Browse Topic: Weather and climate

Items (3,984)
ABSTRACT The department of defense currently uses a number of models of vehicle start batteries with the “6T” form factor. These batteries are typically found in almost every vehicle in the DOD fleet and other systems that require 28VDC power. The use of power and energy on the battlefield is significantly changing and the Warfighter now requires a “start” battery that is used for more than just starting, lighting and ignition (SLI) for the vehicle. Lithium ion battery technologies are showing great promise in addressing these challenges by providing higher power capability for extended silent watch, battery monitoring and extended cycle life. One concern, however, is their ability to operate at low temperatures. One of the most challenging aspects of battery use in military applications is their operation at extreme high and low temperatures. These wide temperature swings can potentially have a dramatic effect on cycle life and performance. One significant concern, especially for
Marcel, MikeKnakal, TonyHelm, JeffFagan, BaileyAlexander, Les
ABSTRACT TIAX is developing laminated prismatic lithium-ion (Li-ion) cell technology capable of rapid charging at low temperature (to -50 °C) to replace current lead-acid vehicle batteries. The novel cells are based on TIAX’s high energy, high power CAM-7 cathode material, high rate capability lithium titanate (LTO) anode material, and novel electrolyte formulation, and target cell-level energy content greater than 90 Wh/kg and 250 Wh/l. CAM-7 cathode material promises significant boost in power and run time of Li-Ion batteries for a wide range of DoD applications, and is now being commercialized by a separate company, CAMX Power, which is scaling up production in a 50 metric ton per year plant installed in Massachusetts
Ofer, DavidDalton-Castor, SharonNation, LeahPullen, AdrianRempel, JaneBarnett, BrianSriramulu, Suresh
This paper investigates the condensation within a two-wheeler instrument cluster in different weather conditions. Instrument cluster have high heating components within its assembly particularly over Printed Circuit Board (PCB) which leads to formation of condensation. Air breathers are important component that can be utilized to reduce the condensation in the cluster. Location and orientation of air breather and air vents plays the vital role in the air flow through the instrument cluster. In this study, number of breathers, their location and orientation are optimized to reduce the condensation or film thickness on the crystal (transparent body) of cluster. Transient Computational Fluid Dynamics (CFD) based Eulerian Wall Film approach is utilized to investigate the physics administering the condensation phenomenon in the instrument cluster. Experimental tests are conducted to investigate condensation phenomenon actually occurring in the model. Similar results are found by employing
Jamge, NageshShah, VirenKushari, SubrataMiraje, JitendraD, Suresh
Autonomous vehicle technologies have become increasingly popular over the last few years. One of their most important application is autonomous shuttle buses that could radically change public transport systems. In order to enhance the availability of shuttle service, this article outlines a series of interconnected challenges and innovative solutions to optimize the operation of autonomous shuttles based on the experience within the Shuttle Modellregion Oberfranken (SMO) project. The shuttle shall be able to work in every weather condition, including the robustness of the perception algorithm. Besides, the shuttle shall react to environmental changes, interact with other traffic participants, and ensure comfortable travel for passengers and awareness of VRUs. These challenging situations shall be solved alone or with a teleoperator’s help. Our analysis considers the basic sense–plan–act architecture for autonomous driving. Critical components like object detection, pedestrian tracking
Dehghani, AliSalaar, HamzaSrinivasan, Shanmuga PriyaZhou, LixianArbeiter, GeorgLindner, AlisaPatino-Studencki, Lucila
One of the major goals of the automotive industry is to improve vehicular fuel efficiency and performance with much lesser percentages of harmful tailpipe emissions. One of the major technologies includes fuel cell electric vehicles (FCEV). Fuel cell electric vehicle can positively affect the transportation industry with regards to increase in the greenhouse gas emission, air pollution. A proton exchange membrane (PEM) fuel cell that is widely used in commercial vehicles takes hydrogen and oxygen to generate the electricity. Hydrogen stored either in liquid or compressed gas, is supplied from anode end and oxygen from atmosphere is supplied from cathode end. The atmospheric air, which enters fuel cell, also contains pollutants such as nitrogen oxides (NOx), Sulphur oxides (SOx), carbon monoxides and dioxides (CO, CO2), methane, ammonia etc. Operation of fuel cell in a geographic region, where the concentration of pollutants mentioned is significant leads to adsorption on the catalysts
