Browse Topic: Water

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This Aerospace Information Report (AIR) outlines the design considerations and criteria for the control of water carryover from the environmental control system (ECS) with respect to causes and indicated corrective or preventative action. In addition, condensation on structure will be reviewed with possible preventative action described
AC-9 Aircraft Environmental Systems Committee
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
The improvement of vehicle soiling behavior has increasing interest over the past few years not only to satisfy customer requirements and ensure a good visibility of the surrounding traffic but also for autonomous vehicles, for which soiling investigation and improvement are even more important due to the demands of the cleanliness and induced functionality of the corresponding sensors. The main task is the improvement of the soiling behavior, i.e., reduction or even prevention of soiling of specific surfaces, for example, windows, mirrors, and sensors. This is mostly done in late stages of vehicle development and performed by experiments, e.g., wind tunnel tests, which are supplemented by simulation at an early development stage. Among other sources, the foreign soiling on the side mirror and the side window depend on the droplet detaching from the side mirror housing. That is why a good understanding of the droplet formation process and the resulting droplet diameters behind the side
Kille, LukasStrohbücker, VeithNiesner, ReinholdSommer, OliverWozniak, Günter
This SAE Aerospace Standard (AS) covers water conditioning agents used to facilitate aqueous wet-method magnetic particle inspection
AMS K Non Destructive Methods and Processes Committee
Brazil has a robust agricultural sector; however, the mechanization of crops causes several problems in the physical soil structure, including surface compaction. Compaction reduces crop productivity and producer profits. The intensity of compaction varies depending on the wheelset model used, tire type, water content, and soil load applied. Recent studies have shown that soil compaction in sugarcane can be attenuated by maintaining the vegetation cover (straw biomass) on the surface after harvesting. The present study used different tire models to evaluate the interaction between wheelset-soil as a function of different amounts of biomass left over from the sugarcane harvest. A physical simulation system (fixed tire testing unit) was used for the tests. The wheelsets were subjected to controlled loads on tanks with confined and standardized soil samples. The treatments consisted of 3 tire models (p1: road radial, composed of double wheelset - 2×275/80R22.5; p2: agricultural radial
Filho, Aldir Carpes MarquesSartorio, Simone D. M.Martins, Murilo B.Lanças, Kléber P.
A research team has developed diamond quantum sensors that can be used to improve resolution in magnetic imaging. In order to test the method, the scientists placed a microchip with microscopic water-filled channels on the diamond quantum sensor. This allowed the researchers to simulate microstructures of a cell. They were able to successfully analyze the diffusion of water molecules within the microstructure
Composite materials find extensive applications in numerous fields, including mechanical components, which are often subjected to varying climatic conditions. Due to the contrasting conditions, there is a difference in the external loadings, leading to the transfer of air, heat, and moisture between the environments. Here, the study is done to model the moisture-based diffusion in order to predict the output beforehand so that necessary precautions can be taken before it fails. The study primarily investigates the heat and moisture-based absorption behavior of composite materials. The Representative Volume Element (RVE) approach is chosen, which enables the simulation of the behavior of the composite at a microscale level, giving insights into the micromechanics and analyzing the material absorption behavior of moisture. The FEA approach for the same is carried out using the COMSOL Multiphysics software. The required RVE of the composite is modeled, and the effect of fiber volume
Nelson, N Rino
In today's world, there is an increasing emphasis on the responsible use of fiber reinforced materials in the automobile applications, construction of buildings, machinery, and appliances as these materials are effectively reused, recycled, or disposed with minimum impact on the environment. As such, it has become mandatory to incorporate sustainable, environmental friendly and green concepts in the development of new materials and processes. The primary objective of this study is to manufacture composites using fibers obtained from Thespesia Lampas plants, which are known for their soft, long fibers that are commonly used in various domestic products. The composites are made by combining these fibers with a general purpose polyisocyanurate resin, and their potential applications in both domestic and commercial products are explored. To evaluate the properties of these composites, tests are conducted for tensile strength, flexure, and water absorption. The laminates are fabricated
