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PIECHOTA Piotr SYNOWIEC Piotr ANDRUSZKIEWICZ Artur W?DRYCHOWICZ Wies?aw 《热科学学报(英文版)》2018,27(5):413-420
The article is an attempt to compile the results of CFD liquid flow simulation through pipeline section containing hydraulic elbow with the results of ultrasonic flow measurements. To carry out the measurements behind the flow disturbing element (hydraulic elbow), an ultrasonic flowmeter with applied head set in accordance with the Z-type system was used. For comparative purposes, a flow simulation for 3 different turbulence models (k-epsilon, SST and SSG) was performed. It was found that with a proper ultrasonic flowmeter heads configurations, it is possible to measure the flow rate disturbed by the hydraulic elbow at any distance from the source of the disturbance. It has to use appropriate correction factor that can be determined by knowing the flow velocity profile equation. Based on comparison of CFD simulation results with experimental data, the accuracy/ purposefulness of using individual turbulence models in the case of discussed hydraulic installation was evaluated. 相似文献
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J. Piechota P. Byszewski R. Jablo sk K. Antonova 《Fullerenes, Nanotubes and Carbon Nanostructures》1996,4(3):491-507
The electronic structure of C60 molecules with carbon substituted by other elements such as boron or nitrogen has been calculated for molecules in the singlet state with even number of electrons. Therefore, in the case of boron and nitrogen substituents, calculations have been performed for ionized molecules. The results obtained from our density functional calculations prove than in the C60-x-yBxNy molecules both HOMO and LUMO levels are split due to the lower symmetry of the molecule Influence of deformation of C60 molecules on electronic states, which is interesting because fullerenes may undergo deformation in solvate crystals, is also shown These C59B and C59N, as well as C58BN molecules are of special interest because samples containing such species can be prepared The Electron Spin Resonance (ESR) in those samples differs from the results obtained in pure C60 samples, it consists of several lines which are very sensitive to the temperature. 相似文献
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Bartłomiej Igliński Roman Buczkowski Wojciech Kujawski Marcin Cichosz Grzegorz Piechota 《Renewable & Sustainable Energy Reviews》2012,16(5):2545-2557
This paper presents the current state of geothermal energy production in Poland and its future development prospects. At present, there are four geothermal heating plants in Poland. In addition, warm water is used in seven spa towns in balneology as well as in seven thermal swimming pools for recreational purposes. There has recently been an increase in the number of installed heat pumps in Poland – reaching 10,000 in 2010. In the near future the development of geothermics in Poland is forecast to continue. The first power and heat geothermal plant is being built in Uniejów whilst in more than ten other towns special swimming pool complexes using geothermal warm water are being built or designed. In the coming years heat pumps will be installed in living and office buildings as well as in public use buildings (mostly in newly built ones). Moreover, in Poland it is planned to use heat pumps in order to recover waste heat from factories and power plants. 相似文献
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A. Nabiałek V. V. Chabanenko V. F. Rusakov S. Vasiliev N. N. Kabdin H. Szymczak S. Piechota B. N. Kodess S. A. Kononogov 《Journal of Low Temperature Physics》2005,139(1):239-246
No Heading Transverse and longitudinal magnetostriction of a large polycrystalline slab of Nb3Al superconductor was investigated by the strain gauge technique. At 4.2 K and in an external magnetic field of several Tesla the vertical width of transverse magnetostriction hysteresis loop was found to be of an order of 10–4. In a wide range of temperatures and external magnetic fields we observed the phenomenon of giant jumps of both transverse and longitudinal magnetostriction caused by thermomagnetic avalanches. The shapes of the magnetostriction hysteresis loops are also influenced by the phenomenon of the second maximum of the critical current density, called as a peak or fishtail effect. Experimental results can be understood in the framework of the model of the magnetostriction induced by pinning forces.PACS numbers: 74.70.Ad, 75.80.+q 相似文献
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Igliński Bartłomiej Piechota Grzegorz Kiełkowska Urszula Kujawski Wojciech Pietrzak Michał Bernard Skrzatek Mateusz 《Clean Technologies and Environmental Policy》2023,25(1):281-298
Clean Technologies and Environmental Policy - The following article explains the current condition of the photovoltaics sector both in Poland and worldwide. Recently, a rapid development of solar... 相似文献