Bhat, AdithyaShah, SaurabhChoubey, AyushBarik, MadhusmitaMallappanavar, BabuPrasad P, Shilpa
India features diverse climatic zones, spanning from tropical in south to alpine in north. Since most of the regions are hot, vehicle cabin cooling analysis dominates over heating analysis, creating a notable technology gap that exists in cabin heating. Nonetheless, in colder regions of India and Europe, maintaining optimal cabin heating is crucial for human comfort. Furthermore, in climates prone to mist and frost formation, ensuring the accuracy and effectiveness of cabin heating mechanisms becomes crucial, as it directly correlates with safety considerations that comes prior to mere comfort requirements. To reduce the technology gap and physical testing in cold climatic conditions this work is proposed, which will enable us to predict cabin heating performance of vehicle on highway running as well as in stationary condition for Electric Vehicles (EV) and Internal Combustion Engine Vehicles (ICEV) in 1D Computer Aided Engineering (CAE) software. A detailed Transient Cabin Heating
Soni, RahulShah, GeetKulkarni, ShridharM, ChandruVangala, Sai KrishnaJaybhay, SambhajiNayakawadi, Uttam
The purpose of air conditioning (AC) duct packing is multifaceted, serving to prevent condensation, eliminate rattle noise, and provide thermal insulation. A critical aspect of duct packing is its adhesive quality, which is essential for maintaining the longevity and effectiveness of the packing's functions. Indeed, the challenge of achieving adequate adhesivity on AC ducting parts is significant due to the harsh operating conditions to which these components are subjected. The high temperatures and presence of condensation within the AC system can severely compromise the adhesive's ability to maintain a strong bond. Moreover, the materials used for these parts, such as HDPE, often have low surface energy, which further hinders the formation of a durable adhesive bond. The failure of the adhesive under these conditions can lead to delamination of the duct packing, which can result in customer inconvenience due to rattling noises, potential electrical failures if condensed water
M, Amala RajeshSonkar, SurabhiKumar, Mukesh
The European Union plans to reach net-zero greenhouse gas (GHG) emissions in 2050. In 2020, the transport sector significantly contributed to global energy-related GHG emissions, with heavy-duty vehicles (HDVs) responsible for a substantial portion of road transport emissions in the EU and a notable percentage of the EU’s total GHG emissions. Zero-emission vehicles (ZEVs), including fuel cell (FC) vehicles, are crucial for decarbonizing the transport sector to achieve climate neutrality. This paper aims at quantifying the environmental impacts of a 200kW proton exchange membrane FC system for long-haul HDVs with a 40-ton mass and 750 km driving range. The life cycle assessment (LCA) methodology was applied, and a life cycle model of the FC system was developed with a cradle-to-grave boundary. To ensure reproducibility and scalability, results are reported on a kW basis. A sensitivity analysis was performed on key parameters, including hydrogen production route, FC system production
Gentilucci, GaiaAccardo, AntonellaSpessa, Ezio
Since signing the legally binding Paris agreement, fighting climate change has been an increasingly important task worldwide. One of the key energy sectors to emit greenhouse gases is transportation. Therefore, long term strategies all over the world have been set up to reduce on-road combustion emissions. One of the emerging alternative technologies to decarbonize the transportation sector is Mobile Carbon Capture (MCC). MCC refers to the on-board separation of CO2 from vehicle exhaust. To accurately assess this technology, a techno-economic analysis is essential to compare MCC abatement cost to alternative decarbonization technologies such as electric trucks. Adding to the system capital and operational costs, our study includes mass penalty costs, CO2 offloading and transport costs for different transport scenarios. To better relate to a single consumer (driver), the cost can be converted from euro per-tCO2 to euro per-trip or euro per-mile. A sensitivity analysis is then conducted
SAAFI, Mohamed AliHamad, Esam
Fighting climate change has become a major task worldwide. Alongside the United States and China, Europe is considered as one of the biggest greenhouse gases (GHG) emitters. Therefore, the European Union (EU) has set long term strategies to reduce emissions. One of the key energy sectors to emit greenhouse gases is transportation. In this context, EU has turned its eye toward cutting emissions from the transport sector and has recently put its stamp of approval on a reworked law banning all new sales of internal combustion engine (ICE) vehicles from 2035. Despite representing only 2% of the vehicles on the road, trucks account for more than a quarter of road transport emissions in the EU and have been increasing every year since 1990. In order to investigate the impact of transportation projected policies on the heavy-duty sector, we develop the Mobility and Energy Transportation Analysis (META) Model, a python-based model to project market penetration of conventional and alternative
