Radiation Intensity Measurements Research Articles

An improved passive solar still integrated with pulsating heat pipes and phase change materials

This paper presents a theoretical analysis of a novel solar still system, which was previously explored through experimental studies. The experimental results demonstrate that integrating phase change material (PCM) to store latent heat from vapor condensed on sidewalls during sunlight exposure, along with the use of pulsating heat pipes (PHPs) to recover this stored energy after sunset, and cooling the condenser sidewalls with PCM, significantly boosts the system’s efficiency from 23.7 % to 48.5 %. These innovative features, applied for the first time in a single-stage passive solar still, are thoroughly examined using a groundbreaking mathematical model. This model is the first to uniquely account for heat transfer and condensation on sidewalls and to accurately simulate the function of pulsating heat pipes (PHPs) within a passive solar still setup. By incorporating measured radiation intensity and ambient temperatures, the model applies an exhaustive energy balance, utilizing heat transfer correlations and resistances for precise temperature predictions of each component. This detailed analysis highlights the system’s innovative aspects and identifies areas for further refinement, shedding light on potential improvements and the system’s limitations. The results show a water production of 6.7931 kg/m2 and an efficiency of 52.2 %, with a discrepancy of 7.8 % compared to experimental findings. Notably, 37.6 % of the total freshwater production is derived from sidewall condensation, significantly reducing heat loss by capturing latent heat. Additionally, by reallocating 9.3 % of stored energy, the PHPs maintain the saline water temperature 6.2 degrees higher at night, thereby sustaining elevated production rates.

ON THE ISSUE OF COMPREHENSIVE ASSESSMENT OF THE IMPACT OF THERMAL RADIATION AT WORKPLACES, TAKING INTO ACCOUNT AIR POLLUTION

Problem statement. The research demonstrates that existing methods for determining the distribution of thermal radiation intensity using nomograms and formulas contain significant errors. This is due to the adoption of a number of simplifications regarding numerous interdependent parameters, including the temperature inside furnaces, the size of openings and shafts, etc. As a result, there is a need for measurements of thermal radiation intensity at distances of 5−10 meters and beyond. The purpose of the article. The objective of the article is to propose a concept for a new experimental methodology to investigate the intensity of radiation exposure to workers at their workplaces. Simultaneously, in order to address the issues of thermal protection for workers, actual measurement data of thermal radiation levels are necessary for each workstation under real working conditions within the workspace. Conclusion. It is important to characterize the composition of the gas environment, as its impurities can distort the distribution of radiant energy through interference and diffraction effects, which need to be considered for microclimate optimization. The presence of dust particles complicates the straight-line heat transfer through scattering and scintillation of rays, requiring further improvement of models. Turbulence, impurities, and atmospheric heterogeneity are important factors that need to be further investigated and taken into account in heat transfer process modeling. Scintillation affects the quality of radiation transmission, necessitating further study of this phenomenon. Local atmospheric composition peculiarities require the development of models that consider these variations. The obtained experimental data will contribute to improving the accuracy of modeling and enhancing working conditions. Further refinement of measurement techniques is necessary for obtaining reliable information.

How to Rapidly Evaluate Uranium Adsorption Capacity Using Only a Portable Geiger Counter?

AbstractThe development of the nuclear industry has stimulated research in uranium extraction from seawater (UES) by adsorption. However, in practical applications, it's hard to equip various ion concentration measurement instruments for real‐time characterizing uranium adsorption capacity. Given the radioactive property of uranium, if only a Geiger counter is possessed, how it can be utilized to rapidly evaluate uranium adsorption in the adsorbent? This study proposes the Geiger‐Uranium‐Distance model, which establishes correlations among Geiger counter readings, uranium adsorption capacity, and distance, thereby offering a viable approach. While maintaining a constant radius for the adsorbent stack point, during the laboratory phase, the average molecular mass (MA) and the kGg(z) values of the original adsorbent are determined. In practical applications, the surrounding radiation background GE (µSv h−1) is detected. Subsequently, the Geiger counter is vertically positioned above the stacked point of adsorbent after uranium adsorption. Utilizing the measured radiation intensity value G (µSv h−1), and employing the equation , the uranium adsorption capacity Qe can be obtained.

