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As an annual subscription, the Wiley Cyber Security Collection Add-On is available for purchase along with one or both of the following: Wiley Aerospace Collection Wiley Automotive Collection The titles from the Wiley Cyber Security Collection are included in the SAE MOBILUS® eBook Package. Titles: Network Forensics Penetration Testing Essentials Security in Fixed and Wireless Networks, 2nd Edition The Network Security Test Lab: A Step-by-Step Guide Risk Centric Threat Modeling: Process for Attack Simulation and Threat Analysis Applied Cryptography: Protocols, Algorithms and Source Code in C, 20th Anniversary Edition Computer Security Handbook, Set, 6th Edition Threat Modeling: Designing for Security Other available Wiley collections: Wiley SAE MOBILUS eBook Package Wiley Aerospace Collection Wiley Automotive Collection Wiley Computer Systems Collection Add-On (purchasable with the Wiley Aerospace Collection and/or the Wiley Automotive Collection)

A new and unique electric vehicle powertrain model based on bidirectional power flow for propel and regenerative brake power capture is developed and applied to production battery electric vehicles. The model is based on a Willans line model to relate power input from the battery and power output to tractive effort, with one set of parameters (marginal efficiency and an offset loss) for the bidirectional power flow through the powertrain. An electric accessory load is included for the propel, brake and idle phases of vehicle operation. In addition, regenerative brake energy capture is limited with a regen fraction (where the balance goes to friction braking), a power limit, and a low-speed cutoff limit. The purpose of the model is to predict energy consumption and range using only tractive effort based on EPA published road load and test mass (test car list data) and vehicle powertrain parameters derived from EPA reported unadjusted UDDS and HWFET energy consumption.

In order to understand the flow and wind noise characteristics generated by the outside rearview (OSRV) mirror, a series of wind noise measurements for two production mirrors was conducted at the GM Aerodynamics Lab (GMAL) wind tunnel. These measurements included the time-averaged static pressures, surface noise sources, and far field propagation noise. The data obtained in this investigation will be used for future CFD numerical validations. The two mirrors chosen for the test are the GMT360 (a truck mirror) and the GMX320 (a sedan mirror). The test mirror was mounted on an elevated table which was specially designed for the current project to avoid any significant flow boundary layer buildup on the wind tunnel floor. The test conditions reported in this paper include four inlet speeds of 30, 50, 70 and 90 mph at 0 yaw angle. To record the wind noise sources, nine surface flush-mount microphones were used.

Recent developments in the prediction of the contribution of wind noise to the interior SPL have opened a realm of new possibilities in terms of i) how the convective and acoustic sources terms can be identified, ii) how the interaction between the source terms and the side glass can be described and finally iii) how the transfer path from the sources to the interior of the vehicle can be modelled. This paper discusses in detail these three aspects of wind noise simulation and recommends appropriate methods to deliver required results at the right time based on i) simulation and experimental data availability, ii) design stage and iii) time available to deliver these results. Several simulation methods are used to represent the physical phenomena involved such as CFD, FEM, BEM, FE/SEA Coupled and SEA.

The current ability of the Virtual Aerodynamic/ Aeroacoustic Wind Tunnel to predict interior vehicle sound pressure levels is demonstrated using an automobile model which has variable windshield angles. This prediction method uses time-averaged flow solutions from a lattice gas CFD code coupled with wave number-frequency spectra for the various flow regimes to calculate the side window vibration from which the sound pressure level spectrum at the driver's ear is determined. These predictions are compared to experimental wind tunnel data. The results demonstrate the ability of this methodology to correctly predict wind noise spectral trends as well as the overall loudness at the driver's ear. A more sophisticated simulation method employing the same lattice gas code is investigated for prediction of the time-accurate flow field necessary to compute the actual side glass pressure spectra.

The use of devices to reduce aerodynamic drag on large trailers and save fuel in long-haul, over-the-road freight operations has spurred innovation and prompted some trucking fleets to use them in combinations to achieve even greater gains in fuel-efficiency. This paper examines aerodynamic performance and potential drag reduction benefits of using trailer aerodynamic components in combinations based upon wind tunnel test data. Representations of SmartWay-verified trailer aerodynamic components were tested on a one-eighth scale model of a class 8 sleeper tractor and a fifty three foot, van trailer model. The open-jet wind tunnel employed a rolling floor to reduce floor boundary layer interference. The drag impacts of aerodynamic packages are evaluated for both van and refrigerated trailers. Additionally, the interactions between individual aerodynamic devices is investigated.