Somsole, Lakshmi NarayanaNatarajan, ManikandanPasupuleti, ThejasreeN, Anantha KrishnaKatta, Lakshmi Narasimhamu
NASA engineers have developed a new approach to mitigating unwanted motion in floating structures. Ideally suited to applications including offshore wind energy platforms and barges, the innovation uses water ballast as a motion damping fluid
NASA instrumentation is at risk for contamination from dusty space environments. Additionally, contamination from water and ice buildup can affect instrumentation function. Researchers at the Goddard Space Flight Center have developed a viable dust, water, and ice mitigation optical coating for space flight, aeronautical, and ground applications. The innovation of the LOTUS coating prevents contamination on sensitive surfaces, like optics, that cannot be cleaned during space missions
The demand for multi-environmental modes of transportation is driven by the overall trend of increasing mobility and the necessity of movement across various alternating environments (land, water, underwater, aerial, and airspace). However, the specific energy density of hydrocarbon fuels cannot ensure efficient operation of power systems for such multi-environmental vehicles. A promising solution to this problem involves the utilization of boron-containing metallized fuels through the creation of specialized fuel supply systems. Based on a general method of optimization synthesis for technical objects, new fuel supply systems were synthesized with different levels of process control and degrees of automation, as well as an adjustable hybrid fuel delivery system that allows the application of components in varying aggregate states. During testing, operational characteristics were determined primarily for the implemented metallic hybrid transformer fuel delivery system. In our view, it
Dudukalov, YuriTernyuk, MykolaHlushkova, DianaBushnov, ValerySorokin, VolodymyrKholodov, Mykhailo
The growing demand for transportation fuels and the global emphasis on reducing greenhouse gas (GHG) emissions have led to increased interest in analyzing transport GHG emissions from the life-cycle perspective. Methanol, a potentially carbon-neutral fuel synthesized from CO2 and H2, has emerged as a promising candidate. This paper conducts a comprehensive life-cycle analysis (LCA) of the GHG emissions associated with the methanol production process, utilizing data inventory from China in 2019. To simulate the synthesis and distillation process of methanol, Aspen Plus is employed, using parameters obtained from actual plants. GHG emissions are then calculated using the GREET model, incorporating updated industry statistics and research findings. The CO2 necessary for methanol production is captured from factory flue gas. Two different sources of H2 are considered: one from Coke Oven Gas (COG) and the hydrogen-rich gas byproduct resulting from COG methanation (Case 1), and the other via
Fu, YangWang, BuyuShuai, Shijin
As engine technology developed continuously, engine with both turbocharging and EGR has been researched due to its benefit on improving the engine efficiency. Nevertheless, a technical issue has raised up while utilizing both turbocharging and EGR at the same time: excess condensed water existed in intake manifold which potentially trigger misfire conditions. In order to investigate the root-cause, a CFD model (conducted by CONVERGE CFD software) was presented and studied in this paper which virtually regenerated intake manifold flow-field with EGR condensed water inside. Based on the simulated results, it concluded that different initial conditions of EGR condensed water could significantly change the amount of water which deposited in each cylinder. Thus, a coefficient of variation of deposited condensed water amount among these cylinders, was marked as the evaluation reference of cylinder misfire. Theoretically, as this coefficient of variation reduced, the EGR condensed water from
Pan, ShiyiLi, GuantingWang, JinhuaZhang, NanXu, ZhiqinChen, ShanghuaChen, JunZhao, Shengwei
Dubbed an “engineered living material,” a new type of material developed at the University of California San Diego could offer a sustainable and eco-friendly solution to clean pollutants from water
A Northwestern University research team has developed a revolutionary transistor that is expected be ideal for lightweight, flexible, high-performance bioelectronics. The electrochemical transistor is compatible with blood and water and can amplify important signals
Personal devices feed our sight and hearing virtually unlimited streams of information while leaving our sense of touch mostly … untouched