Solar Radiation Intensity Imputation in Pyranometer of Automatic Weather Station Based on Long Short Term Memory

Automatic Weather Station (AWS) experienced problems in the form of component damage and communication system failure, resulting in incomplete parameter data. Component damage also occurs in pyranometers. Decreased pyranometer performance results in deviations, uncertainty in measuring solar radiation intensity, and data gaps. Data imputation is one solution to minimize measurement deviations and the occurrence of missing AWS pyranometer data. This research aims to design and analyze the accuracy performance of the multisite AWS pyranometer solar radiation intensity data imputation model when a data gap occurs. This research attempts to utilize the spatio-temporal relationship of multisite AWS solar radiation intensity in the imputation model. Long-Short Term Memory (LSTM) algorithm is used as an estimator in the multisite AWS pyranometer network. Data imputation modeling stage includes data collection, data pre-processing, creating missing data scenarios, LSTM design and model testing. Overall, LSTM-based imputation model has ability of filling gap data on AWS Cikancung pyranometer with maximum missing sequence of 12 hours. Imputation model has MAPE 1.76% - 5.26% for missing duration 30 minutes-12 hours. It still it meet WMO requirement for solar radiation intensity measurement with MAPE<8%.

APPLICATION OF ULTRAVIOLET LED SYSTEMS IN THE GRAIN PROCESSING AND COMPOUND FEED INDUSTRIES

The materials of the article outline the features of the use of ultraviolet LED systems in industry, and propose a solution for their use in the grain processing and compound feed industry. Ultraviolet light (UV) is a well-researched and widely used means of decontamination and disinfection of surfaces, air, water, and food. Usually, far ultraviolet radiation (or ultraviolet C, UVC) with a wavelength of 254 nm is used, which corresponds to the peak absorption of wave energy by the DNA of a living cell. There is a mathematical mechanism for calculating the parameters of radiation in relation to its effect on microorganisms: a curve describing the microbial death depending on the increase in the radiation dose received by the bacteria and formulae for the relationship between the three main parameters (dose, radiation flux and exposure duration). Ultraviolet lamps (tubes) are commonly used, on the basis of which a large number of emitters have been developed for different needs. There are also emitters for grain and feed disinfection in use, but only outside of industrial production lines. Ultraviolet irradiation is not used directly on manufacturing lines so far. However, it can be used to reduce the microbial burden of a feed or food product prior to packaging the finished product. For this purpose, ultraviolet light-emitting diodes (LEDs) available on the world market today can be used. However, their use faces difficulties: ultraviolet LEDs emit wavelengths longer than lamps (at about 275 nm or more), which requires an increase in the duration of irradiation, which is undesirable for industrial processing of products directly on the line. However, the small size of the UVC LEDs will allow them to be installed in grain processing and feed mills inside equipment (magnetic separators, gravity feeders, etc.) with appropriate protection against damage by moving material. In addition, suspended emitters of any configuration can be placed above belt conveyors that move material at a certain speed. This approach will require certain measures to control the efficiency of irradiation (requires microbiological studies) and to protect personnel from the harmful effects of ultraviolet rays (means of personal and collective protection, measurement of radiation intensity).

Characterization of the vertical evolution of urban nocturnal boundary layer by UAV measurements: Insights into relations to cloud radiative effect

The complex structure of the nocturnal boundary layer (NBL) and its impact on air pollution remain poorly understood. In this study, we present in-situ nocturnal flight measurements onboard an unmanned aerial vehicle (UAV) during the wintertime of 2022 at an urban site in Hefei, China. Besides, co-located measurements of radiation intensity and total amount of cloud were conducted. The vertical distribution of temperature, particle number concentration, and relative humidity were obtained to study the structure of NBL and the key factors driving the evolution of the NBL. A multi-layer inversion boundary layer was observed during haze and fog episodes, which affects the vertical diffusion of particles near the surface and leads to a vertical gradient of particle number concentrations. The particle size distribution demonstrates a drastic vertical variation over different sections of the nocturnal boundary layer: homogeneously mixed in the SBL and the RL layer, sharply reduced in the IL. It is found that the temperature and particle number concentration differences between near-surface and at 500 m are highly related to variations of the radiation intensity and the amount of cloud. The decreased cloud cover enhances the surface cooling, creating a shallow NBL with multiple inversion layers, which reinforces the suppression of vertical diffusions and consequently promotes the accumulation of aerosols within the NBL. This reveals an important mechanism for the impact of NBL evolution modulated by cloud radiative effect on the formation of urban haze.

