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Tytuł:
Uwagi na marginesach "Dzieł" sir Joshuy Reynoldsa, wyd. Edmond Malone, Londyn 1798
Annotations to Reynolds “Discourses, ed. Edmond Malone, Londyn 1798
Autorzy:
Blake, William
Jaźwierski, Jacek
Powiązania:
https://bibliotekanauki.pl/articles/706962.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Blake
Reynolds
Annotations
Uwagi
Opis:
Polish translation of Wiliam Blake's Annotations to Reynolds' Discourses
Źródło:
Rocznik Historii Sztuki; 2012, 37; 141-164
0080-3472
Pojawia się w:
Rocznik Historii Sztuki
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Uwagi na marginesach „Dzieł” sir Joshuy Reynoldsa: Williama Blake’a spor z Reynoldsem o sztukę
William Blake ’s annotations to Reynolds “Discourses ”: William Blake ’s Quarrel with Reynolds on art
Autorzy:
Jaźwierski, Jacek
Powiązania:
https://bibliotekanauki.pl/articles/707133.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Blake
Reynolds
art theory
teoria sztuki
Opis:
William Blake’s annotations to the first volume of “The Works of Sir Joshua Reynolds” prove an excellent and at the same time fascinating source of knowledge about his views on art. They depict Blake as a rebel against the established rules in English artistic life of the late 18th and early 19th centuries. The poet identifies their origin in the beliefs and artistic policies of the first President of the Royal Academy, Sir Joshua Reynolds. This article, a commentary to the translated version (in the same volume) of “Annotations”, at its core primarily attempts to highlight theoretical and artistic issues, but does not shy away from biographical, social and political topics necessary to an understanding of Blake’s artistic and personal views. Relations between the two adversaries, strained ever since Blake’s studies at the Royal Academy in the first half of the 1780s, took on a mythical character of enmity after Reynolds’ death. Blake was the first to criticize the highly regarded Seven Discourses on Art by Reynolds, where - not always fairly – he saw proof of theoretical contradictions and the decline of art. The clash between Reynolds’ aesthetic rationalism and empiricism and Blake’s mysticism precluded the possibility of agreement. All this does not mean, however, that the dispute between Blake and Reynolds was free of paradoxes and ambiguities and that his mind was completely detached from the academicism and classicism of official English art. On the contrary. This article tries to show that, like any radical rebel, Blake largely belonged to the world from which he tried to break away, that his art grew out of 18th-century categories and can best be understood as such.
Źródło:
Rocznik Historii Sztuki; 2012, 37; 129-140
0080-3472
Pojawia się w:
Rocznik Historii Sztuki
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of a cross-channel micromixer through the dynamics of tracer gradient
Autorzy:
Gonzalez, M.
Powiązania:
https://bibliotekanauki.pl/articles/281009.pdf
Data publikacji:
2016
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
Low-Reynolds number flows
mixing enhancement
micromixers
Opis:
The study aims at showing how the dynamics of tracer gradient accounts for the stirring mechanism produced by a periodically forced flow relevant to practical mixing operation. The numerical simulation uses the equations for the orientation and norm of the tracer gradient and an analytic model for velocity. To a large extent, the micromixer properties over different ranges of the Strouhal number are explained through the response of the tracer gradient orientation to the tilting of strain principal axes resulting from flow forcing. The analysis also reveals a rich picture of stirring as the Strouhal number is varied.
Źródło:
Journal of Theoretical and Applied Mechanics; 2016, 54, 4; 1257-1269
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Differences method topology of hydrodynamic pressure calculations from Reynolds equation
Autorzy:
Wierzcholski, K.
Powiązania:
https://bibliotekanauki.pl/articles/246229.pdf
Data publikacji:
2010
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
Reynolds equation
new numerical solution
urvilinear boundary conditions
Opis:
The main topic of the presented paper concerns the method of determination and calculations of the general and particular numerical solutions of modified Reynolds equation in curvilinear orthogonal coordinates for curvilinear boundary conditions for hydrodynamic pressure distributions in bearing gap. A general solution matrix was derived and determined for various orthogonal coordinates of two cooperating bearing surfaces separated by the oil existing in slide Journal bearings. From mathematical point presented method of solution of modified Reynolds equation leads this problem to resolving the partial recurrence non homogeneous, linear equation of second order with variable coefficients. As an example the numerical hydrodynamic pressure calculation for slide bearing two cylindrical surfaces limited bearing gap with various eccentricities was in this paper performed. In numerical calculations are applied the formulae and calculation algorithm derived in this paper. Moreover, presented numerical topology of calculations in this paper enables to find the optimum way of determination of pressure values for an applied difference method regarding to the stability of solutions, convergences of the obtained values with various orthogonal shapes of cooperating surfaces. An adaptation of the known numerical difference method to the various curvilinear orthogonal boundary conditions applied during the hydrodynamic pressure determination on the two various curvilinear cooperating surfaces, to be decisive after author knowledge about a new achievement consisted in presented paper.