SAAFI, Mohamed Ali
Moisture adsorption and compression deformation behaviors of Semimet and Non-Asbestos Organic brake pads were studied and compared for the pads cured at 120, 180 and 240 0C. The 2 types of pads were very similar in moisture adsorption behavior despite significant differences in composition. After being subjected to humidity and repeated compression to 160 bars, they all deform via the poroviscoelastoplastic mechanism, become harder to compress, and do not fully recover the original thickness after the pressure is released for 24 hours. In the case of the Semimet pads, the highest deformation occurs with the 240 °C-cure pads. In the case of the NAO pads, the highest deformation occurs with the 120 0C-cure pads. In addition, the effect of pad cure temperatures and moisture adsorption on low-speed friction was investigated. As pad properties change all the time in storage and in service because of continuously changing humidity, brake temperature and pressure, one must question any
Rhee, Seong KwanRathee, AmanSingh, ShivrajSharma, Devendra
When the brakes are released and the vehicle starts, the brakes and suspensions vibrate and the car body resonates at 10 to 300 Hz, which is called brake creep groan. This low-frequency noise is more likely to occur in high-humidity environments. As vehicles become quieter with the introduction of EVs, improving this low-frequency noise has become an important issue. It is known that the excitation force is the stick-slip between the brake rotor and pads, but there are few studies that directly analyze stick-slip occurring in a vehicle. Acoustic emission (AE) is a phenomenon in which strain energy stored inside a material is released as elastic stress waves, and AE sensing can be used to elucidate the friction phenomena. In this study, the AE sensing is used to analyze changes in the stick-slip occurrence interval and generated energy when creep groan occurs. As a result, it was confirmed that the AE signal increased with high humidity. Furthermore, the friction phenomena during creep
Toyoda, HajimeYazawa, YusukeArai, ShinichiOno, ManabuHara, YasuhiroHase, Alan
The ongoing transition from fossil fuels to renewable energy sources has never been more important as climate change and sustainability awareness continue to rise
Sustainability remains a dominant trend in packaging and processing, continuing to attract the attention of the life sciences industry and inspire its new initiatives. Although pharmaceutical and medical device manufacturers must prioritize patient safety and product protection, concerns about climate change, greenhouse gas (GHG) emissions, plastic waste, and pressure to move toward a circular economy are prompting a greater focus on improving the sustainability of their products and packaging
Researchers at the Department of Energy’s Oak Ridge National Laboratory are developing battery technologies to fight climate change in two ways, by expanding the use of renewable energy and capturing airborne carbon dioxide
Society is moving towards climate neutrality where hydrogen fuelled combustion engines (H2 ICE) could be considered a main technology. These engines run on hydrogen (H2) so carbon-based emission are only present at a very low level from the lube oil. The most important pollutants NO and NO2 are caused by the exhaust aftertreatment system as well as CO2 coming from the ambient air. For standard measurement technologies these low levels of CO2 are hard to detect due to the high-water content. Normal levels of CO2 are between 400-500 ppm which is very close or even below the detection limit of commonly used non-dispersive-infrared-detectors (NDIR). As well the high-water content is very challenging for NOx measuring devices, like chemiluminescence detectors (CLD), where it results in higher noise and therefore a worse detection limit. Even for Fourier-transformed-infrared-spectroscopy-analysers (FT-IR) it is challenging to deal with water content over 15% without increased noise. The goal
Jakubec, PhilippRoiser, Sebastian
A new report from Clarivate Plc, London, UK, offers a predictive analysis of high-growth medical technology markets poised to generate over $1 billion in value or achieve double-digit growth within the next five years. The report, “Medical Technologies to Watch in 2024” underscores critical areas of significant investment. Medtech analysts pinpoint five technologies driving substantial clinical and commercial value in devices and diagnostics this year. These innovations hold immense promise for patients, potentially complementing or even supplanting traditional medications and biochemical solutions. Analysts are optimistic that 2024 will bring a more favorable economic climate for medtech competitors, noting that the macro trends remain positive