Measurement performance evaluation and noise compensation for a Fourier transform infrared–based pyrometer

The Fourier transform infrared (FTIR) spectrometer is widely used for spectrum analysis and radiation intensity measurement. In this work, a pyrometer with the temperature measurement range of 800°C to 1200°C is developed based on the FTIR spectrometer, and the calibration of the instrument coefficients using a standard radiation source is performed. On this basis, the readout noise and shot noise in the spectral signal are analyzed, and a detailed quantitative evaluation of the influences of two kinds of noise on the temperature measurement accuracy is also carried out in this work. Experimental results show that the temperature deviation caused by the two kinds of noise is less than 1°C when the wavelength is within the range of 2.0 to 5.4 μm. However, when the wavelength is greater than 5.4 μm, the maximum temperature deviation caused by the readout noise and shot noise can reach about 12°C and 18°C, respectively. In view of this, a Kalman filter method is introduced in this work to reduce temperature fluctuations caused by these noises, where the maximum fluctuation can be reduced from 83.9°C to 6.1°C with this filter method. These experimental results can provide a valuable guidance for the general-purpose calibration and assessment of the FTIR-based pyrometer.

Determination of the Electron Temperature of Shock-Heated Air from the Measured Radiation Intensities

Determination of the Electron Temperature of Shock-Heated Air from the Measured Radiation Intensities

Understanding of the Experimental Concept of Radiation Absorption of Radioactive Materials

<span lang="EN-US">In this article, we discuss the experimental absorption of radioactive light radiation on various materials using Geiger Muller. Under certain conditions, Geiger Muller can be used to determine the absorption coefficient of a material. The radioactive rays observed in this experiment are gamma rays. Gamma rays are radioactive rays that have no charge so they cannot be deflected by magnetic or electric fields and have the greatest penetrating power. We made several important results on experimental studies of the absorption of gamma radiation passing through matter. Our results relate to the trend of the unexpected, measured intensity of radiation versus the thickness of the absorber, which confuses students and cannot be explained by many laboratory assistants. Finally, we believe that a distribution function is an effective tool for examining the contribution of the build-up factor in the Geiger Muller calculation of the measured radiation intensity.</span>

Edge Effects on Simultaneous Reconstructions of Flame Temperature and Soot Volume Fraction Profiles by a CCD Camera.

In this paper, the influence of the edge effect on the simultaneous reconstruction of axisymmetric flame temperature and soot volume fraction profiles by a single CCD camera was investigated in detail. The reconstruction accuracy of the flame temperature profile and soot volume fraction was insensitive to the measurement error of the coefficient matrix. When the signal to ratio (SNR) of the measurement system for both the radiation intensity and coefficient matrix was as low as 46 dB, the reconstruction accuracy for both temperature and soot volume fraction was acceptable and was more influenced by the radiation intensity measurement error. The reconstruction of the flame temperature and soot volume fraction was greatly influenced by the edge effect. When the flame edge with weak radiation signals was ignored during the reconstruction, the relative reconstruction error for the temperature and soot volume fraction increased from the flame center to the edge, and reached an unacceptable value at the reconstruction boundary, especially for the soot volume fraction. The flame image boundary could be chosen as the unified reconstruction boundary to reconstruct the two-dimensional distribution of the temperature and soot volume fraction with satisfactory accuracy. The low soot volume fraction could influence the reconstruction accuracy for both the temperature and soot concentration in non-sooting regions. Moreover, there was no obvious regularity between the reconstruction accuracy of the temperature and soot volume fraction and the extension of the reconstruction boundary.