Źródło:
Journal of KONES; 2010, 17, 4; 583-590
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Shear Stress Statistics in a Compound Channel Flow
Autorzy:
Czernuszenko, W.
Rowiński, P. M.
Powiązania:
https://bibliotekanauki.pl/articles/241044.pdf
Data publikacji:
2008
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
open channels
turbulence
measurements
Reynolds stresses
coherent structures
Opis:
The results of comprehensive measurements of three-dimensional turbulent velocities carried out in a laboratory compound channel are presented. Tests were performed in a two-stage channel with a smooth main channel bed consisting of concrete and rough floodplains and sloping banks. Instantaneous velocities were measured with the use of a three-component acoustic Doppler velocimeter. The main aim of the study is the recognition of structure of Reynolds stresses in turbulent open channel flows. Particular attention has been paid to bursting events such as ejections and sweeps. The bursting phenomenon occurs originally near the buffer layer and then shows a coherent or organized flow structure during its convection process. The probability density distributions of the turbulent velocities were measured at different distances from the bed in the main channel and also above the inclined walls. In the main channel, the lateral turbulent velocity is seen to follow the normal Gaussian distribution more closely than the remaining two components. Above the inclined walls, all distributions turned out to have greater skewness. The probability density distributions of correlations between velocity fluctuations were also calculated. These distributions have long tails and sharp peaks and fit the theoretical distributions very well. The structure of instantaneous Reynolds stresses was analyzed by a quadrant technique with an arbitrarily chosen threshold level. It has been shown that the largest contribution to turbulent stresses comes from the second quadrant (ejection) and the fourth quadrant (sweep). The basic temporal characteristics for quadrant events, like the average and maximum time for a zero hole size, have been determined in the study. Calculations of maximum duration times for all events reveal that times are greater for even quadrants than for odd quadrants.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2008, 55, 1-2; 3-27
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On general-purpose turbulence models in CFD
Autorzy:
Pozorski, J.
Powiązania:
https://bibliotekanauki.pl/articles/175545.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
computational fluid dynamics
turbulence modeling
Reynolds-averaged approaches
Opis:
The computational fluid dynamics (CFD) tools for various flow problems have become widespread nowadays, yet their use still needs attention and care. In particular, turbulence models are often a crucial part of flow computations undertaken with various software packages, either commercial, open-source or in-house. In the paper, an overview of available model categories is provided, together with some discussion of their advantages or drawbacks with respect to flow cases of interest.
Źródło:
Transactions of the Institute of Fluid-Flow Machinery; 2015, 127; 45-62
0079-3205
Pojawia się w:
Transactions of the Institute of Fluid-Flow Machinery
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Characteristic of Vertical Reynolds Shear Stress in a Patchy Heterogeneous Open Channel
Autorzy:
Olatunji, Peter Folorunso
Powiązania:
https://bibliotekanauki.pl/articles/1177793.pdf
Data publikacji:
2018
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Reynolds Stress
gravel
heterogeneous
open channel
patchy
turbulence
vegetation
Opis:
In turbulent flow, the Reynolds stress provides an understanding of the shear dispersion within the flow. Turbulence can be said to have an effect equivalent to the Reynolds shear stresses and are indicators of turbulence transport. This paper examined the characteristic of vertical Reynolds Shear stress in a patchy heterogeneous open channel using two experimental conditions for flexible and rigid vegetation interaction with gravel bed. The results show the value of vertical Reynolds stress decreases downstream along the channel section and as the distance from change in roughness increases. This is attributed to the effects of the bed roughness configuration (due to the preceding vegetated bed roughness) on the vertical Reynolds stress distribution. However, the position of maximum vertical Reynolds stress is located near bed over the vegetated zone. This provides an indication that the vegetated bed serves as the primary source of turbulence for the flow.
Źródło:
World Scientific News; 2018, 99; 1-14
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A New Star-Like SurfaceTexture for Enhanced Hydrodynamic Lubrication Performance
Autorzy:
Uddin, M. S.
Liu, Y. W.
Shankar, S.
Powiązania:
https://bibliotekanauki.pl/articles/356465.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
surface texturing
friction
film pressure
numerical modelling
Reynolds equation
Opis:
This paper presents a numerical modelling and optimization of a new ‘star-like’ geometric texture shape with an aim to improve tribological performance. Initial studies showed that the triangle effect is the most dominant in reducing the friction. Motivated with this, a ‘star-like’ texture shape consisting of a series of triangular spikes around the centre of the texture is proposed. It is hypothesised that by increasing the triangular effect on a texture shape, the converging micro-wedge effect is expected to increase, hence increasing the film pressure and reducing the friction. Using the well-known Reynolds boundary conditions, numerical modelling of surface texturing is implemented via finite difference method. Simulation results showed that the number of apex points of the new ‘star-like’ texture has a significant effect on the film pressure and the friction coefficient. A 6-pointed texture at a texture density of 0.4 is shown to be the optimum shape. The new optimum star-like texture reduces the friction coefficient by 80%, 64.39%, 19.32% and 16.14%, as compared to ellipse, chevron, triangle and circle, respectively. This indicates the potential benefit of the proposed new shape in further enhancing the hydrodynamic lubrication performance of slider bearing contacts.