The Swift Aero wind tunnel is designed to test as large as 50% scale model race cars on a moving ground belt at speeds up to 140 mph. The facility is described and results of the calibration depicting flow quality in the test section are given. A demonstration model of an Indy car is also maintained for calibration purposes and measured results are presented. The data clearly show the importance of simulating the wheel and road boundary condition on the measured vehicle forces and pressures.

This paper documents the development of the capability to test MAVs (Micro Air Vehicles) in the University of Florida’s wind tunnel facility. The main goal of this work was to obtain, with a reliable procedure, good quality experimental data from wind tunnel tests of air vehicles at low Reynolds numbers, in the order of 100,000. An overview of the instrumentation and data analysis techniques will be presented, followed by some samples of results from tests on specific aircraft. A standard aerodynamic characterization test was developed to perform a “quick” System Identification (SID) characterization of an air vehicle. The requirements for those tests were established by the modeling and control portion of the project. The test procedure was aimed to find the main aerodynamic derivatives that will be used to model the aircraft and design the flight control system. Three distinctly different vehicles ranging in size from 60 cm to 15 cm wingspan are discussed.

A 1:12 scale model based on the Sokol A350 Advanced Flying Automobile Concept was examined in the San Diego State University Low Speed Wind Tunnel for performance and stability characteristics. Observation showed that the model stalled at angles of attack above 12 degrees, corresponding to a maximum coefficient of lift of 1.54 and a drag coefficient of .284 for the wing center position. Analysis of the moments revealed that the test model was unstable with the current design specifications, however varying the wing location provided additional insight on the stability of the model. With design changes based on moving the center of gravity forward, the prototype vehicle is capable of creating enough lift to fly safely.

Results of a recent low-speed wind-tunnel investigation conducted to define the forebody flow on a 16% scale model of the NASA High Angle-of-Attack Research Vehicle (HARV), an F-18 configuration, are presented with analysis. Measurements include force and moment data, oil-flow visualizations, and surface pressure data taken at angles of attack near and above maximum lift (36° to 52°) at a Reynolds number of one million based on mean aerodynamic chord. The results presented identify the key flow-field features on the forebody including the wing-body strake.

Wind tunnels provide a convenient, repeatable method of assessing vehicle engine cooling, yet important draw-backs are the lack of a moving ground and rotating wheels, blockage constraints and, in some tunnels, the inability to simulate ambient temperatures. A series of on-road and wind-tunnel experiments has been conducted to validate a process for evaluating vehicle cooling system performance in a high blockage aerodynamic wind tunnel with a fixed ground simulation. Airflow through the vehicle front air intake was measured via a series of pressure taps and the wind-tunnel velocity was adjusted to match the corresponding pressures found during the road tests. In order to cope with the inability to simulate ambient temperatures, the technique of Specific Dissipation (SD) was used (which has previously been shown to overcome this problem).

Window buffeting is a major source of flow induced sound and vibration. This paper will describe window buffeting measurements acquired on a full scale vehicle as well as two different simplified small scale models. The experimental data sets included microphone and phase averaged Particle Image Velocimetry (PIV) measurements both of which show that the flow physics are qualitatively and quantitatively similar in all cases. The implication of this result is that simplified laboratory models of a vehicle are sufficient to study the various aspects of window buffeting in full scale vehicles.

Aerodynamics plays a key role in nowadays vehicle development, aiming efficiency on fuel consumption, which leads to a green technology. Several initiatives around the world are regulating emissions and efficiency of vehicles such as EURO for European Marketing and the INOVAR Auto Project to be implemented in Brazil on 2017. In order to meet requirements in terms of performance, especially on aerodynamics, automakers are focusing on aero-efficient exterior designs and also adding deflectors, covers, active spoilers and several other features to meet the drag coefficient. Usually, the aerodynamics properties of a vehicle are measured in both CFD simulations and wind tunnels, which provide controlled conditions for the test that could be easily reproduced. During the real operations conditions, external factors can affect the flow over the vehicle such as cross wind in open highways.

