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In-vehicle infotainment (IVI) platforms are getting increasingly connected. Besides OEM apps and services, the next generation of IVI platforms are expected to offer integration of third-party apps. Under this anticipated business model, vehicular sensor and event data can be collected and shared with selected third-party apps. To accommodate this trend, Google has been pushing towards standardization among proprietary IVI operating systems with their Android Automotive platform which runs natively on the vehicle’s IVI platform. Unlike Android Auto’s limited functionality of display-projecting certain smartphone apps to the IVI screen, Android Automotive will have access to the in-vehicle network (IVN), and will be able to read and share various vehicular sensor data with third-party apps. This increased connectivity opens new business opportunities for both the car manufacturer as well as third-party businesses, but also introduces a new attack surface on the vehicle.

This presentation is an assessment of the turbulence-stress scale-similarity in an IC engine, which is used for modeling subgrid dissipation in LES. Residual stresses and Leonard stresses were computed after applying progressively smaller spatial filters to measured and simulated velocity distributions. The velocity was measured in the TCC-II engine using planar and stereo PIV taken in three different planes and with three different spatial resolutions, thus yielding two and three velocity components, respectively. Comparisons are made between the stresses computed from the measured velocity and stress computed from the LES resolved-scale velocity from an LES simulation. The results present the degree of similarity between the residual stresses and the Leonard stresses at adjacent scales. The specified filters are systematically reduced in size to the resolution limits of the measurements and simulation.

The blade crossing event of a coaxial counter-rotating rotor is a potential source of noise and impulsive blade loads. Blade crossings occur many times during each rotor revolution. In previous research by the authors, this phenomenon was analyzed by simulating two airfoils passing each other at specified speeds and vertical separation distances, using the compressible Navier-Stokes solver OVERFLOW. The simulations explored mutual aerodynamic interactions associated with thickness, circulation, and compressibility effects. Results revealed the complex nature of the aerodynamic impulses generated by upper/lower airfoil interactions. In this paper, the coaxial rotor system is simulated using two trains of airfoils, vertically offset, and traveling in opposite directions. The simulation represents multiple blade crossings in a rotor revolution by specifying horizontal distances between each airfoil in the train based on the circumferential distance between blade tips.

Our concept studies indicate that a set of reflectors floated in the upper atmosphere can efficiently reduce radiant forcing into the atmosphere. The cost of reducing the radiant forcing sufficiently to reverse the current rate of Global Warming, is well within reach of global financial resources. This paper summarizes the overall concept and focuses on one of the reflector concepts, the Flying Carpet. The basic element of this reflector array is a rigidized reflector sheet towed behind and above a solar-powered, distributed electric-propelled flying wing. The vehicle rises above 30,480 m (100,000 ft) in the daytime by solar power. At night, the very low wing loading of the sheets enables the system to stay well above the controlled airspace ceiling of 18,288 m (60,000 ft). The concept study results are summarized before going into technical issues in implementation. Flag instability is studied in initial wind tunnel experiments.

This paper brings together three special aspects of bluff-body aeromechanics. Experiments using our Continuous Rotation method have developed a knowledge base on the 6-degree-of-freedom aerodynamic loads on over 50 different configurations including parametric variations of canonical shapes, and several practical shapes of interest. Models are mounted on a rod attached to a stepper motor placed on a 6-DOF load cell in a low speed wind tunnel. The aerodynamic loads are ensemble-averaged as phase-resolved azimuthal variations. The load component variations are obtained as discrete Fourier series for each load component versus azimuth about each of 3 primary axes. This capability has enabled aeromechanical simulation of the dynamics of roadable vehicles slung below rotorcraft. In this paper, we explore the genesis of the loads on a CONEX model, as well as models of a short and long container, using the “ROTCFD” family of unstructured Navier-Stokes solvers.

In early phases of conceptual design stages for developing a new car in the modern automobile industry, the lack of systematic methodology to efficiently converge to an agreement between the aesthetics and aerodynamic performance tremendously increases budget and time. During these procedures, one of the most important tasks is to create geometric information which is versatilely morphable upon the demands of both of stylists and engineers. In this perspective, this paper proposes a Spline-based Modeling Algorithm (SMA) to implement into performing aerodynamic design optimization research based on CFD analysis. Once a 3-perspective schematic of a car is given, SMA regresses the backbone boundary lines by using optimum polynomial interpolation methods with the best goodness of fit, eventually reconstructing the 3D shape by linearly interpolating from the extracted boundaries minimizing loss of important geometric features.

