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Journal Article

Heat Transfer Study of a Battery Module for Micro-mobility

2022-08-02
Abstract This study was conducted to establish a reliable thermal analysis methodology for the battery module designed for micro-mobility. Analyses and experiments were performed first with a single cell and subsequently with a battery module consisting of 80 cells. The heat generation calculated from a single-cell experiment and realistic thermophysical properties were used in the module analysis to predict the temperature rise and distribution at various discharge rates. A prototype battery module was then built and ten thermocouples were used to measure temperatures at various locations in the module. Good correlation was achieved between the analytical results and experimental data. In particular, the model is accurate in predicting temperature distribution and the locations of peak temperatures. As a next step, the analytical methods developed in this study will be used to optimize the battery pack design and enhance its thermal performance.
Journal Article

Comparison of Performance and Emission Characteristics of a Gasoline Engine with Laser and Spark Ignitions in Partially Stratified Mode—A Computational Fluid Dynamics Analysis

2022-08-02
Abstract Generally, homogeneous mixture combustion is preferred at high loads in conventional spark-ignition engines. But homogeneous mixture combustion can lead to high hydrocarbon (HC) emissions at low loads. Thereby, stratified mixture combustion with an overall lean mixture is preferred at low loads, which can significantly reduce HC emissions, but NOx and soot emissions will increase. Nowadays, gasoline direct injection (GDI) engines are becoming popular because of better thermal efficiency and low emissions at all loads. These engines work with a stratified mixture at low-load conditions and a homogeneous mixture at high-load conditions. But the problem with these engines is high nitrogen oxides (NOx) and soot emissions at low-load conditions. Therefore, today, the concept of partial stratification is tried in these engines, which is a combination of the combustion of stratified and homogeneous mixtures, using both GDI and port fuel injection (PFI) techniques.
Journal Article

A Novel Cloud-Based Additive Manufacturing Technique for Semiconductor Chip Casings

2022-08-02
Abstract The demand for contactless, rapid manufacturing has increased over the years, especially during the COVID-19 pandemic. Additive manufacturing (AM), a type of rapid manufacturing, is a computer-based system that precisely manufactures products. It proves to be a faster, cheaper, and more efficient production system when integrated with cloud-based manufacturing (CBM). Similarly, the need for semiconductors has grown exponentially over the last five years. Several companies could not keep up with the increasing demand for many reasons. One of the main reasons is the lack of a workforce due to the COVID-19 protocols. This article proposes a novel technique to manufacture semiconductor chips in a fast-paced manner. An algorithm is integrated with cloud, machine vision, sensors, and email access to monitor with live feedback and correct the manufacturing in case of an anomaly.
Journal Article

Multi-objective Optimization under Uncertainty of a Continuously Variable Transmission for a 1.5 MW Wind Turbine

2022-08-02
Abstract This article presents an original methodology for the multi-objective optimization of Continuously Variable Transmission (CVT) for a wind turbine (WT). The objective functions of this optimization problem are to minimize the weight and maximize efficiency. This methodology also considers the variations of parameters caused by different factors (manufacturing tolerance, uncertainties in the operating conditions). Using a probabilistic model, the proposed algorithm combines a propagation of uncertainties and an optimization of the function objectives. The optimization is performed using the Non-dominated Sorting Genetic Algorithm (NSGA-II) with the advantage of exploring the global design space and finding the best compromise between the objectives. In order to verify the solution obtained by this approach, results were compared to the ones obtained by a previous study.
Journal Article

Design and Control Co-optimization of a Mixed Hybrid Electric Powertrain Architecture

2022-08-02
Abstract Electrification of vehicles can improve energy efficiency and reduce emissions in vehicle operations. Studies have focused on designing powertrains of several topologies, including serial, parallel, and power-split hybrid powertrains. In this study, a design and control co-optimization is demonstrated for a novel mixed-powertrain architecture. The component sizes of the mixed powertrain are optimized to minimize the fuel and component costs. Nested optimization is applied with a surrogate integrated operation and control model that evaluates powertrain performance in the inner loop. The surrogate model is trained to capture the powertrain performance under a near-optimal power management approach, namely, the equivalent consumption minimization strategy (ECMS). Using sequential quadratic programming, optimal results are obtained and verified using a high-fidelity powertrain model which is equipped with ECMS control.
Standard

Lubricating Oil, Aircraft Piston Engine (Ashless Dispersant)

2022-08-02
WIP
J1899

This SAE Standard establishes the requiremetns for lubricating oils containing ashless dispersant additives to be used in four-stroke cycle, reciprocating piston aircraft engines. This document covers the same lubricating oil requirements as the former military specification MIL-L-22851. Users should consult their airframe or engine manufacturers manuals for the latest listing of acceptable lubricants.

