Shield Panels Research Articles

Polyurethane reinforced with micro/nano waste slag as a shielding panel for photons (experimental and theoretical study)

This study not only provides an innovative technique for producing rigid polyurethane foam (RPUF) composites, but it also offers a way to reuse metallurgical solid waste. Rigid polyurethane (RPUF) composite samples have been prepared with different proportions of iron slag as additives, with a range of 0–25% mass by weight. The process of grinding iron slag microparticles into iron slag nanoparticles powder was accomplished with the use of a high-energy ball mill. The synthesized samples have been characterized using Fourier Transform Infrared Spectroscopy, and Scanning Electron Microscope. Then, their radiation shielding properties were measured by using A hyper-pure germanium detector using point sources 241Am, 133 BA, 152 EU, 137Cs, and 60Co, with an energy range of 0.059–1.408 MeV. Then using Fluka simulation code to validate the results in the energy range of photon energies of 0.0001–100 MeV. The linear attenuation coefficient, mass attenuation coefficient, mean free path, half-value layer and tenth-value layer, were calculated to determine the radiation shielding characteristics of the composite samples. The calculated values are in good agreement with the calculated values. The results of this study showed that the gamma-ray and neutron attenuation parameters of the studied polyurethane composite samples have improved. Moreover, the effect of iron slag not only increases the gamma-ray attenuation shielding properties but also enhances compressive strength and the thermal stability. Which encourages us to use polyurethane iron-slag composite foam in sandwich panel manufacturing as walls to provide protection from radiation and also heat insulation.

Investigation on the pressure drop characteristics of ITER thermal shield cooling pipes

This paper presents the experimental results of the pressure drop through the cooling pipes of the ITER Thermal Shield (TS) panels. High pressure and room temperature nitrogen gas is selected for the experiment, which is equivalent operating condition with the 80 K helium gas from fluid mechanics point of view. Flow rate is set by a mass flow controller and pressure difference between the inlet and the outlet of the cooling pipe is measured by a differential pressure gauge. The experimental set-up is open loop type, which is connected to high pressure gas bottle. Flexible corrugated pipes are used to connect the TS cooling pipes with the measurement system line. The effect of the corrugated pipe is evaluated separately and excluded from the measurement results of the TS pipes. Test results of several TS panels are shown in this paper and are compared with the calculation using existing friction factor correlation and local loss coefficient of the pipe bends. The limitation of the calculation is discussed considering the hydrodynamic developing flow in the pipe routing.

Elaboration of X-ray shielding of highly barite-loaded polyester concrete: structure, mechanical properties, and MCNP simulation

Various research has been done in manufacturing and designing different types of radiation shielding. In this study, lead-free polymer composite panels with new special formulations have been prepared and characterized to prevent radiation leakage in medical facilities at the diagnostic energy range (60 – 120 keV). Polyester resin is used as a binder along with large amounts of mineral barium sulfate (barite) aggregate (more than 70 % by weight). SEM micrographs showed a homogeneous distribution of barite particles. Then the effects of adding barite on the physical, mechanical, and thermal properties of composite panels were investigated. The results showed that increasing the percentage of barite powder in the formulation, with the high wetting capability of polyester resin, improved physical and mechanical properties. The composite panel containing 80 wt% of barite had the highest tensile and flexure strength. Also the thermal stability of the composite panel containing 90 wt% of barite was 40 °C to 50 °C more than other samples. The samples' mass attenuation coefficient (μm) was calculated experimentally and theoretically using MCNP-5 simulation software and the XCOM program. Experimental and calculated results have been compared and were found to be in reasonable agreement. In general, with increasing barite content, the composite shielding panel became denser and μ increased while HVL and TVL values decreased. In addition, the studied shields were superior to lead by virtue of their non-toxic nature and will be a radiation shielding solution in making wall panels.

