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2015-09-14 ...
  • September 14-25, 2015 (6 Sessions) - Live Online
Training / Education Online Web Seminars
The Finite Element Analysis (FEA) has been widely implemented by automotive companies and is used by design engineers as a tool during the product development process. Design engineers analyze their own designs while they are still in the form of easily modifiable CAD models to allow for quick turnaround times and to ensure prompt implementation of analysis results in the design process.
2015-08-10 ...
  • August 10-12, 2015 (8:30 a.m. - 4:30 p.m.) - Troy, Michigan
  • December 9-11, 2015 (8:30 a.m. - 4:30 p.m.) - Troy, Michigan
Training / Education Classroom Seminars
RMS (Reliability-Maintainability-Safety-Supportability) engineering is emerging as the newest discipline in product development due to new credible, accurate, quantitative methods. Weibull Analysis is foremost among these new tools. New and advanced Weibull techniques are a significant improvement over the original Weibull approach. This workshop, originally developed by Dr. Bob Abernethy, presents special methods developed for these data problems, such as Weibayes, with actual case studies in addition to the latest techniques in SuperSMITH® Weibull for risk forecasts with renewal and optimal component replacement.
2015-06-25
Event
This session is dedicated to the tools and methodology involved in identifying, calculating and modifying various noise and vibration sources and paths in vehicles, aircraft and various consumer products and assist in the design and validation of noise and vibration targets
2015-06-24
Event
Frequency analysis is often referred to as Fourier analysis but is that really true? The foundation is based on stationary and "Fourier signals." What happens if that is not the case? Modern FFT signal analyzers use very sparse sampling that is correct according to Shannon but what will happen when using time domain analysis. Many of the myths and frequent questions will be answered using a "user perspective" and rules of thumb will be given together with good methods to avoid large errors. After attending this session, a much better understanding in regards to pitfalls and proper methodology will be the outcome.
2015-06-24
Event
This session provides a good overview of recent innovations to SEA modeling techniques. SEA models can be used alone or together with hybrid analytical or experimental techniques to establish good comparative NVH predictions at the earliest stage of the vehicle design process. The papers of this session will describe recent advances and / or validations of SEA theory, applications, or use in conjunction with hybrid techniques for high- and mid-frequency NVH predictions.
2015-06-24
Event
This session covers subjective testing and analysis related to automotive noise and vibration, usually referred to as sound quality and vibration quality. The focus is on both subjective and objective tools and methods that can be used either to design sound or vibration quality into the automotive product, or to characterize and eliminate undesired sounds or vibrations.
2015-06-24
Event
This session covers subjective testing and analysis related to automotive noise and vibration, usually referred to as sound quality and vibration quality. The focus is on both subjective and objective tools and methods that can be used either to design sound or vibration quality into the automotive product, or to characterize and eliminate undesired sounds or vibrations.
2015-06-23
Event
This session covers the relationships between vibration and noise that can be generated throughout the vehicle. Included in this session are modal vibration studies related to noise, vibration transfer paths throughout the vehicle, and coupling of vibration and acoustical modes. Both experimental and analytical approaches are included in this session.
2015-06-23
Event
This session covers the relationships between vibration and noise that can be generated throughout the vehicle. Included in this session are modal vibration studies related to noise, vibration transfer paths throughout the vehicle, and coupling of vibration and acoustical modes. Both experimental and analytical approaches are included in this session.
2015-06-15
Technical Paper
2015-01-2100
Yongsheng Lian, Yisen Guo
This paper investigated impingement of supercooled large droplets onto smooth solid surfaces to understand the mechanism of splashing and secondary droplets formation using a novel moment of fluid (MOF) method. Previous studies have established a splashing threshold, but the effect of ambient gas in liquid droplet splashing is not fully understood. Our numerical results of water droplet splashing with relatively low velocity were consistent with experimental results: splashing occurs at high pressure but not at low pressure. Our simulation revealed that a thin film was formed after the droplet contacted the solid surface. The thin film moved at a lower speed at the contact with the solid due to viscous effect while the film moved at a higher speed away from the solid. As a result, air was trapped under the film, making the film floating on the air. When the pressure was high, the air density was high hence the aerodynamic forces by the air on the thin film.
