Capillary Instability of a Streaming Fluid - Core Liquid Jet Under Their Self Gravitating Forces

• Autorzy: Radwan A. E. , Elmahdy E. E.
• Języki publikacji: EN

Abstrakty

EN

The stability criterion of a fluid cylinder (density p) embedded into a different fluid (density p¹) is derived and discussed. The model is capillary unstable in the domain 0<xə as m = 0 where x and m are the axial and transverse wave numbers, while it is stable in all other domains. The densities ratio p¹ /p decreases the unstable domains but never suppress them. The streaming increases the unstable domains. Gravitationally, in m = 0 mode the model is unstable in the domain 0 < x < 1.0668 as p¹ < p, while as p¹ = p it is marginally stable but when p¹ > p the model is purely unstable for all short and long wavelengths. In m≠0 modes the self-gravitating model is neutrally stable as p = p¹ and ordinary stable as p¹ < p but it is purely unstable as p¹ > p. The streaming destabilizing effect makes the self-gravitating instability worse and shrinks the stable domains. The stability analysis of the model under the combined effect of the capillary and self-gravitating forces is performed analytically and verified numerically. When p¹ < p the capillary force and the axial flow have destabilizing influences but the densities ratio p¹/p has a stabilizing effect on the gravitating instability. If p = p¹ the streaming is destabilizing but the capillary force is strongly stabilizing and could suppress the gravitational instability. When p¹ > p the capillary force improved the gravitational instability and created much domains of stability and moreover the instability of the self-gravitating force disappeared in several cases of axisymmetric disturbances.

Słowa kluczowe

EN

capillary; streaming fluid; gravity forces

PL

kapilary; grawitacja

• Wydawca: Wydawnictwo Politechniki Łódzkiej
• Czasopismo: Mechanics and Mechanical Engineering
• Rocznik: 2005
• Tom: Vol. 9, nr 2
• Strony: 131--145
• Opis fizyczny: Bibliogr. 14 poz.

Twórcy

autor

Radwan A. E.

• Mathematics Department, Faculty of Science, Ain-Shams University Cairo, Egypt

autor

Elmahdy E. E.

• Mathematics Department, Faculty of Science, Tanta University, Tanta, Egypt

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