Development and test of a confining and recycling sprayer for viticulture

Abstract In the tropical and subtropical viticulture, it is notorious that the occurrence of a favorable microclimate leads to a high incidence of plant pathologies. This affects the productivity and longevity of the vines. In many cases, the incidence of rainfall and high relative humidity, during most of the vine cycle, leads to a large number of interventions for phytosanitary control. The continuous, and not always correct use of pesticides, causes their residues to be deposited in the environment, leading to changes in the ecosystem, accumulation in non-target organisms and the water, with the potential to cause serious problems for man and his habitat. That matter has highlighted the need for more accurate technologies for the spraying of active ingredients in crops. Therefore, the investigation of more appropriate procedures and equipment is justified, for greater protection of the workers and the microenvironment, as well as for higher efficiency in the application of active ingredients. Based on the above, a prototype of a confining and recycling sprayer was developed and tested at the Centro de Engenharia e Automacao (CEA) of the Instituto Agronomico (IAC), in Jundiai (Sao Paulo state), between 2017 and 2019 growing seasons. Spray outlets were arranged in vertical ducts and accommodated in two shield panels. The prototype was arranged as a straddle, floating over-the-row. Part of the liquid sprayed, not adhered to the leaves, was collected at the bottom of the shield panels and pumped back into a reservoir for recirculation. Tests were carried out to evaluate the performance as for uniformity of adaxial leaf coverage in the vineyard, using image analysis. The results showed that the mechanical configuration used made it possible to promote significant recovery of the liquid and a satisfactory percentage of leaf coverage.

DEVELOPMENT OF MAGNETICALLY SHIELDED ROOM COMPRISED OF COBALT-BASED AMORPHOUS ALLOY

Paying attention to cobalt-based amorphous alloy as magnetic shielding material to replace permalloy, the authors attempted to modify materials suitable for magnetic shielding by heat treatment. Furthermore, magnetic shaking technique was applied. As a result, incremental magnetic permeability could be increased to about 59.5 times that of permalloy. Next, the magnetically shielded room using cobalt-based amorphous alloy was developed. It was confirmed that shielding performance was greatly improved as a result of fabrication of magnetic shield modules, coupling them to fabricate magnetic shield panels, and adding them as magnetic shielding layers to an established magnetically shielded room.

Shielding performances of the designed hybrid laminates impacted by hypervelocity flyer

With increasing threat of man-made debris in outer space, a shielding panel designed for spacecraft or satellite should withstand hypervelocity impact of debris, with speed up to 9.0km/s. In this study, shielding performances of 2024 aluminum alloy panel, carbon fiber reinforced polymer composite (CFRP) panel and their hybrid laminates with different stacking configurations were investigated by ballistic tests of the materials impacted by Mylar flyer at 9.0km/s. The results are supposed to guide the design of shielding laminate panel. It was found that the stacking combination of CFRP and aluminum alloy significantly reduced the peak shock pressure induced by hypervelocity impact, and the increase of the layer number enhanced the shielding performance of the hybrid laminate. The five-layered aluminum alloy/CFRP laminates resisted the impact of the flyer without perforation. Furthermore, the extent of the damage of an impacted laminate was related to the velocity profile on its free surface. The planar plate impact testing employing a Doppler laser velocity interferometer is a feasible approach to quantitatively evaluate the shielding performance of structural material.

Experimental Investigation of Aluminum Foam Lined Suppressive Shield Containment Vessels

Manufacture, transport, and storage of dangerous goods, especially energetic materials, in Canada and around the world pose serious challenges to explosives regulators and inspectors. Currently siting of manufacturing and storage facilities are in accordance with quantity-distance principles designed to mitigate effects of accidental explosions. The land requirements to satisfy these principles are imposing financial burdens on the explosives sector. This paper presents an experimental program designed to investigate the effectiveness of suppressive shield containers in reducing the blast pressure outside of the container while eliminating fragments thus reducing the distance requirement for the stored amount of explosives. Several suppressive shield panels including aluminium foam-lined panels were tested to study their effect on blast pressure and impulse. In addition computational fluid dynamics techniques were used to study suppressive shields effects on blast environment. The results show reduction of the incident peak blast pressure by 60% and the incident impulse by 58%. The aluminium foam-lined suppressive shield panels attenuated the peak incident pressure and impulse by 80%.

Aluminum Foam-Lined Suppressive Shields for Safe Transport of Explosives

The manufacture, transportation, and storage of explosives in Canada and around the world pose serious challenges to explosives regulators and inspectors tasked with ensuring the safety of nearby populations. Explosives are routinely transported through, and manufacturing and storage facilities are often located close to, populated areas and traffic routes. This proximity increases the risk of severe casualties and infrastructure damage if there is an accidental or deliberate explosion. Even though an explosion is unlikely, the consequences can be severe. Several accidents that have involved explosives are discussed in the literature. These accidents highlight the devastation likely to result from an explosion and underscore the importance of finding cost-effective solutions to mitigate the effects on the population and infrastructure. This paper presents a research program designed to investigate the effectiveness of suppressive shield containers in reducing the blast pressure outside the container and eliminating fragment hazards from an explosion. Several types of suppressive shield panels, including panels lined with aluminum foam, were tested in a blast chamber. The results show reduced peak blast pressure outside the container by as much as 60% and in the incident impulse by about 58%. When the suppressive shield was lined with aluminum foam, a further reduction in peak incident pressure (up to 80%) was achieved.

