Browse Topic: Windows and windshields

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Development of Higher Clarity Injection Molded Windscreen for Motorcycles2024-32-004004/18/2025
The windscreen is one of the key elements to enhance passenger comfort of touring motorcycle. The clarity through the windscreen should not discomfort the rider. The discomfort we discuss here mainly refers to three factors: the “distortion,” the “blur,” and the “transparency.” Introduced in this paper is the technical measures to achieve sufficient clarity by the injection molding method. Firstly, with respect to the “distortion,” we determined the main cause was local unevenness of plate thickness. As the uneven thickness were related to the accuracy of the die, we clarified the tolerable zone and carried out higher precision machining of the die to satisfy the requirements. Regarding the “blur,” we analyzed the refractive power of the windscreen and found the main cause of blur is the microscopic roughness on the surface. As the microscopic roughness were attributable to the die surface, we clarified the tolerable zone and established the polishing conditions satisfactory for the
Yamada, Atsushi, Endo, Sakae
SAE TOMORROW TODAY: Launching Human Space Travel with a Luxury Balloon1349801/23/2025
Imagine a six-hour journey to outer space that includes a world-class meal, cocktail service, Wi-Fi, and unprecedented views of Earth. This experience could soon become reality. Space Perspective, the world's first carbon-neutral spaceflight experience company, is commercializing space travel with Spaceship Neptune, a pressurized capsule propelled by a giant SpaceBalloon(TM). The experience is designed to be gentle and accessible with no rockets, weightlessness, heavy g-forces, or training required. Alongside world-class meal and cocktail service, space travelers will also enjoy views through the largest windows ever flown to space, Wi-Fi, and a proper restroom. To learn more, we sat down with Taber MacCallum, Founder and Chief Technology Officer, Space Perspective, to discuss the technical development of the SpaceBalloon(TM) and how the company is unlocking the market for space travel in a new and innovative way. We'd love to hear from you. Share your comments, questions and ideas for
Hineman, Marcie
Aircraft Cockpit Window Improvements Enabled by High-Strength Tempered Glass01-17-02-001201/25/2024
This research was initiated with the goal of developing a significantly stronger aircraft transparency design that would reduce transparency failures from bird strikes. The objective of this research is to demonstrate the fact that incorporating high-strength tempered glass into cockpit window constructions for commercial aircraft can produce enhanced safety protection from bird strikes and weight savings. Thermal glass tempering technology was developed that advances the state of the art for high-strength tempered glass, producing 28 to 36% higher tempered strength.As part of this research, glass probability of failure prediction methodology was introduced for determining the performance of transparencies from simulated bird impact loading. Data used in the failure calculation include the total performance strength of highly tempered glass derived from the basic strength of the glass, the temper level, the time duration of the load, and the area under load.A high-strength transparency
Lampman, DeWitt
Intelligent Voltaic Tinting of Automobile Glasses Obeying Regional Restraints2022-01-011103/29/2022
The contemporary automotive industry demands unceasing and sustained introduction and improvement of intelligent attributes in today’s machines. Like every other sector in the industry, we want our daily ride to do a handful of things by itself in today’s world. Glass shading has been in play for a long time in the automotive industry. From installing tinted films of a darker shade on the vehicle windows, we have come a long way where today we are able to place smart window tints on our car. These can tint themselves automatically as per the lighting condition when set in the autonomous mode. We also get a bunch of manual controls to control the shade levels as per our requirement or convenience. Now each region has its own tinting laws and it’s inevitable we adhere to them to save ourselves from getting booked by law enforcement. Therefore, the demand arises to make our smart tinting system smarter, so that it can recognize the place the automobile is driving by and adjust the maximum
Padinhare Kandi Meethal, Shameer, Moni, Ayan
Zebra Printer in-line Implementation2021-36-006402/04/2022
The project presents the advantages of using agile methodologies such as Scrum and Extreme Programing, for software development inside big company, showing that is feasible to adopt Agile Methods even in large companies’ culture. Analyzing this methodology being applied in a print management software for a zebra printer, demonstrating the characteristics of agile development such as agility in development time and ease of adapting the necessary changes in a Windows forms application with the C language. The application that was used to demonstrate the advantages of these methodologies has three basic functions, managing communication with an external service to validate and pass printer status, which is done through an RS232 communication, information management in database SQLite in the application itself, and control of the information that will be sent to a zebra printer, through an Ethernet communication passing data in ZPL (Zebra Programming Language). The advantages of applying
Oliveira, Lucas Miranda, dos Santos Nunes, Caio C´esar, da Costa, Roberto Coelho
Performance Evaluation of Eastman’s Saflex® E Series Acoustic Interlayer2021-01-105408/31/2021
In 2020, Eastman launched a new acoustic PVB interlayer for automotive laminated glass. This interlayer not only helps to protect driver and passengers from injuries during impact but also provides enhanced acoustic comfort in the car. This newly developed interlayer offers substantially improved acoustic performance in the high-frequency range that is typically associated with wind noise at higher vehicle speeds. To demonstrate the in-vehicle performance, finite element simulations have been carried out using wind noise as the principal source of excitation. The results confirm previously published data that the acoustic contribution overwhelms the turbulent part, having a larger contribution to the ultimate acoustical pressure level. The acoustic insulation calculated is in excellent agreement with the static sound transmission loss data as measured according to the ISO or ASTM norm. In cases where both the windscreen and front-side windows have a laminated structure, a large
D'Haene, Pol, Van de Vyver, Stijn, Poulos, Athanasios, Robin, Xavier
Windshield with Enhanced Infrared Reflectivity Enables Packaging a Driver Monitor System in a Head-Up Display2021-01-010504/06/2021
Integration of a driver monitor system (DMS) in a head-up display (HUD) gives the monitor camera a continuous view of the driver’s face, since the driver always faces the road ahead. However, with both infrared (IR) illuminator and IR camera packaged in the HUD, reflectivity of the windshield is important at IR wavelengths used by the camera. Not only is windshield IR reflectivity important for a clear camera image of the driver’s face, but increasing windshield reflectivity also decreases the effect of ambient sunlight on the camera image of the driver’s face. We describe a method to measure windshield reflectivity, both for the 940 nm band used by a DMS, and for visible light for the HUD. The measurement method uses a fiber-optic spectrometer, two collimating lenses, and a method to compensate for sample tilt. The lenses are mounted on a stage that adjusts the height above the sample. As an example, this method was used to characterize an IR reflecting windshield, prepared for a
Lambert, David K., Itsede, Fidelis, Tomura, Kazuhiro, Nohara, Atsushi, Chou, Kinryo, Carty, Dylan
Atomically Thin Light-Emitting Device for Invisible DisplaysTBMG-3820812/01/2020
A bright-light-emitting device that is millimeters wide and fully transparent was developed. The light-emitting material in this device is a monolayer semiconductor that is three atoms thick, allowing it to conform to curved surfaces.