Źródło:
Archives of Metallurgy and Materials; 2017, 62, 3; 1863-1869
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical modeling of heat transfer in Al2O3/H2O nanofluid flowing through a Bessel-like converging pipe
Autorzy:
Iweka, Chukwuka S.
Fadodun, Olatomide G.
Powiązania:
https://bibliotekanauki.pl/articles/1845460.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
nanofluid
Nusselt number
response surface methodology
Reynolds number
convergence
index
Opis:
This paper studies hydrodynamic and heat transfer performance of Al2O3/H2O nanofluid flowing through a Bessel-like converging pipe in laminar flow regime using the computational fluid dynamic approach. A parametric study was carried out on the effect of Reynolds number (300– 1200), convergence index (0-3) and nanoparticle concentration (0–3%) on the both hydrodynamic and thermal fields. The results showed the pressure drop profile along the axial length of the converging pipes is parabolic compared to the downward straight profile obtained in a straight pipe. Furthermore, an increase in convergence index, Reynolds number and nanoparticle concentration were found to enhance convective heat transfer performance. Also, a new empirical model was developed to estimates the average Nusselt number as a function of aforementioned variables. Finally, the result of the thermohydraulic performance evaluation criterion showed that the usage of Bessel-like converging pipes is advantageous at a low Reynolds number.
Źródło:
Archives of Thermodynamics; 2021, 42, 2; 121-153
1231-0956
2083-6023
Pojawia się w:
Archives of Thermodynamics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical modeling of heat transfer in Al2O3/H2O nanofluid flowing through a Bessel-like converging pipe
Autorzy:
Iweka, Chukwuka S.
Fadodun, Olatomide G.
Powiązania:
https://bibliotekanauki.pl/articles/1845485.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
nanofluid
nusselt number
response surface methodology
Reynolds number
convergence
index
Opis:
This paper studies hydrodynamic and heat transfer performance of Al2O3/H2O nanofluid flowing through a Bessel-like converging pipe in laminar flow regime using the computational fluid dynamic approach. A parametric study was carried out on the effect of Reynolds number (300– 1200), convergence index (0-3) and nanoparticle concentration (0–3%) on the both hydrodynamic and thermal fields. The results showed the pressure drop profile along the axial length of the converging pipes is parabolic compared to the downward straight profile obtained in a straight pipe. Furthermore, an increase in convergence index, Reynolds number and nanoparticle concentration were found to enhance convective heat transfer performance. Also, a new empirical model was developed to estimates the average Nusselt number as a function of aforementioned variables. Finally, the result of the thermohydraulic performance evaluation criterion showed that the usage of Bessel-like converging pipes is advantageous at a low Reynolds number.
Źródło:
Archives of Thermodynamics; 2021, 42, 2; 121-153
1231-0956
2083-6023
Pojawia się w:
Archives of Thermodynamics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Lattice Boltzmann method for fluid mixing: a comparison with the finite element method
Autorzy:
Egidi, N.
Misici, L.
Piergallini, R.
Tosi, F.
Powiązania:
https://bibliotekanauki.pl/articles/1955715.pdf
Data publikacji:
2004
Wydawca:
Politechnika Gdańska
Tematy:
lattice Boltzmann method
incompressible viscous fluid mixing
Reynolds number
numerical simulation
Opis:
In this article we study three-dimensional mixing of an incompressible viscous fluid subjected to the force of rotating blades in a vessel, with a low Reynolds number. The results obtained with the lattice Boltzmann method are compared with the ones previously obtained using the finite element method. All the qualitative and quantitative parameters of the two simulations agree.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2004, 8, 1; 5-15
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Long Way Down: Making Space for an Empathic Understanding of African-American Adolescents through Literature
Autorzy:
Gray, Pennie
Powiązania:
https://bibliotekanauki.pl/articles/2031287.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Wrocławski. Oficyna Wydawnicza ATUT – Wrocławskie Wydawnictwo Oświatowe
Tematy:
multicultural literature
African-American
adolescent
Long Way Down
Jason Reynolds
poetry
Opis:
There has long been a call for more diverse representation in literature for children and adolescents in the United States, for children who read multicultural literature can both see themselves reflected in the literature they read and be exposed to authors from diverse backgrounds who can serve as role models for them. One such author is Jason Reynolds, a prolific African-American author of books for adolescents. His most recent book, Long Way Down, is the poignant story of a fifteen year old African-American young man named Will who must make a life-and-death decision. While Will could be viewed as impulsive and potentially violent due to the saturation of gang-related activity in his neighborhood, Reynolds’ crafting of the text compels the reader to reconsider this assessment and instead take a more empathic stance toward Will. More specifically, the author’s compelling use of cultural compassion, poetic form, and time flexibility combine to draw the reader into a deeper understanding of the complexities of Will’s life. This compassionate treatment of the main character creates a narrative that is appealing to young African-American readers who thirst for books that reflect their lives and that unveil the challenges they face as they navigate the violence that often plagues urban life. Long Way Down also provides a meaningful and realistic counter-narrative to an all-to-widely accepted view of African-American males as dangerous and violent.