Switchable Faraday Shielding With Application to Reducing the Pain of Internal Cardiac Defibrillation While Permitting External Defibrillation

Switchable Faraday shielding is desirable in situations where electric field shielding is required at certain times and undesirable at other times. In this study, electrostatic finite element modeling was used to assess the effect of different shield geometries on the leakage of an internally applied field and penetration of an externally applied field. "Switching OFF" the shield by electrically disconnecting shield faces from each other was shown to significantly increase external field penetration. Applying this model to defibrillation, we looked at the effect of spacing and size of shield panels to maximize the ability to deliver an external defibrillation shock to the heart when shield panels are disconnected while providing acceptably low leakage of internal defibrillation shocks to avoid painful skeletal muscle capture when shield panels are connected. This analysis may be useful for designing internal defibrillator electrodes that preserve the efficacy of internal and external defibrillation while avoiding the significant morbidity associated with painful defibrillator shocks. Similar analysis could also guide optimizing the switchable Faraday shielding concept for other applications.

Thermal and mechanical analysis of Wendelstein 7-X thermal shield

The thermal insulation of Wendelstein 7-X cryostat consists of multi-layer insulation (MLI) and a thermal shield. The shield is cooled by helium gas flowing in pipes which are attached to the shields via copper strips or braids. The paper presents the basic thermal and mechanical layout of the thermal shield. The design is strongly influenced by the tight design space. Main mechanical loads on the shield are electromagnetic forces resulting from rapid shut down of the magnet system and the self weight. Design and calculations were performed iteratively. Copper and brass were checked in combination with different electrical isolation variants. The induced eddy currents will be reduced if the upper and the lower half shells of the cryostat are electrically isolated against each other. The cryostat shield and the port shields are made of brass. The expected heat loads on the shield were estimated. The resulting temperature distribution was then calculated for brass and copper shield panels. The average shield temperature is below 85 K and fulfills the thermal requirements.

Magnetic Noise in a Magnetically-Shielded Room due to Mechanical Vibration

Event Abstract Back to Event Magnetic Noise in a Magnetically-Shielded Room due to Mechanical Vibration Keita Yamazaki1*, Takayuki Abe1, Norio FujiMaki2, Tsutomu Murata2 and Koichiro Kobayashi3 1 Takenaka Corporation, Japan 2 National Institute of Information and Communications Technology, Japan 3 Iwate University, Japan An Active Microtremor Isolation (ACMI) system is used as the basement of a Magnetically Shielded Room (MSR) to reduce vibration. We measured vibrations of the MSR and the magnetic noises (MNs) inside the MSR to know the relationship between them under the normal condition and the condition in which artificial vibration was applied to the concrete slab (CS). Since the accelerations of ceiling outside the MSR (Arx, Arz) were reduced by the ACMI at frequencies from 1 to 100 Hz, they were considered to be caused by mechanical vibration via floor. However, the velocity of the wall (Lwx) and ceiling (Lrz), and the MNs inside the MSR were reduced by the ACMI at frequencies higher than 10 Hz, but not less than 10 Hz. Since the velocities were measured by the vibrometer placed inside the MSR, this suggests that the mechanical vibration caused the MSR to tremble with deformation at frequencies higher than 10 Hz, but without deformation at frequencies lower than 10 Hz; the former one produced MNs. The coherence functions (CFs) at frequencies from 10 to 20 Hz were high (peaking more than 0.9) between Lwx / Lrz, and MNs for ACMI-OFF. Among a few peaks of CFs, a peak at 16.7 Hz is considered to reflect mechanical resonance properties (MRPs) of the MSR, which agrees with that analyzed by a finite element analysis of structure composed by flames and shield panels When controlled footsteps were applied on the CS, MNs and the accelerations of ceiling outside the MSR differed at frequencies higher than 10 Hz, where the peaks at 45 and 52 Hz are considered to reflect the higher mode of MRP of the MSR. The CFs at frequencies from 10 to 20 Hz, and 30 to 70 Hz, were high (peaking more than 0.9) between Arx and MNs for ACMI-OFF. In summary, the present results show that MNs due to vibrations depend on fundamental mode (10-20 Hz) of MRP under the normal condition, while both on fundamental and higher modes (10-20 Hz, and 30-70 Hz) of MRP when artificial vibration was applied to the CS. This work was supported by the Japan Society for the Promotion of Science for Grant-in-Aid for Exploratory Research 20651043. Conference: Biomag 2010 - 17th International Conference on Biomagnetism , Dubrovnik, Croatia, 28 Mar - 1 Apr, 2010. Presentation Type: Poster Presentation Topic: Instrumentation and Multi-modal Integrations: MEG, Low-field MRI,EEG, fMRI,TMS,NIRS Citation: Yamazaki K, Abe T, FujiMaki N, Murata T and Kobayashi K (2010). Magnetic Noise in a Magnetically-Shielded Room due to Mechanical Vibration. Front. Neurosci. Conference Abstract: Biomag 2010 - 17th International Conference on Biomagnetism . doi: 10.3389/conf.fnins.2010.06.00423 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 09 Apr 2010; Published Online: 09 Apr 2010. * Correspondence: Keita Yamazaki, Takenaka Corporation, Inzai, Japan, keita-y@sam.hi-ho.ne.jp Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Keita Yamazaki Takayuki Abe Norio FujiMaki Tsutomu Murata Koichiro Kobayashi Google Keita Yamazaki Takayuki Abe Norio FujiMaki Tsutomu Murata Koichiro Kobayashi Google Scholar Keita Yamazaki Takayuki Abe Norio FujiMaki Tsutomu Murata Koichiro Kobayashi PubMed Keita Yamazaki Takayuki Abe Norio FujiMaki Tsutomu Murata Koichiro Kobayashi Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Numerical and experimental investigations for safer transportation of dangerous goods