Study of the Noise Contributors on the Interior Acoustic of a Car and Their Countermeasures2020-01-158506/03/2020
This paper shows that the collaboration between a glass manufacturer and a passive acoustic treatment manufacturer can bring different benefits and considerably improve the interior acoustics of a vehicle. In terms of passenger safety and well-being, glazing have always played a key role by offering solutions to interior comfort, particularly when it comes to heat and acoustics. Today, cars are becoming a living space which from an acoustic point of view brings a challenge for the interior comfort. Indeed, glazing has no absorption and classically it has an acoustic insulation weakness around its coincident frequency. In most of the cases, these different aspects make glazing one of the main contributors to the sound pressure level in the passenger compartment, and the trend is not one of change. However, there are possible countermeasures. One of which is the use of laminated glazing with acoustic PVB. This solution allows to reduce the loss of insulation performance at the
Lafont, Thibault, Dalzin, Fabien, Bouillet, Fabien, Bertolini, Claudio
CFD Analysis and Validation of Automotive Windshield De-Fogging Simulation2020-28-003904/30/2020
Nowadays Climate component system plays a vital role in JD power rating of automotive vehicle. Apart from customer point of view, stringent homologation norms pose challenge in designing climate control system components. At extreme cold climate conditions either mist/ fog forms on the automobile windshield. This makes visibility issue on driver/Co driver side. To overcome this issue efficient demister system is required. Development of Demister system requires thorough knowledge on velocity spread over windscreen and thermal performance of heater (HVAC). This work is aimed for simulating windshield demisting patterns of a vehicle as described by ECC norms. New methodology was developed to simulate the actual behaviour of condensation and evaporation of mist on the windscreen. Transient demisting patterns were simulated with the CFD code and validated with experimental test results.
Sathianarayanan, Gopinath
Vehicle Velocity Prediction Using Artificial Neural Network and Effect of Real World Signals on Prediction Window2020-01-072904/14/2020
Prediction of vehicle velocity is important since it can realize improvements in the fuel economy/energy efficiency, drivability, and safety. Velocity prediction has been addressed in many publications. Several references considered deterministic and stochastic approaches such as Markov chain, autoregressive models, and artificial neural networks. There are numerous new sensor and signal technologies like vehicle-to-vehicle and vehicle-to-infrastructure communication that can be used to obtain inclusive datasets. Using these inclusive datasets of sensors in deep neural networks, high accuracy velocity predictions can be achieved. This research builds upon previous findings that Long Short-Term Memory (LSTM) deep neural networks provide low error velocity prediction. We developed an LSTM deep neural network that uses different groups of datasets collected in Fort Collins, Colorado. Synchronous data was gathered using a test vehicle equipped with sensors to measure ego vehicle position
Gaikwad, Tushar, Rabinowitz, Aaron, Motallebiaraghi, Farhang, Bradley, Thomas, Asher, Zachary, Fong, Alvis, Meyer, Rick
Evaluation of Laminated Side Window Glazing Coding and Rollover Ejection Mitigation Performance Using NASS-CDS2020-01-121604/14/2020
Occupant ejection has been identified as a safety problem for decades, particularly in rollover crashes. While field accident studies have repeatedly demonstrated the effectiveness of seat belts in mitigating rollover ejection and injuries, the use of laminated glass in side window positions has been suggested as a means to mitigate occupant ejection. Limited data is available on the field performance of laminated glass in preventing ejection. This study utilized 1997-2015 NASS-CDS data to investigate the reliability of the glazing coding variables in the database and determine if any conclusions can be drawn regarding the effect of different side window glazing types on occupant ejection. An initial query was run for 1997-2016 model year vehicles involved in side impacts to evaluate glazing coding within NASS-CDS. Sixteen individual cases were identified where the first-row side window glass was coded as both laminated and as in-place and holed, out-of-place and not holed, out-of
Parenteau, Chantal, Smedley, Janine, Campbell, Ian C., Carhart, Michael
Augmented Reality Projection for Driver Assistance in Autonomous Vehicles2020-01-103504/14/2020
Augmented Reality (AR), which involves the integration of digital information with our physical environment in real-time, has been steadily growing over the past few years, finding its way into multiple areas of our lives. Augmented Reality (AR) in automotive vehicles has contributed to revolutionizing the way passengers and drivers access information, acquire knowledge and integrate into the physical spaces and destinations visited. The studies produced concerning this field are still limited, particularly in the perception of how users adopt technology and what use they make of it. On the other hand, even more limited are the studies that consider the role of stakeholders in the implementation of AR technology. In this paper, we discuss and propose solutions for following ADAS applications using projection unit mounted on board projecting on the windshield. 5G in your route (signal strength - android applications on HU to detect the signal strength and display it on projection unit
