Ice Detectors Research Articles

Experimental study on the technology optimization of clear ice thickness detection on horizontal cold plate surface by using microwave resonance

The accumulation of snow and ice has the potential to have a negative impact on numerous industries if it is not accurately detected and processed in real-time. Microwave resonators have gained interest as durable and reliable ice detectors. To detect the thickness of clear ice slices on a horizontal cold plate surface, a capacitively coupled split-ring resonant sensor was experimentally investigated. To ascertain the efficacy of the sensor, plexiglass with similar relative permittivity to ice was firstly tested. The effect of the plexiglass plate thickness on the resonance amplitude of the transmission scatter parameter was found to be monotonic in the range of 16.8 mm thickness, thereby demonstrating the ability of the sensor to accurately measure plate thickness. Then, the effect of different thicknesses of clear ice slices within 17.0 mm on the resonance parameters was tested under constant temperature. The resonant amplitude decreased by 46.55% from −4.13 dB to −6.05 dB, as the thickness of the clear ice slice gradually increased from 2.5 mm to 17.0 mm. A model for the detection of ice thickness based on the analysis of theoretical principles and experimental data was developed. The ice thickness could be detected accurately within a range of 17.0 mm at temperatures between −3 and −20 °C, with a maximum deviation of 5.66% in the detection of ice thickness. This study validates the application of the sensor to detect ice thickness, such as on ships, roads and aircraft.

Ice growth detection and the de-icing using dual functional capacitive sensor

Ice detectors are vital for ice mitigation systems, ensuring accurate ice growth measurements across multiple icing-de-icing cycles. Residue ice on the sensor can lead to erroneous readings in subsequent cycles, so its removal is critical to obtain accurate readings. This article presents a novel capacitive ice detector with self-deicing functionality employing nichrome electrodes for both sensing and de-icing. The sensor underwent testing in a cooling chamber for validation. The results confirm the developed ice detector’s ability to quantify ice within 1 to 4 mm with up to 7.5 % error, while the de-icing unit consumes 35 W to remove a 2 mm ice layer in 60 s. Capacitive sensor de-icing can significantly enhance the performance of ice mitigation systems. This research significantly advances ice detection technology by providing a reliable method for accurate ice measurement and removal, offering a valuable foundation for future improvements in the field of ice mitigation systems.

Research on ice shedding experiment for large civil aircraft to exit ice protection mode

While aircraft flying, once the icing detector finds the icing environment, the stall protection system will turn on the icing stall protection mode. After aircraft leaves the icing environment, due to the lack of effective means to determine whether there is still ice on the unprotected surface of the aircraft, it is impossible to exit the icing stall protection mode, which can lead to issues such as high approach speed of the aircraft, affecting landing safety and passenger comfort. To solve this problem, this paper conducts experimental research on ice shedding time under different temperature conditions, simulating the phenomenon of ice shedding during aircraft fight. This work helps formulate the logic of aircraft exiting icing protection mode, and lays a basis for future work of aircraft performance optimization.

Experimental Study on Optimum Design of Aircraft Icing Detection Based on Large-Scale Icing Wind Tunnel

Icing detection is the premise and basis for the operation of aircraft icing protection system, and is the primary issue in flight safety assurance. At present, there is a lack of research methods and design reference for the layout optimization of ice detectors. Therefore, in order to simulate the real icing environment encountered by the aircraft more accurately, a large-scale icing wind tunnel was used to carry out experimental research on the icing characteristics of the sensor probes. A closed-loop experimental method including the typical condition selection, sensor array interference examination and ice shape repeatability verification was initially proposed. A stepwise optimization process and a sensitivity analysis on ambient conditions were combined to determine the optimal distribution for sensor installation. It is found that the water collection coefficient on the cylinder surface of the probe first increases and then decreases along the axial direction, reaching the extreme value at a certain position. The height of this extreme point will gradually increase with the development of the wall boundary layer, showing a variation range of 2~30 mm. Improper design may cause the sensor probe to fail to capture the point with the maximum icing thickness, affecting the sensitivity of icing detection. In addition, each probe position has different sensitivity to changes in flow parameters; the points with larger icing mass and lower sensitivity to changes in attack angle will have better detection effect. The measured data and analysis in the present work can provide a basis for the accurate design of icing sensor probes.

