Criteria

Text:
Display:

Results

Viewing 1 to 30 of 5190
2017-03-28
Technical Paper
2017-01-0261
Randolph Jones, Robert Marinier III, Frank Koss, Robert Bechtel, John A. Sauter
When evaluating new vehicle designs, modeling and simulation offer techniques to predict parameters such as maximum speed, fuel efficiency, turning radius, and the like. However, the measure of greatest interest is the likelihood of mission success. One approach to assessing the likelihood of mission success in simulation is to build behavior models, operating at the human decision-making level, that can execute realistic missions in simulation. This approach makes it possible to not only measure changes in mission success rates, but also to analyze the causes of mission failures. Layering behavior modeling and simulation on underlying models of equipment and components enables measurement of more conventional parameters such as time, fuel efficiency under realistic conditions, distance traveled, equipment used, and survivability.
2017-03-28
Technical Paper
2017-01-1225
Jayaraman Krishnasamy, Martin Hosek
An advanced electric motor with hybrid-field topology has been developed for automotive traction applications. Departing from the conventional radial- and axial-field designs, the hybrid-field motor features three-dimensional magnetic flux paths in a geometry that maximizes the effective volume for magnetic flux flow. The three-dimensional flux paths are enabled by an isotropic soft magnetic material, which has been engineered to replace conventional laminated winding cores with solid isotropic components. The material is produced by a novel additive-manufacturing process based on spray forming. The paper introduces the spray-forming process for motor stator components and presents a conceptual design of the traction motor developed around them, including the motor topology, stator construction and rotor construction. The stator features a spray-formed core with three-dimensional magnetic flux paths, high-density windings and direct liquid cooling.
2017-03-28
Technical Paper
2017-01-0264
Venkatesh Babu, Ravi Thyagarajan, Jaisankar Ramalingam
In this paper, the capability of three methods of modelling detonation of high explosives (HE) buried in soil viz., (1) coupled discrete element & particle gas methods (DEM-PGM) (2) Structured - Arbitrary Lagrangian-Eulerian (S-ALE), and (3) Arbitrary Lagrangian-Eulerian (ALE),are investigated. The ALE method of modeling the effects of buried charges in soil is well known and widely used in blast simulations today Due to high computational costs, inconsistent robustness and long run times, alternate modeling methods such as Smoothed Particle Hydrodynamics (SPH) and DEM are gaining more traction. In all these methods, accuracy of the analysis relies not only on the fidelity of the soil and high explosive models but also on the robustness of fluid-structure interaction. These high-fidelity models are also useful in generating fast running models (FRM) useful for rapid generation of blast simulation results of acceptable accuracy.
2017-03-28
Technical Paper
2017-01-0260
Yuanying Wang, Heath Hofmann, Denise Rizzo, Scott Shurin
The increasing electrification of military vehicles is also increasing the need for accurate models of electric motors and generators for use in powertrain design. In particular, there is a strong need to accurately model the internal temperatures of these machines. Thus, an accurate yet computationally-efficient thermal model is required. In previous work, a technique capable of dramatically reducing the order of a 3-dimensional finite-element (FE) thermal conduction model was developed. The developed model has acceptable accuracy but is orders of magnitude faster than the FE model. This new model was validated by a locked-rotor test with close agreement, but the results are unsatisfactory when the rotor is spinning, since the resulting heat convection behavior is not precisely modeled. This paper will present a computationally-efficient model of heat convection due to air circulation produced by rotor motion.
2017-03-28
Technical Paper
2017-01-0250
Jizhou Zhang, Jianhua Zhou, Mian LI, Min Xu
To improve the system performance, precision manufacturing is required for production of the internal combustion engines (ICEs), a typical complex nonlinear system. Previous studies show that tolerances of critical dimensions have significant impacts on the engine performance. Among many critical factors, friction loss is one of the most important ones that affect the output performance of ICEs. It is necessary to recognize and control the tolerances which affect the friction loss. Of all the friction pairs for the engine, it is observed that the piston-cylinder friction pair and the bearing system take up nearly 70% of the total friction loss. In this work a novel multi-objective tolerance design optimization problem considering two friction systems mentioned above is proposed and solved. First two separated simulation models, the piston-cylinder and the bearing are built using AVL Excite Piston & Ring® and AVL Excite Power Unit®, respectively.