The atomization and initial spray formation processes in direct injection engines are not well understood due to the experimental and computational challenges associated with resolving these processes. Although different physical mechanisms, such as aerodynamic-induced instabilities and nozzle-generated turbulence and cavitation, have been proposed in the literature to describe these processes, direct validation of the theoretical basis of these models under engine-relevant conditions has not been possible to date. Recent developments in droplet sizing measurement techniques offer a new opportunity to evaluate droplet size distributions formed in the central and peripheral regions of the spray. There is therefore a need to understand how these measurements might be utilized to validate unobservable physics in the near nozzle-region.

Combat aircraft maneuvering at high angles of attack or in landing approach are likely to encounter conditions where the flow over the swept wings is yawed. This paper examines the effect of yaw on the spectra of turbulence above and aft of the wing, in the region where fins and control surfaces are located. Prior work has shown the occurrence of narrowband velocity fluctuations in this region for most combat aircraft models, including those with twin fins. Fin vibration and damage has been traced to excitation by such narrowband fluctuations. The narrowband fluctuations themselves have been traced to the wing surface. The issue in this paper is the effect of yaw on these fluctuations, as well as on the aerodynamic loads on a wing, without including the perturbations due to the airframe.

The interest in flying cars comes with the question of characterizing aerodynamic loads on shapes that go beyond traditional aircraft shapes. When carried as slung loads under aircraft, vehicles can encounter severe aerodynamic loads, which may also cause them to go into divergent oscillations that can threaten the vehicle and aircraft. Slung loads can encounter the wind at arbitrary attitudes. Flight test certification for every vehicle-aircraft combination is prohibitive. Characterizing the aerodynamic loads with sufficient resolution for use in dynamic simulation, has in the past been extremely arduous. Sharp changes that drive instabilities arise over small ranges of yaw and pitch. With the Continuous Rotation technique developed by our group, aerodynamic load characterization is viable and efficient. With two well-chosen attitude sweeps and appropriate transformations, the entire 6-DOF load map can be obtained, for several rates.

At high angles of attack, the flow over a swept wing generates counter-rotating vortical features. These features can amplify into a nearly sinusoidal fluctuation of velocity components. The result is excitation of twin-fin buffeting, driven at clearly predictable frequencies, or at nearby lock-in frequencies of the fin structure. This is distinct from the traditional model of fin buffeting as a structural resonant response to broadband, large-amplitude excitation from vortex core bursting. Hot-film anemometry was conducted ahead of the vertical fins of a 1:48 scale model of the F-35B aircraft, in the angle of attack range between 18 and 30 degrees. Auto spectral density functions from these data showed a sharp spectral peak in the flow ahead of the fins for angles of attack between 20 and 28 degrees. Small fences placed on the top surface of the wing eliminated the spectral peak, leaving only a broadband turbulent spectrum.

Loads slung under aircraft can go into divergent oscillations coupling multiple degrees of freedom. Predicting the highest safe flight speed for a vehicle-load combination is a critical challenge, both for military missions over hostile areas, and for evacuation/rescue operations. The primary difficulty was that of obtaining well-resolved airload maps covering the arbitrary attitudes that a slung load may take. High speed rotorcraft using tilting rotors and co-axial rotors can fly at speeds that imply high dynamic pressure, making aerodynamic loads significant even on very dense loads such as armored vehicles, artillery weapons, and ammunition. The Continuous Rotation method demonstrated in our prior work enables routine prediction of divergence speeds. We build on prior work to explore the prediction of divergence speed for practical configurations such as military vehicles, which often have complex bluff body shapes.

We present a new interval-based formulation for the static analysis of plane stress/strain problems with uncertain parameters in load, material and geometry. We exploit the Interval Finite Element Method (IFEM) to model uncertainties in the system. Overestimation due to dependency among interval variables is reduced using a new decomposition strategy for the structural stiffness matrix and the nodal equivalent load vector. Primary and derived quantities follow from minimization of the total energy and they are solved simultaneously and with the same accuracy by means of Lagrangian multipliers. Two different element assembly strategies are introduced in the formulation: one is Element-by-Element, and the other resembles conventional assembly. In addition, we implement a new variant of the interval iterative enclosure method to obtain outer and inner solutions. Numerical examples show that the proposed interval approach guarantees to enclose the exact system response.

