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2016-04-05
Technical Paper
2016-01-1581
Felix Wittmeier, Armin Michelbach, Jochen Wiedemann, Victor Senft
With its recent wind tunnel upgrade, FKFS installed the first interchangeable 3-belt / 5-belt-system in a full scale automotive wind tunnel. With the 5-belt-system, which today is a state-of-the-art ground simulation technique, the system is ideally suited for day to day passenger car development work. The 5-belt system offers high flexibility, quick access to the underfloor and vehicle fixation, and setting the vehicle’s ride height by the restraint device. The first results of the 5-belt-system have already been presented in SAE 2015-01-1557. The 3-belt system on the other hand, offers a much more sophisticated ground simulation technique which is necessary especially for sports and racing cars. For such vehicles with low ground clearance, it is important to have a more accurate ground simulation, in order to capture the same aerodynamic modes of action and response as on the road.
2016-04-05
Technical Paper
2016-01-0478
Yinzhi He, Zhigang Yang, Yigang Wang
The full scale aeroacoustic wind tunnel of Shanghai Automotive Wind Tunnel Center (SAWTC) of Tongji University has been under full operation since 2009 after nearly 5 years construction and commissioning. This facility is designed with nozzle area 27m2 not only for full scale automobile testing of aerodynamics and aeroacoustics, but also for Buses, light trucks, scale train model etc. The maximal wind speed of this wind tunnel can reach 250km/h. One of the highlights is the extremely low background noise of only 61dBA at 160km/h. It is so quiet a wind tunnel first of all in China and contributes very much to the vehicle development of the vehicles marketed in the Chinese market. In this paper, after a short introduction about layout of the full scale aeroacoustic wind tunnel of Tongji University, the special acoustic measures to achieve so low background noise of this wind tunnel are presented as well.
2016-04-05
Technical Paper
2016-01-1607
David Soderblom, Per Elofsson, Ann Hyvärinen
The effect of blockage due to the presence of the wind tunnel walls has been known since the early days of wind tunnel testing. Today there are several blockage correction methods available for correcting the measured aerodynamic drag. However, due to the shape of the test object, test conditions and wind tunnel dimensions the effect on the flow may be different for two cab variants. This will result in a difference in the drag delta between so-called open-road conditions and the wind tunnel. Which makes it difficult to evaluate the performance of two different test objects when they are both tested in a wind tunnel and simulated in CFD. For example, the acceleration of the flow around the front corner radius will be enhanced in blocked test conditions, and in most correction methods these effects are not considered. In this study numerical simulations were performed in order to compare the blockage effects on several different cab shapes.
2016-04-05
Technical Paper
2016-01-1622
Miroslav Mokry
Lagally outlined his theory in the early 1920s, with no particular application in mind. Several decades later it became near indispensable in naval hydrodynamics, for calculating forces and moments exerted by the boundaries of narrow channels on passing vessels, effects of the ground or free surface on submerged bodies, etc. In wind tunnel testing, Lagally's theory has never really ‘caught on’. Assuming the model to be small relative to the test section, preference was given to the evaluation of the aerodynamic force increment from the ambient pressure gradient. However, as will be demonstrated in the paper, this approach is inaccurate for wind tunnel testing of larger blockage-ratio models even when their virtual masses can be established. The essence of the method presented here is as follows. By the Lagally theorem, the force exerted on a solid body by an external source is equal to the mass flow rate of the source times the induced velocity at the source location.
2016-04-05
Technical Paper
2016-01-0890
Richard Butcher
Measurement of lubricant related fuel economy with internal combustion [IC] engines presents technical challenges, though it does offer worthwhile insights into CO2 reduction. As engine technology progresses, large benefits become harder to find; so the importance of precise fuel economy measurement increases. Responding to the challenge of meeting CO2 targets, there are many successful areas of development currently for the IC engine; including downsizing/rightsizing, mechanical efficiency, advanced charging and combustion systems, thermal management, sophisticated electronic control and calibration. These technologies have been deployed against a back-drop of increasingly stringent criteria pollutant emission limits. The search for ever smaller improvements combined with growing engine and vehicle technology complexity significantly increases the challenge of producing high quality data.