2017-03-28
Technical Paper
2017-01-0903
Sarp Mamikoglu, Jelena Andric, Petter Dahlander
Many technological developments in automobile powertrains have been implemented in order to increase efficiency and comply with emission regulations. Although most of these technologies show promising results in official fuel economy tests, their benefits in real driving conditions and real driving emissions can vary significantly, since driving profiles of many drivers are different than the official driving cycles. Therefore, it is important to assess these technologies under different driving conditions and this paper aims to offer an overall perspective, with a numerical study in simulations. The simulations are carried out on a compact passenger car model with eight powertrain configurations including: a naturally aspirated spark ignition engine, a start-stop system, a downsized engine with a turbocharger, a Miller cycle engine, cylinder deactivation, turbocharged downsized Miller engine, a parallel hybrid electric vehicle powertrain and an electric vehicle powertrain.
2017-03-28
Technical Paper
2017-01-0182
Gautam Peri, Saravanan Sambandan, S. Sathish Kumar
The intended primary objective of a passenger vehicle air conditioning system is to ensure thermal comfort to the passengers seated inside at all prevailing conditions. Presently 1D analysis plays a major role in determining the conformation of the selected system to achieve the desired results. Virtual analysis thus saves a lot of time, cost and effort in predicting the system performance in the initial development phase of the vehicle HVAC systems. A variety of parameters play an important role in achieving the above thermal comfort. In order to optimize the simulation, predicting the duct losses and cabin interior temperatures plays a vital role. Physical and geometrical parameters of the cabin are accurately modelled by considering all the parameters such as glass and sheet metal surfaces, air gaps, solar angles, solar intensity, instrumentation panel, firewall etc.
2017-03-28
Technical Paper
2017-01-1141
Bashar Alzuwayer, Robert Prucka, Imtiaz Haque, Paul Venhovens
Abstract Fuel economy regulations have forced the automotive industry to implement transmissions with an increased number of gears and reduced parasitic losses. The objective of this research is to develop a high fidelity and a computationally efficient model of an automatic transmission, this model should be suitable for controller development purposes. The transmission under investigation features a combination of positive clutches (interlocking dog clutches) and conventional wet clutches. Simulation models for the torque converter, lock-up clutch, transmission gear train, interlocking dog clutches, wet clutches, hydraulic control valves and circuits were developed and integrated with a 1-D vehicle road load model. The integrated powertrain system model was calibrated using measurements from real-world driving conditions. Unknown model parameters, such as clutch pack clearances, compliances, hydraulic orifice diameters and clutch preloads were estimated and calibrated.
2017-03-28
Journal Article
2017-01-0899
Paul Dekraker, John Kargul, Andrew Moskalik, Kevin Newman, Mark Doorlag, Daniel Barba
The Environmental Protection Agency’s (EPA’s) Advanced Light-Duty Powertrain and Hybrid Analysis (ALPHA) tool was created to estimate greenhouse gas (GHG) emissions from light-duty vehicles. ALPHA is a physics-based, forward-looking, full vehicle computer simulation capable of analyzing various vehicle types with different powertrain technologies, showing realistic vehicle behavior, and auditing of internal energy flows in the model. In preparation for the midterm evaluation (MTE) of the 2017-2025 light-duty GHG emissions rule, ALPHA has been updated utilizing using newly acquired data from model year 2013-2015 engines and vehicles.
2017-03-28
Journal Article
2017-01-0267
Tomasz Haupt, Gregory Henley, Angela Card, Michael S. Mazzola, Matthew Doude, Scott Shurin, Christopher Goodin
Pending OPSEC review
2017-03-28
Journal Article
2017-01-0518
Sebastian Hann, Lukas Urban, Michael Grill, Michael Bargende
Abstract Since 0D/1D-simulations of natural gas spark ignition engines use model theories similar to gasoline engines, the impact of changing fuel characteristics needs to be taken into consideration in order to obtain results of higher quality. For this goal, this paper proposes some approaches that consider the influence of binary fuel mixtures such as methane with up to 40 mol-% of ethane, propane, n-butane or hydrogen on laminar flame speed and knock behavior. To quantify these influences, reaction kinetics calculations are carried out in a wide range of the engine operation conditions. Obtained results are used to update and extend existing sub-models. The model quality is validated by comparing measured burn rates with simulation results. The benefit of the new sub-models are utilized by predicting the influence the fuel takes on engine operating limits in terms of knocking and lean misfire limits, the latter being determined by using a cycle-to-cycle variation model.
2017-02-08
WIP Standard
AIR6387
The development of future more-and full-electric aircraft concepts has significantly impacted aircraft electric power system (EPS) design. Finalizing the EPS architectures involves extensive modeling and simulation activities to ensure the required characteristics of the entire EPS prior to the physical implementation. Hence, the development of accurate, effective and computational time-saving simulation models is of great importance. Correspondingly, there is a need to establish an EPS-specific modeling and simulations common framework to ensure effective and accurate solutions to the problems addressed. The document continues a series of AE-7M documents specific for aircraft electrical systems aiming to establish such a framework (the series has started with AIR 6326 "Aircraft Electrical Power Systems. Modeling and Simulation. Definitions" issued in August, 2015).