The purpose of this study is to develop and to validate the techniques required to perform computational analysis of windshield defogging problem. A numerical model of a simplified test vehicle configuration has been built, which includes the passenger compartment, the windshield and the film of the condensed vapor layer. A transient analysis is performed for the conditions in which cold room test data is available. The results of numerical simulation show very reasonable agreement with the test data.

The outside visibility through the windshield and ORVM visibility through the side glasses are critical for safe driving. The frost deposition on the Windshield and side glasses in the cold climatic condition impairs the outside and ORVM visibility during driving and hence leads to an unsafe driving condition. In India, the regulation AIS-084 governs the defrosting standard. The defrosting performance evaluation by testing cannot be performed at concept stage when the vehicle prototype is not available. It also increases the cost of vehicle development due to increase in the number of prototype used for testing. This paper explains about the in-house developed CFD methodology to evaluate the windshield defrosting performance of the vehicle in the concept stage when no vehicle proto is available and cost of countermeasure for defrosting performance improvent is very less. This methodology is implemented for some of the existing models.

Frosted windshields are common appearances during the cold season. The defrosting of the car's windshield is carried out by just blowing hot air against the inside of the pane. This yields growing temperatures also on the outside and finally makes the ice melt. What may sound quite trivial from the user's point of view is rather more complex in terms of analysis and design. The physical phenomena involved are fluid flow and heat transfer in the air on both sides of the glass as well as inside (conjugated heat transfer) and the phase change in the solidified water. For designing purposes of course complete CFD simulations and investigations in test rigs will be performed. But these are very time consuming and expensive, especially if parameter variations and optimizations tasks have to be accomplished. In this paper a modeling and simulation approach is presented, which allows a quasi 3D modeling of the defrosting of windshields based on 1D simulation techniques.

Wipe quality of wiper systems is influenced not only by the definition of the wiper system, but also by the shape of the glass. In order to optimize the overall performance of the system, Valeo Wiper Systems has developed an optimization algorithm, which is based on geometrical criteria. The multi-criteria objective not only considers wipe quality but also constraints by glass feasibility and respect of optical standards. As the direct derivation of the objective functions is not available, a neural network approximation is used at the place of the real function. A neural network with several outputs enables the engineer to include his knowledge in the optimization loop by changing disciplinary weights.

In this paper we investigate the influence of the aerodynamics of the vehicle on the performance of the washer fluid spray. A planar windshield block model with various windshield angles, as well as a “generic” passenger car shape with a fixed windshield angle, is used for the present studies. CFD simulations of the flow field and the spray trajectories are undertaken in this study. The effect of windshield angles, nozzle location and crosswind on the spray performance is presented in this paper. For very large windshield angles of around 60° (measured from the vertical plane), there is no flow separation in the hood-windshield intersection region and the spray trajectory is significantly affected by the airstream for all nozzle locations.

A resonance measurement methodology has been developed by Valeo Wiper Systems in order to determine the best frame tube configuration of a new project. The wiper system mechanism is operated by a motor that propagate noise and vibration to the system. It is known that the frequencies that causes bad sensation to the human hearing are the low frequencies, and it is necessary to determine a frame tube that decreases the vibration and do not pass these vibrations to the vehicle body. There are two ways to reduce the vibration propagated by the motor to the vehicle: broke the resonance in the frame tube with different designs or use grommets in the contact surface between the vehicle body and the wiper mechanism. The resonance analysis has been performed by using an impact hammer and accelerometers that measure the vibration propagated.

This SAE Recommended Practice establishes testing methods and performance requirements for windshield wiping systems on trucks, buses, and multipurpose passenger vehicles with a GVWR of 4500 kg (10000 pounds) or greater and light duty utility vehicles with a GVWR of less than 4500 kg (10000 pounds). The test procedures and minimum performance requirements, outlined in this document, are based on currently available engineering data. It is the intent that all portions of the document will be periodically reviewed and revised as additional data regarding windshield wiping system performance are developed.