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Development of a test rig to evaluate the performance of Front-End Accessory Drive systems

VIBROACUSTICA-Celso Kenzo Takemori, Diego Wilian da Silva, Edmar Baars
ZEN S.A. Indústria Metalúrgica-Alvaro Canto Michelotti, Lucas Figueiro Berto, Pedro Palma Pastorelli, Andre Francioso Ferreira
  • Technical Paper
  • 2019-36-0296
Published 2020-01-13 by SAE International in United States
The increased adoption of downsized engines along with higher electrical demand is generating a challenge to the Front-End Accessory Drive (FEAD) system functioning and validation. One alternative to speed up the validation of potential design solutions is the in-vehicle experimental tests approach. Nevertheless, experimental data collection during in-vehicle FEAD evaluation imposes some challenges due to, for instance, packaging space constraints and sample rate required to capture the dynamic events during vehicle operation, among others. In order to overcome this limitation, the objective of this research is focused in the development of a customized test rig that emulates FEAD layout of an actual automobile in a simulated operating condition. This equipment could contribute in research studies focusing in critical performance parameters, allowing complete data acquisition and evaluation of potential design trade-offs that could maximize overall performance of the system, as the test rig could also allow the study of the impact of different layouts or operational configurations in the overall system efficiency. Therefore, the test rig design intent is to have a configurable layout that can…
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Expansion of external EGR effective region and influence of dilution on boosted operation of a downsized turbocharged GDI engine

Brunel University London, Centre of Advanced Powertrain and-Ray Shimura, Hua Zhao, Xinyan Wang
  • Technical Paper
  • 2019-01-2252
Published 2019-12-19 by SAE International in United States
Engine downsizing is an effective technology to lower automotive CO2 emissions. However, the high load low speed regions are plagued with knocking combustion that are usually overcome by retarding the ignition. This interferes with the efficiency gains due to very late combustion. This paper reports the use of Exhaust Gas Recirculation (EGR) on a Ford Ecoboost 1l downsized gasoline turbocharged direct injection (GTDI) engine to improve efficiency by optimising combustion phasing unlocked by the improved knock resistance with EGR dilution. Further ignition system upgrades are tested for impact towards further efficiency improvements. 75mJ (standard) and 120mJ (high energy) ignition systems were compared. The experimental results showed that the brake specific fuel consumption (BSFC) can be improved by 5.6% with EGR dilution at 25%. When considering combined effects of EGR and high energy ignition upon engine fuel economy, the BSFC gain improves to 7.9%.
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Conceptual Design, Material, and Structural Optimization of a Naval Fighter Nose Landing Gear for the Estimated Static Loads

SAE International Journal of Aerospace

Anna University Chennai - Regional Office Tiruchirappalli, India-Swagata Paul, K. Suresh
Senior Grade Assistant Professor, India-C. Senthilkumar
  • Journal Article
  • 01-12-02-0009
Published 2019-12-13 by SAE International in United States
The Naval Nose Landing Gear (NLG) structural assembly consists of components with complex structural geometry and critical functionalities. The landing gear components are subjected to high static and dynamic loads, so they must be appropriately designed, dimensioned, and made by materials with mechanical characteristics that meet high strength, stiffness, and less weight requirements. This article contributes to the shape, size, and material optimization for the NLG of a supersonic naval aircraft for the estimated static loads. The estimated modal frequency values of the NLG assembly using Finite Element Analysis (FEA) software were compared with available Ground Vibration Test data of an aircraft to literally prove the accuracy and suitability of finite element (FE) model that can be used for any further analysis. Static structural analysis was performed for the critical landing load cases, and the Reserve Factor (RF) values of the landing gear components were calculated to determine their static strength capacity. Iterations including shape, size, and material optimization were done in the NLG to reduce the mass with the required strength characteristics.
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ACeDrive consortium plans more-efficient EV powertrain

Automotive Engineering: November/December 2019

Stuart Birch
  • Magazine Article
  • 19AUTP11_03
Published 2019-11-01 by SAE International in United States

Led by GKN, the ACeDrive consortium is developing lighter and more-efficient EV propulsion, targeting volume production in 2023.