Researchers from Northwestern University have collaborated on the implementation of an accurate, low-cost, and easy-to-use test for detecting toxic levels of fluoride in water. The new biosensor device has been field tested in Kenya — proving that testing water for fluoride can be easily accomplished outside of a lab and accurately interpreted by nonexperts
Photosynthesis has evolved in plants for millions of years to turn water, carbon dioxide, and the energy from sunlight into plant biomass and the foods we eat. This process, however, is very inefficient, with only about 1 percent of the energy found in sunlight ending up in the plant. Scientists at UC Riverside and the University of Delaware have found a way to bypass the need for biological photosynthesis altogether and create food independent of sunlight by using artificial photosynthesis
Recently, lean manufacturing (LM) practices are being combined with tools and techniques that belong to other areas of knowledge such as risk management (RM). Value stream mapping (VSM) is a well-known tool in showing the value, the value stream, and the flow, which represents the three lean principles. VSM and RM, when used in tandem with one another, are more advantageous in covering VSM issues such as the variability of production processes. In this article, a conceptual model that integrates the two is shown and explained. The model helps to generate scenarios of current state map (CSM) and future state map (FSM) in a dynamic way by identifying current and potential risks. These risks might happen in the future, bringing with it negative ramifications including not reaching the main objectives within the defined time. The model has been tested in a coffee production company belonging to health and food sector. The proposed model specified the ranges of variability through the
Araibi, Alaa SalahuddinShaiful, A. I. M.Shadhar, Mohanad Hatem
More than half a century has passed since the birth of quantum signal detection theory, which is the cornerstone of modern quantum communication theory. Quantum stream cipher, the quantum-noise-based direct encryption scheme for optical communications at the center of our research, is based on the foundations of quantum communication theory. For quantum cryptography to progress from a theoretical possibility to a more realistic technology, experimental and theoretical research must be complementary
Exploring the possibility of all-weather secure quantum communication using macroscopic quantum states of light. Air Force Research Laboratory, Asian Office of Aerospace Research and Development, Tokyo, Japan More than half a century has passed since the birth of quantum signal detection theory, which is the cornerstone of modern quantum communication theory. Quantum stream cipher, the quantum-noise-based direct encryption scheme for optical communications at the center of our research, is based on the foundations of quantum communication theory. For quantum cryptography to progress from a theoretical possibility to a more realistic technology, experimental and theoretical research must be complementary. We have reported several experimental and theoretical studies on the quantum stream cipher connecting two points via optical fibers and also fabricated a prototype based on them. To enhance the usability of a quantum stream cipher, free-space optical communications must be explored in
As emission restrictions become more stringent and conventional fuel supplies become more limited, dual-fuel engines are emerging as a promising solution that offers both environmental and economic benefits. However, the performance of these engines is often hampered by the issue of knocking, which can negatively impact their overall operation, and also by the increase in NOx emissions at high load. This work investigates the use of pilot injection properties by combining the use of emulsified diesel of different water percentages with injection timing to reduce both knock intensity and NOx emission rate. Specifically, a dual fuel operation case at full load with high enrichment of the primary fuel (natural gas) with hydrogen is considered in order to create conditions for high knocking and high NOx emission rates. The online optimization principle is used for the creation of the meta-model, utilizing the Radial Basis Functions technique (RBF), and the search for the optimum in
Sehili, YoucefLoubar, KhaledTarabet, LyesMahfoudh, CerdounLacroix, Clément
As rains get heavier and more frequent, flooding, especially in cities, is becoming a serious problem. The traditional way of managing stormwater has been to quickly get it off the road and into the storm sewer system to be sent downstream, said Lauren McPhillips, Assistant Professor of civil and environmental engineering and of agricultural and biological engineering at Penn State. “With the stormwater out of sight, the problem was out of mind.” However, whisking the water away increases risks of extreme flooding downstream
