Instability of 2-D compressible gas jets in a viscous liquid medium
- Case Western Reserve Univ., Cleveland, OH (United States). Dept. of Mechanical Engineering
- Univ. of Waterloo, Ontario (Canada)
Bubbles from the disintegration of gas jets and sheets are of fundamental importance in many practical and industrial applications. Instability and breakup of gas sheets are conveniently utilized in chemical and pharmaceutical industries for gas dissolution in a liquid medium, in mining industries for coal and mineral preparation by froth floatation technique and in bubble plumes widely used for aeration, protection of structures against ocean waves and for mixing of stratified reservoirs. The instability of a plane compressible gas sheet in a quiescent viscous liquid medium of infinite expanse has been studied. It is found that there exist two unstable modes of disturbances, sinuous and varicose. For temporal instability, sinuous disturbance is stable if gas Weber number, defined as the ratio of aerodynamic to capillary forces, is less than unity, varicose mode controls the instability process except for large Weber numbers when both modes become equally important, and gas compressibility effect always enhances instability development and induces additional range of unstable wave numbers. For spatial-temporal evolution of disturbances, it is found that convective instability does not exist at all and the instability of plane gas sheets is always absolute in nature, which is strikingly opposite to the instability of plane liquid sheets. The absolutely unstable disturbance is found always temporally growing, although it may be spatially growing or decaying depending on flow conditions. Gas compressibility enhances and liquid viscosity damps out both temporal and spatial part of absolute instability growth rate. Although Weber number promotes the temporal growth rate of absolute instability, it has a dual effect of enhancing and inhibiting the spatial growth rate.
- OSTI ID:
- 357745
- Report Number(s):
- CONF-980213-; TRN: IM9932%%90
- Resource Relation:
- Conference: 1998 energy sources technology conference, Houston, TX (United States), Feb 1998; Other Information: PBD: 1998; Related Information: Is Part Of Proceedings of the 1998 ASME energy sources technology conference (ETCE`98); PB: [1170] p.
- Country of Publication:
- United States
- Language:
- English
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