2015-06-15
Technical Paper
2015-01-2242
Ling Zheng, Zhanpeng Fang
The design optimization of interior noise in vehicle is addressed to reduce interior noise and improve customer satisfaction in this paper. The structural-acoustic model is established and the response of sound pressure in frequency domain is predicted by using finite element method. The minimization of sound pressure inside cabins depends on body structure and the thickness for each panel. The panel participation analysis is carried out to find out the key panels as design variables and improve the efficiency of optimization computation. Response Surface Method (RSM) is proposed and utilized to optimize the vibro-acoustic properties of body structure instead of complex structural-acoustic coupling finite element model. The accuracy of the proposed RSM is evaluated and discussed. Structural-acoustic problem is approximated by a series of quadratic polynomial using RSM. Geometric optimization problem of panels is described and solved to minimize the interior noise in vehicle.
2015-06-15
Technical Paper
2015-01-2244
Ulhas Dilipraj Mohite, Niket Bhatia, Prashant Bhavsar
Noise radiated from motorcycle engine is gaining significance not only to meet regulations but also to fulfil customer demands of quiet products. In IC engines, combustion pressure is one of the major excitations which is transmitted through powertrain to the casings and radiate noise. Early identification and correction of the casing critical areas contributing to noise will lead to substantial cost and development time reduction. In this paper the approach to predict engine noise under combustion forces is presented. This Methodology is divided into three stages: 1. Multi body dynamic (MBD) Simulation to determine excitation forces 2. Vibration analysis of engine under combustion load 3. Acoustic analysis of engine to predict Sound Pressure Level (SPL). Important parts of motorcycle engine with single cylinder are considered as flexible bodies for MBD simulation.
2015-06-15
Technical Paper
2015-01-2240
Gong Cheng, David W. Herrin
The theory of patch (or panel) contribution analysis is first reviewed and then applied to a motorcycle engine on a test stand. The approach is used to predict the sound pressure in the far field and the contribution from different engine components to the sound pressure at a point. First, the engine is divided into a number of patches. The transfer function between the sound pressure in the field and the volume velocity of a patch is determined by taking advantage of vibro-acoustic reciprocity. An inexpensive monopole source is placed at the receiver point and the sound pressure is measured at the center of each patch. With the engine idling, a P-U probe was used to measure particle velocity and sound intensity simultaneously on each patch. The contribution from each patch to the target point is the multiplication of the transfer function and the volume velocity, which can be calculated from particle velocity or sound intensity. There were two target points considered.
2015-06-15
Technical Paper
2015-01-2239
Nicholas N. Kim, Seungkyu Lee, J Stuart Bolton, Jon Alexander, Taewook Yoo, Sean Hollands
Because of the increasing concern with vehicle weight, there is an interest in lightweight materials that can serve several functions at once. Here we consider the vibration damping performance provided by an “acoustical” material (i.e., a fibrous layer that would normally be used for airborne noise control). First, earlier work related to the damping potential of fibrous, noise control materials is reviewed, and the primary damping mechanism is identified. It has been previously established that the vibration of panel structures creates a non-propagating nearfield in the region close to the panel. In that region, there is an oscillatory, incompressible fluid flow parallel to the panel whose strength decays exponentially with distance from the panel. When a fibrous medium is placed close to the panel in the region where the oscillatory nearfield motion is significant, energy is dissipated by the viscous interaction of the flow and the fibers, and hence the panel vibration is damped.
2015-06-15
Technical Paper
2015-01-2304
Hiroko Tada
In order to achieve a good balance between quietness in the vehicle interior cavity and lighter vehicle weight, it is necessary to study and optimize the specifications of the sound-proof packages. And, this optimization study is advisably done in the early stage of the vehicle development. For challenging to this antinomic, the process for improving automotive interior quietness (as related to air-borne noise above 400 Hz, considered the high-frequency range), with setting the marketability targets, the vehicle body acoustical performances and the parts specifications, was established. With conventional methods, it is challenging to disseminate the relationship between the overall vehicle performance and the performance of individual parts directly. Moreover, without new methods, it is also challenging to propose detailed specifications for the optimal sound-proof packages directly.
