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1
Content available Thermodynamic Description of Ternary Fe-B-X Systems. Part 9: Fe-B-Cu
Miettinen Jyrki, Visuri Ville-Valtteri, Fabritius Timo
Archives of Metallurgy and Materials
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2021
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Vol. 66, iss. 1
297--304
EN
Thermodynamic descriptions of the ternary Fe-B-Cu system and its binary sub-system B-Cu aredeveloped in the context of a new Fe-B-X (X = Cr, Cu, Mn, Mo, Ni, Si, Ti, V, C) database. The thermodynamic parameters of the other binary sub-systems (Fe-B and Fe-Cu) are taken from earlier assessments. Experimental thermodynamic and phase equilibrium data available in the literature have been used for the optimization of the Fe-B-Cu and B-Cu systems’ thermodynamic parameters. The solution phases are described using a substitutional solution model and the compounds (two borides of the Fe-B system) are treated as stoichiometric phases. A good agreement was obtained between the calculated and the experimental thermodynamic and phase equilibrium data.
2
Content available Thermodynamic Description of Ternary Fe-B-X Systems. Part 7: Fe-B-C
Miettinen J., Visuri V.-V., Fabritius T., Vassilev G.
Archives of Metallurgy and Materials
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2020
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Vol. 65, iss. 2
923--933
EN
Thermodynamic description of the Fe-B-C system in its iron-rich corner is developed in the context of a new Fe-B-X (X = Cr, Ni, Mn, Si, Ti, V, C) database. The thermodynamic parameters of the binary sub-systems, Fe-B, Fe-C and B-C, are taken from earlier assessments modifying the B-C description. The parameters of the Fe-B-C system are optimized in this study using experimental thermodynamic and phase equilibrium data from the literature. Liquid, beta-rhombo-B and graphite phases are described using the substitutional solution model, while the ferrite (bcc), the austenite (fcc), the cementite (M3C) and the M23C6 phases are described with the sublattice model and the borides, Fe2B, FeB and B4C, are treated as stoichiometric phases. A good correlation was obtained between the calculated and the experimental thermodynamic and phase equilibrium data. The description is recommended to be used at the composition region of wt% C + wt% B < 15 and at temperatures below 2700°C.
3
Content available Impact of Ti and Fe on the Microstructure and Properties of Copper and Copper Alloys
Piękoś M., Garbacz-Klempka A., Kozana J., Żak P. L.
Archives of Foundry Engineering
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2020
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Vol. 20, iss. 4
83--90
EN
The paper discusses issues related to the technology of melting and processing of copper alloys. An assessment was made of the impact of titanium and iron introduced in the form of pre-alloy - Ti73Fe master alloy on the microstructure and selected properties of pure copper and copper-silicon alloy. There are known examples of the use of titanium and iron additive to the copper alloy. Titanium as an additive introduced to copper alloys to improve their properties is sometimes also applicable. In the first stage of the study, a series of experimental castings were conducted with variable content of Ti73Fe master alloy entering copper in quantities of 5 %, 15 %, 25 % in relation to the mass of the metal charge. In the second stage, a silicon additive was introduced into copper in the amount of about 4 % by weight and 0.5 % and 1 % respectively of the initial Ti73Fe alloy. Thermodynamic phase parameters were modelled using CALPHAD method and Thermo-Calc software, thus obtaining the crystallization characteristics of the test alloys and the percentage of structural components at ambient temperature. Experiments confirmed the validity of the use of Ti73Fe master alloy as an additive. The pre-alloy used showed a favourable performance, both in terms of addition solubility and in the area of improvement of strength properties. Changes were achieved in the microstructure, mainly within the grain, but also in the developed dendrites of the solid solution. Changes occur with the introduction of titanium with iron into copper as well as to two-component silicon bronze.
4
Content available Thermodynamic Description of Ternary Fe-B-X Systems. Part 4: Fe-B-V
Miettinen J., Visuri V.-V., Fabritius T., Milcheva N., Vassilev G.
Archives of Metallurgy and Materials
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2019
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Vol. 64, iss. 2
451--456
EN
Thermodynamic descriptions of the ternary Fe-B-V system and its binary sub-system B-V, are developed using experimental thermodynamic and phase equilibrium data from the literature. The thermodynamic parameters of the other binaries, Fe-V and Fe-B, are taken from earlier assessments slightly modifying the Fe-V description. The work is in the context of a new Fe-B-X (X = Cr, Ni, Mn, V, Si, Ti, C) database. The solution phases are described using substitutional solution model. The borides are treated as stoichiometric or semistoichiometric phases and described with two-sublattice models.