Effect of lead nanoparticles on the radiation shielding characteristics of carbon fiber/epoxy composites

Materials with shielding capabilities against gamma radiation are important for nowadays applications in order to alleviate radiation damage. This study investigates the shielding characteristics of carbon fiber/epoxy composites incorporating lead nanoparticles (Pb-NP) of variable weight fractions. The composites in this experimental study are prepared using the hand-layup vacuum bagging process at room temperature. Mass attenuation coefficients are calculated for composites with variable Pb-NP weight fractions based on radiation intensity measurements taken using NaI (Tl) scintillation detector. The results show that adding small fractions of lead nanoparticles to the matrix phase of the composite material leads to improving its shielding properties, including their linear attenuation coefficient, mass attenuation coefficient and the Half-Value Layer (HVL). The results also show that mass attenuation coefficients of composite material with added Pb-NPs are higher than those of pure lead. For validation purposes, the experimental results are compared to computational results obtained using MCNP5 code for the same weight fractions of Pb-NPs. The two sets of results were found to be in good agreement with a maximum relative error of ∼16%.

Effect of Dilution on Forced Ignition of Jet-A/Air Mixtures

Consistent ignition in environments where combustion products are present is critical for the safety and reliability of some propulsion applications. Prior research has shown that residual can reduce the probability of forced ignition of mixtures by decreasing the concentration of H radicals. However, the applicability of these observations to larger hydrocarbon fuels, such as jet-A, is not known. Ignition probabilities and volumetric kernel growth rates for vaporized jet-A/air/diluent mixtures were determined from radiation intensity measurements collected using an FLIR SC6700 infrared camera. Measurements of ignition probability of jet-A/air mixtures showed no appreciable reduction in ignition probability for mixtures with similar and . Mixtures diluted with showed no statistical change in average growth rates compared to undiluted and diluted mixtures. One-dimensional reacting flow simulations were conducted to help identify why no apparent chemical sensitivity to was observed for the jet-A/air mixtures, in contrast to results reported for . A greater concentration of H radicals was predicted for jet-A/air mixtures when compared to mixtures, even when is present. Further analysis showed that different reaction pathways exist for jet-A when compared to and that these reaction pathways are affected differently in the presence of residual .

A Method for Estimating On-Field Photovoltaics System Efficiency Using Thermal Imaging and Weather Instrument Data and an Unmanned Aerial Vehicle

A new approach is proposed for estimating the power efficiency of an on-field solar photovoltaics (PV) system using data from thermal imaging and weather instruments obtained using an unmanned aerial vehicle (UAV). This method is specifically designed for the non-intrusive detection of the performance of the PV system in a large-scale solar power plant that could be efficient, manpower saving, operationally safe and comprehensive. In this study, a drone instrumented with a radiometer, a thermometer and an anemometer flew at a height of 1.5 m with a maximum lateral flight speed of 3.6 m/s above the PV modules (60 cells each) with hotspots or with aging but without hotspots. The average temperatures of the PV modules were then calculated through the measured radiation intensity, ambient temperature and wind speed based on the published correlation formula. The experimental correlations were obtained by measuring over 60 aging PV modules without hot-spot damage, and the uncertainties of the estimated efficiencies fell between 2% and 5%. Through the use of 20 hot-spot damaged PV modules when the measured temperatures of the cells were in the range of 80–90 °C, it was found that based on the experimental correlationd, their power efficiencies would be lower than 40% if more than eight cells had hot spots in a PV module. By taking this simple measure, the operator can decide which PV module is damaged and should be replaced immediately. By taking such measures, one can reduce the loading effect of solar PV modules adjacent to them because of the low efficiency and high impedance caused by the damage. We believe the new approach developed in this study could be very cost-effective and time-saving for improving the efficiency of power plant operations.

Rancang Bangun Sensor Node untuk Monitoring Parameter Cuaca dan PM2.5 Menggunakan Arduino WiFi