Pengukuran level pembentukan es (ICING) pada pemodelan menggunakan rancang bangun sensor berbasis perubahan frekuensi dengan induktor datar

Icing is one of the main dangers for the flight and are cumulative. The icing is a process of accumulation of ice on parts of the aircraft, which will lead to changes in geometry and resulted in a variety of other disorders. For example, there was a buildup of ice on the propellor (propeller) and the engine carburetor so it can reduce the thrust plane even caused the plane to fall freely (stall). For it needs to be designed and built the Icing Detector as well as the actuator in providing early warning of the existence of the calculation and the icing on the pilot.
 This instrument is designed with electronic units that use the oscillator as frequency generator and frequency meter based mikrokontroller ATmega8 as the measuring frequency. The surface of the sensor is made up of printed inductor with a broad surface for detection area. Sensors and electronic units connected by cable. In addition, modeling for the pilot indicators have been designed using the LCD.
 Research results suggest that testing on "Ice Accretion-Level Measurement On Modelling using printed Inductor Sensor Prototype Based On Frequency Shifting" has been a successful made in accordance with the expected functions. These instruments can detect the occurrence of icing and give an indication of the thickness of the ice. It is possible to form a flat sensor installation on the aircraft to be more unobtrusive air flow, as well as a spacious surface produces more accurate results.

Modified Microwave Sensor with a Patterned Ground Heater for Detection and Prevention of Ice Accumulation.

Ice accumulation on aircraft is known to negatively impact the aerodynamic and mechanical operation, sometimes resulting in catastrophic failure. Recently, microwave resonators have gained interest as durable and reliable frost and ice detectors. Here, a microwave resonator sensor with built-in heating capability patterned into the ground plane was designed, fabricated, and tested to investigate real-time ice and frost growth. Sensing was performed on surfaces with anti-icing coatings to quantitatively analyze the effectiveness of these materials. The sensor was also tested to determine its ability to evaluate different deicing methods. The sensor itself was a split-ring resonator (SRR) operating at 5.82 GHz, which could effectively distinguish between water and ice by detecting changes in the dielectric properties on or around its surface. This application was particularly suited for an SRR due to the extreme difference between the relative permittivity of water (ε = 90) and ice (ε = 3.2) at 5 GHz and 0 °C. The results from this sensor can be used to determine the holdover time of various coatings to resist ice formation. This study validates the use of SRRs as ice detection sensors for applications where ice and frost are of great interest, such as on aircraft, roads, or walkways.

PROMOTION OF TRANSPORT AIRСRAFT FLIGHT SAFETY TAKING INTO ACCOUNT UPDATED CERTIFICATION REQUIREMENTS FOR ICING CONDITIONS

Due to the implementation of new certification requirements for icing conditions provided in Annex О to CS-25, there is a necessity to analyze the impact of the requirements on the possibility of transport aircraft certification for flights under such conditions. The particularities of such certification requirements and their impact on three main directions of aircraft certification have been considered for icing conditions: icing annunciation system, air data system and anti-icing system. It has been shown that new requirements have no effect on certification of air data system sensors but they have an impact on icing annunciation and antiicing system. Timely annunciation of icing is important for safe operation of aircraft. The procedure providing timing annunciation was developed earlier in Annex C to AR/CS/FAR-25. It is highlighted that this procedure is also actual for new icing conditions but taking into account relevant updates in calculations of the growth of ice accretions on ice detectors, air inlets and lifting surfaces. One of the problems is to detect the moment of coming into icing conditions, determined by new requirements. It substantially determines the possibility of immediate escape from icing area if the airplane does not meet the safe operation requirements for such conditions. The techniques of removing ice accretions from lifting surfaces are described. The case of icing the wing surface behind the slats area with barrier ice accumulation was studied. The possibility of an aircraft limitless operation under icing conditions determined by new certification requirements was estimated.

A new atmospheric icing detector based on thermally heated cylindrical probes for wind turbine applications

This paper presents a new method to detect atmospheric icing conditions using different arrangements of thermally heated and instrumented cylindrical probes. The proposed method offers a new low-cost alternative to detect icing conditions. A mathematical model describing the heat transfer behaviour of each probe has been developed and validated experimentally in a temperature-controlled wind tunnel. In situ measurements under icing conditions have shown great potential for the detection of the onset, the duration and the intensity of an icing event.