2017-01-26
Magazine
Open Standard Middleware Enables New HPEC Solutions Cooling Your Embedded System What Can Your Open Standard Architecture Handle? Evaluating Key Certification Aspects of Multicore Platforms for Safety Critical Avionics Applications Simulating and Analyzing Flow for an Air-to-Air Refueling System The Ins and Outs of Spaceflight Passive Components and Assemblies Development of High Quality 4H-SiC Thick Epitaxy for Reliable High Power Electronics Using Halogenated Precursors Silicon Based Mid-Infrared SiGeSn Heterostructure Emitters and Detectors Reconfigurable Electronics and Non-Volatile Memory Research Energy-Filtered Tunnel Transistor: A New Device Concept Toward Extremely Low Energy Consumption Electronics
2017-01-12
WIP Standard
ARP5765B
This SAE Aerospace Recommended Practice (ARP) defines a means of assessing the credibility of computer models of aircraft seating systems used to simulate dynamic impact conditions set forth in Federal Regulations §14 CFR Part 23.562, 25.562, 27.562, and 29.562. The ARP is applicable to lumped mass and detailed finite element seat models. This includes specifications and performance criteria for aviation specific virtual anthropomorphic test devices (v-ATDs). A methodology to evaluate the degree of correlation between a seat model and dynamic impact tests is recommended. This ARP also provides testing and modeling best practices specific to support the implementation of analytical models of aircraft seat systems. Supporting information within this document includes procedures for the quantitative comparison of test and simulation results, as well as test reports for data generated to support the development of v-ATDs and a sample v-ATD calibration report.
2017-01-10
Technical Paper
2017-26-0238
Abhijit Kumbhar, Jagannath M Paranjpe, Nagesh Karanth
Abstract New process development of forging component requires in-depth knowledge and experience related to the process. Also it requires number of physical trials to arrive at optimum process and initial billet dimensions. With the help of reliable computer simulation tool, it is possible to optimize the complete forging process and billet dimensions. Simulation provides much more insight about the process and possible forging defects. This saves considerable time and money. This paper describes about a complete forging process designed for a complex component. With the help of metal forming simulation software, complete forging process was simulated and optimized. Forging defects were removed during optimization of the process. Billet weight optimization was also carried out. Deciding the preforming shape of the billet was the main challenge. An innovative pre-forging shape was arrived which resulted in eliminating one process stage.
2016-12-01
Magazine
Additive Manufacturing How 3D Printing Will Transform the A&D Support Chain Advances in Lightweight Electronics Protection Conformal Coatings Increase Reliability of Aerospace and Military Assemblies Powering Outer Space An In-Depth Look at Aerospace Battery Technology Using High Bandwidth Oscilloscopes to Analyze Radar and Electronic Warfare Systems Bio-inspired Airborne Infrastructure Reconfiguration (BioAIR) EMI Analysis Software Helps Telescope Group Simulate RFI Mitigation Epitaxial Growth of Rhenium with Sputtering Processing and Characterization of Polycrystalline YAG (Yttrium Aluminum Garnet) Core-Clad Fibers Multi-Scale Analysis of Deformation and Failure in Polycrystalline Titanium Alloys Under High Strain Rates Abrasion Testing of Products Containing Nanomaterials Spectrum Fatigue of 7075-T651 Aluminum Alloy under Overloading and Underloading
2016-11-09
Book
This title includes the technical papers developed for the 2016 Stapp Car Crash Conference, the premier forum for the presentation of research in impact biomechanics, human injury tolerance, and related fields, advancing the knowledge of land-vehicle crash injury protection. The conference provides an opportunity to participate in open discussion about the causes and mechanisms of injury, experimental methods and tools for use in impact biomechanics research, and the development of new concepts for reducing injuries and fatalities in automobile crashes. The topics covered this year include: • Head/brain biomechanics • Thorax, spine, and pelvis biomechanics • Foot-Ankle Biomechanics • Injury and effect of directional impacts • Pedestrian and cyclist injury factors and testing • Commercial truck and pedestrian accidents factors and testing
2016-10-25
Technical Paper
2016-36-0123
Fernando Ulhôa, Marcos Campolina, Gustavo Portilho, Rogério Amorim
Abstract This work consists of a computational simulation of a high performance ethanol engine to race Formula SAE Brazil. This study was conducted in order to reduce the performance losses caused by the mandatory usage of an air restrictor in the intake system. It started by redesigning the entire intake system of a Honda 600cc engine, selected by the GTR FSAE Team for this competition. The Ricardo WAVE software was used to developed a base engine model and their results were compared with the initial data (factory default). Then, a new intake system model based on the proposed changes was simulated. After observing the effects that the air restrictor could make to the performance, some actions were taken to minimize them. Finally, an engine fuel conversion to Brazilian Ethanol was carried out. The final results showed a feasible power improvement around 6% when compared with the gasoline engine with air restrictor.
