Vorticity Generation Mechanism by Baroclinic Torque and Buoyancy Effect in a Boundary Region of Dual-Density Flow Field(Thermal Engineering)

In the current study, the turbulent cavitation flow around a marine propeller in a nonuniform wake is simulated with the shear stress transport (k−ω SST) turbulence model combining Zwart–Gerber–Belamri (ZGB) cavitation model. The predicted cavity evolution shows a fairly well agreement with the available experimental results. Important mechanisms of propeller cavitation flow, including side-entrant jet and cavitation-vortex interaction, are analyzed in this paper. Vorticity is found to be mainly located in cavitation regions and the propeller wake during propeller rotating. The unsteady behavior of cavitation and side-entrant jet can both promote local vorticity generation and flow unsteadiness. In addition, it is indicated with the relative vorticity transport equation that the stretching term plays a major role in vorticity transportation, while baroclinic torque and Coriolis force term mainly influence the vorticity distribution along the liquid-vapor interface.

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Micro-Gravity Experiment on a Baroclinic Torque Generated by 2D Vortex-Pair Penetration into a Binary-Density Stratified Planar Boundary(Thermal Engineering)

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series B ◽

10.1299/kikaib.76.762_319 ◽

2010 ◽

Vol 76 (762) ◽

pp. 319-325

Author(s):

Yojiro ISHINO ◽

Yu SAIKI ◽

Masayoshi KATAOKA ◽

Kosaku INABA ◽

Norio OHIWA

Keyword(s):

Vortex Pair ◽

Thermal Engineering ◽

Planar Boundary ◽

Baroclinic Torque ◽

Binary Density ◽

Micro Gravity

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Isothermal Flow Fields in a Research Combustor for Lean Blowout Studies

Volume 3: Coal, Biomass and Alternative Fuels; Combustion and Fuels; Oil and Gas Applications; Cycle Innovations ◽

10.1115/91-gt-037 ◽

1991 ◽

Author(s):

G. J. Sturgess ◽

S. P. Heneghan ◽

M. D. Vangsness ◽

D. R. Ballal ◽

A. L. Lesmerises

Keyword(s):

Flow Field ◽

Laser Doppler Anemometry ◽

Constant Density ◽

Undue Influence ◽

Optical Access ◽

Field Development ◽

Lean Blowout ◽

Primary Zone ◽

Density Flow ◽

Jet Behavior

A propane-fueled research combustor has been designed and developed to investigate lean blowouts in a simulated primary zone of the combustors for aircraft gas turbine engines. To better understand the flow development and to ensure that the special provisions in the combustor for optical access did not introduce undue influence, measurements of the velocity fields inside the combustor were made using laser Döppler anemometry. These measurements were made in isothermal, constant density flow to relate the combustor flow field development to known jet behavior and to backward-facing step experimental data in the literature. The major features of the flow field appear to be consistent with the expected behavior, and there is no evidence that the provision of optical access adversely affected the flows measured.

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