Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 4

Liczba wyników na stronie
first rewind previous Strona / 1 next fast forward last
Wyniki wyszukiwania
Wyszukiwano:
w słowach kluczowych:  elimination of pressure
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 1 next fast forward last
1
Content available remote Przepływ cieczy lepkiej w obszarze prostokątnym z półwyspem
PL
Tematem pracy jest wyznaczenie nieustalonego przepływu cieczy lepkiej w obszarze prostokątnym z ruchomą ścianką oraz wewnętrzną przegrodą. Zastosowana w pracy metoda obliczeniowa pełnych, nieuproszczonych równań Naviera-Stokesa oparta jest na sposobie eliminowania ciśnienia drogą wyznaczenia całki po konturze zamkniętym z różniczki zupełnej ciśnienia. W pracy przedstawiono wyniki obliczeń dla Re = 600 przy różnych ustawieniach przegrody wewnątrz obszaru przepływu.
EN
A numerical simulation of the flow of viscous incompressible fluid in a rectangular cavity with a division wall is a subject of this paper (Re = 600). The simulation has been done applying the method of elimination of the pressure from the Navier-Stokes equations by determination of the contour integral of the total differantial of the pressure.
EN
Similarly as the preceding paper of the authors (Klonowska and Kołodziejczyk, 1999) also the present one deals with the new method (Prosnak and Kosma, 1991) for the determination of unsteady, plane flows of viscous incompressible fluids. The novelty of the method consists in elimination of pressure from the system of the Navier-Stokes equations by means of integration of the "total" differential of pressure. Consequently - the order of the system resulting from such an elimination is not increased in comparison with the original one, and no artificial, non-physical boundary conditions occur. The main difference between the present paper and the previous one consists in geometrical properties of the domain of solution. It is infinite, and bounded by a curvilinear contour. Three contours are considered in the paper: a flat plate, a circle, and the NACA 0012 airfoil. The results prove, that also in these cases the method works properly - at least for rather small values of the Reynolds number. Such a limitation is due to the efficiency of the computers being available at the time, when the calculations were made.
EN
It is shown that two particular systems of linear equations, derived in an earlier paper by Prosnak and Kosma (1991), can be solved in an exact time- and storage-saving manner. First of all, by the proper elimination of unknowns, each system can be reduced to a smaller one containing only half of the unknowns. In the first case, the matrix of coefficients of the so reduced system turns out to be tridiagonal, its elements consisting of square submatrices. Moreover, the reduced system can be split into two independent ones. In the second case, the matrix of the reduced system can be presented as the product of two triangular ones, each one being partitioned in square submatrices. Corresponding algorithms and computer programs have been developed in order to investigate whether some economy in storage and computing time is really attainable. Affirmative conclusions are drawn from the results of computations. This means that the new method of solving problems governed by the Navier-Stokes equations, presented in the cited paper, can be applied in a more effective manner.
EN
The paper deals with a new method (Prosnak and Kosma, 1991) for the determination of unsteady, plane flows of viscous incompressible fluids. The characteristic feature of the method consists in elimination of pressure from the system of the Navier-Stokes equations governing the flow - in such a manner that the order of the resulting system is not increased in comparison with the original one. Furthermore, the mathematical problem posed for the resulting system is reduced in the frame of the method to an initial problem for a system of first order ordinary differential equations, wherein time represents the only independent variable. The nonlinearities of the Navier-Stokes equations do not cause any difficulties by virtue of such an approach. In this paper, the method has been applied to flows in plane, finite rectangular domains, and domains composed of rectangles. Numerical solutions to such problems are presented in the paper in graphical form, and some conclusions are drawn concerning the results as well as the method.
first rewind previous Strona / 1 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.