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AMS-STD-595A/10032

2016-05-01
AMS-STD-595A Color Chips Precise Color Matching, Individual Color Chips: A 3 x 5 inch color chip supplied in a 3 x 5 inch protective envelope for each AMS-STD-595 color, suitable for matching quality control inspection purposes. SAE Product Code: EA-10032 AMS-STD-595 – Colors Used in Government Procurement. This standard presents the colors used by Government Activities in a format suitable for color selection matching and for quality control inspection for paints and coatings. Standard is used with DoD and other Federal Agencies as a primary source of color reference.
Video

The New Audi A6/A7 Family - Aerodynamic Development of Different Body Types on One Platform

2011-11-17
The presentation describes the aerodynamic development and optimization process of the three different new models of the Audi A6/A7 family. The body types of these three models represent the three classic aerodynamic body types squareback, notchback and fastback. A short introduction of the flow structures of these different body types is given and their effect on the vehicle aerodynamic is described. In order to achieve good aerodynamic performance, the integration into the development process of the knowledge about these flow phenomena and the breakdown of the aerodynamic resistance into its components friction- and pressure drag as well as the induced drag is very important. The presentation illustrates how this is realized within the aerodynamic development process at Audi. It describes how the results of CFD simulations are combined with wind tunnel measurements and how the information about the different flow phenomena were used to achieve an aerodynamic improvement.
Video

High Speed Machining of CFRP Parts

2012-03-16
High Speed Machining of CFRP Parts Investigation of the influence of new geometries, cutting datas and coolant capabilities on the surface finish of CFRP parts. State of the art: Different CFRP grades and machining conditions make geometry adjustments to the tool necessary. Mechanical failures through machining operations can be avoided in most of the cases. New unidirectional CFRP grades and dry machining processes again lead to machining problems. This study investigates new geometries to avoid heat damage with dry maching and air coolant in case of unidirectional CFRP. With help of a thermo camera and the surface investigation with a scanning electron microscope, heat damage can be analysed and therefore new geometries can be developed and tested. Target is to develop a new multi purpose CFRP geometry to meet the requirements of the future. The reduction of different geometries used leads to major cost savings. Presenter Ingo von Puttkamer, Guhring oHG
Video

Tailored Conversion Coatings for Enhanced Adhesion to Metal

2012-03-21
As a result of recommendation from the Augustine Panel, the direction for Human Space Flight has been altered from the original plan referred to as Constellation. NASA's Human Exploration Framework Team (HEFT) proposes the use of a Shuttle Derived Heavy Lift Launch Vehicle (SDLV) and an Orion derived spacecraft (salvaged from Constellation) to support a new flexible direction for space exploration. The SDLV must be developed within an environment of a constrained budget and a preferred fast development schedule. Thus, it has been proposed to utilize existing assets from the Shuttle Program to speed development at a lower cost. These existing assets should not only include structures such as external tanks or solid rockets, but also the Flight Software which has traditionally been a ?long pole? in new development efforts. The avionics and software for the Space Shuttle was primarily developed in the 70's and considered state of the art for that time.
Video

PPG study reveals importance of color in vehicle purchase decisions

2021-03-20
PPG Industries, the world's leading manufacturer of transportation coatings, recently completed a study of consumer opinions regarding the importance of coatings and color as they relate to new car purchases. The goal of the study was to identify premium color consumers who place a large importance on vehicle color, what vehicles they purchase and how satisfied they are with the current color offerings. The internet based study consisted of approximately 1,340 U.S. consumers who have either purchased a new vehicle in the past two years, or are planning to purchase a vehicle within the next two years. Results from this study will be presented and those consumers identified by demographics. Presenter Michael Millar, PPG
Video

Using the Beer-Lambert Law and Kubelka-Munk Theory to Model Percent Transmittance of Multilayer Composite Coatings