5
Content available Investigation into the effect of bore/stroke ratio on a single cylinder two stroke opposed piston engin
Alqahtani A. M., Wyszynski M. L., Mazuro P.
Journal of KONES
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2016
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Vol. 23, No. 2
9--16
EN
Opposed-piston (OP) engine’s promising fuel efficiency has attracted the interest of automotive industry in the recent years. The opposed-piston two-stroke (OP2S) engine technology heightens this fuel efficiency benefit and offers advances in structure, power density and thermal efficiency whilst sustaining its lower cost and weight. Today thermodynamic modelling remains an indispensable and cost effective route in the development and optimisation of internal combustion engines (ICEs). To achieve this goal, the OP2S engine is simulated and validated against experimental results in AVL Boost™, which is hailed as one of the most reliable and advanced engine simulation tools. Detailed analyses of the piston dynamics, heat release, scavenging and heat transfers are highlighted in discrete sections of this paper. Having compared distinct heat release models, the Wiebe 2-Zone model emerged efficacious in replicating the heat release characteristics of the PAMAR™ engine. In comparing the numerical and experimental results, the simulation revealed minimal differences in peak pressure, peak temperature and maximum pressure raise rate, under ±2.5% differences for indicated power, IMEP, indicated thermal efficiency (ITE) and ISFC. Subsequently, confidence taken from the validated numerical model is then deployed to investigate the effect of stroke-to-bore (S/B) ratio on OP2S performance. Three combinations of S/B ratios (0.5, 1.25, and 1.69) with identical swept volume are analysed in this study. Utilisation of the validated model ensured the standardisation of intake, exhaust and the combustion systems in order to isolate the effects of S/B ratio. Results indicate that heat losses decrease with increasing S/B ratio because of the reduced surface area-to-volume in the cylinder. Consequently, an improvement in ITE and mechanical efficiency is observed with reduced ISFC for higher S/B ratios. A tendency of upsurge in combustion efficiency is also evident for higher S/B ratio due to reduced heat transfer near minimum volume of the combustion chamber.
6
Content available Monazite Th-U-total Pb geochronology and P-T thermodynamic modelling in a revision of the HP-HT metamorphic record in granulites from Stary Gierałtów (NE Orlica-Śnieżnik Dome, SW Poland)
Budzyń B., Jastrzębski M., Kozub-Budzyń G. A., Konečný P.
Geological Quarterly
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2015
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Vol. 59, No. 4
700--717
EN
Thermodynamic modelling and monazite Th-U-total Pb dating via electron microprobe were used to improve the pressure, temperature and timing constraints of the HP-HT metamorphic record in granulites from Stary Gierałtów (NE Orlica-Śnieżnik Dome (OSD), SW Poland). The thermodynamic calculations constrained the P-T conditions to 20-22 kbar and ca. 920ºC in the felsic to intermediate granulites and 20-22 kbar and ca. 970ºC in the mafic granulite. These conditions are considered to closely represent the peak temperatures experienced by these rocks. In the intermediate granulite, the matrix monazite and monazite inclusions in garnet and allanite yielded an age of 349±2.5 Ma. An HP-HT metamorphic event with temperature conditions exceeding 900ºC, which are greater than the closure temperatures of most geochronometers, must have disturbed and completely reset the isotopic systems, including the Th-U-Pb system in the monazite. Consequently, this resetting prevented us from constraining the age of potential earlier metamorphic events or the igneous protolith. The 349±2.5 Ma age reflects the timing of the late-stage HP-HT event and cooling below 900ºC related to the initial exhumation of the granulites. A comparison of the new P-T-t constraints with previous data from the NE Orlica-Śnieżnik Dome indicates that the activation of the channels that exhumed the HP rocks to mid-crustal depths most likely initiated at ca. 350 Ma, and all the metamorphic rocks in the OSD likely shared a common Variscan evolution after ca. 340 Ma.
7
Content available Thermodynamic Description of Ternary Fe-B-X Systems. Part 3: Fe-B-Mn
Miettinen J., Lilova K., Vassilev G.
Archives of Metallurgy and Materials
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2014
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Vol. 59, iss. 4
1481--1485
EN
A thermodynamic optimization of the ternary Fe-B-Mn system is presented. The thermodynamic parameters of the binary sub-systems, Fe-Mn, Fe-B and B-Mn, are taken from earlier assessments slightly modifying the B-Mn system description. The thermodynamic parameters of the Fe-B-Mn system are optimized in this study using literature experimental thermodynamic and phase equilibrium data. The solution phases of the system are described using the substitutional solution model and the borides are treated as stoichiometric or semi-stoichiometric phases of the (A,B)pCq type described with the two-sublattice models.