2015-06-15
Technical Paper
2015-01-2334
David Bogema, Gary Newton, Mark Stickler, Chris Hocking, Frank Syred
Realistically experiencing the sound and vibration data through actually listening to and feeling the data in a full-vehicle NVH simulator remarkably aids the understanding of the NVH phenomena and speeds up the decision-making process. In the case of idle vibration, the sound and vibration of the idle condition are perceived simultaneously, and both need to be accurately reproduced simultaneously in a simulated environment in order to be properly evaluated and understood. In this work, a case is examined in which a perceived idle quality of a vehicle is addressed. In this case, two very similar vehicles, with the same powertrain but somewhat different body structures, are compared. One has a lower subjective idle quality rating than the other, despite the vehicles being so similar.
2015-06-15
Technical Paper
2015-01-2338
Dong Guo, Quan Shi, Peng Yi
In-vehicle noise is composed of a variety of tonal (frequency-related) components and the tonal components play an important role in the improvement of interior vehicle sound quality. Much research has been focused on the suppression of sound pressure level and achieved certain positive effects. However, in some operating conditions, customers still perceive the tonal components and complain about the vehicle quality even the sound pressure level is relatively low. Therefore, a better understanding of how tonal components are perceived is necessary for automotive designers. To do so, psychoacoustics results about human hearing mechanism to tonal components are comprehensively summed in this study: human hearing response to pure tone, two tones and multiple tones. Then, well-controlled testing stimuli were generated and subjective annoyance testing was conducted. The results show agreement with former researchers’ findings.
2015-06-15
Technical Paper
2015-01-2243
Yang Liu, Pingjian Ming, Wenping Zhang, Xinyu Zhang
Turbocharger is an important part of the turbocharged diesel engine. Due to the increase of mass flow rate and pressure ratio the turbocharger, aerodynamic noise of turbocharger has become more apparent. And turbocharger noise becomes one of the major noise sources of the main engine system of the ship. In the paper, Based on Lighthill acoustic analogy theory, by using Computational fluid mechanics(CFD) and indirect boundary element method(IBEM), the aerodynamic noise prediction of marine turbocharger compressor is developed. On the basis of finite volume method, using the single stator and rotor blade passages, unsteady viscous flow in the centrifugal Compressor was simulated. The compressor’s flow characteristic was predicted and agree well with the experimental value. The flow field characteristics and frequency spectrum of the fluctuating pressure which agree well with the theoretical value were analysed.
2015-06-15
Technical Paper
2015-01-2302
Yuksel Gur, Jian Pan, David Wagner
Light weighting of vehicle panels enclosing vehicle cabin causes NVH degradation since engine, road, and wind noise acoustic sources propagate to the vehicle interior through these panels. In order to reduce this NVH degradation, there is a need to develop new sound package materials and designs for use in lightweight vehicles. In this paper, we will focus on the use of SEA (Statistical Energy Analysis Tool) as a CAE design tool to develop sound packages for use in lightweight vehicle design to recover NVH deficiencies due to sheet metal light weighting actions. Statistical Energy Analysis results for vehicle level as well as dash and floor subsystem levels will be presented and SEA prediction capability for the sound package development for vehicle design will be discussed.
2015-06-15
Technical Paper
2015-01-2301
Maxwell Hill, Dan Luo, Mark Moeller
Wind noise can be a significant event for automotive design engineers. The greenhouse glass plays an important role in the wind noise process. Robust estimates of the greenhouse glass damping are necessary for both understanding and modeling the role of the glass in the wind noise process. One unanswered question is whether the aerodynamic loads affect the window glass damping. To make this determination a method to assess the operational damping is required. The civil engineering community uses the random decrement technique to assess operational damping due wind loads. The random decrement technique has been shown to be a normalized autocorrelation function. In this paper the damping is estimated directly from the autocorrelation function. In the first section the relationship between the damping and autocorrelation function is examined for white noise excitation. A single oscillator is examined as the first case. Extension to higher modal densities is discussed.
