scispace - formally typeset
Journal ArticleDOI

A study of Taylor instability of superposed fluids

01 Mar 1976-Acta Mechanica (Springer Science and Business Media LLC)-Vol. 24, Iss: 1, pp 87-97

TL;DR: In this article, a solution of hydrodynamic equations for the case of (Taylor) instability of the interface of two fluids of different but constant densities when accelerated from the heavier fluid to the lighter fluid is sought.

AbstractA solution of hydrodynamic equations for the case of (Taylor) instability of the interface of two fluids of different but constant densities when accelerated from the heavier fluid to the lighter fluid is sought. After identifying the problem as one of singular perturbation, it is solved by the method of strained coordinates. A third order theory is presented. It is found that the ratio of the densities of the fluids has a significant effect on the stability or growth of the interface. Growth of the interface is found to depend also on the wave number and amplitude of initial disturbance. Stability criterion is calculated for different values of density ratio.

...read more


Citations
More filters
Journal ArticleDOI
TL;DR: In this paper, the authors presented a method to identify the most important features of a given set of features in a set of images, and the article of record as published may be located at http://dx.doi.org/10.1017/S0022112093002514
Abstract: The article of record as published may be located at http://dx.doi.org/10.1017/S0022112093002514

46 citations


Cites result from "A study of Taylor instability of su..."

  • ...A long-wave analysis for this case (Appendix B) shows that the growth in the deforming regions again becomes catastrophic due to finite-amplitude effects, as in the Newtonian case. A companion work (Canright & Morris 1993) considers a different model for the lithosphere : as a thermal boundary layer growing under a suddenly cooled horizontal boundary, where the fluid viscosity depends strongly on temperature. The long-wave analysis shows that, again, the nonlinear effects of finite amplitude give catastrophic growth, yielding sheets in finite time. For that case the force balance and the resulting growth of peaks is essentially the same as that considered here, because thermal diffusion becomes unimportant where the layer is thick. The Rayleigh-Taylor problem considered here is the simplest example of this dynamic balance. The instability of a dense fluid supported by a lighter one has been studied extensively, beginning with the analysis of Rayleigh (1883). Taylor (1950) noted that acceleration would give the same effect as gravity, in agreement with the experiments of Lewis (1950). A thorough introduction to the linear theory is given by Chandrasekhar (1961, chap....

    [...]

  • ...A long-wave analysis for this case (Appendix B) shows that the growth in the deforming regions again becomes catastrophic due to finite-amplitude effects, as in the Newtonian case. A companion work (Canright & Morris 1993) considers a different model for the lithosphere : as a thermal boundary layer growing under a suddenly cooled horizontal boundary, where the fluid viscosity depends strongly on temperature. The long-wave analysis shows that, again, the nonlinear effects of finite amplitude give catastrophic growth, yielding sheets in finite time. For that case the force balance and the resulting growth of peaks is essentially the same as that considered here, because thermal diffusion becomes unimportant where the layer is thick. The Rayleigh-Taylor problem considered here is the simplest example of this dynamic balance. The instability of a dense fluid supported by a lighter one has been studied extensively, beginning with the analysis of Rayleigh (1883). Taylor (1950) noted that acceleration would give the same effect as gravity, in agreement with the experiments of Lewis (1950)....

    [...]

  • ...A long-wave analysis for this case (Appendix B) shows that the growth in the deforming regions again becomes catastrophic due to finite-amplitude effects, as in the Newtonian case. A companion work (Canright & Morris 1993) considers a different model for the lithosphere : as a thermal boundary layer growing under a suddenly cooled horizontal boundary, where the fluid viscosity depends strongly on temperature. The long-wave analysis shows that, again, the nonlinear effects of finite amplitude give catastrophic growth, yielding sheets in finite time. For that case the force balance and the resulting growth of peaks is essentially the same as that considered here, because thermal diffusion becomes unimportant where the layer is thick. The Rayleigh-Taylor problem considered here is the simplest example of this dynamic balance. The instability of a dense fluid supported by a lighter one has been studied extensively, beginning with the analysis of Rayleigh (1883). Taylor (1950) noted that acceleration would give the same effect as gravity, in agreement with the experiments of Lewis (1950). A thorough introduction to the linear theory is given by Chandrasekhar (1961, chap. X), and recent surveys of previous work are given by Sharp (1984) and Kull(l991). Many of the analyses (e.g. Bellman & Pennington 1954; and Menikoff et al. 1978) have focused on the initial small-amplitude growth, where linearized equations are appropriate. One approach for examining the nonlinear effects of large amplitude is direct numerical simulation, e.g. Harlow & Welch (1966) and Tryggvason (1988), or through boundary-integral computations, e....

