scholarly journals On a viscous two-fluid channel flow including evaporation

2018 ◽  
Vol 16 (1) ◽  
pp. 9-15
Author(s):  
Jürgen Socolowsky
Keyword(s):  
Channel Flow ◽  
Coupled System ◽  
Immiscible Fluids ◽  
Point Of View ◽  
Navier Stokes ◽  
Small Data ◽  
Free Interface ◽  
Weighted Hölder Spaces ◽  
Analytical Point ◽  
Fluid Channel

AbstractIn this contribution a particular plane steady-state channel flow including evaporation effects is investigated from analytical point of view. The channel is assumed to be horizontal. The motion of two heavy viscous immiscible fluids is governed by a free boundary value problem for a coupled system of Navier-Stokes and Stephan equations. The flow domain is unbounded in two directions and the free interface separating partially both liquids is semi-infinite, i.e. infinite in one direction. The free interface begins in some point Q where the half-line Σ1 separating the two parts of the channel in front of Q ends. Existence and uniqueness of a suitable solution in weighted HÖLDER spaces can be proved for small data (i.e. small fluxes) of the problem.

scholarly journals ON A TWO-FLUID INCLINED FILM FLOW WITH EVAPORATION

2013 ◽  
Vol 18 (1) ◽  
pp. 22-31
Author(s):  
Jürgen Socolowsky
Keyword(s):  
Existence And Uniqueness ◽  
Film Flow ◽  
Weighted Sobolev Spaces ◽  
Coupled System ◽  
Navier Stokes ◽  
Small Data ◽  
Free Boundary Value Problem ◽  
Data Perturbation ◽  
Flow Domain ◽  
Two Fluid

This paper is concerned with a plane steady-state inclined film flow including evaporation effects. The motion is governed by a free boundary value problem for a coupled system of Navier–Stokes and Stefan equations. The flow domain is unbounded in two directions and it contains a geometrical perturbation on the inclined bottom. Existence and uniqueness of a suitable solution in weighted Sobolev spaces can be proved for small data (perturbation, inclination of the bottom) characterizing the problem.

Social Justice and Critical/Performative Communicative Pedagogy

2011 ◽  
Vol 4 (1) ◽  
pp. 21-34 ◽  
Author(s):  
John T. Warren
Keyword(s):  
Qualitative Research ◽  
Social Justice ◽  
Classroom Interactions ◽  
Point Of View ◽  
Constitutive Relationship ◽  
Just World ◽  
The World ◽  
Analytical Point ◽  
Embodied Pedagogy

Through narratives and critical interrogations of classroom interactions, I sketch an argument for a co-constitutive relationship between qualitative research and pedagogy that imagines a more reflexive and socially just world. Through story, one comes to see an interplay between one's own experiences, one's own desires and one's community — I seek to focus that potential into an embodied pedagogy that highlights power and, as a result, holds all of us accountable for our own situated-ness in systems of power in ways that grant us potential places from which to enact change. Key in this discussion is a careful analytical point of view for seeing the world and a set of practices that work to imagine new ways of talking back.

On the Impact of Aptness, Conventionality and Familiarity on Metaphor Processing from a Meta-analytical Point of View

2020 ◽  
Vol 6 (1) ◽  
pp. 55-106
Author(s):  
Csilla Rákosi
Keyword(s):  
Meta Analysis ◽  
Point Of View ◽  
Psycholinguistic Research ◽  
Analytical Point ◽  
Metaphor Processing ◽  
The Impact

Psycholinguistic research into metaphor processing is burdened with empirical problems as experiments provide diverging evidence on the impact of conventionality, familiarity and aptness, and with conceptual issues as the interpretation and operationalization of the three concepts mentioned, as well as the related predictions which can be drawn from theories of metaphor processing, are controversial in the literature. This paper uses tools of statistical meta-analysis in order to bring us closer to the solution of these problems and reveal future lines of research.

scholarly journals Processing Effect and Characterization of Olive Oils from Spanish Wild Olive Trees (Olea europaea var. sylvestris)

Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1304
Author(s):  
Francisco Espínola ◽  
Alfonso M. Vidal ◽  
Juan M. Espínola ◽  
Manuel Moya
Keyword(s):  
Phenolic Compounds ◽  
Volatile Compounds ◽  
Olive Tree ◽  
Extraction Yield ◽  
Point Of View ◽  
Human Consumption ◽  
Analytical Point ◽  
Wild Olive ◽  
Olive Trees

Wild olive trees have important potential, but, to date, the oil from wild olives has not been studied significantly, especially from an analytical point of view. In Spain, the wild olive tree is called “Acebuche” and its fruit “Acebuchina”. The objective of this work is to optimize the olive oil production process from the Acebuchina cultivar and characterize the oil, which could be marketed as healthy and functional food. A Box–Behnken experimental design with five central points was used, along with the Response Surface Methodology to obtain a mathematical experimental model. The oils from the Acebuchina cultivar meet the requirements for human consumption and have a good balance of fatty acids. In addition, the oils are rich in antioxidants and volatile compounds. The highest extraction yield, 12.0 g oil/100 g paste, was obtained at 90.0 min and the highest yield of phenolic compounds, 870.0 mg/kg, was achieved at 40.0 °C, and 90.0 min; but the maximum content of volatile compounds, 26.9 mg/kg, was obtained at 20 °C and 30.0 min. The oil yield is lower than that of commercial cultivars, but the contents of volatile and phenolic compounds is higher.