2016-10-25
Technical Paper
2016-36-0136
Cecília Souto Lage, José Ricardo Sodré
Abstract The demand for optimization of engine design and operating conditions in order to achieve fuel economy and attend strict emission legislation leads to development of engine simulation tools. The virtual testing tools provide results in a short time with low costs, and enable larger variation on the design and operational conditions. Nowadays engine simulation is performed by commercial software or open source models. In one hand, commercial software are able to simulate complex quasi or multi-dimensional models and have an intuitive interface with the user. The model validation can be extremely difficult since specific model details are not known. In the other hand, the open source models are appropriate for thermodynamic models capable of predicting in-cylinder data and pollutant emissions. The validation process in this type of tool is usually simple since all assumptions of modeling are known.
2016-10-25
Technical Paper
2016-36-0184
Eduardo Domingo Morales
Abstract The twist-beam suspension is widely used in vehicles due to the simplicity of its construction, less occupied space and its low manufacturing cost in comparison with multi-link suspension. The difficulties related to the design of a twist-beam axle concern the large number of possible configurations for twist-beam profile and the stiffness adjustment of axle beam and suspension arms. However, design process can be done with the aid of multibody dynamics simulations, by testing several configurations in a virtual way. In this work, a simplified twist-beam suspension model is studied, and the influence of variation of its parameters is analyzed in its elastokinematics behavior and in handling performance of a vehicle.
2016-10-25
Technical Paper
2016-36-0182
Eduardo Domingo Morales
Abstract There are many variables involved in the design of a front suspension, such as hardpoints' coordinates, steering geometry or even an anti-roll bar, which could make design difficult and time consuming. The MacPherson strut, due to the simplicity of its construction, less occupied space and low manufacturing cost, is widely used in vehicles in contrast to double wishbone and multi-link suspensions. Although its tuning process still demands time, it can be done with the aid of multibody dynamics simulations, by testing several configurations in a virtual way. In this work, a front suspension model with MacPherson strut is studied, so that the influence of variation of its parameters is analyzed in its elastokinematics behavior and in handling performance of a vehicle.
2016-10-24
Event
The session covers advances in the development and application of models and tools involved in multi-dimensional engine modeling: advances in chemical kinetics, combustion and spray modeling, turbulence, heat transfer, mesh generation, and approaches targeting improved computational efficiency. Papers employing multi-dimensional modeling to gain a deeper understanding of processes related to turbulent transport, transient phenomena, and chemically reacting, two-phase flows are also encouraged.
2016-10-17
Technical Paper
2016-01-2235
Prithwish Kundu, Riccardo Scarcelli, Sibendu Som, Andrew Ickes, Yan Wang, John Kiedaisch, M Rajkumar
Abstract Heat loss through wall boundaries play a dominant role in the overall performance and efficiency of internal combustion engines. Typical engine simulations use constant temperature wall boundary conditions [1, 2, 3]. These boundary conditions cannot be estimated accurately from experiments due to the complexities involved with engine combustion. As a result, they introduce a large uncertainty in engine simulations and serve as a tuning parameter. Modeling the process of heat transfer through the solid walls in an unsteady engine computational fluid dynamics (CFD) simulation can lead to the development of higher fidelity engine models. These models can be used to study the impact of heat loss on engine efficiency and explore new design methodologies that can reduce heat losses. In this work, a single cylinder diesel engine is modeled along with the solid piston coupled to the fluid domain.
2016-10-04
Event
Topics Include: Product Design and Manufacturing Integration Integrated Production Systems Software Simulation Virtual Manufacturing Direct Digital Manufacturing Analysis and Modeling Tools RFID Structural Health Monitoring/Management Advanced Metrology
2016-10-04
Event
Topics Include: Product Design and Manufacturing Integration Integrated Production Systems Software Simulation Virtual Manufacturing Direct Digital Manufacturing Analysis and Modeling Tools RFID Structural Health Monitoring/Management Advanced Metrology
Viewing 1 to 30 of 5190

Filter

  • Range:
    to:
  • Year: