Browse Topic: Fire
ABSTRACT Raytheon is in the final stages of production of three high performance thermal imaging / fire control systems being integrated on existing USMC and US Army armored vehicles. A goal in the design of these systems was to provide integration into the host vehicle that when viewed by the customer and user provided the enhanced capabilities of today’s latest thermal imaging and image processing technology as well as operating in concert with the vehicle as originally designed. This paper will summarize the technical solutions for each of these programs emphasizing the thermal imaging, fire control, image processing and vehicle integration technologies. It will also outline guiding philosophies and lessons learned used to focus the design team in achieving the successful integration. The programs to be reviewed are; USMC 2nd Gen Thermal Imaging System, the USMC LAV-25 Improved Thermal Sight System (ITSS) and the USMC / US Army M1A1 50 Cal Thermal Sight / DayTV System
ABSTRACT Abuse response of lithium-ion batteries has been extensively studied over several decades. Most studies on the onset and propagation of battery fires following mechanical deformation are focused on understanding the onset of thermal events following quasi-static loading. Using an array of cylindrical lithium-ion cells as example, we report results from ultra-high strain-rate deformation mechanical events (> 100 /s) that result in electrochemical short-circuits followed by thermal events. We present a methodology that takes stock of gas compositions as a function of state of charge and compute flammability limits. Finally, we discuss implications for flame lengths and propensity for propagation of thermal events. Citation: J. Kim, A. Mallarapu, S. Santhanagopalan, Y. Ding, “Propagation of Fire in Li-Ion Batteries under Ultra-High Strain-Rate Deformation” In Proceedings of the Ground Vehicle Systems Engineering and Technology Symposium (GVSETS), NDIA, Novi, MI, Aug. 16-18, 2022
ABSTRACT Northrop Grumman has developed a software and hardware solution to provide enhanced 360 degree local situational awareness (LSA) to enable the warfighter with an overmatch capability on today’s modern battlefield. The architecture exploits technological gains in cameras, video processing, and video compression. The approach allows rapid comprehension of local and remote situational views presented with operational relevance for a ground combat platform or tactical wheeled platform crew. The 360 Degree LSA approach provides direct visualization of relative positioning of targets, threats, and lines of fire; and additionally offers common situational understanding / operational picture from the dismounted soldier to higher echelon commands. The approach provides prioritized information through LSA software to provide an enhanced view to the warfighter whereas the squad leader becomes an integral part of the crew with a view of the common operating picture (mounted) and
Letter from the Focus Issue Editors
It is well known that target state estimation and prediction methods can have a substantial influence on the outcome of long range, precision-oriented engagements. Due to this fact, a collection of techniques and algorithms have been developed for the purpose of minimizing the delivery error caused by target motion over the flight time of a munition. These legacy compensation techniques have typically come from direct fire, accuracy-oriented assets such as main battle tanks and attack helicopters. However, with the proliferation of unmanned vehicles in the battle space, the target state estimation and prediction capabilities could be extended into the indirect fire domain. The work conducted within examines the challenge of utilizing a reconnaissance drone partnered with a decoupled weapon platform to track a target, predict its motion, and calculate a lead. The information presented within establishes the framework required to enable this capability, develops the individual solution
Notice of Concern
A global team of researchers and industry collaborators led by RMIT University has invented recyclable ’water batteries’ that won’t catch fire or explode
Where there’s smoke, there will be no fire because a drone is already on the scene. At least that’s the hope of Zhaodan Kong, Professor in the Department of Mechanical and Aerospace Engineering, and his team at the University of California, Davis
Northrop Grumman Corporation is developing AN/APG-85, an advanced Active Electronically Scanned Array (AESA) radar for the F-35 Lightning II. Northrop Grumman currently manufactures the AN/APG-81 active electronically scanned array (AESA) fire control radar, the cornerstone to the F-35 Lightning II’s sensor suite
Cage structures made with nanoparticles could be a step toward making organized nanostructures with mixed materials, and researchers at the University of Michigan have shown how to achieve this through computer simulations
The world community is constantly and rapidly moving toward the search for alternative and ecologically clean energy sources, including for transport, and Russia’s war against Ukraine only intensified and accelerated such processes. This trend in transport is reflected in the spread of battery-powered electric vehicles (BEVs) with zero emission of harmful gases. Electric cars are experiencing a rapid increase in numbers, accompanied by the emergence of lesser-known risks. Among these hazards are the occurrence of fires in electric vehicles, primarily caused by component failures, notably the widely prevalent lithium-ion batteries. Fires of such cars have a different character compared to fires of vehicles powered by an internal combustion engine vehicle (ICEV). In this study, using the fire dynamics simulator developed by the National Institute of Standards and Technology, a BEV fire was simulated on the example of the Tesla Model S. For this, a description of the objects and their
This document provides guidance for in-flight rest facilities provided for use by cabin crew on commercial transport airplane. This document is applicable to dedicated cabin crew rest facilities with rigid walls. The facility includes a bunk or other surface that allows for a flat sleeping position, is located in an area that is temperature-controlled, allows the crew member to control light, and provides isolation from noise and disturbance
This SAE Recommended Practice describes a test method for determination of heavy truck (Class VI, VII, and VIII) tire force and moment properties under cornering conditions. The properties are acquired as functions of normal force and slip angle using a sequence specified in this practice. At each normal force increment, the slip angle is continually ramped or stepped. The data are suitable for use in vehicle dynamics modeling, comparative evaluations for research and development purposes, and manufacturing quality control. This document is intended to be a general guideline for testing on an ideal machine. Users of this SAE Recommended Practice may modify the recommended protocols to satify the needs of specific use-cases, e.g., reducing the recommended number of test loads and/or pressures for benchmarking purposes. However, due care is necessary when modifying the protocols to maintain data integrity
A research team at the University of Central Florida has developed technology that could prevent electric vehicle fires, like those caused by saltwater flooding from Hurricane Ian
Among the limitations of electric vehicles (EVs) is the lack of a long-lasting, high-energy-density battery that reduces the need to fuel up on long-haul trips. The same is true for houses during blackouts and power grid failures — small, efficient batteries able to power a home for more than one night without electricity don’t yet exist. A major issue is that while rechargeable lithium metal anodes play a key role in how well this new wave of lithium batteries functions, during battery operation, they are highly susceptible to the growth of dendrites — microstructures that can lead to dangerous short-circuiting, catching on fire, and even exploding
Innovators at NASA Johnson Space Center have developed a high-powered infrared (IR) laser that can trigger Li-ion battery cells into thermal runaway (TR) without perforating the battery’s wall like previous methods. Inducing TR in a battery cell allows engineers to test and improve the safety performance of overheated batteries that can potentially catch fire or explode. The primary advantage of this method is the heat energy delivered by the laser can be localized to the exact target spot on the battery cell minimizing thermal biasing to adjacent cells
This SAE Recommended Practice provides design, test, and performance guidelines on the comfort, fit, and convenience for active restraint systems for heavy trucks and multipurpose passenger vehicle applications over 10000 pounds gross vehicle weight rating (GVWR). The information pertains to the forward facing seating positions
As a rule of thumb, autonomous vehicle platforms demand for a safety stringent electronic control unit (Ex: Steering Control, Brake control). In such complex systems, monitoring the thermal behavior of the electronic sub-components is very essential. The thermal behavior of individual sub-components in electronic control unit like ICs, MOSFETs, microcontrollers can be modelled by its appropriate thermal characterization. Proper thermal characterization of the sub-components shall assure reduced thermal events. Currently, there are techniques like inter-dependent temperature monitoring between sub-components for detecting and mitigating thermal events on a sub-component within the electronic control unit as a safety mechanism. But these techniques can fail in real time if certain use-cases are not taken into consideration during the design phase of the electronic control unit. This paper focusses on enhancing the thermal characterization of the electronic control unit components
This document includes recommendations of installations of adequate landing and taxiing lighting systems in aircraft of the following categories: a Single engine personal and/or liaison type b Light twin engine c Large multiengine propeller d Large multiengine turbojet e Military high performance fighter and attack f Helicopter which are subject to the following CFR Parts certification: Part 23 – Airworthiness Standards: Normal, Utility, Acrobatic and Commuter Aircrafts Part 25 – Airworthiness Standards: Transport Category Aircrafts Part 27 – Airworthiness Standards: Normal Category Rotorcraft Part 29 – Airworthiness Standards: Transport Category Rotorcraft
Innovators at NASA Johnson Space Center have developed a high-powered infrared (IR) laser that can trigger Li-ion battery cells into thermal runaway (TR) without perforating the battery’s wall like previous methods. Inducing TR in a battery cell allows engineers to test and improve the safety performance of overheated batteries that can potentially catch fire or explode. The primary advantage of this method is the heat energy delivered by the laser can be localized to the exact target spot on the battery cell minimizing thermal biasing to adjacent cells
Electric vehicle batteries typically require a tradeoff between safety and energy density. If the battery has high energy and power density — required for uphill driving or merging on the freeway — then there is a chance the battery can catch fire or explode in the wrong conditions. But materials that have low energy/power density, and therefore high safety, tend to have poor performance. There is no material that satisfies both
Currently, two materials are used as anodes in most commercially available lithium-ion batteries that power items like cellphones, laptops, and electric vehicles. The most common, a graphite anode, is extremely energy dense — a lithium-ion battery with a graphite anode can power a car for hundreds of miles without needing to be recharged; however, recharging a graphite anode too quickly can result in fire and explosions due to a process called lithium metal plating. A safer alternative, the lithium titanate anode, can be recharged rapidly but results in a significant decrease in energy density, which means the battery needs to be recharged more frequently
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