Źródło:
Filoteknos; 2020, 10; 111-125
2657-4810
Pojawia się w:
Filoteknos
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of Variable Electroconductivity and Radiation on MHD Couette Flow
Autorzy:
Ngiangia, Alalibo T.
Okechukwu, Amadi
Powiązania:
https://bibliotekanauki.pl/articles/1192671.pdf
Data publikacji:
2016
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
MHD
Electrconductivity
Prandtl number
Grashof number
Reynolds Number
Radiation
Couette flow
Opis:
A study of Couette flow in cylindrical coordinate under the influence electroconductivity and magnetic field was carried out. Approximate solution of the governing equations and its analysis show decrease in temperature as a result of increase in radiation and Prandtl number. The study also reveals that increase in grashof number, Reynolds number, Prandtl number and electroconductivity result in an increase in velocity distribution while magnetic field increase, lead to a decrease in velocity. The shear stresses of the outer and inner cylinders at the wall of the plates and the heat flux is also determined.
Źródło:
World Scientific News; 2016, 47, 2; 241-253
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical investigation for convective heat transfer of nanofluid laminar flow inside a circular pipe by applying various models
Autorzy:
Saeed, Farqad Rasheed
Al-Dulaimi, Marwah Abdulkareem
Powiązania:
https://bibliotekanauki.pl/articles/1845502.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
convective heat transfer
Reynolds number
nanofluid
single-phase flow
thermophysical properties
Opis:
The work presents a numerical investigation for the convective heat transfer of nanofluids under a laminar flow inside a straight tube. Different models applied to investigate the improvement in convective heat transfer, and Nusselt number in comparison with the experimental data. The impact of temperature dependence, temperature independence, and Brownian motion, was studied through the used models. In addition, temperature distribution and velocity field discussed through the presented models. Various concentrations of nanoparticles are used to explore the results of each equation with more precision. It was shown that achieving the solution through specific models could provide better consistency between obtained results and experimental data than the others.
Źródło:
Archives of Thermodynamics; 2021, 42, 1; 71-95
1231-0956
2083-6023
Pojawia się w:
Archives of Thermodynamics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical investigation and sensitivity analysis of entropy generation of Al2O3/H2O nanofluid in turbulent regime using response surface methodology
Autorzy:
Fadodun, Olatomide G.
Olokuntoye, Bolanle A.
Salau, Ayodeji O.
Amosun, Adebimpe A.
Powiązania:
https://bibliotekanauki.pl/articles/240104.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
entropy production
Reynolds number
response-surface-methodology
nanofluid
single-phase flow
Opis:
This work investigates the effect of Reynolds number, nanoparticle volume ratio, nanoparticle size and entrance temperature on the rate of entropy generation in Al2O3 /H2O nanofluid flowing through a pipe in the turbulent regime. The Reynolds average Navier-Stokes and energy equations were solved using the standard k-ε turbulent model and the central composite method was used for the design of experiment. Based on the number of variables and levels, the condition of 30 runs was defined and 30 simulations were run. The result of the regression model obtained showed that all the input variables and some interaction between the variables are statistically significant to the entropy production. Furthermore, the sensitivity analysis result shows that the Reynolds number, the nanoparticle volume ratio and the entrance temperature have negative sensitivity while the nanoparticle size has positive sensitivity.
Źródło:
Archives of Thermodynamics; 2020, 41, 2; 119-146
1231-0956
2083-6023
Pojawia się w:
Archives of Thermodynamics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The influence of the microgrooves on the hydrodynamic pressure distribution and load carrying capacity of the conical slide bearing
Autorzy:
Czaban, A.