2012-05-23
Transmission of light through automotive topcoat and primer layers can lead to degradation of the underlying electrocoat layer and to topcoat delamination. In order to protect against this, it is critical that transmission of both ultraviolet wavelengths and certain visible wavelengths be effectively blocked by the topcoat and primer layers. The clearcoat, basecoat and primer each have their own role and combine to protect against light transmission. The transmittance of these combined layers is typically measured by the Integrating Sphere UV-Visible Spectrophotometer. It would both simplify measurement of the topcoat systems and allow better system modeling if these layers could be measured separately and combined mathematically. We demonstrate here that absorbing and reflecting pigments can be effectively modeled using the Beer-Lambert law while results for scattering pigments are consistent with the Kubelka-Munk theory.
Video

5000 Hours Aging of THERBAN® (HNBR) Elastomers in an Aggressive Biodiesel Blend

2012-05-23
The need for light-weighting of automotive structures has spurred on a tremendous amount of interest in and development of low cost carbon fiber composite materials and manufacturing. This presentation provides a description of the commercial carbon fiber concept compared to traditional aerospace and specialty carbon fiber products. A specific update is presented on the development and commercialization of new low cost carbon fiber based on lignin / PAN precursor technology. The second focus of the presentation is on carbon fiber composite manufacturing processes, including carbon SMC, RTM, prepregs, and thermoplastic processes. Advantages and disadvantages of these processes are discussed, especially related to low cost manufacturing. Presenter George Husman, Zoltek Companies Inc.
Video

Development of Scratch Resistant Clear Coat for Automotive

2012-05-23
Scratch resistance is one of the most important customer requirements for automotive painting. Scratches occur as a result of a load being imposed on a paint film, which then destroys or deforms it. In order to improve the scratch resistance properties of clear coat, a specially developed molecular that act to accelerate closslinking reaction was added to the clear coat main resin. This developed molecular facilitates closslinking between multiple molecules and creates an unprecedentedly fine molecular structure. The result is a soft, highly elastic, and durable clear coat with improved resistance to light and acid as well as enhanced deformation recovery properties. It requires no special maintenance, prevents luster degradation caused by surface scratches and helps to prolong new-car color and gloss. Developmental Clear Coat is introduced into the flagship of the Lexus range - the LS as Self-restoring Coat in 2009. Presenter Junya Ogawa, Developmental Center
Video

Eco+ Solutions in High Performance Plastics from DSM for Automotive.

2012-05-22
In this paper we present the results of full-scale chassis dynamometer testing of two hybrid transit bus configurations, parallel and series and, in addition, quantify the impact of air conditioning. We also study the impact of using an electrically controlled cooling fan. The main trend that is noted, and perhaps expected, is that a significant fuel penalty is encountered during operation with air conditioning, ranging from 17-27% for the four buses considered. The testing shows that the series hybrid architecture is more efficient than the parallel hybrid in improving fuel economy during urban, low speed stop and go transit bus applications. In addition, smart cooling systems, such as the electrically controlled cooling fan can show a fuel economy benefit especially during high AC (or other increased engine load) conditions.
Video

Polycarbonate Glazing - Accelerated Wiper Testing, Surface Characterization and Comparison with On-Road Fleet Data

2012-05-23
Exatec� PC glazing technology team, has developed advanced weathering and abrasion resistant coatings technology that can be applied to protect polycarbonate. It is of particular interest to quantify and understand the factors that determine the surface abrasion performance of coated PC in rear window and backlight applications that have a wiper system. In the present study we describe Exatec's lab scale wiper testing equipment and test protocols. We also describe adaptation of optical imaging system to measure contrast and nano-profiling using nano-indenter, as post wiper surface characterization methods. These methods are more sensitive to fine scratches on glazing surface than standard haze measurement and mechanical profilometry. Three coating systems were investigated; Siloxane wetcoat (A), Siloxane wetcoat (B), and Siloxane wetcoat (B) plus plasma coat (Exatec� E900 coating). The performance comparisons were made using all these surface characterization methods.
Journal Article

Aerodynamic Characterization of a Full-Scale Compact Car Exposed to Transient Crosswind

2021-04-07
Abstract The transient surface pressure over a full-scale, operational compact automotive vehicle—a Volkswagen Golf 7—exposed to transient crosswinds with relative yaw angles of β = 22-45° has been characterized. Experiments were performed at the BMW side-wind facility in Aschheim, Germany. Measurements of the incoming flow in front of the car were taken with eleven five-hole dynamic pressure probes, and separately, time-resolved surface pressure measurements at 188 locations were performed. Unsteady characteristics (not able to be identified in quasi-steady modelling) have been identified: the flow in separated regions on the vehicle’s leeward side takes longer to develop than at the windward side, and spatially, the vehicle experiences local crosswind as it gradually enters the crosswind.
Journal Article