    [...]

  • ...A long-wave analysis for this case (Appendix B) shows that the growth in the deforming regions again becomes catastrophic due to finite-amplitude effects, as in the Newtonian case. A companion work (Canright & Morris 1993) considers a different model for the lithosphere : as a thermal boundary layer growing under a suddenly cooled horizontal boundary, where the fluid viscosity depends strongly on temperature. The long-wave analysis shows that, again, the nonlinear effects of finite amplitude give catastrophic growth, yielding sheets in finite time. For that case the force balance and the resulting growth of peaks is essentially the same as that considered here, because thermal diffusion becomes unimportant where the layer is thick. The Rayleigh-Taylor problem considered here is the simplest example of this dynamic balance. The instability of a dense fluid supported by a lighter one has been studied extensively, beginning with the analysis of Rayleigh (1883). Taylor (1950) noted that acceleration would give the same effect as gravity, in agreement with the experiments of Lewis (1950). A thorough introduction to the linear theory is given by Chandrasekhar (1961, chap. X), and recent surveys of previous work are given by Sharp (1984) and Kull(l991). Many of the analyses (e.g. Bellman & Pennington 1954; and Menikoff et al. 1978) have focused on the initial small-amplitude growth, where linearized equations are appropriate. One approach for examining the nonlinear effects of large amplitude is direct numerical simulation, e.g. Harlow & Welch (1966) and Tryggvason (1988), or through boundary-integral computations, e.g. Baker & Meiron (1984), and Newhouse & Pozrikidis (1990). To investigate the nonlinear effects analytically, the most common approach has been the perturbation method, where various quantities are expressed as power series in the small initial amplitude or slope, giving linearized equations for each order (e.g. Emmons, Chang & Watson 1960). However, a wide variety of other methods have been employed (primarily for inviscid fluids) e.g. least-squares approximation (Kull 1986), averaging (Drazin 1969), multiple timescales (Nayfeh 1969), strained coordinates (Amaranath & Rajappa 1976), generalized coordinates (Dienes 1978), Lagrangian formulations (Ott 1972), and heuristic models (Baker & Freeman 1981; Aref & Tryggvason 1989). Also, Dussan V. (1975) used energy methods to determine the stability of disturbances of arbitrary amplitude. In the above studies, inertia is important. The situation we consider, of a thin viscous layer in creeping flow, has been examined primarily in the geophysics literature, e.g. the experiments and weakly nonlinear theory of Whitehead & Luther (1975). Our analysis is equivalent to a perturbation expansion in the interfacial slope, which for long waves remains small even for large amplitudes....

    [...]

  • ...A long-wave analysis for this case (Appendix B) shows that the growth in the deforming regions again becomes catastrophic due to finite-amplitude effects, as in the Newtonian case. A companion work (Canright & Morris 1993) considers a different model for the lithosphere : as a thermal boundary layer growing under a suddenly cooled horizontal boundary, where the fluid viscosity depends strongly on temperature. The long-wave analysis shows that, again, the nonlinear effects of finite amplitude give catastrophic growth, yielding sheets in finite time. For that case the force balance and the resulting growth of peaks is essentially the same as that considered here, because thermal diffusion becomes unimportant where the layer is thick. The Rayleigh-Taylor problem considered here is the simplest example of this dynamic balance. The instability of a dense fluid supported by a lighter one has been studied extensively, beginning with the analysis of Rayleigh (1883). Taylor (1950) noted that acceleration would give the same effect as gravity, in agreement with the experiments of Lewis (1950). A thorough introduction to the linear theory is given by Chandrasekhar (1961, chap. X), and recent surveys of previous work are given by Sharp (1984) and Kull(l991). Many of the analyses (e.g. Bellman & Pennington 1954; and Menikoff et al. 1978) have focused on the initial small-amplitude growth, where linearized equations are appropriate. One approach for examining the nonlinear effects of large amplitude is direct numerical simulation, e.g. Harlow & Welch (1966) and Tryggvason (1988), or through boundary-integral computations, e.g. Baker & Meiron (1984), and Newhouse & Pozrikidis (1990). To investigate the nonlinear effects analytically, the most common approach has been the perturbation method, where various quantities are expressed as power series in the small initial amplitude or slope, giving linearized equations for each order (e....

    [...]

Journal ArticleDOI
TL;DR: In this article, a solution of the hydrodynamic equations for the case of (Taylor) instability of the interface of two fluids of different but constant densities when accelerated from the heavier fluid to the lighter one near the linear cut-off wave number is sought.
Abstract: A solution of the hydrodynamic equations for the case of (Taylor) instability of the interface of two fluids of different but constant densities when accelerated from the heavier fluid to the lighter one near the linear cut-off wave number is sought. Since the PLK method does not lead to valid results near this wave number, we apply the method of multiple scales. It was shown that the interface grows even at the linear critical wave number and the density ratio plays a role in determining the nonlinear critical wave number.

