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SAE Truck & Off-Highway Engineering: February 2023

2023-02-09
Virtual powertrain development Simulation is critical for efficient product development, but proper tool selection and efficient data management are keys to success. Blue Arc amps up for EV production Shyft Group's EV subsidiary is lighting the path for the electrification of last-mile delivery vehicles as well as mobile charging solutions. Increasing connectivity in construction Jobsites look to overcome challenges posed by mixed fleets and proprietary telematics to achieve "one-dashboard" vision and increased machine utilization.
Technical Paper

Pass by Noise Analysis Method Extended for Mitigation Solution Development on Earth Moving Machinery

2021-08-31
2021-01-1071
Pass-by/exterior noise of earth moving machines (EMM) and forestry machines is becoming a focus at early product development stages. ISO 6395 (2) or EC/2000/14 (1) standards defines exterior noise test procedure for EMM. However, these standards do not provide insights for diagnosing any noise issues which may arise. The analysis challenges are posed by the moving machine and acoustic sources with respect to the stationary hemisphere target microphone on the ground and changing operating condition of sources as function of time. There is need to develop a seamless methodology to identify acoustic sources, quantify respective source strengths and rank partial contributions from each source to the total target microphone response in order to overcome the aforementioned challenges.
Technical Paper

Analytical/Numerical Methodology - Design & Development Aspects of Electric Vehicle Powertrain

2020-04-14
2020-01-1439
In recent years, customers who are looking to buy or lease a car have placed more interest in exploring electrified vehicles including Battery Electric Vehicles (BEV), Hybrid Electric Vehicles (HEV), Plug-in Hybrid Electric Vehicles (PHEV) and Fuel Cell Electric Vehicles (FCEV) as new options in the automotive market. As the recent trends suggest, this interest is likely to be solidified, and people will start buying EVs more and more. These market trends show that the internal combustion engine (ICE) drivetrain soon will be progressively replaced by the electric drive unit for passenger car applications. The electric vehicles provide positive impacts such as instant torque delivery, overall vehicle comfort, noise and vibration. They also provide local environmental benefits by reducing greenhouse gas emissions. However, there are some major complexities for EVs to overcome before completely replacing ICE vehicles.
Technical Paper

A Comparison between Different Moving Grid Techniques for the Analysis of the TCC Engine under Motored Conditions

2019-04-02
2019-01-0218
The accurate representation of Internal Combustion Engine (ICE) flows via CFD is an extremely complex task: it strongly depends on a combination of highly impacting factors, such as grid resolution (both local and global), choice of the turbulence model, numeric schemes and mesh motion technique. A well-founded choice must be made in order to avoid excessive computational cost and numerical difficulties arising from the combination of fine computational grids, high-order numeric schemes and geometrical complexity typical of ICEs. The paper focuses on the comparison between different mesh motion technologies, namely layer addition and removal, morphing/remapping and overset grids. Different grid strategies for a chosen mesh motion technology are also discussed. The performance of each mesh technology and grid strategy is evaluated in terms of accuracy and computational efficiency (stability, scalability, robustness).
Technical Paper

Acoustic Optimization of a Muffler through the Sherpa Algorithm

2019-04-02
2019-01-0844
Regulations on noise and gas emissions become more and more stringent resulting in noise abatement devices needing further engineering and optimization. Mufflers are installed at the end of powertrains to reduce the acoustic impact of the sound pressure from the engine. Such acoustic reduction is achieved through internal structures that promote destructive interference within the muffler. However, the muffler increases the backpressure downstream of the aftertreatment line, thus decreasing the engine efficiency. In the following work, an optimization workflow is presented to find the best design for a muffler geometry. The optimization is performed with the Sherpa algorithm that uses several optimization algorithms simultaneously to increase robustness and efficiency. Sherpa is implemented in an optimization tool that manages the workflow of two other software tools.
Article

Ford demos digital manufacturing tools

2019-03-26
Leveraging expansive networking and traceability, Ford has transformed its manufacturing spaces with data wellsprings that drive quality and productivity.
Technical Paper

A Study of the Half Order Modulation Control for Diesel Combustion Noise by Using Model Based Controller Design

2019-03-25
2019-01-1416
This model based investigation is carried out in order to control the half order modulation for diesel engines using by virtual calibration approach and proposes a feedback control strategy to mitigate cylinder to cylinder imbalance from asymmetric cylinders torque production. Combustion heat release analysis is performed on test data to understand the root cause of observed cylinder to cylinder pressure variations. The injected fuel variations are shown to cause the observed pressure variations between cylinders. A feedback control strategy based on measured crank shaft position is devised to control the half order modulation to balance the combustion pressure profile between cylinders. This control strategy is implemented in Simulink and is tested in closed-loop with the diesel engine model in AMESim. The closed-loop performance indicates that the half order modulation is considerably improved while having minimal impact on the fuel consumption.
Article