scholarly journals Statistical Uncertainty of DNS in Geometries without Homogeneous Directions

2021 ◽  
Vol 11 (4) ◽  
pp. 1399
Author(s):  
Jure Oder ◽  
Cédric Flageul ◽  
Iztok Tiselj
Keyword(s):  
Channel Flow ◽  
A Priori ◽  
Time Integration ◽  
Navier Stokes ◽  
Statistical Uncertainty ◽  
Time Step ◽  
Order Of Magnitude ◽  
Averaging Time ◽  
The Individual ◽  
Time Required

In this paper, we present uncertainties of statistical quantities of direct numerical simulations (DNS) with small numerical errors. The uncertainties are analysed for channel flow and a flow separation case in a confined backward facing step (BFS) geometry. The infinite channel flow case has two homogeneous directions and this is usually exploited to speed-up the convergence of the results. As we show, such a procedure reduces statistical uncertainties of the results by up to an order of magnitude. This effect is strongest in the near wall regions. In the case of flow over a confined BFS, there are no such directions and thus very long integration times are required. The individual statistical quantities converge with the square root of time integration so, in order to improve the uncertainty by a factor of two, the simulation has to be prolonged by a factor of four. We provide an estimator that can be used to evaluate a priori the DNS relative statistical uncertainties from results obtained with a Reynolds Averaged Navier Stokes simulation. In the DNS, the estimator can be used to predict the averaging time and with it the simulation time required to achieve a certain relative statistical uncertainty of results. For accurate evaluation of averages and their uncertainties, it is not required to use every time step of the DNS. We observe that statistical uncertainty of the results is uninfluenced by reducing the number of samples to the point where the period between two consecutive samples measured in Courant–Friedrichss–Levy (CFL) condition units is below one. Nevertheless, crossing this limit, the estimates of uncertainties start to exhibit significant growth.

Pontryagin maximum principle and second order optimality conditions for optimal control problems governed by 2D nonlocal Cahn–Hilliard–Navier–Stokes equations

Analysis ◽  
2020 ◽  
Vol 40 (3) ◽  
pp. 127-150
Author(s):  
Tania Biswas ◽  
Sheetal Dharmatti ◽  
Manil T. Mohan
Keyword(s):  
Optimal Control ◽  
Optimal Control Problem ◽  
Control Problem ◽  
Stokes Equations ◽  
Minimum Principle ◽  
Immiscible Fluids ◽  
Second Order ◽  
Navier Stokes ◽  
Distributed Optimal Control ◽  
Navier Stokes Equations

AbstractIn this paper, we formulate a distributed optimal control problem related to the evolution of two isothermal, incompressible, immiscible fluids in a two-dimensional bounded domain. The distributed optimal control problem is framed as the minimization of a suitable cost functional subject to the controlled nonlocal Cahn–Hilliard–Navier–Stokes equations. We describe the first order necessary conditions of optimality via the Pontryagin minimum principle and prove second order necessary and sufficient conditions of optimality for the problem.

Burgers turbulence model for a channel flow

1971 ◽  
Vol 47 (2) ◽  
pp. 321-335 ◽  
Author(s):  
Jon Lee
Keyword(s):  
Channel Flow ◽  
Stokes Equations ◽  
Turbulent Channel Flow ◽  
Reynolds Numbers ◽  
Navier Stokes ◽  
Amplitude Equations ◽  
Fourier Amplitude ◽  
Navier Stokes Equations ◽  
Burgers Model ◽  
Model Dynamics

The truncated Burgers models have a unique equilibrium state which is defined continuously for all the Reynolds numbers and attainable from a realizable class of initial disturbances. Hence, they represent a sequence of convergent approximations to the original (untruncated) Burgers problem. We have pointed out that consideration of certain degenerate equilibrium states can lead to the successive turbulence-turbulence transitions and finite-jump transitions that were suggested by Case & Chiu. As a prototype of the Navier–Stokes equations, Burgers model can simulate the initial-value type of numerical integration of the Fourier amplitude equations for a turbulent channel flow. Thus, the Burgers model dynamics display certain idiosyncrasies of the actual channel flow problem described by a truncated set of Fourier amplitude equations, which includes only a modest number of modes due to the limited capability of the computer at hand.

Time to get up

2010 ◽  
Vol 20 (1) ◽  
pp. 69-89 ◽  
Author(s):  
Peter Backhaus
Keyword(s):  
Elderly Care ◽  
Care Facility ◽  
Point Of View ◽  
Care Workers ◽  
Analytical Point ◽  
Japanese Elderly ◽  
Compliance Gaining

This paper looks at compliance-gaining interaction in a Japanese elderly care facility from a conversation analytical point of view. Focus is on the various ways compliance is sought for by the caring staff with getting the residents out of bed and starting the daily morning care procedures. Three extracts are discussed in detail. The analysis shows how the residents in all three cases display clear signs of resistance to get up, but finally have to submit to the planned course of actions pursued by the care workers. A closer look at how this is played out in interaction suggests that the residents’ compliance is enforced rather than gained.

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