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231.
In this paper, the nonreflecting boundary conditions based upon fundamental ideas of the linear analysis are developed for
gas dynamic equations, and the modified boundary conditions for Navier-Stokes equations are proposed as a substitute of the
nonreflecting boundary conditions inside boundary layers near rigid walls. These derived boundary conditions are then applied
to calculations both for the Euler equations and the Navier-Stokes equations to determine if they can produce acceptable results
for the subsonic flows in channels. The numerical results obtained by an implicit second-order upwind difference scheme show
the effectiveness and generality of the boundary conditions. Furthermore, the formulae and the analysis performed here may
be extended to three dimensional problems.
recommended by Prof. Cui Erjie 相似文献
232.
Electrochemical polymerization of monosodium salt ( 1b ) of 6‐N,N‐dioctylamino‐1,3,5‐triazine‐2,4‐dithiol on stainless steels was investigated in zero (0T), perpendicular (5T⊥), and parallel (5T//) magnetic fields which are arranged perpendicular and parallel to the direction of electrolytic current. 5T⊥ magnetic field enhances the formation rate of poly(6‐N,N‐dioctylamino‐1,3,5‐triazine‐2,4‐disulfide) 2 films but suppresses the crystallinity of 2 . However, 5T// magnetic field enhances the formation rate and the crystallinity. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:60–64, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20257 相似文献
233.
234.
Kunio Esumi Hiroaki Matsui 《Colloids and surfaces. A, Physicochemical and engineering aspects》1993,80(2-3):273-278
The adsorption of polyvinylpyrrolidone (PVP) and poly(dimethyldiallylammonium chloride) (PDC) on silica from their mixed aqueous solutions has been investigated as a function of PVP concentration in the presence of PDC. The adsorption of PVP is almost unchanged with the feed concentration of PVP, while the adsorption of PDC decreases with increasing PVP concentration, especially at high concentrations of PDC. The conformation of PVP in the adsorbed layer on silica is relatively flat at low concentrations of PDC, but is extended in solution at high concentrations of PDC. The stability of the silica dispersion is low and the ζ potential is relatively small at low concentrations of PDC, whereas a stable dispersion is obtained at high concentrations of PDC and the ζ potential is large. Thus the stability of the dispersion is well correlated with the electrostatic repulsion and steric repulsion forces operating at the particles. 相似文献
235.
236.
Bao-chang Zhao Masato Tazawa Atsuo Kitade Kunio Yoshihara 《International Journal of Infrared and Millimeter Waves》1984,5(7):985-996
Conclusions From the results shown above, it may be said that this new spectroscopic method using the Fraunhofer diffraction pattern has the possibility of practical use. This method has the advantages that the multiplex gain is retained and the experimental apparatus is very simple as compared with the conventional grating spectroscopy. The resolution is about 1.25A/2KX and becomes higher with the increase of the number of slits and the maximum value of variable in the diffraction pattern. The other way, the simultaneous equations become more difficult to solve with the increase of resolution and at present the maximum value of NS is 21. In such a case the adjustment factor A and the figure of condition of matrix are important. Further, large memory of the electronic computer is required, for example, 2.56MB for N=800. The experimental setup is now under construction in order to verify the usefulness of this method in the far infrared region. 相似文献
237.
Projection method for solving a singular system of linear equations and its applications 总被引:4,自引:0,他引:4
Kunio Tanabe 《Numerische Mathematik》1971,17(3):203-214
Summary The iterative method for solving system of linear equations, due to Kaczmarz [2], is investigated. It is shown that the method works well for both singular and non-singular systems and it determines the affine space formed by the solutions if they exist. The method also provides an iterative procedure for computing a generalized inverse of a matrix. 相似文献
238.
239.
Introduction of t-butyl groups to the 2-, 3-, 2,4-, or 2,5-positions of 7-t-butyl-7-cyano-1,3,5-cycloheptatriene dramatically shifts the cycloheptatriene - norcaradiene equilibrium to the norcaradiene form. The nonbonded interaction is an important factor. 相似文献
240.