Powiązania:
https://bibliotekanauki.pl/articles/246488.pdf
Data publikacji:
2012
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
conical slide bearing
pressure distribution
microgrooves
Reynolds equation
load carrying capacity
Opis:
The aim of this work is to determine the hydrodynamic pressure distribution in oil film and the load carrying capacities of conical slide micro bearings with grooved sleeves. The results for some bearings examples are presented. For the bearings taken into account, the Reynolds equation was solved by the method of Finite Differences. In the calculations, the Reynolds boundary condition was applied. The simulation was performed for the conical slide micro bearings with the groves parallel to the cone generating line. The function of lubrication gap height for the conical slide bearings with sleeves covered with microgrooves was assumed on the basis of existing papers. The results obtained for the analogous bearings without the microgrooves are also shown, therefore the influence of microgrooves on the conical slide micro bearings can be observed. On the basis of the results, one can conclude, that applying microgrooves on the bearing sleeve surface causes the increase of the value of hydrodynamic pressure and longitudinal and transverse components of the load carrying capacity of the bearing. Furthermore, the effect of the microgrooves and their impact is noticeable in graphs of hydrodynamic pressure distribution. The applied method of investigation of the impact of microgrooves on a bearing operation is simpler and less expensive than the experimental studies, however it is necessary to verify that the results obtained with this method are correct and whether in fact applying microgrooves, besides form facilitate lubrication, causes the improvement in bearing operating parameters.
Źródło:
Journal of KONES; 2012, 19, 3; 85-91
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Differential and recurrence unified reynolds equations and mega algorithm for their numerical solutions
Autorzy:
Wierzcholski, K.
Miszczak, A.
Powiązania:
https://bibliotekanauki.pl/articles/242919.pdf
Data publikacji:
2012
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
partial differential form
partial recurrence form
unified Reynolds equation
mega algorithm
Opis:
The objective of the research under the paper topic is an analytical, unified formulation of a new standardized view of general solution of hydrodynamic problem using algorithm to determine changes of the components of the velocity vector, the distributions of hydrodynamic pressure, load carrying capacity, of slide bearings with cooperating curvilinear, orthogonal surfaces that are lubricated with a various non-Newtonian lubricants. In this paper for non- Newtonian lubricants are questioning the hitherto prevailing assumptions using in hydrodynamic theory of lubrication such as constant value of lubricant viscosity and pressure in the thickness of lubricating gap i.e. in gap height direction. Finally, the non-homogeneous partial differential equation generated with variable coefficients that is the result of the various boundary conditions being imposed that are different for each problem solved is an equation that determines the distributions of hydrodynamic pressure values. This equation is to be written in the form of a unified non-homogenous partial recurrence equation with variable coefficients. The Authors foresee that a mega-algorithm will be developed for the solution of this equation in a numerical form. This equation in particular cases is an equivalent of modified Reynolds equations in the research that has been conducted so far concerning the hydrodynamic theory of lubrication.
Źródło:
Journal of KONES; 2012, 19, 4; 643-650
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Autobiografikcja. Eksperymenty z życiopisaniem od przełomu wieków po modernizm
Autobiografiction. Experimental Life-Writing from the Turn of the Century to Modernism
Autorzy:
Saunders, Max
Sobolewska, Agnieszka
Powiązania:
https://bibliotekanauki.pl/articles/1431045.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Szczeciński. Wydawnictwo Naukowe Uniwersytetu Szczecińskiego
Tematy:
Stephen Reynolds
autobiografiction
fact
fiction
life-writing
autobiografikcja
fakt
fikcja
życiopisanie
Opis:
Artykuł porusza rozległy, a przy tym zaskakująco niedoinwestowany temat związków autobiografii i fikcji w okresie między rokiem 1880 a 1930. Jego istotą jest przeformułowanie poglądów na temat relacji między modernizmem i praktykami życiopisania. W tym celu Saunders przywołuje opublikowany w roku 1906 esej Stephena Reynoldsa, autora autobiograficznej książki A Poor Man’s House, w którym pojawia się pojęcie autobiografikcji, zaskakująco podobne do pojęć ze słownika ponowoczesnego. Saunders przygląda się rozumieniu tego terminu w czasach Reynoldsa i dowodzi jego przydatności, niedającej się sprowadzić jedynie do historycznego kontekstu jego powstania.
This essay approaches the large but surprisingly under-theorized topic of the relation between autobiography and fiction, concentrating on the period between 1880 and 1930, arguing for a new account of the relation between Modernism and life-writing. It introduces and analyses a key essay from 1906 by Stephen Reynolds, author of A Poor Man’s House, which, strikingly, coins the post-modern-sounding term ‘autobiografiction’. It argues that Reynolds’ central concept sheds light on the vexed theoretical question of the relation between autobiography and fiction, and in ways that reach further than either Reynolds or the essay’s few commentators have appreciated.
Źródło:
Autobiografia Literatura Kultura Media; 2020, 15, 2; 41-65
2353-8694
2719-4361
Pojawia się w:
Autobiografia Literatura Kultura Media
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Characteristics of Laminar Flow in Pipelines of Homogenous Alum Sludge Approximated with use of the Vočadlo Model for Viscoplastic Liquids
Charakterystyka laminarnego płynięcia w rurociągach jednorodnych osadów pokoagulacyjnych aproksymowanych modelem cieczy plastyczno-lepkich Vočadli
Autorzy:
Kempiński, J.