2015-06-15
Technical Paper
2015-01-2336
Anastasios Arvanitis, Jeff Orzechowski, Todd Tousignant, Kiran Govindswamy
Automotive companies are looking into adding extra value to their vehicles by enhancing powertrain sound quality. The objective is to create a brand sound that is unique and preferred by their customers since quietness is not always the most desired characteristic, especially for high-performance products. This paper describes the process of developing a brand powertrain sound for a high-performance vehicle using the DFSS methodology. Initially the customer’s preferred sound was identified and analyzed. This was achieved by subjective evaluations through voice-of-customer clinics using vehicles of similar specifications. Objective data were acquired during several driving conditions. In order for the design process to be effective, it is very important to understand the relationship between subjective results and physical quantities of sound. Several sound quality metrics were calculated during the data analysis process.
2015-06-15
Technical Paper
2015-01-2110
Jozef Brzeczek, Janusz Pietruszka, Robert J. Flemming, Ben C. Bernstein
The PZL M28 05 airplane is an unpressurized twin-engine high-wing strut-braced monoplane of all-metal structure, with twin vertical tails and a tricycle non-retractable landing gear. It is certified to European Aviation Safety Agency (EASA) and Federal Aviation Administration (FAA) requirements. Airplane is certified to flight into known icing conditions in accordance with 14 CFR 23.1419 requirements, including flight in the icing conditions of Appendix C of 14 CFR 25. The PZL M28 05 airplane has characteristics that include short takeoff and landing (STOL) capability, high useful load, mission versatility and easy access through the rear cargo door. Depending on the equipment installed, the airplane can be operated with up to 19 passengers, as a cargo transport, in a mixed configuration, or in patrol version. The M28 is certificated in the Part 23 commuter category. The M28 05 maximum take off gross weight is 7500 kg (16534 lb) and the maximum operational airspeed (VMO) is 192 KIAS.
2015-06-15
Technical Paper
2015-01-2103
Christian Bartels, Julien Cliquet, Carlos Bautista
Icing is a phenomenon observed on aircraft airframes while flying through clouds of supercooled droplets. The phenomenon only occurs for ambient air temperatures below the freezing point. The droplets impinge on the aircraft surfaces and freeze, leading to ice accretion. The resulting change in aircraft geometry and surface roughness can modify the aircraft’s aerodynamic characteristics (lift loss, drag increase), it may affect air data probe measurements, and can even damage the engines by ice ingestion. In order to comply with certification regulations, airframers have to demonstrate safe operation of their aircraft in icing conditions. However, due to associated cost and time, it is prohibitive to cover the whole icing envelope by flight-testing or icing-tunnel testing. Therefore, aircraft manufacturers have developed, with support from research institutes, numerical prediction methods and tools to cover their prediction needs.
2015-06-15
Technical Paper
2015-01-2332
Jan Deleener, Akira Sekitou, Masanori OHTA
Shift feeling is an important comfort attribute for manual transmission driven vehicles. For front-wheel-drive vehicles, there are 3 main parts of interest: the gearbox, the shifter and the shift cable. Often only a test based evaluation process on the actual assembly is available in the later stages of development. In order to frontload the shift feeling evaluation a virtual simulation process is required. For the shift lever and the gearbox there are well established models available. With 3D multibody models or even 2D planar models the effect of kinematics and compliances like connection stiffness and friction are already studied today. However, the modelling of the transmission cable, connecting the gearbox and the shifter remains a challenge to accurately represent the physical feel. By experience it was known that the 3D positioning and curvature of the cable affected the friction force and therefore the shift feeling.
2015-06-15
Technical Paper
2015-01-2135
Martin Schulz, Michael Sinapius
A designer of a new mechanical ice protection system for airplanes needs to know how much and in which way he has to deform the surface to break off the ice. The ice adhesion strength is often used as design value. To measure the adhesive strength several methods have been published. This paper presents a review about those methods and discusses the way the adhesion strength is derived. Finite Element Method is used to give a good insight into the stress state at failure for different load cases. The implication of these illustrations is that equations which use only ultimate force and total interfacial area to calculate adhesion strength miss the local stress state at the crack tip and the complex process of crack growing. Hence the derived adhesion strength may not be comparable with others, because they depend in fact on neglected parameters like specimen size, substrate thickness and stiffness.