The problem of transport-related greenhouse gas (GHG) emissions is common knowledge. In recent years, the electrification of cars is being prompted by many as the best solution to this issue. However, due to their rather big battery packs, the embedded ecological footprint of electric cars has been shown to be still quite high. Therefore, depending on the size of the vehicle, tens -if not hundreds- of thousands of kilometres are needed to offset this burden. Human-powered vehicles (HPVs), thanks to their smaller size, are inherently much cleaner means of transportation, yet their limited speed impedes widespread adoption for mid-range and long-range trips, favouring cars, especially in rural areas. This paper addresses the challenge of HPVs speed, limited by their low input power and non-optimal distribution of the resistive forces. The article analyses dissipation sources from rolling resistance, aerodynamics, inertia, and more for various vehicles, emphasizing the fundamental role of
Di Gesù, AlessandroGastaldi, ChiaraDelprete, Cristiana
A GE Aviation Systems report for a project, conducted under the CLEEN Program to develop the Flight Management System Weather Input Optimizer (FWIO), documents that the National Oceanic and Atmospheric Administration (NOAA) provided weather forecast data has a bias of 15 knots and a standard deviation of 13.3 knots for the 40 flights considered for the research. It also had a 0.47 bias in the temperature with a standard deviation of 0.27. The temperature errors are not as significant as the wind. There is a potential opportunity to reduce the operational cost by improving the weather forecast. The flight management system (FMS) currently uses the weather forecast, available before takeoff, to identify an optimized flight path with minimum operational costs depending on the selected speed mode. Such a flight plan could be optimum for a shorter flight because these flight path planning algorithms are very less susceptible to the accuracy of the weather forecast. However, the flight plan
Kushwaha, DineshKottackal, Sebin K
The transportation sector has an enormous demand for resources and energy, is a major contributor of emissions (i.e., greenhouse gases in particular), and is defined largely by the kind of energy it uses—be it electric cars, biofuel trucks, or hydrogen aircraft. Given the size of this sector, it has a crucial role in combating climate change and securing sustainability in its three forms: environmental, societal, and economic. In this context, there are many questions concerning energy options on the path toward a more sustainable transportation sector. Is hydrogen the fuel of the future? Is there enough electricity to power a fully electric transportation sector? What happens when millions of electric vehicle batteries need to be decommissioned? Which regulatory measures are effective and appropriate for moving the sector in the right direction? What is the “right” direction? This chapter does not aim to answer all those questions. It does, however, highlight and discuss the most
Beiker, SvenMuelaner, Jody E.
On a cold, sunny day, you’re driving on a rural road, surrounded by snow-covered fields. In an instant, your eyes process the scene, picking out individual objects to focus on — a stop sign, a barn — while the rest of the scene blurs in the periphery. Your brain stores the focused and blurred images as a memory that can be pictured in your mind later, while sitting at your desk
Robots and autonomous vehicles can use 3D point clouds from LIDAR sensors and camera images to perform 3D object detection. However, current techniques that combine both types of data struggle to accurately detect small objects. Now, researchers from Japan have developed DPPFA–Net, an innovative network that overcomes challenges related to occlusion and noise introduced by adverse weather
NASA’s Johnson Space Center is offering an innovative freeze-resistant hydration system for licensing. The technology substantially improves on existing hydration systems because it prevents water from freezing in the tubing, container, and mouthpiece, even in the harshest conditions on Earth
With globalization, vehicles are sold across the world throughout different markets and their automotive brake systems must function across a range of environmental conditions. Currently, there is no current standardized test that analyzes brake pads’ robustness against severe cold and humid environmental conditions. The purpose of this proposed test method is to validate brake system performance under severe cold conditions, comparing the results with ambient conditions to evaluate varying lining materials’ functional robustness. The goal of this paper is to aid in setting a standardized process and procedure for the testing of automotive brakes’ environmental robustness. Seven candidate friction materials were selected for analysis. The friction materials are kept confidential. Design of experiment (DOE) techniques were used to create a full-factorial test plan that covered all combinations of parameters. The test script involves brake applications at 5, 10, 15, and 20 bar, at both