Transportation of dangerous goods (DG) represents an important portion of the overall transport of freight in the world. Ground transport (excluding pipelines) moves approximately 21% to 31% of the total tonnage of DG in Canada. Accidents involving DG might occur at any time, at any location along transport routes or within storage areas and they not only affect people and the environment but also have a great impact on the national economy. This paper presents the details of experimental investigation studying the blast attenuation capability of suppressive shield panels (SSP). Moreover, the performance of one type out of four designed suppressive shield panels (SSPs) using a numerical approach to verify an experimental study. The technology can be used for the storage, processing and transport of explosive materials, or can also be applied to protecting attractive targets and infrastructure that is deemed vulnerable to explosive attacks, including those attacks accompanied by the threat of fragment bombs. Various configurations of commercially-available steel angles were assembled as SSPs and were evaluated for their capability to attenuate blast pressure from detonating Pentolite charges. Results obtained from the experimental tests of 0.5 kg charges indicated that the SSPs attenuate the blast pressure to values in the range of 40% to 60%. The results of this research can be extended to include the design and construction of SSPs for transportation of DG by sea as well. Effectively, this can include the strengthening of current standard containers.

Improving the Safety of Transportation of Dangerous Goods

The transportation of dangerous goods (DG) represents an important portion of the overall freight transport worldwide. Ground transport (excluding pipelines) moves approximately 21% to 31% of the total tonnage of DG in Canada. Accidents involving DG might occur at any time at any location along transport routes or within storage areas, and not only do they have an effect on people and the environment, but also they can have a great effect on the national economy. This paper presents the details of an experimental investigation studying the blast attenuation capability of suppressive shield panels (SSPs). Suppressive shield technology can be used for the storage, processing, and transport of explosive materials and can also be applied to protecting attractive targets and infrastructure deemed vulnerable to explosive attacks. Various configurations of commercially available steel angles were assembled as SSPs and evaluated for their ability to attenuate blast pressure from detonating Pentolite charges. Results obtained from the tests with 0.5-kg charges indicated that the SSPs attenuate the blast pressure to values in the range of 43% to 60%. The results of this research can be extended to include the design and construction of SSPs for transportation of DG by sea as well. Effectively, this can include the strengthening of current standard containers.