Standard

Pilot Training Recommendations for Unmanned Aircraft Systems (UAS) Civil Operations

2022-08-02
WIP
ARP5707A
This document provides an approach to the development of training topics for pilots of Unmanned Aircraft Systems (UAS) for use by operators, manufacturers, and regulators. The identification of training topics is based initially on Practical Test Standard (PTS) topics for manned aircraft pilots. The topics identified could be used for the construction of a PTS for UAS commercial pilot operations and a PTS for a UAS pilot instrument rating. The UAS commercial pilot rating would contain restrictions on the types of operations that could be flown that would be dependent on the type of UAS used. The UAS type would also influence the specific training topics that would be covered. This document is not intended to outline the requirements for other crewmembers, such as observers, payload operators, or ground personnel, nor does it distinguish between different levels of pilot authority or discuss the roles for pilot-in-command, supplemental pilot, or observer.
Magazine

Aerospace & Defense Technology: August 2022

2022-08-01
The Digital Cockpit of the Future How Human Machine Interface Technology Will Impact Avionics Displays The Science of Joining Dissimilar Metals in Aerospace Manufacturing Designing A/D Converters for the James Webb Space Telescope Vibration Testing NASA's X-57 Maxwell Electric Aircraft Hybrid Circulators for mmWave Systems Transforming Battlespace Communications Pulsed Exposure Toxicity Testing: Method Development and Initial Evaluation for Stormwater Compliance Preliminary research into modifying whole effluent toxicity (WET) testing protocols designed for continuous flow discharges as applied to episodic and/or ephemeral discharges such as those associated with storm water runoff. Upgrade Transonic Compressor Test Rig Data Acquisition System New software programming using commercial off-the-shelf software for acquiring data, processing data, displaying results, and generating reports is implemented to improve the performance of a legacy system.
Standard

Architecture Examples for Electrified Propulsion Aircraft

2022-08-01
CURRENT
AIR8678
The application of electric power for aircraft propulsion can take a variety of forms, ranging from partial electric to full electric. The introduction of electric engines to drive propulsors, along with the variety of available methods to generate electricity and store energy offers great degree of new design freedom for next-generation aircraft and aircraft architectures. This newfound design freedom exposes a need within the aviation industry to establish a common design language for electrified propulsion. While this need for a common design language is recognized, the intent of this document is to encourage innovation, providing reference architectures as a launching point for future work in this area. This document will describe potential electrified propulsion architectures and provide examples.
Standard

Nomenclature and Definitions for Electrified Propulsion Aircraft

2022-08-01
CURRENT
ARP8676
Create and publish a list of terms relevant to electrified propulsion aircraft with summary text descriptions. The terms and descriptions will not provide full explanations, diagrams, and other detailed technical descriptions. These deeper descriptions will be addressed in other documents. This document defines the relevant terms and abbreviations related to the design, development, and use of electrified propulsion in aircraft. This definition is provided to enable a consistent use of technical language throughout the standards developed by the E-40 committee.
Book

Is an Electric Car Right for You?

2022-08-01
The automotive industry is manufacturing more electric vehicles than ever before. It’s not uncommon to see an electric vehicle pull up next to you at a stop light or to pass a charging station beside the road. But what exactly is an electric vehicle? Will it really save you money? Are they hard to maintain? This quick reference guide takes the mystery out of the electric vehicles. We will walk you through the process of deciding if an electric vehicle is right for you. You’ll discover the benefits of electric vehicles, what to know before you buy, and what to do after you bring it home. In addition, a special section is dedicated to addressing common misconceptions such as whether or not EVs have enough range to be a viable option for your transportation needs. Isn’t it time you discover if an electric vehicle is the right choice for you?
Magazine

Automotive Engineering: July/August 2022

2022-08-01
R1T Exposed! A comprehensive teardown of Rivian's pioneering electric pickup reveals praiseworthy build quality, innovative thinking…and some lapses in manufacturability. EVs drive NVH materials innovation Skateboard platforms, high-frequency motor noise push lower dB thresholds and new countermeasure solutions. Optimizing design for additive manufacturing Avoiding the pitfalls of 3D printing requires knowing the process limitations - and how to work around them. An expert at a leading AM specialist shares insights on getting it right. Real-time processors help drive the zonal E/E revolution With its new generation of software-compatible processors, NXP aims to accelerate systems consolidation and performance.
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