This work contributes to the understanding of physical mechanisms that control flashback, or more appropriately combustion recession, in diesel sprays. A large dataset, comprising many fuels, injection pressures, ambient temperatures, ambient oxygen concentrations, ambient densities, and nozzle diameters is used to explore experimental trends for the behavior of combustion recession. Then, a reduced-order model, capable of modeling non-reacting and reacting conditions, is used to help interpret the experimental trends. Finally, the reduced-order model is used to predict how a controlled ramp-down rate-of-injection can enhance the likelihood of combustion recession for conditions that would not normally exhibit combustion recession. In general, fuel, ambient conditions, and the end-of-injection transient determine the success or failure of combustion recession.

Numerous studies have pointed out the growing need to assess the availability of water sources in numerous regions around the world as future forecasts suggest that water demands will increase significantly while freshwater resources are being depleted. In this paper, we highlight the difference between water use versus consumption and analyze the life-cycle water consumption of a car from material extraction through production, use, and final disposition/end of life and determine a car's water footprint using data from the EcoInvent database as well as data collected from literature sources. Although water use is typically metered at the factory level, water consumption (i.e., water lost through evaporation and/or incorporation into a material, part, and/or product) is much harder to quantify. As shown in this paper, the difference can be an order of magnitude or more.

In this paper, we quantify several environmental benefits associated with using ultra fine scrap tire rubber powders in virgin and recycled rubber and plastics compounds. Specifically, we will analyze the savings in oil extraction and rubber production in comparison to the rubber powder production using cryogenic grinding. The analysis uses first hand factory data provided by a rubber powder producer. As will be shown, even though cryogenic nitrogen requires production and use of liquid nitrogen, there is still a net environmental benefit in terms of energy use and greenhouse gas emissions.

This paper looks at a method for decomposing a manufactured product into what is called an “activity space.” The method uses an activity based costing scheme to structure the model and organize the information. It is discussed how the activity space is used to perform sustainability assessments of a manufactured product and the manufacturing process from different viewpoints and perspectives. The way in which the activity space is used to perform an assessment from several viewpoints is discussed.

This article begins by describing the need for a new method and tool for performing a sustainability assessment for manufacturing processes and systems. A brief literature survey is done to highlight the major existing methods and tools, their function, and their shortcomings. The article goes on to describe the general approach of the method before describing a computer aided tool that has been developed to implement the method. The article concludes with a walk through of a generic use case that describes where such a method would be useful and how such a tool would be implemented.

This paper outlines the design of a part transport and loading/unloading automation system for a cylindrical die thread roller, enumerating many of the design decisions encountered. Specifically, a transport tray system is proposed and prototyped as a benchmark for factory automation. Details of an automation system which will interface with the proposed transport tray system are discussed. A gripping system which accommodates a wide variety of fastener head styles is developed to work in conjunction with the tray concept, and prototyped with favorable results.

In this paper, we describe our work and experiences with integrating environmental and economic performance monitoring in a production facility of Interface Flooring Systems, Inc. The objective of the work is to create a ‘dashboard’ that integrates environmental and economic monitoring and assessment of manufacturing processes, and provides engineers and managers an easy to use tool for obtaining valid, comparable assessment results that can be used to direct attention towards necessary changes. To this purpose, we build upon existing and familiar cost management principles, in particular Activity-Based Costing and Management (ABC&ABM), and we extend those into environmental management in order to obtain a combined economic and environmental performance measurement framework (called Activity-Based Cost and Environmental Management).

The design of hypersonic vehicles is influenced by tightly coupled interactions between aerodynamics, propulsion, and structures. Therefore, in the conceptual design phases, the identification and mitigation of potential problem areas and disciplinary interrelations are critical. Although the multidisciplinary character of hypersonic designs is well known, research in hypersonics is primarily focused on the isolated disciplines with side notes on the interactions. The designer has to integrate all the disciplinary information and create a successful system. This integration is a tedious and elaborate process involving time-consuming iterations. This paper proposes a new approach and entails the creation of Response Surface Equations from the various constituent disciplines considered. This method allows to quickly assess the implication of design decisions at the top level using the multiple disciplinary meta-models.