Chandupatla, Srinivas, Yerram, Nalinikanth, Achuthan, Balasubramanian
Evaluation of Laminated Side Glazing and Curtain Airbags for Occupant Containment in Rollover2020-01-097604/14/2020
By their nature as chaotic, high-energy events, rollovers pose a high risk of injury to unrestrained occupants, in particular through exposure to projected perimeter contact and ejection. While seat belts have long been accepted as a highly effective means of retaining and restraining occupants in rollover crashes, it has been suggested that technologies such as laminated safety glazing or rollover-activated side curtain airbags (RSCAs) could alternatively provide effective occupant containment. In this study, a full-scale dolly rollover crash test was performed to assess the occupant containment capability of laminated side glazing and RSCAs in a high-severity rollover event. This allowed for the analysis of unrestrained occupant kinematics during interaction with laminated side glazing and RSCAs and evaluation of failure modes and limitations of laminated glazing and RSCAs as they relate to partial and complete ejection of unrestrained occupants. The dolly rollover was performed with
Miller, Bruce, Smedley, Janine, Carhart, Michael, Sharpe, Sarah, Krishnaswami, Ram
In-situ studies on the effect of solar control glazings on in-cabin thermal environment for hot and humid climatic zones2020-01-125704/14/2020
Thermal comfort in a passenger cabin is the basic necessity of an occupant especially in hot and humid climatic conditions. It is known that the reflective glazing solutions provide better thermal comfort inside the cabin due to significant reflection of IR part of solar radiation. However, in hot and humid climatic zones like India, significant reduction in heat load can also be achieved through cost effective solar control absorbing glazings. Thus, the present work aims to study the effect of solar control absorbing glazings on cabin inside temperatures and its impact on thermal comfort of the occupants in tropical climates. A combination of glazing sets with a range of solar energy transmission and absorption values are considered for the study. Indoor soak and cool tests are performed on a sedan model with multiple sets of solar control absorbing glass combinations. A constant ambient temperature of 38˚C and solar radiation of 1000W/m2 are maintained throughout the tests. Wind
Tamalapakula, Jyothi Latha
Atomically Thin Heat Shield Protects Electronic DevicesTBMG-3526610/01/2019
Excess heat given off by smartphones, laptops, and other electronic devices contributes to malfunctions and, in extreme cases, can even cause lithium batteries to explode. To guard against issues, engineers often insert glass, plastic, or layers of air as insulation to prevent heat-generating components like microprocessors from causing damage.
Tuning Material Color and Thermal Properties SeparatelyTBMG-3489808/01/2019
The color of a material can often tell how it handles heat. With clothing, for example, the darker the pigment, the warmer you're likely to feel on a hot day. Likewise, the more transparent a glass window, the more heat it can let through. A material's responses to visible and infrared radiation are often naturally linked.
Simulations of Thin Film Dynamics on a Flat Plate and an Airfoil2019-01-193806/10/2019
The goal of the present study is to investigate the dynamics of a thin water film on a flat plate and an airfoil using direct numerical simulation (DNS). The first case for a wetted flat plate is used to model former experiments and investigate the dynamics of a wind-driven water film. The second case for a thin film on a NACA 0012 airfoil of chord length 0.5 m is used to investigate the dynamics of a wind-driven water film on a curved surface. Particular attention is paid to the interaction between the liquid film and the air shear-layer above the film. As the incoming airflow moves over the thin water film, instability is triggered at the gas-liquid interface. Interfacial waves develop and are advected downstream. The interaction between the air flow and the interfacial waves induces shedding vortices near the interface, which in turn perturb the liquid film farther downstream. Simulations are performed using the open source multiphase flow solvers, Gerris and Basilisk. Both solvers
Sakakeeny, Jordan, McClain, Stephen T., Ling, Yue
Separating-Reattaching Flows Over an Iced Airfoil2019-01-194606/10/2019
Delayed Detached Eddy Simulations (DDES) of separating-reattaching flows on the suction side of an ice-contaminated airfoil were conducted. A single-section straight-wing NACA23012 airfoil with leading-edge ice was studied. The geometry represents a realistic glaze horn-ice contamination obtained during the icing test campaigns described in [1], which has aerodynamic data for comparison. The three-dimensional transient flow behavior was simulated using the open-source flow solver OVERFLOW, version 2.2l [2] developed by NASA Langley Research Center. Configurations at three angles of attack that exhibit unsteady flow behavior starting with the bursting angle were examined at Mach number of 0.18 and Reynolds number of 1.8x106. As the stall angle was approached the aerodynamic performance parameters displayed large-scale unsteadiness where periods of attached and separated flows were observed. The time-averaged results show good agreement with the aerodynamic test data. The calculated