Sensor node untuk monitoring parameter cuaca dan PM2.5 terdiri dari sensor parameter cuaca berupa suhu, kelembaban, intensitas cahaya, curah hujan, kecepatan angin dan arah angin. Selain itu terdapat parameter kualitas udara yaitu sensor PM2.5. Pengolahan dan pengiriman data dilakukan oleh Arduino Uno WiFi yang merupakan perangkat mikrokontroller yang sudah terintegrasi dengan ESP8226 yang merupakan modul untuk mengkoneksikan dengan jaringan WiFi. Data sensor dikirimkan dari Arduino ke data base server untuk selanjutnya ditampilkan pada website. Hasil pengujian masing-masing sensor dibandingkan data BMKG menunjukkan hasil kesalahan pengukuran yang kecil untuk parameter suhu dan curah hujan dengan masing-masing prosentase kesalahan sebesar 4.61% dan 9.95%. Hasil pengukuran parameter kecepatan angin memiliki kesalahan cukup besar yaitu 30.03% disebabkan oleh pengukuran kecepatan angin dilakukan pada ketinggian yang berbeda dengan sensor BMKG. Pengukuran arah angin menunjukkan frekuensi arah angin yang berbeda karena tidak dilakukan setting titik referensi yang sama dengan sensor BMKG pada saat peletakan sensor. Pengukuran PM2.5 juga menunjukkan hasil kesalahan pengukuran cukup besar yaitu 14.7% karena peletakan sensor tidak dikondisikan dengan standar seperti pada sensor BMKG sehingga sampel partikulat yang diukur tidak sama dengan sensor BMKG. Untuk pengukuran intensitas cahaya dan kelembaban masing-masing telah menunjukkan trend yang sesuai dengan kodisi lingkungan. Pengujian pengiriman data juga berjalan dengan baik karena semua data yang tersimpan di database server berada pada kolom yang benar pada data base serta menunjukkan hasil yang sama dibandingkan dengan sampel data yang dibaca sensor secara manual.

Menentukan Intensitas Radiasi UV yang Diterima Pekerja Pengelasan dengan Titik Area Mata, Siku, dan Betis

The aim of this study is to measure the UV intensity received by the welders during working time and compare the results of measured radiation intensity which is obtained with the NAB in Regulation of the Minister of Manpower No. 05 of 2018 that is 0,0008 mW/cm2. The reason for using this NAB is for compare value while welding process with the value were allowed from Regulation of the Minister of Manpower. This study has been done in some workshops using the UV Meter and focused on the welders’ eye, elbow and calf area with 10 repetitions in each area. The results for eye area were 0.0749 mW/cm2, for elbow area were 0.0843 mW/cm2and for calf area were 0.0934 mW/cm2and all the results obtained exceed the NAB. The high value is caused by the environmental conditions is open and also affected by indeterminate sunlight, the risks received the welders in watery eye and headache because of the welder are disobey in using PPE while welding process.

Improved scatter correction model for high attenuation gamma-ray tomography measurements

In this study a state-of-the-art gamma-ray tomography (GRT) unit was used to measure the solids concentration distributions of high density, high attenuation clay/water/sand slurries in a 4 in. (100 mm) diameter recirculating pipe loop. The presence of neighbouring radiation sources on the GRT results in a scattered radiation contribution to the total intensity measured at each detector. The scattered radiation decreases the signal-to-noise ratio of the measured radiation intensity and introduces error in the measured tomography data and the reconstructed tomograms (Maad et al 2008 Meas. Sci. Technol. 19 6). Because of the high attenuation of the materials being measured, the scatter contribution was a significant fraction of the total radiation measured at each detector. To correct for the scattered radiation contribution in the measurements, a test campaign was undertaken to characterize and model the scattering behaviour of the GRT at the Saskatchewan Research Council. The scattered radiation was measured experimentally from empty pipe, water filled pipe and a number of flowing clay/water/sand slurries at densities ranging from 1206 kg m−3 to 1580 kg m−3. A semi-empirical scatter correction model has been developed which allows the scattered contribution at each detector to be calculated iteratively based on the measured uncorrected attenuated radiation intensity. This article is an extension of the work presented at the 9th World Congress for Industrial Process Tomography (Spelay et al 2018 Proc. 9th World Congress Industrial Process Tomography p 14).