Boeing extends use of Siemens’ Mentor Graphics technology for electrical systems design, electronic products design, and mechanical analysis

2018-10-09
Boeing officials are expanding the company’s use of Siemens’ Mentor Graphics software as part of its Second Century Enterprise Systems (2CES) initiative, an effort to transform the company and aerospace industry to meet future challenges and achieve maximum value from end-to-end integration of supply chain, manufacturing, engineering, product support, and more. Boeing is harnessing a set of Siemens technologies to enable the next generation of design and manufacturing through increased automation and digitalization.
Magazine

MOBILITY ENGINEERING: June 2018

2018-06-01
Roadmap for future Indian passenger drone sector Internet of Vehicles: connected vehicles & data - driven solutions Development and verification of electronic braking system ECU software for commercial vehicle Engineering the Motivo Way Broad capabilities, unparalleled project diversity and an innovative culture have put this thriving California "idea factory" in high demand. Developing an alternative engine concept Ricardo's CryoPower engine leverages two unique combustion techniques for reduced emissions and fuel consumption-liquid nitrogen and split combustion. Long-haul trucking and stationary power generation will be the first beneficiaries of the technologies. Spark of genius Mazda's Skyactiv-X-the nexus of gasoline and diesel tech-remains on track for 2019 production. We test-drive recent prototypes to check development status. Plain bearings for aerospace applications
Magazine

SAE Truck & Off-Highway Engineering: April 2018

2018-04-05
Connectivity takes center stage Telematic links have become the norm, helping fleet owners and operators improve efficiency and letting OEMs predict component failures. More power, less noise, fewer emissions These key attributes drive development of new generators both big and small. TARDEC pursues advanced power generation U.S. Army, GM collaborate on fuel-cell-generated electricity to power the vehicle's propulsion system and onboard electronics, while providing off-vehicle power via an Exportable Power Take-Off unit. Developing an alternative engine concept Ricardo's CryoPower engine leverages two unique combustion techniques for reduced emissions and fuel consumption-liquid nitrogen and split combustion. Long-haul trucking and stationary power generation will be the first beneficiaries of the technologies. Technology time-warp The road to autonomous driving has been under construction for decades, as showcased by SAE's Mobility History Committee at the 2018 WCX in Detroit.
Technical Paper

Development of Traction Fluid Property Tables for a Toroidal CVT Multi-Body Simulation

2018-04-03
2018-01-1061
A toroidal variator is the core part of an advanced Continuously Variable Transmission (CVT) design. Knowing its behavior and internal forces is key to defining the operational conditions of the transmission. To maintain a steady-state speed ratio, or to accurately and efficiently move between speed ratios, optimal trunnion control force is required. The unique design of the toroidal CVT makes the design very sensitive to trunnion positioning and force transients. Analytical understanding of the mechanism response is critical to toroidal variator controller design. A critical feature of the toroidal CVT simulation is representation of the friction forces in the disk-roller contact. This effect is important to the mechanism torque capacity and efficiency.
Technical Paper

Chemistry-Based Laminar Flame Speed Correlations for a Wide Range of Engine Conditions for Iso-Octane, n-Heptane, Toluene and Gasoline Surrogate Fuels

2017-10-08
2017-01-2190
CFD simulations of reacting flows are fundamental investigation tools used to predict combustion behaviour and pollutants formation in modern internal combustion engines. Focusing on spark-ignited units, most of the flamelet-based combustion models adopted in current simulations use the fuel/air/residual laminar flame propagation speed as a background to predict the turbulent flame speed. This, in turn, is a fundamental requirement to model the effective burn rate. A consolidated approach in engine combustion simulations relies on the adoption of empirical correlations for laminar flame speed, which are derived from fitting of combustion experiments. However, these last are conducted at pressure and temperature ranges largely different from those encountered in engines: for this reason, correlation extrapolation at engine conditions is inevitably accepted. As a consequence, relevant differences between proposed correlations emerge even for the same fuel and conditions.
Magazine

SAE Truck & Off-Highway Engineering: August 2017

2017-08-03
Collaborating on diesel emission control Stringent fuel-efficiency and criteria-pollutant standards call for new combustion strategies. The SwRI-led Advanced Combustion Catalyst and Aftertreatment Technologies consortium reinvents existing technologies and experiments with new catalysts to meet standards. More intelligence equals more efficiency, enhanced functionality Advanced systems require renewed focus on architectures, processors, sensors and networks. Appraising the potential for platooning in the U.S. Researchers from the National Renewable Energy Laboratory perform statistical analysis based on a large collection of real-world U.S. truck usage data to estimate the fraction of total miles that are technically suitable for platooning. Connected commercial vehicles bring cybersecurity to the fore Connectivity, automation and electrification will largely drive vehicle developments in the coming years, according to experts presenting at the revamped SAE COMVEC 17.
Technical Paper

