scholarly journals COMPARISON OF THE MEASUREMENT RESULTS OF LARGE SCALE FAÇADE FIRE TESTS USING IR THERMOGRAPHY AND THERMOCOUPLES

Author(s):  
Bojan Milovanović ◽  
Ivana Banjad Pečur

<p>In this paper the effectiveness of using a high temperature range, microbolometer infrared (IR) camera for the study of large scale façade fire tests will be investigated. The long-wave microbolometer camera has the ability to measure temperatures but the smoke and the flames itself influence the measurement results. This is due to the absorption of the infrared radiation by both smoke and flames while at the same time they emit radiation due to their high temperatures. The purpose of this study is to demonstrate the usefulness of an IR camera when studying large scale façade fire tests. The problems are difficulties in verification how representative measurements are and consequently it is not clear and sure if conditions for reliable measurements are really fulfilled. The measurement results acquired by the IR camera will be compared to the measurement results acquired by the thermocouples 1 mm, 3 mm in diameter and plate thermometers.</p>

Water ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 3171
Author(s):  
Liangliang Guo ◽  
Zihong Wang ◽  
Yanjun Zhang ◽  
Zhichao Wang ◽  
Haiyang Jiang

In order to study the mechanism of hydraulic fracturing in enhanced geothermal systems, we analyzed the influence of high temperatures and embedded fractures on the initiation and propagation of hydraulic fractures using a laboratory test and numerical simulation. The analysis was conducted via large-scale true triaxial hydraulic fracturing tests with acoustic emission monitoring. Moreover, we discussed and established the elastic-plastic criterion of hydraulic fracturing initiation. The corresponding fracturing procedure was designed and embedded into the FLAC3D software. Then, a numerical simulation was conducted and compared with the laboratory test to verify the accuracy of the fracturing procedure. The influence of high temperatures on hydraulic fracturing presented the following features. First, multi-fractures were created, especially in the near-well region. Second, fracturing pressure, extension pressure, and fracture flow resistance became larger than those at room temperature. 3D acoustic fracturing emission results indicated that the influence of the spatial distribution pattern of embedded fractures on hydraulic fracturing direction was larger than that of triaxial stress. Furthermore, the fracturing and extension pressures decreased with the increase of embedded fracture density. For hydraulic fracturing in a high temperature reservoir, a plastic zone was generated near the borehole, and this zone increased as the injection pressure increased until the well wall failed.


Nanomaterials ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 119
Author(s):  
Enzo Bertuit ◽  
Sophie Neveu ◽  
Ali Abou-Hassan

One of the most versatile routes for the elaboration of nanomaterials in materials science, including the synthesis of magnetic iron oxide nanoclusters, is the high-temperature polyol process. However, despite its versatility, this process still lacks reproducibility and scale-up, in addition to the low yield obtained in final materials. In this work, we demonstrate a home-made multiparametric continuous flow millifluidic system that can operate at high temperatures (up to 400 °C). After optimization, we validate its potential for the production of nanomaterials using the polyol route at 220 °C by elaborating ferrite iron oxide nanoclusters called nanoflowers (CoFe2O4, Fe3O4, MnFe2O4) with well-controlled nanostructure and composition, which are highly demanded due to their physical properties. Moreover, we demonstrate that by using such a continuous process, the chemical yield and reproducibility of the nanoflower synthesis are strongly improved as well as the possibility to produce these nanomaterials on a large scale with quantities up to 45 g per day.


2003 ◽  
Vol 762 ◽  
Author(s):  
A. Gordijn ◽  
J.K. Rath ◽  
R.E.I. Schropp

AbstractDue to the high temperatures used for high deposition rate microcrystalline (μc-Si:H) and polycrystalline silicon, there is a need for compact and temperature-stable doped layers. In this study we report on films grown by the layer-by-layer method (LbL) using VHF PECVD. Growth of an amorphous silicon layer is alternated by a hydrogen plasma treatment. In LbL, the surface reactions are separated time-wise from the nucleation in the bulk. We observed that it is possible to incorporate dopant atoms in the layer, without disturbing the nucleation. Even at high substrate temperatures (up to 400°C) doped layers can be made microcrystalline. At these temperatures, in the continuous wave case, crystallinity is hindered, which is generally attributed to the out-diffusion of hydrogen from the surface and the presence of impurities (dopants).We observe that the parameter window for the treatment time for p-layers is smaller compared to n-layers. Moreover we observe that for high temperatures, the nucleation of p-layers is more adversely affected than for n-layers. Thin, doped layers have been structurally, optically and electrically characterized. The best n-layer made at 400°C, with a thickness of only 31 nm, had an activation energy of 0.056 eV and a dark conductivity of 2.7 S/cm, while the best p-layer made at 350°C, with a thickness of 29 nm, had an activation energy of 0.11 V and a dark conductivity of 0.1 S/cm. The suitability of these high temperature n-layers has been demonstrated in an n-i-p microcrystalline silicon solar cell with an unoptimized μc-Si:H i-layer deposited at 250°C and without buffer. The Voc of the cell is 0.48 V and the fill factor is 70 %.