It's called ACeDrive, which may sound innocuous for an auto-industry project. But the consortium that formed it has announced that it seeks to develop the world's lightest and most efficient volume electric vehicle (EV) powertrain. Involving two major suppliers, a research university and the UK government-backed Advanced Propulsion Centre (APC), the aggressive targets for the ACeDrive (Advanced Cooling and Control of high speed e-Drive) include a 25% reduction in cost, a 25% reduction in packaging size and a 20% reduction in weight combined to deliver a 10% increase in efficiency.

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Design and Fabrication of CFRP Wheel Centre for FSAE Race-Car

VIT-Sangeet Aggarwal, Renold Elsen
Published 2019-10-11 by SAE International in United States
In this work, a Carbon Fibre Reinforced Polymer (CFRP) Wheel Centre (WC) is designed targeting key parameters such as reduced un-sprung mass and lower rotational inertia in vehicle dynamics. A Keizer Aluminium Wheel Centre was used by the team previously and it weighed around 1.8 Kg. Designing of CFRP Wheel Centre was based on previously used Keizer Aluminium wheel centre considering the design constraints such as distance between hub and wheel assembly. This was done to ensure the same trackwidth within the Formula Student rules. Initially, the Finite Element Analysis (FEA) was carried out for the Keizer Aluminium wheel centre and the results were analysed. For the same design CFRP material was used and the result was found out to be promising with a wheel centre weight of 1.3 Kg. Further to improve the performance and weight reduction, FEA was done to design a 38 layered CFRP wheel centre giving utmost priority to ease of manufacturability and safe design. After manufacturing, the CFRP wheel centre weighed 950g and was implemented on PRV17 (Pravega Racing’s FSAE…
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Performance Evaluation of an Electric Vehicle with Multiple Electric Machines for Increased Overall Drive Train Efficiency

University of Ljubljana-Mario Vukotić, Damijan Miljavec
University of Rome Niccolò Cusano and S.C.I.R.E. Consortium-Laura Tribioli, Daniele Chiappini
Published 2019-10-07 by SAE International in United States
Proposed solutions for electric vehicles range from the simple single-motor drive coupled to one axle through a mechanical differential, to more complex solutions, such as four in-wheel motors, which ask for electronic torque vectoring. Main reasons for having more than one electric machine are: reduction of the rated power of each motor, which most likely leads to simplification and cost reduction of all the electric drive components; increased reliability of the overall traction system, enhancing fault tolerance ability; increase of the degrees of freedom which allows for control strategy optimization and efficiency improvement. In particular, electrical machines efficiency generally peaks at around 75% of load and this usually leads to machine downsizing to avoid operation in low efficiency regions. The same output performance can be achieved by using two or more electrical machines, rather than only one, of smaller size and running them at unequal load - one of the machines at higher load and the other(s) at lower load.In this paper, the performance of an electric vehicle with multiple electric machines is analyzed to…
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Axial Flow Turbine Concept for Conventional and e-Turbocharging

Brunel University-Apostolos Pesyridis
Universita di Napoli Federico II-Alessandro Cappiello, Raffaele Tuccillo, Maria Cristina Cameretti
Published 2019-09-09 by SAE International in United States
Engine downsizing has established itself as one of the most successful strategies to reduce fuel consumption and pollutant emissions in the automotive field. To this regard, a major role is played by turbocharging, which allows an increase in engine power density, so reducing engine size and weight. However, the need for turbocharging imposes some issues to be solved. In the attempt of mitigating turbo lag and poor low-end torque, many solutions have been presented in the open literature so far, such as: low inertia turbine wheels and variable geometry turbines; or even more complex concepts such as twin turbo and electrically assisted turbochargers. None of them appears as definitive, though.As a possible way of reducing turbine rotor inertia, and so the turbo lag, also the change of turbine layout has been investigated, and it revealed itself to be a viable option, leading to the use of mixed-flow turbines. Only recently, the use of axial-flow turbines, with the aim of reducing rotor inertia, has been proposed as well.The current paper documents a case study involving the…
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Valve Flow Coefficients under Engine Operation Conditions: Piston Influence and Flow Pulsation