Most of the world is covered in oceans, which are unfortunately highly polluted. One of the strategies to combat the mounds of waste found in these very sensitive ecosystems — especially around coral reefs — is to employ robots to master the cleanup. However, existing underwater robots are mostly bulky with rigid bodies, unable to explore and sample in complex and unstructured environments, and are noisy due to electrical motors or hydraulic pumps. For a more suitable design, scientists at the Max Planck Institute for Intelligent Systems (MPI-IS) in Stuttgart looked to nature for inspiration
This specification covers a stable, noncorrosive, water-soluble, highly-penetrating, fluorescent solution which may, but need not, be diluted with an appropriate amount of water for use
AMS K Non Destructive Methods and Processes Committee
Multiphase CFD simulations of air and water play a critical role in aircraft icing analysis. Specifically for air data sensors mounted near the front of an aircraft, simulations that predict the concentration of water surrounding an aircraft fuselage are necessary for understanding their performance in icing conditions. Those simulations can aid in sensor design and placement, and are central for defining critical conditions to test during icing qualification campaigns. There are several methods available in CFD that solve a multiphase flow field. Two of the most common methods used are Lagrangian and Eulerian. While these methods are similar, important differences can be viewed in the results, specifically in how the water shadow zones are predicted. This paper compares a Lagrangian and Eulerian CFD method for solving a multiphase flow field, and assesses their performance for use for analyzing installation locations and critical icing conditions of air data probes
Thangavel, SathishCusher, Aaron
To support an industry wide response to an EASA proposed Special Condition regarding the threat of in-flight supercooled liquid water icing conditions at altitudes above FL300, Boeing 777 fleet data were used to estimate the frequency and severity of such icing occurrences. The data were from the calendar year 2019 and included ~ 950,000 airline revenue flights from around the world by multiple operators. The unique architecture of the Primary Ice Detection System (PIDS) on that model, in addition to robust meteorological data that was able to be correlated, afforded an opportunity to conservatively estimate the Total Water Exposure (TWE) and thus the Liquid Water Content (LWC) of the icing encounters captured at FL295 and above. This paper will outline the key methods used and present the findings
Sanford, JeromeBravin, MelissaClarkson, MatthewNatsui, Edward
Future compliance to FAA 14 CFR Part 25 and EASA CS-25 Appendix O conditions has required icing wind tunnels to expand their cloud simulation envelope, and demonstrate accurate calibration of liquid water content and droplet particle size distributions under these conditions. This has led to a renewed community interest in the accuracy of these calibrations, and the potential inter-facility bias due to the choice of instrumentation and processing methods. This article provides a comparison of the response of various hot-wire liquid water content instruments under Appendix C and supercooled large droplet conditions, after an independent similar analysis at other wind tunnel facilities. The instruments are being used, or are under consideration for use, by facilities collaborating in the ICE GENESIS program. For droplet median volume diameters (MVDs) between about 15 and 250 μm, cylindrical hot wire LWC sensors were found to consistently and increasingly under-read measurements from
Esposito, Biagio M.Orchard, DavidLucke, JohannesNichman, LeonidBliankinshtein, NataliaLilie, LyleCatalano, PietroD'Aniello, FrancescoStrapp, J. Walter
Thermal ice protection systems (IPS) are used extensively in aeronautics. They are tailored according to the aircraft characteristics or flight envelope and can be used in different modes, anti-icing to avoid ice accretion or de-icing to remove the ice once accreted. A relevant issue by this application is the runback icing, caused by the downstream flow of melted or running water to unprotected areas, where activation is not possible in terms of energy consumption. Passive systems are being explored to complement or replace active systems, although, up to now, solutions have not been reported with the required performance for real-life applications. One of the most commonly reported anti-icing strategy relays on superhydrophobicity, i.e., it is based on the water roll-off capacity of Cassie-Baxter superhydrophobic surfaces (CB-SHP). Precisely, running wet phenomena, where liquid water is flowing on the surface, could be an appropiate application field for this type of materials
Mora, JulioGarcía, PalomaCarreño, FranciscoMontes, LauraLópez-Santos, CarmenRico, VictorBorras, AnaRedondo, FranciscoGonzález-Elipe, Agustín R.Agüero, Alina