2016-04-05
Journal Article
2016-01-1583
Brian R. McAuliffe, Alanna Wall, Guy Larose
During the past year, a novel turbulence generation system has been commissioned in the National Research Council (NRC) 9 m Wind Tunnel. This system, called the Road Turbulence System was developed to simulate with high fidelity the turbulence experienced by a heavy duty vehicle on the road at a geometrical scale of 30%. The turbulence characteristics that it can simulate were defined based on an extensive field measurement campaign on Canadian roads for various conditions (heavy and light traffic, topography, exposure) at heights above ground relevant not only for heavy duty vehicles but also for light duty vehicles. In an effort to improve continually the simulation of the road conditions for aerodynamic studies on a light duty vehicle, a study was carried out at NRC to define the applicability of the Road Turbulence System to aerodynamic testing of full-scale light duty vehicles.
2016-04-05
Journal Article
2016-01-1597
Christopher Collin, Steffen Mack, Thomas Indinger, Joerg Mueller
The open jet wind tunnel is a widespread test section configuration to develop full scale passenger cars in automotive industry. However, using a realizable nozzle cross section for cost effective aerodynamic development is always connected to certain wind tunnel effects. Wind tunnel wall interferences, which are not present under real road conditions, can affect the measurement of aerodynamic forces in a wind tunnel and cause the requirement to apply wind tunnel corrections. This work contains the results of a CFD approach, using unsteady DDES to determine the in terms of drag force optimal longitudinal position of a full scale car inside the open jet wind tunnel test section, at which interference effects between nozzle, open jet and car compensate each other. Hence, the optimal position for the selected car is proposed for – depending on the method used for dynamic pressure determination – plenum or nozzle method.
2016-04-05
Journal Article
2016-01-1595
Haibo Wu, Jiangbin Zhou, Qian Chen, Gongwen Liu, Chaoqun Qian
In this paper we present the work which was done at Shanghai-VW for using computational aero-acoustic (CAA) simulation in the vehicle development process to assess and improve the buffeting behavior of a vehicle when the rear side window is open. In the first step, a methodology was established and validated against wind tunnel tests using a Sedan. The methodology consists of a calibration of the CAA model to represent the properties of the cabin interior of the real car in terms of damping, wall compliance and leakage followed by CAA simulations of the full vehicle at different wind speeds to obtain the transient flow field around the exterior shape and inside the passenger compartment. The interior noise spectra are directly calculated from the transient pressure inside the cabin.
2016-04-05
Journal Article
2016-01-1614
Edward Duell, Amir Kharazi, Paul Nagle, Per Elofsson, David Söderblom, Christer Michael Ramden
Scania’s has opened a new climatic wind tunnel test facility, located at the Scania Technical Center in Södertälje, Sweden. This facility is designed for product development testing of heavy trucks and buses in a range of controllable environments. Having this unique test environment at the main development center enables Scania to test its vehicles in a controlled repeatable environment all year, improving lead times from design to production, producing higher quality and more reliable vehicles, and significantly improves capability for large vehicle performance research. This state-of-the-art facility provides environmental conditions from -35℃ to 50℃ with humidity control from 5 to 95 percent. The 13m2 nozzle wind tunnel can produce wind speeds up to 100 km/h. In addition to the ‘standard features’ listed above for a climatic wind tunnel, this facility includes several additional capabilities.
2016-02-05
Magazine
Off-highway hybrids: Opportunities and challenges With oil prices declining and emissions regulations in North America 'stabilized,' is there a place for hybrid powertrains in this new world of cheap oil? Looking for a better image Display advances are helping to reduce operator fatigue. Charging up electrified powertrains Control technologies race forward while batteries improve and adopt standard sizes. Measuring and accounting for suspension TARDEC teamed with SEA Ltd. to develop a system to measure the suspension parameters, center of gravity, and moments of inertia of wheeled vehicles in the never ending quest to model and predict vehicle dynamic behavior. Looking at mobility in 2050 Cuneyt L. Oge begins his term as 2016 SAE International President with a vision about the future of auto- and aero-mobility.
2016-02-03
Magazine
Baking in protection With vehicles joining the Internet of Things, connectivity is making cybersecurity a must-have obligation for automotive engineers, from initial designs through end-of-life. New Engines 2016 Highlighting the design, engineering, and technologies inside some of the most competitive new gasoline and light-duty diesel ICEs. Citizen of the world Cuneyt L. Oge begins his term as 2016 SAE International President with a vision about auto-mobility and aero-mobility 2050. CES rollouts extend connectivity, app integration Ford looks to spread Corning's new lightweight Gorilla Glass beyond the 2017 GT New 40%-scale wind tunnel increases GM's aero-development capacity Surface Generation speeds composites throughput with one-shot stamp-forming process 2017 Cadillac XT5 debuts GM's new lightweight crossover architecture Porsche and Bentley plan electric future
2015-12-18
WIP Standard
AIR6236A
This AIR provides guidance to the EMI test facility on how to check performance of the following types of EMI test equipment: Current probe Line Impedance Stabilization Network (LISN) Directional coupler Attenuator Cable loss Low noise preamplifier Rod antenna base Passive antennas All performance checks can be performed without software. A computer may be required to generate an electronic or hard copy of data. This is not to say that custom software might not be helpful; just that the procedures documented herein specifically eschew the necessity of automated operation.
2015-12-13
Standard
AIR6236
This AIR provides guidance to the EMI test facility on how to check performance of the following types of EMI test equipment: Current probe Line Impedance Stabilization Network (LISN) Directional coupler Attenuator Cable loss Low noise preamplifier Rod antenna base Passive antennas All performance checks can be performed without software. A computer may be required to generate an electronic or hard copy of data. This is not to say that custom software might not be helpful; just that the procedures documented herein specifically eschew the necessity of automated operation.
2015-12-01
Magazine
Uncertainty quantification The technique is a must for next-generation simulation tools. Oil-pump sizing Researchers from Hinduja Tech investigate options for low friction and power consumption. The future of Indian commercial aviation The growth in traffic that airport modernization has supported has also made a significant contribution to the local and national economies, while the improved infrastructure has been positive for the perception of India in the global market. Driving EVs toward lower cost The race ison to reduce battery and electric-drive systems cost while improving efficiency. Powering on Rolls-Royce's Chief Engineer discusses new technologies that inspire current R&D design and evaluation work as part of its strategic roadmap for future big commercial programs. HMIs extend beyond the cab Telematic functions are being integrated into multi-function user interfaces.
2015-10-13
WIP Standard
AIR5509A
This document defines the process steps involved in collecting and processing engine test data for use in understanding engine behavior. It describes the use of an aero-thermal cycle model for reduction and analysis of those data. The analysis process may include the calculation of modifiers to match the model to measured data, and prediction of engine performance based on that analysis
2015-09-25
Standard
AIR5320A
This SAE Aerospace Information Report (AIR) contains information on most of the major icing simulation ground facilities. An effort was made to obtain data from as many facilities as possible over a two year time period. The data in this document represents the state of the facilities in calendar year 1996. Facilities are constantly changing and upgrading and, therefore, some facility specifications may change during the life of this report. Of the 27 facilities described in this report, the primary use is split with approximately half for engine testing and half for wind tunnel testing. The facilities are limited to ground facilities and, therefore, icing tankers have not been included.
2015-09-15
Technical Paper
2015-01-2552
Helmut Plankl
Abstract The paper will start with a short introduction to the structure of the Airbus Group, before addressing the Airbus Defence and Space business line Military Aircraft. The Rig Operation department for airborne solutions within this organisation is responsible for the development, design, operation and support of ground test facilities and test support systems, which are used for design validation and verification of civil and military air systems. The main part of this document will start with a typical sequence of tests in our Test Centre. The presentation will then focus on some advanced methods used during the qualification of test equipment and to improve the efficiency of ground test facilities in terms of cost, time and risk reduction. The next topic is tool-based rig management and control, beginning with test preparation and test shift planning and also covering aspects of configuration control, automatisation of test facilities and support of the test report.
2015-09-15
Technical Paper
2015-01-2550
Kiran Thupakula
Abstract In Aerospace Industry, the major challenge is to meet the safety and quality of subsystem / system elements to comply with the standards defined by regulatory authorities for product certification. Engineering test labs are created to provide such precision oriented test platforms ranging from component level to fully integrated test labs/test systems, standalone or distributed network. Even after massive initial capital investment and with the evolution of technologies followed by principles of practice in establishing test facilities, industry is facing open challenges in meeting the performance parameters like productivity, optimum usage, accessibility, monitoring, control and ease of maintenance to list a few. It's very important to standardize the test facilities to optimize time to market and reduce the product cost.