FKFS-Michael Grill
University of Stuttgart-Sven Fasse, Michael Bargende
Published 2019-09-09 by SAE International in United States
Engine valve flow coefficients are used to describe the flow throughput performance of engine valve/port designs, and to model gas exchange in 0D/1D engine simulation. Valve flow coefficients are normally determined at a stationary flow test bench, separately for intake and exhaust side, in the absence of the piston. However, engine operation differs from this setup; i. a. the piston might interact with valve flow around scavenging top dead center, and instead of steady boundary conditions, valve flow is nearly always subjected to pressure pulsations, due to pressure wave reflections within the gas exchange ports. In this work the influences of piston position and flow pulsation on valve flow coefficients are investigated for different SI engine geometries by means of 3D CFD and measurements at an enhanced flow test bench. In the past, most research work on valve flow coefficients left aside possible piston influence and, for dynamic boundary conditions, it largely omitted subtraction of the gas inertia effects, which are already covered by 1D simulation. In this work, concerning piston influence, various valve overlap…
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Model Verification of CAE with NVH-Test Acting on Downsized Car Engines

NVH-testing Powertrain-Janos Ribarits
Volvo Cars, Engine Vibrations CAE-Urban Rönnqvist
Published 2019-06-05 by SAE International in United States
Today’s trend of combustion engine development for cars is characterized with; high torque, low engine speed, low weight, high degree of cyclic irregularity, low excitation frequency due to fewer cylinders active e.g. 4-cylinder or less.This implies in respect of vibrations that it is crucial to control powertrain rigid body modes and place these were they cannot be reached and induced by the low exciting harmonic frequencies for low engine speeds or idling. It is also important to control the overall flexible vibration modes.A mathematical CAE model is created in simulation software AVL-EXCITE in order to handle the vibration phenomenon as a first step. But it is absolutely necessary to “verify” these models with real measurements in respect of NVH and if needed upgrade the CAE model if there are detected deviations. The NVH-test is done with testing tool DEWESoft.The purpose of below paper is to do model verification on a concrete example in respect of powertrain vibrations. Volvo Cars in-line 4-cylinder VEA diesel engine in rig installation is the object for the paper of model…
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Vibro-Acoustic Analysis for Modeling Propeller Shaft Liner Material

General Motors-Rajith R. Jayaratne, Yu Liu, Mark Gehringer, Jeff Rayce, Wallace Hill
Published 2019-06-05 by SAE International in United States
In recent truck applications, single-piece large-diameter propshafts, in lieu of two-piece propshafts, have become more prevalent to reduce cost and mass. These large-diameter props, however, amplify driveline radiated noise. The challenge presented is to optimize prop shaft modal tuning to achieve acceptable radiated noise levels. Historically, CAE methods and capabilities have not been able to accurately predict propshaft airborne noise making it impossible to cascade subsystem noise requirements needed to achieve desired vehicle level performance. As a result, late and costly changes can be needed to make a given vehicle commercially acceptable for N&V performance prior to launch.This paper will cover the development of a two-step CAE method to predict modal characteristics and airborne noise sensitivities of large-diameter single piece aluminum propshafts fitted with different liner treatments. The first step is the use of a traditional CAE software to calculate prop surface response. The second step is a boundary element simulation to calculate prop surface radiated noise under the excitation obtained from the first step. Finally, acceleration and acoustic test data are presented to assess…
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