Oztekin, Ezgi, Riley, James
A Penalization Method for 2D Ice Accretion Simulations2019-01-193906/10/2019
Numerical tools for 3D in-flight icing simulations are not straightforward to automate when seeking robustness and quality of the results. Difficulties arise from the geometry and mesh updates which need to be treated with care to avoid folding of the geometry, negative volumes or poor mesh quality. This paper aims at solving the mesh update issue by avoiding the re-meshing of the iced geometry. An immersed boundary method (here, penalization) is applied to a 2D ice accretion suite for multi-step icing simulations. The suggested approach starts from a standard body-fitted mesh, thus keeping the same solution for the first icing layer. Then, instead of updating the mesh, a penalization method is applied including: the detection of the immersed boundary, the penalization of the volume solvers to impose the boundary condition and the extraction of the surface data from the field solution. Although the current work is intended for 3D simulations, the content of this paper is limited to 2D
Lavoie, Pierre, Blanchard, Ghislain, Radenac, Emmanuel, Laurendeau, Eric, Villedieu, Philippe
Numerical Simulation of Aircraft and Variable-Pitch Propeller Icing with Explicit Coupling2019-01-195406/10/2019
A 3D CFD methodology is presented to simulate ice build-up on propeller blades exposed to known icing conditions in flight, with automatic blade pitch variation at constant RPM to maintain the desired thrust. One blade of a six-blade propeller and a 70-passenger twin-engine turboprop are analyzed as stand-alone components in a multi-shot quasi-steady icing simulation. The thrust that must be generated by the propellers is obtained from the drag computed on the aircraft. The flight conditions are typical for a 70-passenger twin-engine turboprop in a holding pattern in Appendix C icing conditions: 190 kts at an altitude of 6,000 ft. The rotation rate remains constant at 850 rpm, a typical operating condition for this flight envelope. Two icing conditions are simulated: air static temperature -23 °C, LWC 0.2 g/m3 and MVD 20 microns resulting in rime ice, and air static temperature -16 °C, LWC 0.3 g/m3 and MVD 20 microns resulting in mixed ice with rime to glaze transition in the radial
Ozcer, Isik, Baruzzi, Guido S., Desai, Miraj, Yassin, Maged
A Three-Layer Thermodynamic Model for Ice Crystal Accretion on Warm Surfaces: EMM-C2019-01-196306/10/2019
Ingestion of high altitude atmospheric ice particles can be hazardous to gas turbine engines in flight. Ice accretion may occur in the core compression system, leading to blockage of the core gas path, blade damage and/or flameout. Numerous engine powerloss events since 1990 have been attributed to this mechanism. An expansion in engine certification requirements to incorporate ice crystal conditions has spurred efforts to develop analytical models for phenomenon, as a method of demonstrating safe operation. A necessary component of a complete analytical icing model is a thermodynamic accretion model. Continuity and energy balances are performed using the local flow conditions and the mass fluxes of ice and water that are incident on a surface to predict the accretion growth rate. In this paper, a new thermodynamic model for ice crystal accretion is developed through adaptation of the Extended Messinger Model (EMM) from supercooled water conditions to mixed phase conditions (ice
Bucknell, Alexander, McGilvray, Matthew, Gillespie, David, Jones, Geoffrey, Collier, Benjamin
Numerical Investigation of Wiper Drawback2019-01-064004/02/2019
Windscreen wipers are an integral component of the windscreen cleaning systems of most vehicles, trains, cars, trucks, boats and some planes. Wipers are used to clear rain, snow, and dirt from the windscreen pushing the water from the wiped surface. Under certain conditions however, water which has been driven to the edge of the windscreen by the wiper can be drawn back into the driver’s field of view by aerodynamic forces introduced by the wiper motion. This is wiper drawback, an undesirable phenomenon as the water which is drawn back on to the windscreen can reduce driver’s vision and makes the wiper less effective. The phenomena of wiper drawback can be tested for in climatic tunnels using sprayer systems to wet the windscreen. However, these tests require a bespoke test property or prototype vehicle, which means that the tests are done fairly late in the development of the vehicle. Furthermore, these results do not provide significant insight into the mechanisms driving the wiper
Jilesen, Jonathan, Gaylard, Adrian, Linden, Tom
SAE Eye on Engineering: Conti's Virtual A-Pillar tech1239911/13/2018
The pillars that frame both sides of your car's windshield are known as the A pillars. In this episode of SAE Eye on Engineering, Editor-in-Chief Lindsay Brooke looks at Continental's new "Virtual" A pillar. SAE Eye on Engineering also airs Monday mornings on WJR 760 AM Detroit's Paul W. Smith Show.
Products of Tomorrow: October 2018TBMG-3309510/01/2018
This column presents technologies that have applications in commercial areas, possibly creating the products of tomorrow. To learn more about each technology, see the contact information provided for that innovation.