Passador, Stephen Daniel AustinBoudreau, Douglas BarretCapacchione, Christopher James
The potential blinding of Advanced Driver Assistance Systems (ADAS) sensors due to contamination poses a notable threat to autonomous vehicles. These sensors' performance can be compromised by diverse sources such as dust, water, or snow. However, our investigation concentrates primarily on snow-related contamination, a frequent occurrence during winter. The accumulation of snow and ice significantly hampers the operational efficacy of autonomous vehicles. Over the years, a series of field tests and wind tunnel experiments have been conducted to analyze the mechanisms of snow interaction and soiling patterns on vehicles and bluff bodies. Notably distinctive patterns of soiling have been identified across multiple areas of these structures. The central challenge revolves around constructing an accurate model to predict snow buildup on vehicles. The precision in capturing the airflow dynamics, which substantially influences how the snow interacts with the specific body, is crucial for
Makam, Sri Lalith MadhavShah, SrishtyVarghese, RixsonWalia, Rajat
Ambient temperature is a very sensitive use condition for electric vehicles (EVs), so it is imperative to ensure the maintenance of suitable temperature. This is particularly important in regions characterized by prolonged exposure to unfavorable temperature conditions. In such cases, it becomes necessary to implement insulation measures within parking facilities and allocate energy resources to sustain a desired temperature level. Solar energy is a renewable and environmentally friendly source of energy that is widely available. However, the effectiveness of utilizing solar energy is influenced by various factors, such as the time of day and weather conditions. The use of phase change material (PCM) in a latent heat energy storage (LHES) system has gained significant attention in this field. In contrast to single-phase energy storage materials, PCM offer a more effective heat storage capacity. Leveraging their attributes, PCM can harness their latent heat to address the issue of
Zhang, TianmingZheng, HaoyunSun, MingzheZhang, JiayiRen, Jindong
With the increasing demand for Battery Electric Vehicles (BEVs) capable of extended mileage, optimizing their efficiency has become paramount for manufacturers. However, the challenge lies in balancing the need for climate control within the cabin and precise thermal regulation of the battery, which can significantly reduce a vehicle's driving range, often leading to energy consumption exceeding 50% under severe weather conditions. To address these critical concerns, this study embarks on a comprehensive exploration of the impact of weather conditions on energy consumption and range for the 2019 Nissan Leaf Plus. The primary objective of this research is to enhance the understanding of thermal management for BEVs by introducing a sophisticated thermal management system model, along with detailed thermal models for both the battery and the cabin. These models are seamlessly integrated into a 2019 Nissan Leaf Plus BEV model developed in Autonomie, allowing for a holistic assessment of
Al Haddad, RabihMansour, CharbelKim, NamdooSeo, JiguNemer, Maroun
The discussed invention is centered on the evaporative cooling of a vehicle cabin, introducing a novel concept of humidity control. Unlike conventional Air Conditioning (AC) systems that operate on the Vapor Compression Refrigeration Cycle (VCRC), which tend to be costly and contribute to higher fuel consumption due to the engine-driven compressor in automobiles, there is currently no other Original Equipment Manufacturer (OEM) fitted cabin cooling option available to address this issue. This paper introduces the idea of a humidity-controlled evaporative cooler. The objective of humidity control is achieved through a controller unit that receives feedback from a humidity sensor, subsequently regulating the operation of the water pump. The ambient air is passed through a humidified honeycomb pad, cooling through the principle of evaporation. To prevent any leftover water droplets from entering the cabin, a polyester nonwoven filter has been integrated into the system. This invention not
Dube, DevashishUpkare, Piyush Pradip
In alignment with the U.S. Army's Climate Strategy and the broader trend in automotive technology, there is a strategic shift towards electrification and hybridization of the vehicle fleet. While a major goal of this effort is to mitigate the carbon footprint of the U.S. Army's vehicle operations, this transition also presents an opportunity to harness advancements in automotive electrification. Among the key vehicles in focus are tactical wheeled vehicles, which provide military forces with versatile and rugged transportation solutions for various combat scenarios, ensuring mobility, protection, and adaptability on the battlefield. This study investigates the potential of electrified tactical wheeled vehicles by conducting a survey involving a diverse group of vehicle operators across various ranks within the U.S. Army. The aim is to identify novel applications achievable through electrification or hybridization, encompassing functions such as establishing command posts, prolonged
