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11.
Juray De Wilde Denis Constales Geraldine J. Heynderickx Guy B. Marin 《International Journal of Multiphase Flow》2007
The propagation speeds of linear waves in gas–solid suspensions depend strongly on the solids volume fraction and the wave frequency. The latter is due to gas–solid momentum transfer and allows a simple test on filtered gas–solid momentum transfer models. Such models may predict linear wave propagation speeds different from those obtained with the non-filtered model at wave frequencies higher than the filter frequency, but not at wave frequencies lower than the filter frequency. 相似文献
12.
The problem considered is that of determining the shape of aplane acoustically sound-soft obstacle from the knowledge ofthe far-field pattern for one time-harmonic incident field.An iterative procedure is proposed based on two boundary integralsrepresenting the incident field and the far-field pattern, respectively.Numerical examples are included which show that the proceduregives accurate numerical approximations in relatively few iterations. 相似文献
13.
Speed of sound and density of 1-propanol + heavy water were measured in the whole concentration range at temperatures from 293 to 313 K. Isentropic compressibility was calculated from the Laplace formula. The partial molar volume of 1-propanol reaches a minimum at the mole fraction of 1-propanol x
1 0.03. At the same concentration, the compressibility isotherms intersect one another. These features of the investigated system are similar to those of 1-propanol + H2O, that points to essential similarity of the two mixtures. A clathrate-like structure was suggested to explain the experimental results for dilute solutions of the alcohol. Somewhat more pronounced hydrophobic hydration in D2O than in H2O is manifested by an effect similar to that resulting from the elongation of the alcohol molecule. 相似文献
14.
I. Gascón S. Martín P. Cea M. C. López F. M. Royo 《Journal of solution chemistry》2002,31(11):905-915
Densities and speeds of sound of the binary mixtures 1,3-dioxolane + 1-butanol, 1,3-dioxolane + 2-butanol, 1,4-dioxane + 1-butanol, and 1,4-dioxane + 2-butanol have been measured at 25 and 40°C. The excess molar volumes and excess isentropic compressibility coefficients were calculated from experimental data and fitted to a Redlich–Kister polynomial function. Results were analyzed in terms of molecular interactions and compared with literature data. 相似文献
15.
Metal foams: A survey 总被引:37,自引:0,他引:37
The current state-of-the-art in the development of cellular metal foams is reviewed, with focus on their fabrication, mechanical/thermal/acoustic properties, and potential applications as lightweight panels, energy absorbers, heat exchangers, and acoustic liners. Foam property charts with scaling relations are presented, allowing scoping and selection through the use of material indices. 相似文献
16.
B. Pateyron M. F. Elchinger G. Delluc P. Fauchais 《Plasma Chemistry and Plasma Processing》1996,16(1):39-57
In most cases the energy dissipated in plasma jets used either,for heating or spraying is varied by changing the are current, the total gas floc+rate, and composition. However, when doing so, conditions are reached where the plasma jet may become supersonic. To predict such conditions or to characterize supersonic plasma jets the knowledge of the sound velocitya is mandatory The goal of this paper is to calculatea versus plasma forming gas composition, temperature, and pressure. Rigorous calculation would imply the knowledge of the chemical reaction kinetics, sound velocity depending strongly on this. Unfortunately such kinetics are generally lolknown for plasma jet floras and the only possibility is to determine the equilibrium sound velocitya calculated through the isentropic coefficient T. This coefficient has been calculated taking into account the dissociation and ionization reactions at equilibrium for temperatures ranging from 300 to 25,000 K and pressures between 0.1 and 1 Mpa for Ar, H2, He, Ar-He, Ar-H2, O2, N2, air, .steam, and methane.a often called the frozen sound velocity, was also calculated using (ratio of specific heats) instead of . 相似文献
17.
The speed of sound u in and densities of eight binary mixtures of p-dioxane (p-C4H8O2) with methylcyclohexane (c-C6H11CH3), 1-chlorohexane (C6H13C1), 1-bromohexane (C6H13Br), p-xylene [C6H4(CH3)2], propylbenzene (C6H5C3H7), methyl acetate CH3COOCH3), butyl acetate (CH3COOC4H9), and amyl acetate (CH3COOC5H11) were measured over the whole composition range at 30°C. Isentropic compressibilities (K
S), Rao's molar sound functions (R), excess molar volumes (V
E), excess isentropic compressibilities (K
S
E
) together with relative change in volume V/12 values, have been obtained for all measured mole fractions. The excess partial molar volume (V1-V
1
0
) of p-dioxane in different solvents have also been estimated. The experimental results have been analyzed in terms of the Prigogine–Flory–Patterson theory of solutions. 相似文献
18.
The selection of the correct mixing rule for sound velocity in ideal liquid mixtures determines the interpretation of the sound velocity in real mixtures. This is especially important for the determination of apparent properties of solutes, such as their apparent compressibility. There are different approaches reported in the literature, and this article presents a new derivation of the mixing rule based on statistical mechanics. It is shown that the correlation of volume fluctuations between adjacent components has a crucial influence on the ideal mixing rule. 相似文献
19.
Rayleigh-Brillouin light scattering experiments were performed on gelatin gels in order to obtain the (hypersonic) sound velocity and sound attenuation as a function of gelatin concentration. The results show that in the high frequency regime there is a strong coupling in the gel between the dynamics of the network and that of the fluid. The network sound velocity varies with
1/2. Sound attenuation increases with increasing gelatin concentration. 相似文献
20.
J. Canosa 《The Journal of chemical thermodynamics》2003,35(12):2021-2031
Density, refractive index and speed of sound at T=298.15 K and atmospheric pressure have been measured over the entire composition range for (dimethyl carbonate (DMC) + methanol + ethanol) and (DMC + methanol + 1-propanol). Excess molar volumes, changes of refractive index on mixing and deviations in isentropic compressibility for the above systems have been calculated. The calculated quantities are further fitted to the Cibulka equation to estimate the ternary fitting parameters. Standard deviations from the regression lines are shown. 相似文献