2021-12-29.TEST Practical Approaches for Detecting DoS Attacks on CAN Network2018-01-001904/03/2018
Some of the recent studies reveal that it is possible to access the in-vehicle networks and inject malicious messages to alter the behavior of the vehicle. Researchers have shown that, it is possible to hack a car’s communication network and remotely take control of brake, steering, power window systems, etc. Hence, it becomes inevitable to implement schemes that detect anomalies and prevent attacks on Controller Area Network (CAN). Our work explores the complete anomaly detection process for CAN. We cover the techniques followed, available tools and challenges at every stage. Beginning with what makes CAN protocol vulnerable, we discuss case studies about attacks on CAN with major focus on Denial of Service (DoS) attack. We analyze the pattern of normal CAN messages obtained from real vehicle, along with patterns of simulated attack data using different methods/tools. The work in this paper presents a statistical data analysis based machine learning algorithm with two approaches “time
Kalyanasundaram, Pallavi, Kareti, Venkatesh, Sambranikar, Meghana, SS, Narendra Kumar, Ranadive, Priti
Simplifications Applied to Simulation of Turbulence Induced by a Side View Mirror of a Full-Scale Truck Using DES2018-01-070804/03/2018
In this paper, the turbulent flow induced by a production side-view mirror assembled on a full-scale production truck is simulated using a compressible k-ω SST detached eddy simulation (DES) approach -- the improved delayed DES (IDDES). The truck configuration consists of a compartment and a trailer. Due to the large size and geometric complexity of the configuration, some simplifications are applied to the simulation. A purpose of this work is to investigate whether the simplifications are suitable to obtain the reasonable properties of the flow near the side-view mirror. Another objective is to study the aerodynamic performances of the mirror. The configuration is simplified regarding two treatments. The first treatment is to retain the key exterior components of the truck body while removing the small gaps and structures. Furthermore, the trailer is shaped in an apex-truncated square pyramid. This simplification is proposed based on the assumption that the downstream flow near the
Yao, Huadong, Chroneer, Zenitha, Davidson, Lars
Utilizing spectral analysis to quantify resolution of low frequency behavior in testing commercial vehicles2018-01-074704/03/2018
Despite the recent broadening of acceptable test methods for certifying aerodynamic performance, there has been little attention on how to determine the time averaging window used for providing mean forces. This is of particular relevance to the assessment of commercial vehicles as they are significantly affected by low-frequency patterns that are hard to predict and vary with different geometry configurations. Published guidelines in the industry suggest that good engineering judgement be used and a qualitative assessment of force histories is adequate. These suggested methods leave the accuracy of the time averaging to the experience and judgement of the user and is highly dependent on the specific characteristics of the benchmark case. Furthermore these methods are not able to quantify the error present due to motions slower than length of the sampled data. In order to robustly determine appropriate averaging window a new method is proposed which utilizes spectral analysis of the
Landfried, Douglas Tyler, Alex, David, Mosedale, Andrew
Enhancing Driver Awareness Using See-Through Technology2018-01-061104/03/2018
This paper presents a real-time application of see-through technology using computer vision (e.g., object detection) and Vehicle-to-X (V2X) communication (e.g., Vehicle-to-Vehicle (V2V) and Vehicle-to-Infrastructure (V2I)). Each access point (AP) was connected to Chattanooga’s fiber optics internet, supporting a data transfer rate up to 10-Gbps. Using a 5Ghz frequency, vehicular communications were set up with a seamless handover for transferring real-time data. Two web cameras acting as clients were mounted on the windshield of two of three vehicles to send image data to the offsite server. Using multi-threaded programming, both image feeds were processed simultaneously. Once the server received the images, it performed an object recognition algorithm on each image using a convolutional neural network (CNN). Post- identification, the images from the second vehicle were sent and overlaid dynamically to the third vehicle’s image. This repetitive overlapping of images allowed the third
Thompson, Rebekah L., HU, Zhen, Cho, Jin, Stovall, Jose, Sartipi, Mina
Effects of Rear Slant Angles on the Flow Characteristics of the Ahmed Body by IDDES Simulations2018-01-072004/03/2018
The present study aims to investigate the effects of the several rear slant angles, φ = 25°, 30°, 32°, 33° and 35°, on the wake characteristics downstream of the Ahmed body because the angle of the rear window plays an important role in the flow characteristics. This work presents numerical simulations using ISIS-CFD flow solver which is developed by Centrale Nantes and CNRS. The turbulence model used is an hybrid RANS-LES model: the Improved Delayed Detached Eddy Simulation (IDDES). Detailed discussions of the flow features are provided using time-averaged streamlines, vorticity contours, turbulent kinetic energy contours and an iso-surface of l2. Drag and lift coefficients are also presented. In the symmetry plane, three critical flow points, which correspond to foci of separation and saddle point in the wake of the Ahmed body, and the focus of separation over the slanted surface are presented. When the slant angle increases, these critical points move near the Ahmed body before
Guilmineau, Emmanuel
Investigation of Interior Noise from Generic Side- View Mirror Using Incompressible and Compressible Solvers of DES and LES2018-01-073504/03/2018
Exterior turbulent flow is an important source of automobile cabin interior noise. The turbulent flow impacts the windows of the cabins to excite the structural vibration that emits the interior noise. Meanwhile, the exterior noise generated from the turbulent flow can also cause the window vibration and generate the interior noise. Side-view mirrors mounted upstream of the windows are one of the predominant body parts inducing the turbulent flow. In this paper, we investigate the interior noise caused by a generic side-view mirror. The interior noise propagates in a cuboid cavity with a rectangular glass window. The exterior flow and the exterior noise are computed using advanced CFD methods: compressible large eddy simulation, compressible detached eddy simulation (DES), incompressible DES, and incompressible DES coupled with an acoustic wave model. The last method is used to simulate the hydrodynamic and acoustic pressure separately. The pressure fluctuations of the flow and noise
Yao, Huadong, Davidson, Lars, Chroneer, Zenitha
Ultra-Light Weight Automotive Door: Design and Validation2018-01-011104/03/2018
An Ultra-Light Door (ULD) has been developed that is 40% lighter than a baseline 2016 mid-size vehicle’s driver side door. The ULD scope encompasses the entire door, including the door-in-white (DIW), interior trim, glazing, hardware, wiring, etc. To achieve such a substantial mass reduction while still meeting the baseline vehicle’s performance metrics (including safety, durability, NVH, appearance, etc.) at a minimal cost increase, the door design relies on a comprehensive full system approach that includes a unique architecture in addition to lightweight materials and components. This paper details the ULD design concept, simulated performance results, the current status of vehicle level validation, and comparisons between component level CAE predicted performance and physical test results.