Konopa, BridgetMiller, MarkRevnew, LukeMuraco, JohnMayfield, LoganRutledge, MaxwellCrocker, MatthewMittal, Vikram
Vehicle efficiency and range, along with the DC charging speed, are deemed as the most important criteria for an electric vehicle currently. The electric vehicle energy consumption is impacted by the change in temperature along with the driving style and average speed of a customer, all other factors being constant. Hence understanding the patterns and impact of different aspects of an EV range & charging speed is crucial in delivering an electric vehicle with robust efficiency across all weather conditions. In this paper we have analysed vehicle parameters of global Jaguar I-PACE customer data. We present and analyse the collated big data of around 50,000+ unique vehicles with a data aggregate of well over 482 million km. In moderate ambient conditions the analysis indicated a good correlation with 50th to 75th percentile drivers’ energy consumption to the EPA label figure. The EPA hot and cold ambient tests also compare well but the correlation is sensitive to long and short trip
Dutta, NilabzaEvans, Davidsapte, Atharva
Energy management of battery electric vehicle (BEV) is a very important and complex multi-system optimisation problem. The thermal energy management of a BEV plays a crucial role in consistent efficiency and performance of vehicle in all weather conditions. But in order to manage the thermal management, it requires a significant number of temperature sensors throughout the car including high voltage batteries, thus increasing the cost, complexity and weight of the car. Virtual sensors can replace physical sensors with a data-driven, physical relation-driven or machine learning-based prediction approach. This paper presents a framework for the development of a neural network virtual sensor using a thermal system hardware-in-the-loop test rig as the target system. The various neural network topologies, including RNN, LSTM, GRU, and CNN, are evaluated to determine the most effective approach. The solution proposed intends to use a combination of the states determined in other sensors and
Wray, AlexPipes, HarryDutta, NilabzaEbrahimi, Kambiz
Accurate and reliable localization in GNSS-denied environments is critical for autonomous driving. Nevertheless, LiDAR-based and camera-based methods are easily affected by adverse weather conditions such as rain, snow, and fog. The 4D Radar with all-weather performance and high resolution has attracted more interest. Currently, there are few localization algorithms based on 4D Radar, so there is an urgent need to develop reliable and accurate positioning solutions. This paper introduces RIO-Vehicle, a novel tightly coupled 4D Radar/IMU/vehicle dynamics within the factor graph framework. RIO-Vehicle aims to achieve reliable and accurate vehicle state estimation, encompassing position, velocity, and attitude. To enhance the accuracy of relative constraints, we introduce a new integrated IMU/Dynamics pre-integration model that combines a 2D vehicle dynamics model with a 3D kinematics model. Then, we employ a dynamic object removal process to filter out dynamic points from a single 4D
Zhu, JiaqiZhuo, GuirongXiong, Luzihang, heLeng, Bo
Focused on the permanent magnet synchronous motor (PMSM) used in electric, this paper proposes an online insulation testing method based on voltage injection under high-temperature and high-humidity conditions. The effect of constant humidity and temperature on the insulation performance has been also studied. Firstly, the high-voltage insulation structure and principle of PMSM are analyzed, while an electrical insulation testing method considered constant humidity and temperature is proposed. Finally, a temperature and humidity experimental cycling test is carried out on a certain prototype PMSM, taking heat conduction and radiation models, water vapor, and partial discharge into account. The results show that the electrical insulation performance of the motor under constant humidity and temperature operation environment exhibits a decreasing trend. This study can provide theoretical and practical references for the reliable durability design of PMSM
Zhang, WeiQiu, ZizhenKong, ZhiguoHuang, XinWang, Fang