Sozański, M. M.
Dymaczewski, Z.
Świerzko, R.
Powiązania:
https://bibliotekanauki.pl/articles/205416.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
alum sludge
rheology
hydrotransport
Reynolds number
osad pokoagulacyjny
reologia
liczba Reynoldsa
Opis:
The study presents the manners of determination of the Darcy friction factor λ for a homogenous hydromixture of alum sludge of varied hydration and temperature for the laminar flow zone. The rheological evaluation of the hydromixture as a viscoplastic body has been conducted with use of measurements of viscosity. The curves of flow were approximated with use of the generalized Vočadlo model. The Darcy friction factor λ of the pipeline was determined with use of the non-dimensional criterion λ(Regen) and λ(Re, He).
Praca przedstawia sposoby określenia współczynnika oporów rurociągu λ, dla jednorodnej hydromieszaniny osadów pokoagulacyjnych o różnym uwodnieniu i różnej temperaturze, dla laminarnej strefy przepływu. Ocenę reologiczną hydromieszaniny, jako ciała plastyczno-lepkiego, wykonano na podstawie pomiarów wiskozymetrycznych, przy zastosowaniu do aproksymacji krzywych płynięcia uogólnionego modelu Vočadli. Określenie współczynnika oporu rurociągu λ przeprowadzono z wykorzystaniem bezwymiarowego kryterium λ(Regen) oraz λ(Re, He).
Źródło:
Archives of Environmental Protection; 2014, 40, 4; 39-51
2083-4772
2083-4810
Pojawia się w:
Archives of Environmental Protection
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modelowanie sił tłumiących występujących w układach perforowanych MEMS
Modelling of damping forces occurring in the perforated MEMS systems
Autorzy:
Urbanowicz, K.
Janczewski, J.
Powiązania:
https://bibliotekanauki.pl/articles/210825.pdf
Data publikacji:
2015
Wydawca:
Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
Tematy:
MEMS
siły tłumiące
równanie Reynoldsa
perforacja
damping forces
Reynolds equation
perforation
Opis:
Na pracę wielu układów mikroelektromechanicznych MEMS duży wpływ wywierają siły tłumiące wynikające z istnienia pomiędzy płytkami tzw. filmu powietrznego. Analityczne metody szacowania tych sił występują jedynie w prostych układach. Przy bardziej złożonych kształtach bardzo pomocne są metody numeryczne, których intensywny rozwój jest szczególnie zauważalny w ostatnich latach. Wśród paru znanych na rynku programów umożliwiających analizę układów MEMS wyróżnić można program Comsol Multiphysics, który zawiera specjalistyczny moduł MEMS. Wniniejszej pracy zostanie zweryfikowana przydatność powyższego programu w modelowaniu prostych oraz złożonych płytek zawierających perforacje w postaci otworów. Celem wykonywania w płytkach otworów jest przeważnie chęć redukcji występujących sił tłumiących. Zrealizowany szereg badań analityczno-numerycznych zobrazował liczne niedoskonałości programu Comsol, które należałoby poprawić.
Operation of many micro-electromechanical systems (MEMS) is highly influenced by damping forces resulting from the existence of fluid film between the MEMS plates. Analytical methods for estimating of these forces are presented only for simple plates. For more complex shapes of plates, numerical methods are very helpful. Among a few famous market programs, enabling analysis of MEMS, we can distinguish the program called Comsol Multyphysics which includes a specific module for MEMS. In this paper, the suitability of this program for modelling of simple and more complex plates with perforations in the form of holes will be verified. The tile holes are usually made in order to reduce occurring damping forces. The performed analytical and numerical studies, showed numerous imperfections of the Comsol program which needs to be improved by their programmers.
Źródło:
Biuletyn Wojskowej Akademii Technicznej; 2015, 64, 4; 191-206
1234-5865
Pojawia się w:
Biuletyn Wojskowej Akademii Technicznej
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Liczby kryterialne w charakterystyce wężownicowego wymiennika ciepła
Criterion numbers in characteristics of a coil heat exchanger
Autorzy:
Smusz, Robert
Wilk, Joanna
Powiązania:
https://bibliotekanauki.pl/articles/194733.pdf
Data publikacji:
2019
Wydawca:
Politechnika Rzeszowska im. Ignacego Łukasiewicza. Oficyna Wydawnicza
Tematy:
wężownica
liczba Deana
krytyczna liczba Reynoldsa
coil
Dean number
critical Reynolds number
Opis:
W artykule zaprezentowano przegląd literaturowy oraz analizę porównawczą dotyczącą liczb kryterialnych istotnych w opisie i projektowaniu wężownicowych wymienników ciepła – liczby Deana i krytycznej liczby Reynoldsa. Liczby te uwzględniają specyfikę przepływu płynu w wężownicy powstałej przez nawinięcie rury o przekroju kołowym na walcowej pobocznicy. Omówiono również geometrię wężownicy niezbędną w opisie liczb kryterialnych ze względu na istotny wpływ parametrów geometrycznych na strukturę przepływu. Dokonana analiza porządkuje zakresy stosowalności odpowiednich wzorów kryterialnych w zastosowaniu do opisu zjawisk związanych z intensyfikacją wymiany ciepła w wężownicowym wymienniku, wynikającą z pojawienia się przepływu wtórnego, który jest efektem interakcji siły odśrodkowej, sił bezwładności oraz sił wywołanych lepkością płynu.