Reaburn, Timothy, Skszek, Timothy W.
Measurements of the Evaporation Behavior of the Film of Fuel Blends2018-01-029004/03/2018
The formation of fuel film in the combustion cylinder affects the mixing process of the air and the fuel, and the process of the combustion propagation in engines. Some models of film evaporation have been developed to predict the evaporation behavior of the film, but rarely experimental results have been produced, especially when the temperature is high. In this study, the evaporation behavior of the film of different species of oil and their blends at different temperature are observed. The 45 μL films of isooctane, 1-propanol, 1-butanol, 1-pentanol, and their blends were placed on a quartz glass substrate in the closed temperature-controlled chamber. The shape change of the film during evaporation was monitored by a high-speed camera through the window of the chamber. First, the binary blends film of isooctane and one of the other three oils were evaporated at 30 °C, 50 °C, 70 °C and 90 °C. Secondly, the pure films of isooctane, 1-propyl alcohol, 1-butanol and 1-pentanol were
Liang, Zhengxing, Yan, Junhao, Li, Gang, Lee, Timothy, Zhang, Li, Lee, Chia-Fon
Measurement of Soot Concentration in a Prototype Multi-Hole Diesel Injector by High-Speed Color Diffused Back Illumination Technique2017-01-225510/08/2017
A prototype multi-hole diesel injector operating with n-heptane fuel from a high-pressure common rail system is used in a high-pressure and high-temperature test rig capable of reaching 1100 Kelvin and 150 bar under different oxygen concentrations. A novel optical set-up capable of visualizing the soot cloud evolution in the fuel jet from 30 to 85 millimeters from the nozzle exit with the high-speed color diffused back illumination technique is used as a result of the insertion of a high-pressure window in the injector holder opposite to the frontal window of the vessel. The experiments performed in this work used one wavelength provide information about physical of the soot properties, experimental results variating the operational conditions show the reduction of soot formation with an increase in injection pressure, a reduction in ambient temperature, a reduction in oxygen concentration or a reduction in ambient density.
Payri, Raul, Gimeno, Jaime, Cardona, Santiago, Ayyapureddi, Sridhar
Products of Tomorrow: October 2017TBMG-2769210/01/2017
This column presents technologies that have applications in commercial areas, possibly creating the products of tomorrow. To learn more about each technology, see the contact information provided for that innovation.
Plasma-Assisted Catalytic Reverse Water Gas Shift ReactorTBMG-2767810/01/2017
For improving CO2 conversions for a low-temperature CO2 methanation process, a mechanism of using reverse water gas shift (RWGS) reaction as an intermediate step to generate the more reactive CO species for the methanation process was developed. The challenge was to achieve useful conversions of RWGS reaction (CO2 to CO by hydrogenation) at low temperatures (200-300 °C), which is not possible with conventional catalytic reactors. Achieving useful conversions (up to ~50%) is not possible at the desired temperature window of 200-300 °C with a conventional catalytic reactor due to equilibrium limitations of the endothermic RWGS reactor.
Combined Discrete-Continuous Simulation for Maintenance Training and Execution2017-01-202509/19/2017
One of the most important activities associated with the Aerospace or Defense industry is maintenance. Maintainability procedures have a direct impact on safety and operational availability of systems. The processes and procedures that are used during maintenance activities, whether removing and replacing a component of a system, or conducting troubleshooting, are generally discrete by design, and in most cases, a maintainer, or a field service representative (FSR), will follow a sequence of steps as part of a maintenance work package or work instruction to complete the necessary tasks. Depending on the system, those maintenance activities could be complex, requiring a large maintenance window and the availability of resources to ensure completion. In order to successfully accomplish those complex tasks, besides having access to the required hardware/software and tools, one of two alternatives need to exist: either the maintainer is well trained and experienced, or the maintenance work
Rodriguez, Eugenio
Products of Tomorrow: September 2017TBMG-2752709/01/2017
This column presents technologies that have applications in commercial areas, possibly creating the products of tomorrow. To learn more about each technology, see the contact information provided for that innovation.
An Analysis on Automotive Side Window Buffeting Using Scale Adaptive Simulation2017-01-178806/05/2017
Automotive window buffeting is a source of vehicle occupant’s discomfort and annoyance. Original equipment manufacturers (OEM) are using both experimental and numerical methods to address this issue. With major advances in computational power and numerical modelling, it is now possible to model complex aero acoustic problems using numerical tools like CFD. Although the direct turbulence model LES is preferred to simulate aero-acoustic problems, it is computationally expensive for many industrial applications. Hybrid turbulence models can be used to model aero acoustic problems for industrial applications. In this paper, the numerical modelling of side window buffeting in a generic passenger car is presented. The numerical modelling is performed with the hybrid turbulence model Scale Adaptive Simulation (SAS) using a commercial CFD code. While the acoustic generation is modelled by solving compressible Navier-Stokes equation, integral method Ffowcs-Williams & Hawkings (FWH) is used to
Ulli, Kishore Chand, Gade, Upender Rao
A Modal Study of Damping Treatments to Improve Low Frequency Sound Transmission Loss of a Structure2017-01-185206/05/2017
Most of NVH related issues start from the vibration of structures where often the vibration near resonance frequencies radiates the energy in terms of sound. This phenomenon is more problematic at lower frequencies by structureborne excitation from powertrain or related components. This paper discusses a laboratory based case study where different visco-elastic materials were evaluated on a bench study and then carried on to a system level evaluation. A body panel with a glazing system was used to study both airborne and structureborne noise radiation. System level studies were carried out using experimental modal analysis to shift and tune the mode shapes of the structure using visco-elastic materials with appropriate damping properties to increase the sound transmission loss. This paper discusses the findings of the study where the mode shapes of the panel were shifted and resulted in an increase in sound transmission loss. This eventually resulted in reduced sound level inside the
Deshpande, Satyajeet P., Saha, Pranab, Cone, Kerry
Two-Component Injection Molding as a Noise Countermeasure for Polycarbonate Glazing2017-01-181706/05/2017
Polycarbonate (PC) glazing as a one-for-one glass replacement offers a 50% weight reduction, but exhibits several dB lower sound transmission loss (STL) in the low frequency range where tire and engine noise are dominant. In the high frequency range where wind noise is dominant, PC glazing offers an STL at least comparable to its glass counterpart, and an STL exceeding glass when this frequency range encompasses the glass coincidence frequency. However, a key value proposition of PC glazing is the opportunity for feature integration afforded by the injection molding process generally used for forming such glazing. Two-component (2K) molding fuses a second shot of plastic material behind, and along the perimeter of, the transparent PC first shot. This second shot can incorporate features and implement functions that require additional components attached or peripheral to a glass version. In effect, a portion of the weight reduction entitlement for PC glazing is transferred to the host
Gasworth, Steven M., Nilajkar, Vasudev, Terragni, Matteo
Using the Modal Response of Window Vibrations to Validate SEA Wind Noise Models2017-01-180706/05/2017
The SEA model of wind noise requires the quantification of both the acoustic as well as the turbulent flow contributions to the exterior pressure. The acoustic pressure is difficult to measure because it is usually much lower in amplitude than the turbulent pressure. However, the coupling of the acoustic pressure to the surface vibration is usually much stronger than the turbulent pressure, especially in the acoustic coincidence frequency range. The coupling is determined by the spatial matching between the pressure and the vibration which can be described by the wavenumber spectra. This paper uses measured vibration modes of a vehicle window to determine the coupling to both acoustic and turbulent pressure fields and compares these to the results from an SEA model. The interior acoustic intensity radiating from the window during road tests is also used to validate the results.
DeJong, Richard, Ebbitt, Gordon
Practical Design Considerations for Lightweight Windshield Applications2017-01-130603/28/2017
Automotive manufacturers are requiring lightweight materials, including glazing materials to improve vehicle fuel economy mandates. Since windshields are one of the largest glazing surface areas, reducing the thickness of the glass in its construction can significantly provide weight savings opportunities. Automotive glazing design considerations must include overall glass strength, rigidity, acoustical, and solar performance, which are affected by changes of glass thicknesses. This paper will evaluate those design considerations in the lightweighting of windshield glazings. One important design consideration for the windshield position is the impact of debris from the environment. Lightweighting of glazings in this body position affects the way the construction reacts to an impact. Use of asymmetry in glass plies in a laminated construction can have a marked effect on the part’s impact performance and surface damage creation. Various lightweight glazing constructions will be analyzed
Walawender, Chester, Ulizio, Michael, Lampman, DeWitt, Rustagi, Mukesh, Skeen, Jason
Simplified Approach for Optimizing Lightening Holes in Truck Frames for Durability Performance2017-01-134503/28/2017
During development of new vehicles, CAE driven optimizations are helpful in achieving the optimal designs. In the early phase of vehicle development there is an opportunity to explore shape changes, gage reduction or alternative materials as enablers to reduce weight. However, in later phases of vehicle development the window of opportunity closes on most of the enablers discussed above. The paper discusses a simplified methodology for reducing the weight in design cycle for truck frames using parametric Design of Experiments (DOE). In body-on-frame vehicles, reducing the weight of the frame in the design cycle without down gaging involves introducing lightening holes or cutouts while still maintaining the fatigue life. It is also known that the lightening holes might cause stress risers and be detrimental to the fatigue life of the component. Thus the ability to identify cutout locations while maintaining the durability performance becomes very critical. This paper describes a method
bhat, Ramachandra, Sharma, Nitin, Rivard, Clifford, Thomson, Kevin
A Statistical Description of Knock Intensity and Its Prediction2017-01-065903/28/2017