Evaluating real-world hazards associated with perception subsystems is critical in enhancing the performance of autonomous vehicles. The reliability of autonomous vehicles perception subsystems are paramount for safe and efficient operation. While current studies employ different metrics to evaluate perception subsystem failures in autonomous vehicles, there still exists a gap in the development and emphasis on engineering requirements. To address this gap, this study proposes the establishment of engineering requirements that specifically target real-world hazards and resilience factors important to AV operation, using High-Definition Maps, Global Navigation Satellite System, and weather sensors. The findings include the need for engineering requirements to establish clear criteria for a high-definition maps functionality in the presence of erroneous perception subsystem inputs which enhances the overall safety and reliability of the autonomous vehicles. In conjunction, global
Masterson, AlexandraPatil, PriteshBrown, NicolasAsher, ZacharyFanas Rojas, JohanSiems-Anderson, AmandaWalker, CurtisRabinowitz, Aaron
The China Automotive Technology and Research Center (CATARC) has completed two new wind tunnels at its test centre in Tianjin, China: an aerodynamic/aeroacoustic wind tunnel (AAWT), and a climatic wind tunnel (CWT). The AAWT incorporates design features to provide both a very low fan power requirement and a very low background noise putting it amongst the quietest in the automotive world. These features are also combined with high flow quality, a full boundary layer control system with a 5-belt rolling road, an automated traversing system, and a complete acoustic measurement system including a 3-sided microphone array. The CWT, located in the same building as the AAWT, has a flexible nozzle to deliver 250 km/h with an 8.25 m2 nozzle, and 130 km/h with a 13.2 m2 nozzle. The temperature range of the CWT is -40 °C to +60 °C with a controlled humidity range of 5% to 95%. Additional integrated systems include a variable angle solar simulator array, and a rain and snow spray system. This
Waudby-Smith, PeterBender, TrevorSooriyakumaran, ChristopherZhang, YilunWang, HaiyangZhao, FengFan, GuangjunSun, JinhongLiu, Xuelong
The author has developed UV based photocatalytic air purification system (Mathur, 2021, 2122, 2023) that can eliminate all pathogens from the cabin air including COVID-19. In this study, the focus is to determine the risk of infection due to pathogens/germs in the cabin of an automobile. Author has determined the risk of infection by using Wells-Riley model and conducted CFD analysis to determine propagation of virus in cabin as a function of: 1 Cabin Volume & Number of Occupants (Wells-Riley Model in OSA mode): (i) Cabin volume from: Small Sedan, Large Sedan and a SUV; with 4 occupants (males & females); Number of infector 1; Air flowrate (m3/min); (ii) A 15-seater minibus – with 10 occupants (males); Number of infectors 1 & 2; Air flowrate (m3/min) 2 CFD to simulate 4 occupants and 1 infector in an automotive cabin – Current investigation is for talking, coughing and sneezing with blower off in Recirc mode wit (i) Infector in the front seat; (ii) Infector in the rear seat. Based on
Mathur, Gursaran
Electric vehicles (EV) present distinctive challenges compared to ICE (Internal Combustion Engine) powered counterparts. Cabin heating and air-conditioning stand out among them, especially cabin heating in cold weather, owing to its outsized effect on drivable range of the vehicle. Efficient management of the cabin thermal system has the potential to improve vehicle range without compromising passenger comfort. A method to improve cabin thermal system regulation by effectively leveraging the solar load on the vehicle is proposed in this work. The methodology utilizes connectivity and mapping data to predict the solar load over a future time horizon. Typically, the solar load is treated as an unmeasured external disturbance which is compensated with control. It can however be treated as an estimated quantity with potential to enable predictive control. The solar load prediction, coupled with a passenger thermal comfort model, enables preemptive thermal system control over a route. A
Hegde, BharatkumarHaskara, IbrahimKaushik, ShailendraChang, ChenFang
Battery electric transit buses sold in Canada generally include a fuel-fired diesel auxiliary heater for cabin heating in cold weather. This report details a test project, performed in collaboration with OC Transpo, to capture and quantify the emissions from such a fuel-fired heater (FFH) installed on a New Flyer XE40 battery electric transit bus from OC Transpo’s fleet in Ottawa, Canada. The FFH was tested while the bus was both stationary and being driven on-road in cold conditions. The results include the emissions rates of carbon dioxide, carbon monoxide, nitrogen oxides, hydrocarbons and methane, and soot. Additionally, total particulate matter results were obtained during stationary testing. The results of stationary testing were compared to the California Air Resources Board and European Union standards for FFH emissions, even though these standards do not apply directly to buses operated outside of these jurisdictions. During stationary testing, average emissions of carbon
Humphries, KieranRashid, HusseinAraji, Fadi