Use of focused pulse-echo ultrasonics for non-destructive inspection of thick carbon-carbon structures

The reinforced carbon-carbon (RCC) heat shield components on the Space Shuttle's wings must withstand harsh atmospheric re-entry environments where the wing leading edge can reach temperatures of 3000°F (about 1650°C). Potential damage includes impact damage, micro cracks, oxidation in the silicon carbide-to-carbon-carbon layers, and interlaminar disbands. The thick, carbon-carbon and silicon-carbide layers in the heat shield panels are difficult to inspect and existing techniques were deemed to be inadequate. Since accumulated damage in these structures can lead to catastrophic failure of the Shuttle's heat protection system, it became imperative for NASA to develop quickly an acceptable health monitoring programme. NASA selected a multi-method approach for inspecting the wing leading edge which includes eddy current, thermography, and ultrasonics. Sandia Labs produced the in-situ ultrasonic pitch-catch inspection method. Optimum combinations of custom ultrasonic probes and data analysis were merged into the overall inspection method needed to properly survey the heat shield panels. Comprehensive validation tests revealed that the ultrasonic pitch-catch inspection system is capable of reliably finding flaws of 0.25 diameter or less in the heat shields. The inspection system is now in use at NASA to complete 'Return-to-Flight' certification inspections prior to each Shuttle launch.

High temperature strength and thermal stability for melt growth composite

Melt growth composites (MGCs) have a microstructure, in which continuous networks of single-crystal Al 2O 3 phases and single-crystal oxide compounds (YAG (Y 3Al 5O 12), GAP (GdAlO 3)) interpenetrate without grain boundaries. Therefore, the MGCs have excellent high-temperature strength characteristics, creep resistance, superior oxidation resistance and thermal stability in the air atmosphere at very high temperature. To achieve ultra-high thermal efficiency and low NO x emission for gas turbine systems, we produced turbine nozzle vanes that does not require cooling and heat shield panels for combustor liners. The thermal stability and mechanical properties of these parts have been studied. The high-temperature strength characteristics and the thermal stability of components were also no changes after heat treatment for 500 h at 1700 °C in an air atmosphere. The favorable properties of melt growth composite have been discussed for possible application in gas turbine system.

Improved longitudinal magnetic shielding by an amorphous FeSi steel composite panel

An improved magnetic shielding using the magnetic shaking technique with a planar mesh coil is applied to develop a composite shielding panel of Fe-based amorphous sheet and Si steel sheet. The mesh coil, sandwiched by the two ferromagnetic materials, makes a two-dimensional shaking field that enhances magnetic shielding. The composite panel annealed without field shows exceedingly high longitudinal shielding effectiveness. Fine and circular magnetic domains of amorphous Fe-based ribbons contribute to the magnetic shielding effectiveness for alternating fields at high frequencies.

電磁鋼・鉄基非晶質合金複合材料の磁気シールド特性

An improved magnetic shielding method using the magnetic shaking technique with a planar mesh coil was used to develop a composite shielding panel consisting of Fe-based amorphous sheets and Si-steel sheets. The mesh coil, sandwiched by the two ferromagnetic materials, creates a two-dimensional shaking field that enhances magnetic shielding. The composite panel, annealed without the application of a field, shows an exceedingly high shielding effectiveness of 470. The fine and circular magnetic domains of Fe-amorphous ribbons annealed without the application of a field contribute to the magnetic shielding effectiveness of alternating fields at high frequencies.

An improved mesh shaking coil and its application to a magnetic shielding panel

An improved structure for a mesh shaking coil with finite area is presented by which shielding performance of ferromagnetic shielding is enhanced while suppressing unwanted leakage of the shaking field. A surrounding conductor is added in series to a finite mesh coil in order to cancel the edge effect which deteriorates the multipole distribution of the shaking field. Cancellation of the edge effect is confirmed by experiment and calculation. The improved mesh coil is applied to develop a magnetic shielding panel with a magnetic sheet/coil/magnetic sheet sandwich structure. The shielding factor of a 20-cm/sup 2/ shielding panel of 6.5% Si-Fe steel was enhanced about three times to 152 by magnetic shaking using the mesh shaking coil.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Wind pressure load on an industrial building

Deflector shield panels in front of the top-lit-louver were designed for the roof of a low-rise industrial building to improve natural ventilation. Both wind pressure loads acting on the deflector shields for structural calculations, and pressure data in the vicinity of the window rows for ventilation calculations were needed. A wind tunnel test, modelling suburbian surroundings by turbulent boundary layer flow and simulating several wind directions and building group configurations, was carried out on models of the buildings scaled at 1:200. Mean, RMS and peak pressure coefficients were determined and presented for the structural and ventilation design.

Vibration and flutter analysis of reusable surface insulation panels

A study has been conducted of the aeroelastic behavior of heat shield panels for the thermal protection system of the space shuttle. Questions of structural and aerodynamic modeling are considered along with the analysis of a single isotropic tile and an isotropic main substructure. Representative flutter results are presented, taking into account a rigid and a flexible metallic substructure.