Investigation of ice cloud microphysical properties of DCSs using aircraft in situ measurements during MC3E over the ARM SGP site

AbstractSix deep convective systems (DCSs) with a total of 5589 five‐second samples and a range of temperatures from −41°C to 0°C during the Midlatitude Continental Convective Clouds Experiment (MC3E) were selected to investigate the ice cloud microphysical properties of DCSs over the Department of Energy Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) site. The ice cloud measurements of the DCS cases were made by the University of North Dakota Citation II research aircraft, and the ice cloud properties were derived through the following processes. First, the instances of supercooled liquid water in the ice‐dominated cloud layers of DCSs have been eliminated using multisensor detection, including the Rosemount Icing Detector, King and Cloud Droplet Probes, as well as 2DC and Cloud Imaging Probe images. Then the Nevzorov‐measured ice water contents (IWCs) at maximum diameter Dmax < 4000 µm are used as the best estimation to determine a new mass‐dimensional relationship. Finally, the newly derived mass‐dimensional relationship (a = 0.00365, b = 2.1) has been applied to a full spectrum of particle size distributions (PSDs, 120–30,000 µm) constructed from both 2DC and High‐Volume Precipitation Spectrometer measurements to calculate the best‐estimated IWCs of DCSs during MC3E. The averages of the total number concentrations (Nt), median mass diameter (Dm), maximum diameter (Dmax), and IWC from six selected cases are 0.035 cm−3, 1666 µm, 8841 µm, and 0.45 g m−3, respectively. The gamma‐type‐size distributions are then generated matching the observed PSDs (120–30,000 µm), and the fitted gamma parameters are compared with the observed PSDs through multimoment assessments including first moment (Dm), third moment (IWC), and sixth moment (equivalent radar reflectivity, Ze). For application of observed PSDs to the remote sensing community, a series of empirical relationships between fitted parameters and Ze values has been derived, and the bullet rosette ice crystal backscattering relationship has been suggested for ground‐based remote sensing.

Alpha-Particle-Based Icing Detector for Aircraft

This paper introduces a new type of icing detector for aircraft applications. Unlike the well-known icing detectors that are based on optics, the new detector uses α particles. An α-particle source is attached to the wing of the aircraft, and a detector that mainly depends on a MOSFET transistor is placed a few centimeters away from the source. As the α particles strike the detector, they deposit their positive charges on the gate of the MOSFET (n-channel), and the transistor turns ON. If, however, a layer of ice builds up on the wing and prevents the α particles from reaching the detector, the MOSFET shuts OFF. The new detector is more reliable than optics-based detectors because it is an integral part of the wing and hence cannot miss the formation of ice.

Tau neutrino and antineutrino cross sections

Tau neutrino and antineutrino interactions with nucleons in large underground or under ice detectors will be important signals of astrophysical and atmospheric sources of neutrinos. We present here a theoretical update of the deep inelastic scattering contribution to the tau neutrino and antineutrino charged current cross sections with isoscalar nucleon targets and proton targets for incident neutrinos and antineutrinos in the energy range from 10 GeV to 10 TeV. Next-to-leading order quantum chromodynamic corrections, target mass corrections and heavy quark effects are included. Uncertainties in the cross section associated with the structure functions a low momentum transfers, the input parton distribution functions, scale dependence and flavor number scheme are discussed.

Calibration and Use of Goodrich Model 0871FA Ice Detectors in Icing Wind Tunnels

A simple, new, triple-calibration scheme is developed for Goodrich (formerly Rosemount) model 0871FA ice detectors. The analog output voltage is equated not only to the usual liquid water concentration, but to accurately computed ice mass-and-depth accretion rates on the sensitive element of the detector. The three different calibration constants vary from detector to detector, but are related through invariant equations that are probe-independent. Thus, the relations can serve as universal calibration equations for any 0871FA detector. The method is demonstrated for three detectors in the steady-state conditions of an icing wind tunnel. Other observed characteristics of 0871FAs are described to help users understand the behavior of these detectors during operation