Threats to aviation safety as a result of super-cooled large drops (SLD) has been addressed by the FAA rules change (14 CFR Part 25) with the additional icing certification requirement. SLD clouds often consist of bi-modal drop size spectra leading to significant problems in simulating and characterizing these conditions in situ and in icing wind tunnels. Legacy instrumentation for measuring drop size distributions and liquid water content are challenged under these conditions. The large size range measurement problem is addressed with the development of the Phase Doppler Interferometer, Flight Probe Dual-Range (PDI FPDR). The method is described in this report along with the measurement capabilities including the dynamic measurement range and overall working size range. The PDI instrument bases drop size measurements on the light wavelength as the measurement length scale. The light wavelength is a much more robust scale, especially as compared to the light scattering intensity
Bachalo, William DonPayne, GregoryIbrahim, KhalidFidrich, Michael
Considerable amounts of water accumulate in aircraft fuel tanks due to condensation of vapor during flight or directly during fueling with contaminated kerosene. This can result in a misreading of the fuel meters. In certain aircraft types, ice blocks resulting from the low temperatures at high altitude flights or in winter time can even interfere with the nozzles of the fuel supply pipes from the tanks to the engines. Therefore, as part of the maintenance operations, water has to be drained in certain intervals ensuring that no remaining ice is present. In the absence of an established method for determining residual ice blocks inside, the aircraft operator has to wait long enough, in some cases too long, to start the draining procedure, leading potentially to an unnecessary long ground time. A promising technology to determine melting ice uses acoustic signals generated and emitted during ice melting. With acoustic emissions, mainly situated in the ultrasonic frequency range, a very
Pfeiffer, HelgeReynaert, JohanSeveno, DavidJordaens, Pieter-JanCeyhan, OzlemWevers, Martine
The Icing Research Tunnel at NASA Glenn follows the recommended practice for calibration outlined in SAE’s ARP5905. The calibration team has followed the schedule of a full calibration every five years with a check calibration done every six months following. The liquid water content of the IRT has maintained stability within the stated specifications of variation within +/- 10% of the curve fit equation generated from calibration data. Using past measurements and data trends, IRT characterization engineers wanted to develop methods for the ability to know when data were not within variation. Trends can be observed in the liquid water content measurement process by constructing statistical process control charts. This paper describes data processing procedures for the Multi-Element Sensor in the IRT, including collision efficiency corrections, canonical correlation analysis, process for rejection of data, and construction of control charts. Data are presented to display the control
Timko, EmilyKing-Steen, LauraInsana, Eric
This paper is focused on the numerical analysis of the impingement and water catch rate of snow particles on the engine air intake of the Next Generation Civil Tilt Rotor (NGCTR). This NGCTR is developed by Leonardo Helicopters. The collection efficiency and water catch rate for the intake geometry are obtained for the test cases that have been defined for the relevant snow conditions. These conditions are related to the flight envelope of the NGCTR, existing EASA/FAA certification specifications, and the snow characterization. The analyses have been performed for the baseline air intake geometry. A range of particle diameters has been simulated with a particle density equal to the density of ice and with a particle drag relation that disregards the particle shape. Based on the results for the water catch rate on the basic nacelle configuration in snow conditions it is concluded that the ‘cheeks’ of the duct are more susceptible to impingement of larger snow crystals (>75 μm), whereas
Kool, NinaVan der Weide, EdwinSpek, Ferdinandvan der Ven, Harmenvan 't Hoff, Stefan
A fundamental understanding of the icing process for aircraft requires a more thorough analysis of the thermodynamics of supercooled droplet impingement. To better study such thermodynamic processes, a novel temperature sensor that functions within supercooled water and ice crystals was developed. The temperature sensor is non-intrusive and provides temperature and phase change information for both liquid water and solid ice. The temperature sensor is an optical sensor based on the luminophore pyranine. The use of pyranine allows for the measurement of spatially and temporally resolved temperature fields for icing applications. The sensitivity of the sensor is -9.2±0.1%/K for temperature measurement in the solid phase and 0.8±0.1%/K for the liquid phase. The performance of the sensor was demonstrated through a calibration process using spectral analysis, the observation of the melting process of a rectangular prism created from the luminescent ice, and the study of the temperature
