that it is a simple procedure quite representative of the thermal fatigue process occurring in an exhaust manifold. This test is well suited to perform a study of damage mechanisms and to compare stainless steel grades. Examination of the failed specimens indicated that cracks could be mainly attributed to out-of-phase (OP) thermal fatigue process especially in case of ferritic grades. For austenitic steels (AISI304 EN1.4301, AISI321 EN1.4541 or AISI308 EN1.4828) at a critical temperature or above, an in-phase (IP) thermal fatigue mechanism is coupled with oxidation and creep, which are further significantly reducing the lifetime.
Technical Paper
2014-04-01
Gerhard Wickern
Abstract Open jet wind tunnels are normally tuned to measure “correct” results without any modifications to the raw data. This is an important difference to closed wall wind tunnels, which usually require wind tunnel corrections. The tuning of open jet facilities is typically done experimentally using pilot tunnels and adding final adjustments in the commissioning phase of the full scale tunnel. This approach lacked theoretical background in the past. There is still a common belief outside the small group of people designing and using open jet wind tunnels, that - similar to closed wind tunnels, which generally measure too high aerodynamic forces and moments without correction - open jet wind tunnels measure coefficient too low compared to the real world. The paper will try to show that there is a solid physical foundation underlying the experimental approach and that the expectation to receive self-correcting behavior can be supported by theoretical models. During the past years an improved understanding of test section interference in open jet wind tunnels has been developed.
Technical Paper
2014-04-01
Oliver Mankowski, David Sims-Williams, Robert Dominy
This paper outlines the creation of a facility for simulating on-road transients in a model scale, ¾ open jet, wind tunnel. Aerodynamic transients experienced on-road can be important in relation to a number of attributes including vehicle handling and aeroacoustics. The objective is to develop vehicles which are robust to the range of conditions that they will experience. In general it is cross wind transients that are of greatest significance for road vehicles. On-road transients include a range of length scales but the most important scales are in the in the 2-20 vehicle length range where there are significant levels of unsteadiness experienced, the admittance is likely to be high, and the reduced frequencies are in a band where a dynamic test is required to correctly determine vehicle response. Based on measurements of on-road conditions, the aim was for the turbulence generation system to achieve yaw angles up to 6-8°, equating to a lateral turbulence intensity of 8-10% with a frequency range extending up to 10 Hz.
Technical Paper
2014-04-01
Dirk Wieser, Hanns-Joachim Schmidt, Stefan Müller, Christoph Strangfeld, Christian Nayeri, Christian Paschereit
The experimental investigation was conducted with a 25%-scaled realistic car model called “DrivAer” mounted in a wind tunnel. This model includes geometric elements of a BMW 3 series and an Audi A4, accommodating modular, rear-end geometries so that it represents a generalized modern production car. The measurements were done with two different DrivAer rear end configurations (fastback and notchback) at varying side-wind conditions and a Reynolds number of up to Re=3.2·106. An array of more than 300 pressure ports distributed over the entire rear section measured the temporal pressure distribution. Additionally, extensive flow visualizations were conducted. The combination of flow visualization, and spatially and temporally resolved surface pressure measurements enables a deep insight into the flow field characteristics and underlying mechanisms. Moreover, static pressure fluctuations indicate regions with a high turbulence level due to flow separation and interaction between different vortical structures.
Technical Paper
2014-04-01
Sofie Koitrand, Lennart Lofdahl, Sven Rehnberg, Adrian Gaylard
Automotive aerodynamics measurements and simulations now routinely use a moving ground and rotating wheels (MVG&RW), which is more representative of on-road conditions than the fixed ground-fixed wheel (FG&FW) alternative. This can be understood as a combination of three elements: (a) moving ground (MVG), (b) rotating front wheels (RWF) and (c) rotating rear wheels (RWR). The interaction of these elements with the flow field has been explored to date by mainly experimental means. This paper presents a mainly computational (CFD) investigation of the effect of RWF and RWR, in combination with MVG, on the flow field around a saloon vehicle. The influence of MVG&RW is presented both in terms of a combined change from a FG&FW baseline and the incremental effects seen by the addition of each element separately. For this vehicle, noticeable decrease in both drag and rear lift is shown when adding MVG&RW, whereas front lift shows little change. The same trends are seen in both CFD and experimental data.
Technical Paper
2014-04-01
Austin Hausmann, Christopher Depcik
This study investigates the practicality of vehicle coast down testing as a suitable replacement to moving floor wind tunnel experimentation. The recent implementation of full-scale moving floor wind tunnels is forcing a re-estimation of previous coefficient of drag determinations. Moreover, these wind tunnels are relatively expensive to build and operate and may not capture concepts such as linear and quadratic velocity dependency along with the influence of tire pressure on rolling resistance. As a result, the method elucidated here improves the accuracy of the fundamental vehicle modeling equations while remaining relatively affordable. The trends produced by incorporating on road test data into the model fit the values indicated by laboratory tests. This research chose equipment based on a balance between affordability and accuracy while illustrating that higher resolution frequency equipment would further enhance the model accuracy.
Technical Paper
2014-04-01
Bryan Randles, Daniel Voss, Isaac Ikram, Christopher Furbish, Judson Welcher, Thomas Szabo
Determination of vehicle speed at the time of impact is frequently an important factor in accident reconstruction. In many cases some evidence may indicate that the brake pedal of a striking vehicle was disengaged, and the vehicle was permitted to idle forward prior to impacting the target vehicle. This study was undertaken to analyze the kinematic response of various vehicles equipped with automatic transmissions while idling, with the transmissions in drive and the brake pedals disengaged. An array of sedans, SUV's and pickup trucks were tested under 3 roadway conditions (flat, medium slope and high slope). The vehicle responses are reported and mathematical relationships were developed to model the idle velocity profiles for flat and sloped roadway surfaces.
Viewing 31 to 60 of 22277

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