2015-09-14
Standard
AIR5771
This report covers engine tests performed in Altitude Test Facilities (ATFs) with the primary purpose of determining steady state thrust at simulated altitude flight conditions as part of the in-flight thrust determination process. As such it is complementary to AIR1703 and AIR5450, published by the SAE E-33 Technical Committee. The gross thrust determined using such tests may be used to generate other thrust-related parameters that are frequently applied in the assessment of propulsion system performance. For example: net thrust, specific thrust, and exhaust nozzle coefficients. The report provides a general description of ATFs including all the major features. These are: Test cell air supply system. This controls the inlet pressure and includes flow straightening, humidity and temperature conditioning. Air inlet duct and slip joint. Note that the report only covers the case where the inlet duct is connected to the engine, not free jet testing.
2015-08-05
WIP Standard
AS4786B
This SAE Aerospace Standard (AS) covers variable speed, reversible battery powered drills with removable, rechargeable battery pack and either 3/8 inch or ½ inch chuck used for general maintenance and construction where a battery powered tool is required. This document also satisfies EMI requirements for driver drills, where EMI suppression is required by the purchaser. This document may involve hazardous materials, operations, or equipment and does not purport to address all of the safety considerations associated. It is the responsibility of the user of a piece of equipment to establish appropriate safety and health practices and to determine the applicability of regulatory limitations prior to its use. Users are cautioned to read all manufacturer’s instructions prior to use.
2015-06-15
Technical Paper
2015-01-2348
Richard Kolano
Abstract This paper presents the results of a study to reduce the background noise level within a large Quiet Room located adjacent to other laboratory testing environments and below a mechanical mezzanine which houses an extensive array of mechanical and electrical equipment including banks of low-temperature chiller compressors, air handling units, and electrical switchgear that serves the entire building complex. This equipment was installed atop the concrete mezzanine floor deck without provisions for isolating vibration. As a result, structure-borne noise from that equipment travels through the floor, radiates from the underside of the floor deck, and intrudes into the Quiet Room below. This causes the background noise level within the Quiet Room to be too high for conducting low sound level measurements and studies on vehicles brought into the Quiet Room.
2015-06-15
Technical Paper
2015-01-2346
Balakumar Swaminathan
Abstract From a facility perspective, engine test cells are rarely evaluated for their vibration levels in their functional configuration. When complicated dynamic systems such as an internal combustion engine and a dynamometer are coupled together using driveshafts and coupling components, the overall system behavior is significantly different from that of the individual sub-systems. This paper details an instance where system level experimental testing and finite element analysis methods were used to mitigate high vibration levels in an engine test cell. Modal and operational test data were taken to establish baseline vibration levels at a diesel engine test cell during commissioning. Measurements were taken on all major sub-systems such as the engine assembly, dynamometer assembly, intermediate driveshaft bearing pedestal and driveshaft components.
2015-06-15
Technical Paper
2015-01-2143
Christian Mendig
Abstract In the project SuLaDI (Supercooled Large Droplet Icing) research about the icing of aerofoils through large and super cooled droplets is done at the Institute of Composite Structures and Adaptive Systems (German Aerospace Center-DLR) and at the Institute of Adaptronics and Function Integration (Technische Universität Braunschweig). In the framework of the project an icing wind tunnel was built. It consists of a cooling chamber and a wind tunnel of the Eiffel-type therein. The icing of model takes place in the test section of the wind tunnel at temperatures below 0 °C. Between the flow straightener and the contraction section a spray system is built in, which sprays water droplets into the wind tunnel. The droplets are accelerated by the airstream and supercool on their way to the model. When hitting the model they freeze on it to rime ice, clear ice or mixed ice. At the model research about a structure integrated ice detection is done.
2015-06-15
Technical Paper
2015-01-2299
Dhanesh Purekar
Abstract NVH development of light duty diesel engines require significant collaboration with the OEM as compared to medium duty and heavy duty diesel engines. Typically, competitive benchmark studies and customer expectations define the NVH targets at the vehicle level and are subsequently cascaded down to the powertrain level. For engine manufacturing companies like Cummins Inc., it is imperative to work closely with OEM to deliver on the NVH expectations. In certain situations, engine level NVH targets needs to be demonstrated in the OEM or 3rd party acoustic test facility for customer satisfaction or commercial purposes. Engine noise tests across different noise test facilities may introduce some variation due to differences in the acoustic test facilities, test hardware, instrumentation differences, etc. In addition, the engine itself is a major source of variation.