Gonzales, JosephYamazaki, MasafumiSakaue, Hirotaka
In the framework of the European ICE GENESIS project (https://www.ice-genesis.eu/), a field experiment was conducted in the Swiss Jura in January 2021 in order to characterize snow microphysical properties and document snow conditions for aviation industry purposes. Complementary to companion papers reporting on snow properties, this study presents an investigation on mixed-phase conditions sampled during the ICE GENESIS field campaign. Using in situ measurement of the liquid and total water content, the ice mass fraction is calculated and serves as a criteria to identify mixed-phase conditions. In the end, mixed phase conditions were identified in almost 30 % of the 3800 km long cloud samples included in the ICE GENESIS dataset. The data suggests that the occurrence of mixed-phase does not clearly depend on temperature in the 0 to -10 °C range, but varies significantly from one cloud system to another. The distribution of mixed phase and liquid only spatial scales cascades from 100 m
Coutris, PierreFebvre, GuyJaffeux, LouisSchwarzenboeck, AlfonsDezitter, FabienBillault-Roux, Anne-ClaireGrazioli, JacopoBerne, AlexisJorquera, SusanaDelanoe, Julien
In the last decades there have been many temporary engine failures, engine-related events and erroneous airspeed indication measurements that occurred by a phenomenon known as Ice Crystal Icing (ICI). This type of icing mainly occurs in high altitudes close to tropical convection in areas with a high concentration of ice crystals. Direct measurements or in-situ pilot observations of ICI that could be used as a warning to other air-traffic are rare to nearly non-existent. To detect those dangerous high Ice Water Content (IWC) areas with already existing airborne measurement instruments, Lufthansa analyzed observed Total Air Temperature (TAT) anomalies and used a self-developed search algorithm, depicting those TAT anomalies that are related to ice crystal icing events. To optimize the flight route for dispatchers several hours before the flight, e.g. for long distance flights through the intertropical convergence zone (ITCZ), reliable forecasts to identify hazardous high IWC regions are
Kalinka, FrankButter, MaxJurkat, TinaDe La Torre Castro, ElenaVoigt, Christiane
The paper describes a tools’ suite able of analyzing numerically 3D ice-accretion problems of aeronautical interest. The methodology consists of linking different modules each of them performing a specific function inside the ice-simulation chain. It has been specifically designed from the beginning with multi-step capability in mind. Such a feature plays a key role when studying the dynamic evolution of the icing process. Indeed, the latter has the character of a multi-physic and time-dependent phenomenon which foresees a strong interaction of the air- and water fields with the wall thermodynamics. Our multi-layer approach assumes that the physical problem can be discretized by a series of pseudo-steady conditions. The simulation process starts with the automatic generation of a Cartesian three-dimensional mesh which represents the input for the immersed boundary (IB) RANS solver. Once obtained, the air-phase is used by the Eulerian tool to solve the transport of the water-phase on
de Rosa, DonatoCapizzano, FrancescoCinquegrana, Davide
This work presents the implementation and validation efforts of a 3D ice accretion solver for aeronautical applications, MESS3D, based on the advanced Messinger model. The solver is designed to deal with both liquid phase and ice crystal cloud conditions. In order to extend the Messinger model to 3D applications, an algorithm for the water run-back distribution on the surface was implemented, in place of an air flow stagnation line search algorithm, which is straightforward in 2D applications, but more complicated in 3D. The developed algorithm aims to distribute the run-back water in directions determined by air pressure gradients or shear forces. The data structure chosen for MESS3D allows high flexibility since it can manage the necessary input solutions on surface grids coming from both structured and unstructured solvers, regardless the number of edges per surface cells. The aim of the work is to present a validation of the model by examining the robustness of the solutions when
Cinquegrana, DavideD'Aniello, Francescode Rosa, DonatoCarozza, AntonioCatalano, PietroMingione, Giuseppe