Effect of CO2 dilution on forced ignition and development of CH4/air ignition kernels

Reliable ignition of reactant mixtures containing combustion products is important to the function of many practical combustion devices. Prior work has considered the influence of CO2 on ignition delay times and laminar flame speeds. This work examines the effects of dilution with CO2 on forced ignition and development of ignition kernels in CH4/air mixtures. Ignition kernels were initiated by a high voltage spark discharge in CH4/air/diluent mixtures with a bulk velocity of 5 m/s and with 0.7 ≤ Φ ≤ 0.8. Ignition probabilities and kernel growth rates were determined from radiation intensity measurements collected using a Telops MS-IR FAST infrared camera. Nitrogen was used as an inert in a subset of conditions to facilitate identifying changes in chemistry associated with dilution by CO2. Chemistry effects of diluents on ignition were isolated by examining undiluted, N2 diluted, and CO2 diluted flows with equivalent adiabatic flame temperatures. Dilution with CO2 reduced the probability of ignition relative to undiluted and N2 diluted conditions with the same adiabatic flame temperature. Ignition kernels diluted with CO2 also tended to be smaller than those initiated in both undiluted and N2 diluted mixtures, with reduced growth rates.

Mobile robot for radiation mapping in indoor environment

Radiation mapping is the process of measuring radiation intensity level at distributed sampling points in a predefined region of interest (ROI). This procedure is crucial in any radiological related emergency to locate contamination hotspot(s) or in routine inspections in any radiation facilities. When workers knowingly enter a high radiation zone to perform radiation mapping, they are exposed to the risk of radiation exposure. Mobile robot is a potential solution that could eliminate the health and safety risk and subsequently improve the measurement accuracy. This paper reports implementation of mobile robot for radiation mapping by using a commercial mobile robot platform, Turtlebot2 in conjunction with Robot Operating System (ROS). Mobile robot is capable to generate physical map of the targeted environment by using Simultaneous Localization and Mapping (SLAM). Simultaneously, Geiger Muller detector is utilized to perform radiation measurement. The radiation data is directly plotted on the physical map hence the radiation intensity distribution throughout the ROI could be assessed. Functionality of the radiation mapping robot is evaluated in real-world experiments and the results will be presented in the paper.

Diagnostics of ultra-intense laser pulses using tunneling ionization

We revisit a recently proposed scheme (Ciappina et al 2019 Phys. Rev. A 99 043405) for accurate measurement of electromagnetic radiation intensities in a focus of high-power laser beams. The method is based on the observation of multiple sequential tunneling ionization of atoms and suggests determination of the peak intensity value from the appearance in the focal area ions with a certain charge number. Here we study the sensitivity of the approach to two essential factors: the focal volume effect and the tunneling ionization model chosen to calculate ionization rates. We show, on the one hand, that the results appear almost model independent for ionization of helium- and hydrogen-like ions and, on the other hand, that the focal averaging leaves the intensity-dependent features visible. Our findings are in favor to a practical implementation of the atomic diagnostics of extreme laser intensities.

Обзор и классификация методов оценки и прогнозирования солнечной радиации

Various methods used to estimate and predict solar radiation are reviewed. Ground-based solar radiation intensity measurements are not carried out everywhere, despite the fact that the need to estimate the gross (theoretical) potential of solar energy in a region arises quite often. In such cases, approximate estimates of solar energy resources are carried out using various models, the main ones of which are considered in this paper. The availability of an adequately estimated local solar energy potential is important not only for rational distribution of funds in designing, but also for predicting the output of a power plant that uses solar energy. A general classification of methods for estimating and predicting solar radiation by the type of used parameters and estimated quantities (physical and statistical models) is presented. Statistical methods include conventional empirical models, in which the monthly average daily sums of solar radiation on a horizontal surface are estimated with dividing them into 4 categories depending on the input parameters involved, and models that evaluate the sums of the solar radiation diffuse component on horizontal (decomposition models and parametric models) and inclined (isotropic and anisotropic models) receiving areas. Models based on data mining methods are also referred to statistical methods for estimating and predicting solar radiation. The suggested statistical models are based on various parameters such as sunshine duration, maximum ambient temperature, relative humidity, pressure, latitude and longitude of the locality, the day of year ordinal number, cloudiness index, average ambient temperature, altitude, average wind velocity, precipitation, etc. The results of modeling the monthly average daily amounts of total solar radiation on a horizontal surface according to the universal empirical models are evaluated and compared with the long-term average data of ground-based measurements on the territory of Kyrgyzstan and with the data from the NASA POWER database.