Signatures of cosmic tau neutrinos

The importance and signatures of cosmic tau (anti)neutrinos have been studied for upward- and downward-going ${\ensuremath{\mu}}^{\ensuremath{-}}+{\ensuremath{\mu}}^{+}$ and hadronic shower event rates relevant for present and future underground water or ice detectors, utilizing the unique and reliable ultrasmall-$x$ predictions of the dynamical (radiative) parton model. The upward-going ${\ensuremath{\mu}}^{\ensuremath{-}}+{\ensuremath{\mu}}^{+}$ event rates calculated just from cosmic ${\ensuremath{\nu}}_{\ensuremath{\mu}}+{\overline{\ensuremath{\nu}}}_{\ensuremath{\mu}}$ fluxes are sizably enhanced by taking into account cosmic ${\ensuremath{\nu}}_{\ensuremath{\tau}}+{\overline{\ensuremath{\nu}}}_{\ensuremath{\tau}}$ fluxes and their associated ${\ensuremath{\tau}}^{\ensuremath{-}}+{\ensuremath{\tau}}^{+}$ fluxes as well. The coupled transport equations for the upward-going ${\stackrel{(\ensuremath{-})}{\ensuremath{\nu}}}_{\ensuremath{\tau}}$ flux traversing the Earth imply an enhancement of the attenuated and regenerated ${\stackrel{(\ensuremath{-})}{\ensuremath{\nu}}}_{\ensuremath{\tau}}$ flux typically around ${10}^{4}--{10}^{5}\text{ }\text{ }\mathrm{GeV}$ with respect to the initial cosmic flux. This enhancement turns out to be smaller than obtained so far, in particular, for flatter initial cosmic fluxes behaving like ${E}_{\ensuremath{\nu}}^{\ensuremath{-}1}$. Downward-going ${\ensuremath{\mu}}^{\ensuremath{-}}+{\ensuremath{\mu}}^{+}$ events and, in particular, the background-free and unique hadronic ``double bang'' and ``lollipop'' events allow one to test downward-going cosmic ${\ensuremath{\nu}}_{\ensuremath{\tau}}+{\overline{\ensuremath{\nu}}}_{\ensuremath{\tau}}$ fluxes up to about ${10}^{9}\text{ }\text{ }\mathrm{GeV}$.

Assessing Cloud-Phase Conditions

Abstract In situ microphysics measurements made during the First and Third Canadian Freezing Drizzle Experiments (CFDE I and III, respectively) have been used to assess the relative responses to ice and liquid hydrometeors for several common instruments. These included the Rosemount icing detector, 2D-C monoscale and 2D-C grayscale probes, forward-scattering spectrometer probes (FSSP) on three measurement ranges, Nevzorov liquid water content (LWC) and total water content probes, and King LWC probes. The Nevzorov LWC and King LWC probes responded to between 5% and 30% of the ice water content, with an average response of approximately 20%. The average FSSP measurements of droplet spectra were dominated by ice particles for sizes greater than 35 μm, independent of the measurement range used, when the ice-crystal concentrations exceeded approximately 1 L−1. In contrast, the FSSP measurements of the droplet spectra less than 30 μm appeared free of ice-crystal contamination, independent of the ice-crystal con...

Assessing the Rosemount Icing Detector with In Situ Measurements

Abstract In situ measurements of microphysics conditions, obtained during 38 research flights into winter storms, have been used to characterize the performance of a Rosemount Icing Detector (RID). Characteristics of the RID were determined under a wide range of cloud environments, which included icing conditions within mixed phase, freezing rain, and freezing drizzle environments. Cloud conditions observed included temperatures between 0° and −29°C and liquid water contents (LWCs) up to 0.7 g m−3. The detection threshold for LWC was found to be 0.007 ± 0.010 g m−3 for the RID operated at an air speed of 97 ± 10 m s−1, which agrees well with theoretical predictions. A signal level of 0 ± 2 mV s−1 accounted for 99.6% of the measurements in clear air and 98.5% of the measurements in glaciated clouds, when the data were averaged over 30-s intervals. No significant response to glaciated clouds was found during any of the research flights, implying that the instrument can be used to segregate glaciated and mix...