2018 ◽  
Author(s):  
Matthias May ◽  
Kira Rehfeld

Greenhouse gas emissions must be cut to limit global warming to 1.5-2C above preindustrial levels. Yet the rate of decarbonisation is currently too low to achieve this. Policy-relevant scenarios therefore rely on the permanent removal of CO<sub>2</sub> from the atmosphere. However, none of the envisaged technologies has demonstrated scalability to the decarbonization targets for the year 2050. In this analysis, we show that artificial photosynthesis for CO<sub>2</sub> reduction may deliver an efficient large-scale carbon sink. This technology is mainly developed towards solar fuels and its potential for negative emissions has been largely overlooked. With high efficiency and low sensitivity to high temperature and illumination conditions, it could, if developed towards a mature technology, present a viable approach to fill the gap in the negative emissions budget.<br>


2018 ◽  
Author(s):  
Matthias May ◽  
Kira Rehfeld

Greenhouse gas emissions must be cut to limit global warming to 1.5-2C above preindustrial levels. Yet the rate of decarbonisation is currently too low to achieve this. Policy-relevant scenarios therefore rely on the permanent removal of CO<sub>2</sub> from the atmosphere. However, none of the envisaged technologies has demonstrated scalability to the decarbonization targets for the year 2050. In this analysis, we show that artificial photosynthesis for CO<sub>2</sub> reduction may deliver an efficient large-scale carbon sink. This technology is mainly developed towards solar fuels and its potential for negative emissions has been largely overlooked. With high efficiency and low sensitivity to high temperature and illumination conditions, it could, if developed towards a mature technology, present a viable approach to fill the gap in the negative emissions budget.<br>


Alloy Digest ◽  
1995 ◽  
Vol 44 (3) ◽  

Abstract NICROFER 5520 Co is a nickel-chromium-cobalt-molybdenum alloy with excellent strength and creep properties up to high temperatures. Due to its balanced chemical composition the alloy shows outstanding resistance to high temperature corrosion in the form of oxidation and carburization. This datasheet provides information on composition, physical properties, elasticity, and tensile properties. It also includes information on high temperature performance as well as forming, heat treating, machining, and joining. Filing Code: Ni-480. Producer or source: VDM Technologies Corporation.


Alloy Digest ◽  
1994 ◽  
Vol 43 (7) ◽  

Abstract Carlson Alloy C601 is characterized by high tensile, yield and creep-rupture strengths for high temperature service. The alloy is not embrittled by extended exposure to high temperatures and has excellent resistance to stress-corrosion cracking, to carburizing, nitriding and sulfur containing environments. This datasheet provides information on composition, physical properties, elasticity, and tensile properties as well as creep. It also includes information on forming, heat treating, machining, and joining. Filing Code: Ni-458. Producer or source: G.O. Carlson Inc.


Alloy Digest ◽  
2005 ◽  
Vol 54 (11) ◽  

Abstract Incotherm TD is a thermocouple-sheathing alloy with elements of silicon and rare earths to enhance oxidation resistance at high temperatures. This datasheet provides information on composition, physical properties, and tensile properties as well as deformation. It also includes information on high temperature performance and corrosion resistance as well as forming. Filing Code: Ni-628. Producer or source: Special Metals Corporation.


Alloy Digest ◽  
1954 ◽  
Vol 3 (12) ◽  

Abstract HASTELLOY Alloy X is a nickel-chromium-iron-molybdenum alloy recommended for high-temperature applications. It has outstanding oxidation resistance at high temperatures under most operating conditions, and good high-temperature strength. This datasheet provides information on composition, physical properties, and tensile properties as well as creep. It also includes information on forming, heat treating, and machining. Filing Code: Ni-14. Producer or source: Haynes Stellite Company.


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