The article presents a literature review and a comparative analysis of criterion numbers important in the description and design of coil heat exchangers - the Dean number and the critical Reynolds number. These numbers take into account the specificity of fluid flow in the coil resulting from winding of the circular section pipe on the cylindrical side. Coil geometry necessary in the description of criterion numbers was also discussed due to the significant influence of geometric parameters on the flow structure. The work analyzes the scope of applicability of appropriate criterion formulas in the description of phenomena related to intensification of heat transfer in the coil heat exchanger resulting from the occurrence of secondary flow, which is the effect of interaction of centrifugal forces, inertia forces and forces caused by fluid viscosity.
Źródło:
Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika; 2019, z. 91 [299], 1-2; 67-78
0209-2689
2300-5211
Pojawia się w:
Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Pomiar kryzą segmentową strumienia medium dla małych liczb Reynoldsa
Measurement with segmental orifice of flow medium for small Reynolds numbers
Autorzy:
Mrowiec, A.
Kasprzak, D.
Powiązania:
https://bibliotekanauki.pl/articles/267014.pdf
Data publikacji:
2016
Wydawca:
Politechnika Gdańska. Wydział Elektrotechniki i Automatyki
Tematy:
kryza segmentowa
liczba Reynoldsa
współczynnik przepływu
segmental orifice
Reynolds number
flow factor
Opis:
Podstawowym surowcem energetycznym w Polsce jest węgiel. W ostatnich latach podejmowano próby spalania koloidalnych zawiesin pyłu węglowego w oleju napędowym lub opałowym. Przy pomiarach przepływu takich zawiesin, może dochodzić do wytrącania i zalegania w układach przesyłowych osadów, co w efekcie może prowadzić do zaburzeń strumienia przepływu. Wiarygodność pomiaru tego parametru, mogą zapewnić kryzy segmentowe. W artykule zaprezentowano wyniki badań przepływowych kryz segmentowych z przytarczowym punktowym odbiorem ciśnienia różnicowego, przy niewielkich liczbach Reynoldsa oraz symulacje numeryczne dla wybranej kryzy. W badaniach jako medium wykorzystano wodę.
In Poland coal is the main energy resource. As part of the conducted research attempts were made at using suspensoids containing coal dust in gas oil and furnace oil. This leads to a reduction in NOx and SOx percentage without the need for an expensive desulphurization and dust extraction installation. However, there is a need for using cheap but reliable systems to measure the flow of the injected fuel. In real operating conditions various residues may often deposit in fuel transmission systems, which in turn can lead to flow fluctuations. Reliable flow factor measurement requirements can be met by segmental orifices. In the article, based on a research and measurement station, presented were the results of flow measurements with segmental orifices with point reception of differential pressure for small Reynolds numbers as well as numerical simulations. For the selected segmental orifice the flow factor characteristic in the function of the Reynolds number was calculated. In the research, water was used as the medium; the next stage of the research will involve the realization of the proposed solution with the use of hydraulic oil.
Źródło:
Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej; 2016, 49; 75-78
1425-5766
2353-1290
Pojawia się w:
Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of time-averaged secondary flow cells in wide and narrow straight open channels with lateral bed deformation
Autorzy:
Chattopadhyay, T.
Kundu, S.