CFD and Wind Tunnel Analysis of the Drag on a Human-Powered Vehicle Designed for a Speed Record Attempt

2019-06-07
Abstract A computational fluid dynamics (CFD) and wind tunnel investigation of a human powered vehicle (HPV), designed by the Velo Racing Team at Ostfalia University, is undertaken to analyse the Eco-body’s drag efficiency. Aimed at competing in a high profile HPV speed record competition, the vehicle’s aerodynamic efficiency is shown to compare well with successful recent eco-body designs. Despite several limitations, newly obtained wind tunnel data shows that the corresponding CFD simulations offer an effective tool for analysing and refining the HPV design. It is shown that, in particular, the design of the rear wheel fairings, as well as the ride height of the vehicle, may be optimised further. In addition, refinements to the CFD and wind tunnel methodologies are recommended to help correlation.
Journal Article

Investigation of Passive Porosity as a Means for Bluff-Body Drag Reduction

2018-03-16
Abstract An investigation into the capability of passive porosity to reduce the drag of a bluff-body is presented. This initial work involves integrating varying degrees of porosity into the side and back faces of a small-scale model to determine optimum conditions for maximum drag reduction. Both force and pressure measurements at differing degrees of model yaw are presented, with the conditions for optimum performance, identified. At a length-based Reynolds number of 2.3 × 106, results showed a maximum drag reduction of 12% at zero yaw when the ratio of the open area on the back face relative to the side faces was between two and four. For all non-zero yaw angles tested, this ratio reduced to approximately two, with the drag benefit reducing to 6% at 10.5 degrees. From a supplementary theoretical analysis, calculated optimum bleed rate into the base for maximum drag reduction, also showed reasonable agreement to other results reported previously.
Journal Article

Microstructural Characterization and Hot Corrosion Behavior of Plasma-Sprayed Fe17Cr2Ni0.18C/Fly Ash Cenosphere-Based Composite Coating

2021-03-12
Abstract The current investigation studies the microstructure and high-temperature hot corrosion behavior of plasma-sprayed coatings. The composition of Fe17Cr2Ni0.18C and fly ash cenosphere powder is maintained in the 0%, 5%, 10%, and 15% ratio by weight percent, respectively. Both powder mixtures were thoroughly blended correspondingly and coated on T22 boiler steel tubings. Thermocyclic hot corrosion studies were examined in a liquid salt condition of Na2SO4—60% V2O5 for 17 cycles of 51 h at 600°C on bare and coated steels. Thermogravimetric practice was used to establish the kinetics of hot corrosion of uncoated and coated steels. As-coated samples are studied for microstructure and microhardness. X-ray diffraction (XRD), scanning electron microscopy (SEM)/energy-dispersive spectroscopy, and X-ray mapping characterization techniques have been utilized for structural analysis of the as-coated and hot-corroded samples.
Journal Article

Modeling of Temperature Swing Effect in Silica-Reinforced Porous Anodized Aluminum-Based Thermal Barrier Coating

2021-04-09
Abstract This article presents a finite element (FE)-based model to simulate the temperature swing phenomenon of Silica-Reinforced Porous Anodized Aluminum (SiRPA) thermal barrier coatings (TBCs). A realistic three-dimensional (3D) SiRPA coating microstructure is constructed based on the morphology of an experimentally grown coating structure, and the known relationship of geometry and anodization parameters. The coatings’ thermophysical properties are first computed using the FE model. The predicted thermal conductivity, thermal diffusivity, and bulk density are compared well with the experimental values. Also transient thermal analysis is conducted to model the temperature swing effect of the coating by comparing the temperature fluctuation of SiRPA coating with conventional Yttria-Stabilized Zirconia (YSZ)-based TBCs. With the predicted thermophysical properties, the model is capable to predict the “temperature swing” effect of SiRPA by transient thermal analysis.
Journal Article