2015-06-15
Technical Paper
2015-01-2335
Scott Amman, Francois Charette, Paul Nicastri, John Huber, Brigitte richardson, Gint Puskorius, Yuksel Gur, Anthony Cooprider
Quantifying Hands-free Call Quality in an Automobile Hands-free phone use is the most utilized use case for vehicles equipped with infotainment systems with external microphones that support connection to phones and implement speech recognition. Critically then, achieving hands-free phone call quality in a vehicle is problematic due to the extremely noisy nature of the vehicle environment. Noise generated by wind, mechanical and structural, tire to road, passengers, engine/exhaust, HVAC air pressure and flow are all significant contributors and sources of noise. Other factors influencing the quality of the phone call include microphone placement, cabin acoustics, seat position of the talker, noise reduction of the hands-free system, etc. This paper describes the work done to develop procedures and metrics to quantify the effects that influence the hands-free phone call quality.
2015-06-15
Technical Paper
2015-01-2131
Colin Bidwell, David Rigby
A flow and ice particle trajectory analysis was performed for the booster of the Honeywell ALF502 engine. The analysis focused on two closely related conditions one of which produced an icing event and another which did not during testing of the ALF502 engine in the Propulsion Systems Lab (PSL) at NASA Glenn Research Center. The flow analysis was generated using the NASA Glenn GlennHT flow solver and the particle analysis was generated using the NASA Glenn LEWICE3D v3.61 ice accretion software. The inflow conditions for the two conditions were similar with the main difference being that the condition that produced the icing event was 6.8 K colder than the non-icing event case. The particle analysis, which considered sublimation, evaporation and phase change, was generated for a 5 micron ice particle with a sticky impact model and for a 24 micron, 7 bin ice particle distribution with an SLD splash model used to simulate ice particle breakup.
2015-06-15
Technical Paper
2015-01-2303
Katherine Tao, Alan Parrett, David Nielubowicz
The headliner system in a vehicle is an important element in vehicle noise control. In order to predict the performance of the headliner, it is necessary to develop an understanding of the substrate performance, the effect of air gaps, and the contribution from any acoustic pads in the system. Current Statistical Energy Analysis (SEA) models for predicting absorption performance of acoustic absorbers are based on material Biot properties. However, the resources for material Biot property testing are limited and cost is high. In this paper, modeling parameters for the headliner substrate are identified from a set of standard absorption measurements on substrates, using curve fitting and optimization techniques. The parameters are then used together with thickness/design information in a SEA model to predict the vehicle headliner system absorption performance.
2015-06-15
Technical Paper
2015-01-2084
Benedikt König, Ehab Fares, Andy P. Broeren
A new laser-scanning method was applied to capture the three-dimensional ice shapes created during ice-accretion test on a NACA 23012 airfoil conducted in the NASA Icing Research Tunnel. This facilitated the creation of high-fidelity digital surface representations of complex ice-shapes. Those digital shapes cannot only be used to create rapid-prototyping models for experimental simulations, but also serve as input for computational fluid dynamics (CFD) simulations. In the past, numerical simulations of iced airfoils and wings were typically based on simplified. But, independent of the complexity of the ice shape, current numerical methods often struggle with the complicated, highly unsteady separated flows occurring under iced conditions. In this work we present simulations based on the Lattice-Boltzmann methodology (LBM) and investigate it’s capability to simulate the flow around three-dimensional laser-scanned ice shapes.
2015-06-15
Technical Paper
2015-01-2237
Nickolas Vlahopoulos, Sergey Medyanik
Structural-Acoustic Joints for Incompatible Models in the Energy Finite Element Analysis Sergey Medyanik, Michigan Engineering Services, LLC Nickolas Vlahopoulos, University of Michigan In the EFEA method, the governing differential equations are formulated for an energy variable that has been spatially averaged over a wavelength and time averaged over a period. Differential equations are derived for all wave bearing domains within a system. Each differential equation represents a power balance over a control volume. The corresponding fundamental solutions vary exponentially with space, thus requiring only a small number of elements to capture numerically the smooth spatial variation. Joint matrices are required between the finite elements at locations where discontinuities in the primary EFEA variables exist.
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