Powiązania:
https://bibliotekanauki.pl/articles/38695706.pdf
Data publikacji:
2023
Wydawca:
Instytut Podstawowych Problemów Techniki PAN
Tematy:
turbulent flow
secondary current
method of separation of variable
Reynolds shear stress
Opis:
The usual cellular pattern of the time averaged secondary flow circulation in the central section of wide open channels shows a distorted (laterally or vertically) structure due to the changes in bed configurations along lateral direction. The structures of these secondary circulations (under different bed configurations) are crucial for different types of hydraulic modeling. This study presents mathematical models of the time averaged secondary velocities (lateral and vertical components) for a turbulence-induced secondary current at the central section of a wide open-channel flow under different types of elevated and non-elevated bed conditions. Starting with the Reynolds Averaged Navier-Stokes equation and using the continuity equation, at first the governing equation of secondary flow velocity is obtained including the effects of the eddy viscosity and viscosity of the fluid. The model equations is solved using a separation of the variable technique imposing the bed perturbation condition. Full analytical solutions are achieved through mathematical analysis using suitable boundary conditions consistent with experimental observations. Initially the models are derived for a non-elevated bedforms comprised of alternating equal widths of smooth and rough bed strips. These models are modified further for bedforms with unequal widths of rough and smooth bed strips and elevated periodic bed structures. Four different types of elevated bed configurations are investigated and a general approach is suggested for other types of bed forms. All the proposed models are validated with existing experimental results to ensure the applicability and in each cases, improved results are observed. Obtained results show that the centre of circulation of the cellular structure occurs above the junction of the rough and smooth bed strips (consistent with experimental observations) and it gradually shifts towards the smooth strip, when the length of the rough bed strip is increased. The shifting as a function shows a non-linear pattern with the length of the rough bed strip. A least-square model is proposed to identify the circulation center as a function of the ratio of rough to smooth bed strips. It is also found that the vertically distorted secondary cells are generated when the bed slope strictly increase/decrease throughout the length of the one whole circulation. Finally, all the proposed models are compared with an existing model and an error analysis is done. Results of error analysis show that the present study can be more suitable as it yields improved results.
Źródło:
Archives of Mechanics; 2023, 75, 1-2; 169-211
0373-2029
Pojawia się w:
Archives of Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Flow of viscous incompressible MHD fluid over a suddenly accelerated plate with variable electroconductivity and chemical reaction provoked by radiation
Autorzy:
Ngiangia, Alalibo T.
Powiązania:
https://bibliotekanauki.pl/articles/1191366.pdf
Data publikacji:
2016
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Chemical reaction
Electrconductivity
Grashof number
MHD
Prandtl number
Radiation
Reynold’s Number
Opis:
A study of a suddenly accelerated plate with variable approximated electronegativity with MHD fluid provoked by chemical reaction and radiation is made. The governing hydrodynamical equations of the physical problem was formulated and its solution and analysis showed that increase in electroconductivity, prandtl number, Reynold’s number, Grashof number, chemical reaction and radiation all result to a corresponding increase in the velocity profile of the fluid while magnetic field increase results to a decrease in the velocity profile of the fluid. The shear stress at the wall of the plate was also determined.
Źródło:
World Scientific News; 2016, 34; 135-145
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Elastohydrodynamic Contact Model for Calculation of Axial and Angular Stiffness in Thrust Bearing
Elastohydrodynamiczny model kontaktowy do obliczeń sztywności osiowej i kątowej łożysk oporowych
Autorzy:
Temis, M.
Lazarev, A.
Powiązania:
https://bibliotekanauki.pl/articles/140221.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
thrust bearing
elastohydrodynamic contact
Reynolds equation
łożysko oporowe
kontakt elastohydrodynamiczny
równanie Reynoldsa
Opis:
Thrust bearing model is developed for fluid flow calculation and for determination of bearing integral characteristics in the presence of sliding surfaces closure and shaft angular displacements. The model is based on the coupled solution of the problem of incompressible fluid flow between the sliding surfaces and the problem of bearing and shaft elements deformation under the action of the fluid film pressure. Verification of the bearing model results is carried out by the comparison versus the fluid flow calculation results obtained by STAR-CD software and the experimental and theoretical results represented in the certain literature. Thrust bearing characteristics are determined versus sliding surfaces closure and rotating disk (runner) angular displacements. The contribution of the sliding surfaces deformations into bearing integral characteristics is estimated.
Opracowano model łożyska oporowego przeznaczony do obliczeń przepływu płynu i wyznaczania całościowych charakterystyk dla warunków gdy występuje zamknięcie szczeliny między ślizgającymi się powierzchniami i kątowe przemieszczenie wału. Model jest oparty na połączonych rozwiązaniach zagadnienia przepływu nieściśliwego płynu między ślizgającymi się powierzchniami i zagadnienia deformacji elementów łożyska i wału pod wpływem ciśnienia w warstwie płynu. Weryfikacja wyników modelu łożyska jest przeprowadzona przez ich porównanie z wynikami obliczeń przepływu płynu uzyskanymi przy użyciu oprogramowania STAR-CD oraz wynikami eksperymentalnymi i teoretycznymi podawanymi w literaturze. Charakterystyki łożyska ślizgowego są wyznaczone z uwzględnieniem zamknięcia szczeliny smarnej i przemieszczeń kątowych tarczy obrotowej (oporowej). Oszacowano wpływ, jaki mają odkształcenia ślizgających się powierzchni na całościowe charakterystyki łożyska.
Źródło:
Archive of Mechanical Engineering; 2012, LIX, 4; 453-467
0004-0738
Pojawia się w:
Archive of Mechanical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
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