This work aims to develop potential super hydrophilic cross-linked smart polymer composites and condensation management device (CMD) for condensation control in automotive headlamps. Condensation and moisture buildup in the automotive headlamp decrease the visibility to the driver. The super hydrophilic cross-linked polymer composites were prepared with the combination of polyacrylamide-based hydrogels and hygroscopic lithium bromide desiccants. In this work, we have utilized various desiccants such as calcium chloride (Desiccant-1), silica gel (Desiccant-2) and lithium bromide (Desiccant-3) which is blended together with the polyacrylamide-based hydrogel. The prepared various compositional smart materials have been analyzed for structural, morphological, thermal and functional properties using fourier transform infrared spectroscopy (FTIR), optical microscopy (POM), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), differential scanning calorimeter (DSC) and water
Chandkoti, IkhlasNaikwadi, AmolMali, Manoj
One of the important aspects to consider at the design stage is the condensation of water vapor inside the lighting system, under specific weather conditions of temperature and humidity, which may compromise the device functionality. Condensation of water vapor is an issue affecting functional and aesthetics of Head Lamp. The current paper analyses the process of water vapor condensation inside an automotive LED head lamp. This paper also discusses the design methodology to avoid condensation under certain conditions. Design methodology includes design considerations for better air movement for thermal management, material selection, ease of moisture exchange, breather or vent selection, Vent placement. Additionally, this paper would also discuss about effective use of simulations tools, test methods and assembly process guidelines to avoid impact due to condensation. This paper would consist of one example with application of above methodology, its test and field results
Rane, Sandeep BaluPawar, Nishant
Knowing the tire pressure during driving is essential since it affects multiple tire properties such as rolling resistance, uneven wear, and how prone the tire is to tire bursts. Tire temperature and cavity pressure are closely tied to each other; a change in tire temperature will cause an alteration in tire cavity pressure. This article gives insights into which tire temperature measurement position is representative enough to estimate pressure changes inside the tire, and whether the pressure changes can be assumed to be nearly isochoric. Climate wind tunnel and road measurements were conducted where tire pressure and temperature at the tire inner liner, the tire shoulder, and the tread surface were monitored. The measurements show that tires do not have a uniform temperature distribution. The ideal gas law is used to estimate the tire pressure from the measured temperatures. The results indicate that of the compared temperature points, the inner liner temperature is the most
Hyttinen, JukkaUssner, MatthiasÖsterlöf, RickardJerrelind, JennyDrugge, Lars
Autonomous cars (ACs) and advanced driver-assistance systems (ADAS) have relied on convolutional neural networks (CNNs) for object detection. However, image degradation caused by adverse weather conditions like rain, snow, and fog can decrease the performance of a CNN. So, this paper presents the development of an image-processing technique aimed to mitigate such a problem. First, after an extensive evaluation of models for object detection, YOLOv3 was chosen because of its compromise between precision and inference time. Afterwards, the training and test of a YOLOv3 CNN was investigated for cars, traffic signals, traffic lights, pedestrians, and riders. Performance was evaluated by estimating the average and mean average precision (mAP) for every one of the mentioned object classes. An OpenCV based pre-processing technique to mitigate the degradation imposed by adverse weather conditions was implemented. Specifically, the OpenCV filters of erosion, dilation and joint bilateral filter
Romão, BrunoFagotto, Eric
Many learning-based methods estimate ego-motion using visual sensors. However, visual sensors are prone to intense lighting variations and textureless scenarios. 4D radar, an emerging automotive sensor, complements visual sensors effectively due to its robustness in adverse weather and lighting conditions. This paper presents an end-to-end 4D radar-visual odometry (4DRVO) approach that combines sparse point cloud data from 4D radar with image information from cameras. Using the Feature Pyramid, Pose Warping, and Cost Volume (PWC) network architecture, we extract 4D radar point features and image features at multiple scales. We then employ a hierarchical iterative refinement approach to supervise the estimated pose. We propose a novel Cross-Modal Transformer (CMT) module to effectively fuse the 4D radar point modality, image modality, and 4D radar point-image connection modality at multiple scales, achieving cross-modal feature interaction and multi-modal feature fusion. Additionally
Lu, ShouyiZhuo, GuirongXiong, LuZhou, MingyuLu, Xinfei
Items per page:
1 – 50 of 3984