Effect of Fuel-to-Air Ratio on Oxidation and Interfacial Structure in Galvanizing of a Dual-Phase Steel

2021-04-19
Abstract Automotive-grade high-strength steels are galvanized for improved corrosion resistance. However, selective oxidation of alloying elements during annealing heat-treatment may influence the subsequent zinc (Zn) coating quality. The formation of internal and external oxides depends on the alloy composition, especially the Si/Mn ratio, and the oxygen potential of the annealing atmosphere. In this work, a dual-phase (DP) steel was intercritically annealed with varied fuel-to-air ratios in a direct-fired furnace and then galvanized in a Zn bath with 0.2 wt% Al. The type of internal and external oxides and the interfacial structures between the steel substrate, the Al-Fe-Zn inhibition layer, and the Zn coating were examined by using site-specific focused ion beam (FIB) and transmission electron microscopy (TEM).
Journal Article

Design of High-Lift Airfoil for Formula Student Race Car

2018-12-05
Abstract A two-dimensional model of three elements, high-lift airfoil, was designed at a Reynolds number of ?????? using computational fluid dynamics (CFD) to generate downforce with good lift-to-drag efficiency for a formula student open-wheel race car basing on the nominal track speeds. The numerical solver uses the Reynolds-averaged Navier-Stokes (RANS) equation model coupled with the Langtry-Menter four-equation transition shear stress transport (SST) turbulence model. Such model adds two further equations to the ?? − ?? SST model resulting in an accurate prediction for the amount of flow separation due to adverse pressure gradient in low Reynolds number flow. The ?? − ?? SST model includes the transport effects into the eddy-viscosity formulation, whereas the two equations of transition momentum thickness Reynolds number and intermittency should further consider transition effects at low Reynolds number.
Journal Article

Influence of the Friction Coefficient in Self-Pierce Riveting Simulations: A Statistical Analysis

2018-05-08
Abstract In this work, optimal modeling parameters for self-pierce riveting (SPR) were determined using a factorial design of experiments (DOE). In particular, we show statistically how each of the calibrating parameters used in modeling the SPR process through nonlinear finite element modeling can drastically change the geometry of the joint. The results of this study indicate that the degree of interlock, which is a key feature of a sound joint, is largely influenced by the friction between the die and bottom sheet as well as the friction between the rivet and top sheet. Furthermore, this numerical study also helped elucidate the role of friction in SPR and sheds light on how coatings with diverse friction coefficients can affect material deformation and ultimately structural integrity of the joint.
Journal Article

Comparison of Various Drag Reduction Devices and Their Aerodynamic Effects on the DrivAer Model

2018-07-05
Abstract In this study, two types of drag reduction devices (a horizontal plate, and a vertical plate) are used to weaken the downwash of the upper flow and c-pillar vortex of the DrivAer notchback model driving at high speed (140 km/h). By analyzing and comparing 15 cases in total, the aerodynamic drag reduction mechanism can be used in the development of vehicles. First, various CFD simulation conditions of a baseline model were compared to determine the analysis condition that efficiently calculates the correct aerodynamic drag. The vertical plate and horizontal plate applied in the path of the c-pillar vortex and downwash suppressed vortex development and induced rapid dissipation. As a result, the application of a 50-mm wedge-shaped vertical plate to the trunk weakened the vortex and reduced the drag by 3.3% by preventing the side flow from entering the trunk top.
Journal Article

Parametric Study of Asymmetric Side Tapering in Constant Cross Wind Conditions

2018-06-28
Abstract Sports Utility Vehicles (SUVs) often have blunt rear end geometries for design and practicality, which is not typically aerodynamic. Drag can be reduced with a number of passive and active methods, which are generally prioritised at zero yaw, which is not entirely representative of the “on road” environment. As such, to combine a visually square geometry (at rest) with optimal drag reductions at non-zero yaw, an adaptive system that applies vertical side edge tapers independently is tested statically. A parametric study has been undertaken in Loughborough University’s Large Wind Tunnel with the ¼ scale Windsor Model. The aerodynamic effect of implementing asymmetric side tapering has been assessed for a range of yaw angles (0°, ±2.5°, ±5° and ±10°) on the force and moment coefficients.
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