Cycle-to-cycle variation in combustion phasing and combustion rate cause knock to occur differently in every cycle. This is found to be true even if the end gas thermo-chemical time history is the same. Three cycles are shown that have matched combustion phasing, combustion rate, and time of knock onset, but have knock intensity that differs by a factor of six. Thus, the prediction of knock intensity must include a stochastic component. It is shown that there is a relationship between the maximum possible knock intensity and the unburned fuel energy at the time of knock onset. Further, for a small window of unburned energy at knock onset, the probability density function of knock intensity is self similar when scaled by the 95th percentile of the cumulative distribution, and log-normal in shape. A methodology to predict the maximum possible knock intensity based on the volumetric expansion rate of the end gas was developed, and the expansion rate was modeled based on blast wave theory
Ghandhi, Jaal, Kim, Kenneth Seonguk
Investigation of a Dual HVAC MAC System with Three Row Ducts Using 1D Modeling2017-01-016403/28/2017
In an automotive air-conditioning (AC) system, upfront prediction of the cabin cool down rate in the initial design stage will help in reducing the overall product development (PD) time. Vehicle having higher seating capacity will have higher thermal load and providing thermal comfort to all passengers uniformly is a challenging task for the automotive HVAC (Heating Ventilation and Air conditioning) industry. Dual HVAC unit is generally used to provide uniform cooling to a large cabin volume. One dimensional (1D) simulation is being extensively used to predict the HVAC performance during the initial stage of PD. The refrigerant loop with components such as compressor, condenser, TXV and evaporator was modeled. The complicated vehicle cabin including the glazing surfaces and enclosures were modeled as a three row duct system using 1D tool AMESim®. The material type, density, specific heat capacity and thermal conductivity of the material were specified. The actual vehicle driving
Muthusamy, Venkatesan, Sathish Kumar, S., Sambandan, Saravanan
Sensitivity Analysis of Windshield Defrost Characteristics Impact on Occupant Thermal Comfort2017-01-014303/28/2017
During cabin warm-up, effective air distribution by vehicle climate control systems plays a vital role. For adequate visibility to the driver, major portion of the air is required to be delivered through the defrost center ducts to clear the windshield. HVAC unit deliver hot air with help of cabin heater and PTC heater. When hot air interacts with cold windshield it causes thermal losses, and windshield act as sink. This process may causes in delay of cabin warming during consecutive cabin warming process. Thus it becomes essential to predict the effect of different windscreen defrost characteristics. In this paper, sensitivity analysis is carried for different windscreen defrosts characteristics like ambient conditions, modes of operation; change in material properties along with occupant thermal comfort is predicted. An integrated 1D/3D CFD approach is proposed to evaluate these conditions. Detailed thermal boundary conditions are considered in 1D heat transfer method and coupled
Kandasamy, Neelakandan, Whelan, Steve
Safety Release Fasteners Enable New Cabin/Cargo Decompression Concept2016-01-208209/27/2016
In the frame of incremental product improvement, AIRBUS has developed and implemented a new innovative rapid decompression / pressure relieve concept for the cargo compartment area. The core change lays with detaching the complete cargo lining panels from the substructure in case of a rapid decompression in the cargo area instead of using dedicated blow in panels. In that way, pressure equilibrium can be achieved by air flow through the opened areas around the cargo lining panels rather than through specific blow out / blow in venting areas. The key for this is a self-detaching fastener AIRBUS has developed in an outstanding cooperation with ARCONIC Fastening Systems & Rings (former Alcoa Fastening Systems & Rings) in Kelkheim, Germany. These fasteners are installed to keep the cargo lining panels in place and tight against smoke in case of fire which is one of the main purposes for their use. In case of a rapid decompression event in the cargo area, the multi-piece self-detaching
Schomaker, Ralf, Knickrehm, Björn, Langediers, Jürgen
Automatic Drilling, Countersink and Riveting Experience. Aernnova Highlights Based on More Than 20 Million of Fasteners Installed2016-01-208909/27/2016
Aernnova experience on automatic drilling operations started in 1,999. The company signed a new contract with Embraer, to design, manufacture and assembly several structures of the model 170. It was big news for the company. But after that minute of pride, manufacturing engineering people of the company started to think about the process to assemble those big panels of the Horizontal Stabilizer, Vertical Stabilizer and Rear Fuselages in the best Quality and Cost. There were a lot of rows of rivets to install. Some ideas arisen, but the final decision was to forget the available processes at that time and think about to automate the drilling, countersink and riveting of the stringers, doublers and window frames to the panels. There were a lot of doubts, figures to do and obstacles, but the company took the decision of going ahead with that process. That step changed the state of the art at that time in the company. The investment was important, the risks were high, and the beginnings
Guerra cEng, Jose, Castillo, Miguel Angel
Research on Temperature and Strain Rate Dependent Viscoelastic Response of Polyvinyl Butaral Film2016-01-051904/05/2016
The mechanical behavior of polyvinyl butyral (PVB) film plays an important role in windshield crashworthiness and pedestrian protection and should be depth study. In this article, the uniaxial tension tests of PVB film at various strain rates (0.001 s-1, 0.01 s-1, 0.1 s-1, 1 s-1) and temperatures (-10°C, 0°C, 10°C, 23°C, 40°C, 55°C, 70°C) are conducted to investigate its mechanical behavior. Then, temperature and strain rate dependent viscoelastic characteristics of PVB are systematically studied. The results show that PVB is a kind of temperature and strain rate sensitive thermal viscoelastic material. Temperature increase and strain rate decrease have the same influence on mechanical properties of PVB. Besides, the mechanical characteristics of PVB change non-linearly with temperature and strain rate. Finally, two thermal viscoelastic constitutive model (ZWT model and DSGZ model) are suggested to describe the tension behavior of PVB film at various strain rates and temperatures
Xu, Xiaoqing, Liu, Bohan, Wang, Yan, Li, Yibing
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