2015-06-15
Technical Paper
2015-01-2116
Peter Struk, Tadas Bartkus, Jen-Ching Tsao, Tom Currie, Dan Fuleki
Abstract This paper presents measurements of ice accretion shape and surface temperature from ice-crystal icing experiments conducted jointly by the National Aeronautics and Space Administration (NASA) and the National Research Council (NRC) of Canada. The data comes from experiments performed at NRC's Research Altitude Test Facility (RATFac) in 2012. The measurements are intended to help develop models of the ice-crystal icing phenomenon associated with engine ice-crystal icing. Ice accretion tests were conducted using two different airfoil models (a NACA 0012 and wedge) at different velocities, temperatures, and pressures although only a limited set of permutations were tested. The wedge airfoil had several tests during which its surface was actively cooled. The ice accretion measurements included leading-edge thickness for both airfoils. The wedge and one case from the NACA 0012 model also included 2D cross-section profile shapes.
2015-06-15
Journal Article
2015-01-2154
Franck Hervy, Severine Maguis, François Virion, Biagio Esposito, Hugo Pervier
Abstract The A06 test facility designed for combustor testing in altitude has been modified to be converted in an icing facility for probe testing. The objective was to be able to simulate ice crystals conditions at high altitude, high Mach number and low temperature. This facility has been upgraded in several steps extending the median size of the ice crystals produced and the ice water content range. The aero-thermal and icing capabilities have been assessed during commissioning tests. Finally, in order to prepare the calibration of the facility, some measurement techniques for cloud characterization have been selected or developed, especially for cloud uniformity measurement.
2015-06-15
Journal Article
2015-01-2155
Tadas P. Bartkus, Peter Struk, Jen-Ching Tsao
Abstract This paper describes a numerical model that simulates the thermal interaction between ice particles, water droplets, and the flowing air applicable during icing wind tunnel tests where there is significant phase-change of the cloud. It has been previously observed that test conditions, most notably temperature and humidity, change when the icing cloud is activated. It is hypothesized that the ice particles and water droplets thermally interact with the flowing air causing the air temperature and humidity to change by the time it reaches the test section. Unlike previous models where the air and particles are uncoupled, this model attempts to explain the observed changes in test conditions by coupling the conservation of mass and energy equations. The model is compared to measurements taken during wind tunnel tests simulating ice-crystal and mixed-phase icing that relate to ice accretions within turbofan engines.
2015-06-15
Journal Article
2015-01-2156
Michael Oliver
Abstract The National Aeronautics and Space Administration (NASA) conducted a full scale ice crystal icing turbofan engine test using an obsolete Allied Signal ALF502-R5 engine in the Propulsion Systems Laboratory (PSL) at NASA Glenn Research Center. The test article used was the exact engine that experienced a loss of power event after the ingestion of ice crystals while operating at high altitude during a 1997 Honeywell flight test campaign investigating the turbofan engine ice crystal icing phenomena. The test plan included test points conducted at the known flight test campaign field event pressure altitude and at various pressure altitudes ranging from low to high throughout the engine operating envelope. The test article experienced a loss of power event at each of the altitudes tested.
2015-06-15
Technical Paper
2015-01-2347
James A. Mynderse, Alexander Sandstrom, Zhaohui Sun
Abstract The American Axle & Manufacturing Inc. driveline dynamometer provides immense value for experimental validation of product NVH performances. It has been intensively used to evaluate product design robustness in terms of build variations, mileage accumulation, and temperature sensitivity. The current driveline dynamometer input motor system has multiple torsional modes which create strong coupling with test part gear mesh dynamics. Mechanical Engineering seniors at Lawrence Technological University designed, fabricated, and validated a mechanism to decouple the driveline dynamics from the driveline dynamometer dynamics. The student-designed decoupler mechanism is presented with experimental validation of effectiveness in decoupling driveline dynamometer dynamics from the driveline under test.
2015-06-15
Journal Article
2015-01-2285
Arne Nykänen, David Lennström, Roger Johnsson
Abstract Subjects who are well aware of what to judge commonly yield more consistent results in laboratory listening tests. This awareness may be raised by explicit instructions and training. However, too explicit instructions or use of only trained subjects may direct experiment results in an undesired way. An alternative is to give fairly open instructions to untrained subjects, but give the subjects a chance to get familiar with the product and context by, for example, riding a representative car under representative driving conditions before entering the laboratory. In this study, sound quality assessments of interior sounds of cars made by two groups were compared. In one group subjects were exposed to the same driving conditions that were later assessed in a laboratory listening test by taking them on a ride in one of the cars to be assessed, just before entering the laboratory. In the other group subjects made the laboratory assessments without prior car riding.
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