Thermodynamics of Icing Cylinder for Measurements of Liquid Water Content in Supercooled Clouds

Abstract The Rosemount Icing Detector (RICE) has been used extensively over the last three decades for aircraft measurements of the rate of ice riming in supercooled liquid and mixed clouds. Because of difficulties related to calibration and postprocessing, the RICE probe was mainly used as an indicator of the presence of supercooled liquid water. The accuracy of the RICE probe for measurements of supercooled liquid water content is studied here. The theory of ice accretion on an unheated cylinder is applied to the RICE probe. A steady-state heat balance on the surface of a riming cylinder is considered in detail. It is shown that the threshold sensitivity of the RICE probe is limited by the rate of sublimation of ice and it may exceed 0.01 g m−3 at airspeed 200 m s−1. The rate of ice sublimation limits the use of the RICE probe for measurements of low liquid water contents in clouds. The maximum possible measured liquid water content is restricted by the Ludlam limit. A new calibration technique of the R...

Use and calibration of Rosemount ice detectors for meteorological research

Vibrating probe ice detectors made by Rosemount Inc., are used by many researchers for measuring atmospheric icing rates and cloud liquid water contents. The vibration frequency of the probe decreases as ice accretes on it, until the probe is deiced at a factory-set frequency. Rosemount ice detectors are favored because they are readily available, easy to install and simple to operate. They are designed to be used as warning systems for incipient aircraft and antenna icing, and not as precisely calibrated scientific instruments. Calibration cannot be user adjusted, but it can be measured and must be periodically checked if the ice detector is to be used in scientific studies. We briefly describe three models of Rosemount ice detectors that CRREL has used. Methods for collecting and processing the data from these ice detectors are described and evaluated. Procedures developed at CRREL for calibrating Rosemount detectors against a rotating multicylinder in natural icing conditions are presented. Results of calibrations of two model 872B12 Rosemount ice detectors with the rotating multicylinder are presented and discussed. Use of the ice detector record to calculate cloud liquid water content is described.

Wind tunnel evaluation of a rime metering device using a magnetostrictive sensor

A ground-based rime-meter developed by Hydro-Quebec was evaluated in 1992 in the icing tunnel at Université du Québec à Chicoutimi (UQAC) and this instrument is presently used in a network of stations monitoring rime and other iced precipitations in the province of Quebec (Canada). The rimemeter uses, as a sensing element, the probe of the Rosemount icing detector model 871A regulated by an improved programmable controller. The purpose of the evaluation was to characterize the frequency response of the rime-meter mounted with various probes in order to determine their dynamic sensitivity and accuracy under a variety of operating and icing conditions apt to occur in field. The tunnel investigation showed the high sensitivity of the probe to meter ice accumulation. Therefore, it appears feasible under dry conditions, with appropriate calibration, to use this ice sensor as a device for determining the liquid water content. However, its operation in freezing rain near 0°C requires further investigation in the laboratory and in the field.

Comments on “Laboratory and Wind Tunnel Evaluations of the Rosemount Icing Detector”

Comments on “Laboratory and Wind Tunnel Evaluations of the Rosemount Icing Detector”

Cable rime accretion measurements on a Laurentian mountain

Rime is an important cause of damage to structures in northern Quebec, Canada, and a major concern about the reliability of power transmission lines. An atmospheric icing test line was set up at Mt. Valin (altitude 902 m), near Chicoutimi, to measure icing rates on stranded cables. Two cables, the first one 96.5 m (316.5 ft) in span and the second one 32.6 m (106.9 ft), were used to investigate transmission line icing by comparing icing, for a complete winter, on two stranded cables, 35 mm (1.38 in.) in diameter for the first cable and 8 mm (0.315 in.) for the second. Measurements taken during the 1986–1987 winter season are analyzed. Ice accretion and shedding are correlated with ice detector alarms and wind velocity respectively. The icing intensity, considered to be proportional to the number of icing alarms per unit time, is strongly correlated with the cable icing rate. A significant correlation is also verified between the wind velocity and the ice shedding. Results of this investigation indicate that wind velocity and icing detector alarm rate are important variables to predict total ice mass on cables exposed to winter in-cloud icing. With more similar data, the implementation of an empirical icing model to estimate cable icing in mountain ranges will become possible. Key words: transmission line icing, rime accretion, ice shedding.