PL
Przedstawiono termodynamiczny opis trójskładnikowego układu Fe-B-Mn. Parametry termodynamiczne dwuskładnikowych stopów Fe-Mn, Fe-B i B-Mn zostały zaczerpnięte z wcześniejszych opracowań, przy tym opis układu B-Mn został nieznacznie zmodyfikowany. Parametry termodynamiczne dla układu Fe-B-Mn zostały zoptymalizowane w tej pracy w oparciu o eksperymentalne równowagi fazowe i dane termodynamiczne zaczerpnięte z literatury. Roztwory stałe w układzie Fe-B-Mn opisano przy użyciu modelu roztworu substytucyjnego, a borki traktowane sa jako fazy stechiometryczne lub półstechiometryczne typu (A,B)pCq opisane przy użyciu modelu dwu podsieci.
8
Content available Thermodynamic Description Of Ternary Fe-B-X Systems. Part 2: Fe-B-Ni
Miettinen J., Vassilev G.
Archives of Metallurgy and Materials
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2014
|
Vol. 59, iss. 2
609--614
PL
Opis termodynamiczny trójskładnikowych układów Fe-B-X. Część 2: Fe-B-Ni
9
Content available Thermodynamic Description of Ternary Fe-B-X Systems. Part 1: Fe-B-Cr
Miettinen J., Vassilev G.
Archives of Metallurgy and Materials
|
2014
|
Vol. 59, iss. 2
601--607
EN
A thermodynamic description of the Fe-B-Cr system is developed in the context of a new Fe-B-X (X = Cr, Ni, Mn, Si, Ti, V, C) database. The thermodynamic parameters of the binary sub-systems, Fe-B, Fe-Cr and B-Cr, are taken from earlier assessments slightly modifying the Fe-B and B-Cr descriptions, and those of the ternary system are optimized in this study using experimental thermodynamic and phase equilibrium data from the literature. The solution phases are described using substitutional solution model. The borides are treated as stoichiometric or semi-stoichiometric phases and described with two-sublattice models.
PL
Przedstawiono termodynamiczny opis trójskładnikowego układu Fe-B-Cr w kontekście bazy danych dla układów Fe-B-X (X = Cr, Ni, Mn, Si, Ti, V, C). Parametry termodynamiczne dwuskładnikowych stopów Fe-Mn, Fe-B i Mn-B zostały są zaczerpnięte z wcześniejszych opracowań, przy tym opisy Fe-B i B-Cr zostały nieznacznie zmodyfikowane. Parametry dla układu Fe-Mn-B zostały zoptymalizowane w tej pracy w oparciu o eksperymentalne równowagi fazowe i dane termodynamiczne zaczerpnięte z literatury. Roztwory stałe opisano przy użyciu modelu roztworu substytucyjnego, a borki traktowane są jako fazy stechiometryczne lub półstechiometryczne opisane przy użyciu modelu dwu podsieci.
10
Content available Migration forms of chemical elements in shallow groundwater in Lithuania
Jurevicius A., Diliunas J., Jagminas E., Bajorinas V.
Polish Geological Institute Special Papers
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2005
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Vol. 18
39-44
EN
The migration forms of basic (Ca, Mg, Na, K) and polyvalent (Fe, Mn) chemical elements, heavy metals (Cd, Cu, Ni, Pb, Zn), and water saturation with minerals under natural and polluted conditions in shallow groundwater of Lithuania were calculated using a computer program WATEQ4F. Change of metals migration forms with increase of their concentration and alkalinity of environment has been well described by logarithmic functions, which can also be used for the forecasting. The migration forms of chemical compounds enable to identify the pollution sources and intensity of their influence.
PL
Wykorzystując program komputerowy WATEQ4F, określono możliwe formy migracji pierwiastków chemicznych o stałej wartościowości (Ca, Mg, Na i K) i o różnych wartościowościach (Fe, Mn) oraz metali ciężkich (Cd, Cu, Ni, Pb i Zn) w czystych i zanieczyszczonych płytkich wodach podziemnych Litwy. Zmiany mobilnych form metali wraz ze wzrostem ich koncentracji i zasadowości środowiska dobrze opisują funkcje logarytmiczne, wykorzystywane również do prognoz pogody. Mobilne formy związków chemicznych umożliwiają identyfikację źródeł zanieczyszczenia oraz intensywność ich wpływu na środowisko.
11
Content available remote Wydzielanie faz topologicznie zwarcie wypełnionych w niklowych stopach żarowytrzymałych
Paduch J., Kuziak R.
Archiwum Technologii Maszyn i Automatyzacji
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2001
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Vol. 21, Nr 1
179-188
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