In 2017 the National Research Council of Canada developed an evaporation model for controlling engine icing tunnels in real time. The model included simplifications to allow it to update the control system once per second, including the assumption of sea level pressure in some calculations. Recently the engine icing system was required in an altitude facility requiring operation down to static temperatures of -40°C, and up to an altitude of 9.1 km (30 kft) or 30 kPa. To accommodate the larger temperature and pressure range the model was modified by removing the assumption of sea level operation and expanding the temperature range. In addition, due to the higher concentration of water vapor that can be held by the atmosphere at lower pressures, the significance of the effect of humidity on the air properties and the effect on the model was investigated. The effect of humidity on the density, specific heat, viscosity, thermal conductivity and Prandtl number of air compared to assuming
Davison, Craig
Ice and snow accretion on aircraft surfaces imposes operational and safety challenges, severely impacting aerodynamic performance of critical aircraft structures and equipment. For optimized location-based ice sensing and integrated ‘smart’ de-icing systems of the future, microwave resonant-based planar sensors are presented for their high sensitivity and versatility in implementation and integration. Here, a conformal, planar complementary split ring resonator (CSRR) based microwave sensor is presented for robust detection of localized ice and snow accretion. The sensor has a modified thick aluminum-plate design and is coated with epoxy for greater durability. The fabricated sensor operates at a resonant frequency of 1.18 GHz and a resonant amplitude of -33 dB. Monitoring the resonant frequency response of the sensor, the freezing and thawing process of a 0.1 ml droplet of water is monitored, and a 60 MHz downshift is observed for the frozen droplet. Using an artificial snow chamber
Shah, AaryamanNiksan, OmidZarifi, Mohammad H.
Products for nautical applications face an unusual set of design challenges. The corrosiveness of salt water can cause premature degradation, and the impact of fast-moving vessels bouncing up against forceful ocean waves can also damage equipment
More than five million people in the United States live with some form of paralysis and may encounter difficulties completing everyday tasks, like grabbing a glass of water or putting on clothes. New research from Carnegie Mellon University’s Robotics Institute (RI) aims to increase autonomy for individuals with such motor impairments by introducing a head-worn device that will help them control a mobile manipulator
The prevailing mission-based paradigm for ocean color remote sensing typically involves high-cost satellite platforms launched and operated by government agencies such as NASA, NOAA, ESA, and JAXA. These platforms host state-of-the-art ocean-viewing radiometers with design and sensitivity specifications appropriate for delineating a comparatively weak water-leaving radiance from the total radiant signal detected at the top of the atmosphere. The current suite of such operational ocean color sensors includes NASA’s Moderate Resolution Imaging Spectroradi-ometer (MODIS; Aqua satellite), NOAA’s VIIRS (SNPP and NOAA-20 satellites), the Ocean and Land Color Instrument (OLCI; Sentinel-3 A/B satellites), and the Second-Generation Global Imager (SGLI) onboard the GCOM-C satellite. All of these sensors provide multi-spectral band sets (visible, near-infrared (NIR), and shortwave infrared (SWIR)) with daily coverage at approximately kilometer-scale spatial resolution. However, even kilometer
An automotive door latch that functions manually or electronically is a vital component of a door closure system. It primarily aims to provide security of the occupants by securing the door system by ensuring timely locking and unlocking of the doors. A wide range of factors like safety, ergonomics, and security influence the development of these latches to eliminate safety. With the growing trend and advancements, automotive electronics is becoming more complex and prevalent. Hence, any exposure of electrical/electronic components to water make them susceptible to short circuits, corrosion etc., thereby may make it the functionality of systems and increasing the chances of failure in these devices. Intrusion of water possible into the latch system can be disastrous depending on the climatic conditions. Stringent safety criteria have given rise to unconventional test methods that are time-consuming and hence necessitate virtual validation techniques. Virtual validation becomes a viable
Kaushik, AchalaKrishnamurthy, HarishGajendra, HarishCalamaco, Eli
In an automotive vehicle, the Window Regulator is an electro-mechanical assembly that is mounted inside the door. The basic function of the Window Regulator is to raise or lower the glass when required and hold the glass in closed position or in any desired position. During Water servicing or rains, Water will typically enter inside the door through the seals and on to the Window Regulator mechanism. Hence these conditions must be physically tested in the laboratory to assess the Window Regulator’s functionality which could get affected by Water intrusion. The Water spray test conditions are based on mutual agreement between Inteva Products and the OEMs. Water spray test involves moving the electric Window Regulator to upper stall position (Window closed) at a defined voltage and line resistance. The glass must be dwelled followed by spraying defined amount of Water which simulates the rain. The agreed number of test cycles would be around 4500 which lasts about 7 weeks. Hence, to