References
More filters
Journal ArticleDOI
TL;DR: In this article, it was shown that when two superposed fluids of different densities are accelerated in a direction perpendicular to their interface, this surface is stable or unstable according to whether the acceleration is directed from the heavier to the lighter fluid or vice versa.
Abstract: It is shown that, when two superposed fluids of different densities are accelerated in a direction perpendicular to their interface, this surface is stable or unstable according to whether the acceleration is directed from the heavier to the lighter fluid or vice versa. The relationship between the rate of development of the instability and the length of wave-like disturbances, the acceleration and the densities is found, and similar calculations are made for the case when a sheet of liquid of uniform depth is accelerated.

2,611 citations

Journal ArticleDOI
TL;DR: In this article, the authors considered the model of two fluids of infinite depth, with the interface initially in the form of a sine wave with amplitude small compared to wave length, and only the linear terms in the equations of hydrodynamics were used.
Abstract: : The model used is that of two fluids of infinite depth, with the interface initially in the form of a sine wave with amplitude small compared to wave length. The fluids are considered incompressible, and only the linear terms in the equations of hydrodynamics are used. The first four sections discuss the effects of surface tension and viscosity. The fifth gives a few numerical results to illustrate the main points of the preceding sections.

388 citations

Journal ArticleDOI
TL;DR: In this paper, the instability of the accelerated interface between a liquid (methanol or carbon tetrachloride) and air has been investigated experimentally for approximate sinusoidal disturbances of wave-number range from well below to well above the cut-off.
Abstract: The instability of the accelerated interface between a liquid (methanol or carbon tetrachloride) and air has been investigated experimentally for approximate sinusoidal disturbances of wave-number range from well below to well above the cut-off. The growth rates are measured and compared with theoretical results. A third-order theory shows the phenomena of overstability which is found in the experimental results. Some measurements of later stages of growth agree moderately well with the available theory and disclose some additional phenomena of bubble competition, Helmholtz instability with transition to turbulence, and jet instability with production of drops.

136 citations

Journal ArticleDOI
TL;DR: In this paper, it was shown that the velocity field obtained by a straightforward expansion in powers of the disturbances, up to and including either the first or the second power, with coefficients functions of co-ordinates such that the leading edge is at the origin and the aerofoil chord is one of the axes, may be rendered a valid first approximation near the leading edges, as well as a valid second approximation away from it, if the whole field is shifted downstream parallel to the chord for a distance of half the leading-edge radius of curvature ρL.
Abstract: The general technique for rendering approximate solutions to physical problems uniformly valid is here applied to the simplest form of the problem of correcting the theory of thin wings near a rounded leading edge. The flow investigated is two-dimensional, irrotational and incompressible, and therefore the results do not materially add to our already extensive knowledge of this subject, but the method, which is here satisfactorily checked against this knowledge, shows promise of extension to three-dimensional, and compressible, flow problems. The conclusion, in the problem studied here, is that the velocity field obtained by a straightforward expansion in powers of the disturbances, up to and including either the first or the second power, with coefficients functions of co-ordinates such that the leading edge is at the origin and the aerofoil chord is one of the axes, may be rendered a valid first approximation near the leading edge, as well as a valid first or second approximation away from it, if the whole field is shifted downstream parallel to the chord for a distance of half the leading edge radius of curvature ρL. It follows that the fluid speed on the aerofoil surface, as given on such a straightforward second approximation as a function of distance x along the chord, similarly is rendered uniformly valid ( see equation (52)) if the part singular like x -1 is subtracted and the remainder is multiplied by .

86 citations

Journal ArticleDOI
01 Oct 1954
TL;DR: In this article, a solution of the hydrodynamical equations for the case of Taylor instability for two fluids of constant density is sought by the method of successive approximations.
Abstract: A solution of the hydrodynamical equations for the case of Taylor instability for two fluids of constant density is sought by the method of successive approximations. The expansion parameter is the initial amplitude of the interface; the validity of the method then assumes convergence of the series involved. The linear equations to be solved at the pth step for the pth order unknown fields are derived. The solution is actually carried out up to the second approximation. An interesting feature of this solution is that its time growth comports not only the integral modes exp (σt) and exp (2σt) but also the irrational mode exp (radical2σt), in terms of the growth parameter σ identical with {gk(ρ' - ρ) / (ρ' + ρ)}1/2.

28 citations