Separation of Combustion and Mechanical Noise Using Wiener Filter

2017-06-05
2017-01-1870
The objective of this paper is to develop a robust methodology to study internal combustion (IC) engine block vibrations and to quantify the contribution of combustion pressure loads and inertial loads (mechanical loads) in overall vibration levels. An established technique for noise separation that, until recently, has not been applied to engine noise is Wiener filtering. In this paper, the harmonic part of the overall vibration response of the IC engine block is removed, resulting in a residual broadband response which is uncorrelated to the source signal. This residue of the response signal and the similarly calculated residue of the combustion pressure represent the dynamic portion of their respective raw signals for that specific operating condition (engine speed and load). The dynamic portion of the combustion pressure is assumed to be correlated only to the combustion event.
Technical Paper

Low Frequency Airborne Panel Contribution Analysis and Vehicle Body Sensitivity to Exhaust Nnoise

2017-06-05
2017-01-1865
The tendency for car engines to reduce the cylinder number and increase the specific torque at low rpm has led to significantly higher levels of low frequency pulsation from the exhaust tailpipe. This is a challenge for exhaust system design, and equally for body design and vehicle integration. The low frequency panel noise contributions were identified using pressure transmissibility and operational sound pressure on the exterior. For this the body was divided into patches. For all patches the pressure transmissibility across the body panels into the interior was measured as well as the sound field over the entire surface of the vehicle body. The panel contributions, the pressure distribution and transmissibility distribution information were combined with acoustic modal analysis in the cabin, providing a better understanding of the airborne transfer.
Technical Paper

Fan Noise Prediction for Off-Highway Vehicle

2017-06-05
2017-01-1834
Fan noise can form a significant part of the vehicle noise signature and needs hence to be optimized in view of exterior noise and operator exposure. Putting together unsteady CFD simulation with acoustic FEM modeling, tonal and broadband fan noise can be accurately predicted, accounting for the sound propagation through engine compartment and vehicle frame structure. This paper focuses on method development and validation in view of the practical vehicle design process. In a step by-step approach, the model has been validated against a dedicated test-set-up, so that good accuracy of operational fan noise prediction could be achieved. Main focus was on the acoustic transfer through the engine compartment. The equivalent acoustic transfer through radiators/heat exchangers is modeled based on separate detailed acoustic models. The updating process revealed the sensitivity of various components in the engine compartment.
Magazine

MOBILITY ENGINEERING: June 2017

2017-06-01
Alternative fuels and challenges Automotive powertrain development: virtually-connected hardware co-simulation Functional Safety-progressing towards safer mobility Electric rockets and the future of satellite propulsion Achates powers toward production A potential ICE game-changer, the Achates OP engine is being tooled up for production at one OEM while a new 2.7-L triple for light-truck demonstrations enters the build phase. Engineering with simulation and data Companies are discovering new simulation techniques, especially optimization; the next step is to combine simulation with sensor data and predictive analytics to create even more robust off-highway equipment.
Magazine

SAE Truck & Off-Highway Engineering: April 2017

2017-04-06
Connectivity continues its advance More OEMs and Tier 1 suppliers are focusing on embedded telematic systems, hoping to displace aftermarket hardware. Tailoring fuel injection to control NOx The next big step to help heavy-duty diesel engines meet stricter emissions regulations involves adapting the fuel-injection system to the combustion needs. Active on safety Crash-avoidance technologies are vital "building blocks" to automate commercial vehicles, implement truck platooning and ultimately achieve zero accidents. Engineering with simulation and data Companies are discovering new simulation techniques, especially optimization; the next step is to combine simulation with sensor data and predictive analytics to create even more robust off-highway equipment.
Magazine

MOBILITY ENGINEERING

2016-12-01
Focus on advanced safety systems and human-factor interventions The impact of REACH on the aviation sector Considered the most comprehensive chemical-regulation legislation to date, REACH presents serious ramifications for the aircraft industry. Lightweighting: What's Next? Experts weigh in on the challenges and future enablers in the battle to reduce vehicle mass. The best of COMVEC 2016 Autonomous vehicles and improved fuel efficiency via advanced powertrain solutions are pressing topics detailed in this select group of technical papers from the SAE Commercial Vehicle Engineering Congress. Optimizing waste heat recovery for long-haul trucks Autonomous solutions in agriculture Downsizing a HD diesel engine for off-highway applications Zero-emissions electric aircraft: Theory vs. reality
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