Gavhane, SudarshanBabu, YugandharPrasannakumar, JitheshBanjan, Rohith
A team of researchers at University of California, Riverside, has moved a step closer to finding a use for the hundreds of millions of tons of plastic waste produced every year that often winds up clogging streams and rivers and polluting our oceans
The requirements of the automotive industry move along due to product competitiveness and this contributes to increase complexity in the requirements for evaluation. Simulation tools play a key role thanks to their versatility and multiple physical phenomena that can be represented. The axis of analysis for this paper is the problem of the interaction of airflow and water flow in the cowl/plenum/leaf screen components. Airflow is represented by HVAC system operating and water flow by the vehicle in torrential rain. Initially, one simulation is evaluated at a time, in one side, the airflow entering the HVAC system in which the amount of air entering is monitored and pressure drop, on the other, the water simulation on the vehicle, both using a Lagrangian CFD model (using with tools such as STAR CCM+® or Ansys Fluent®) Due to this, a CFD methodology was developed to evaluate the interaction of air and water flow. This uses CFD Eulerian model for airflow and a Lagrangian model for water
Alonso, LilianaSaavedra, OscarRuiz, Josias
Advanced driver assistance systems rely on external sensors that encompass the vehicle. The reliability of such systems can be compromised by adverse weather, with performance hindered by both direct impingement on sensors and spray suspended between the vehicle and potential obstacles. The transportation of road spray is known to be an unsteady phenomenon, driven by the turbulent structures that characterise automotive flow fields. Further understanding of this unsteadiness is a key aspect in the development of robust sensor implementations. This paper outlines an experimental method used to analyse the spray ejected by an automotive body, presented through a study of a simplified vehicle model with interchangeable rear-end geometries. Particles are illuminated by laser light sheets as they pass through measurement planes downstream of the vehicle, facilitating imaging of the instantaneous structure of the spray. The tested configurations produce minor changes to the flow field, the
Crickmore, Conor JamesGarmory, AndrewButcher, Daniel
Fuel cells are considered one of the promising technologies as possible replacement of Internal Combustion Engine (ICE) for the transportation sector due to their high efficiency, ultra-low (or zero) emissions and for the higher drive range. The Membrane Electrode Assembly (MEA) is what mainly influences the Fuel Cell FC performance, durability, and cost. In PEMFC the proton conductivity of the membrane is a function of the humidification level of the FC membrane, hence the importance of keeping the membrane properly humidified to achieve the best possible fuel cell performance. To have the optimal water content inside the fuel cell’s membrane several strategies could be adopted, dealing with the use of external device (such as membrane humidifier) or to adopt an optimal set of parameters (gas flow rate and temperature for example) to use the water produced at fuel cell cathode as humidity source. The aim of this paper is to study the behavior of a FC vehicle humidification system
Carello, MassimilianaLandolfi, SilvioRizzello, AlessandroKhadilkar, Sumit
Proton Exchange Fuel Cells (PEMFCs) are considered one of the most prominent technologies to decarbonize the transportation sector, with emphasis on long-haul/long-range trucks, off-highway, maritime and railway. The flow field of reactants is dictated by the layout of machined channels in the bipolar plates, and several established designs (e.g., parallel channels, single/multi-pass serpentine) coexist both in research and industry. In this context, the flow behavior at cathode embodies multiple complexities, namely an accurate control of the inlet/outlet humidity for optimal membrane hydration, pressure losses, water removal at high current density, and the limitation of laminar regime. However, a robust methodology is missing to compare and quantify such aspects among the candidate designs, resulting in a variety of configurations in use with no justification of the specific choice. This contrasts with the large operational differences, especially regarding the pressure loss
Corda, GiuseppeCucurachi, AntonioDiana, MartinoFontanesi, StefanoD'Adamo, Alessandro
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