Point and planar LIF for velocity-concentration correlations in a jet in cross flow

A new model is developed to predict laterally-averaged film cooling. At the injection location, the near-hole region is leapt over and the injectant is distributed according to an existing jet in cross flow model and experimental data. The subsequent dispersion of the injectant is simulated to reflect the augmented mixing and the 3-dimensionality of the flow field. The new model is calibrated to predict effectiveness and heat transfer using the experimental data bases of Schmidt et al. (1994), Sen et al. (1994), Kohli et al. (1994), and Sinha et al. (1991). The geometries include injection angles of 35° and 55° with compound angles of 0° and 60° and hole spacings of 3 and 6 diameters. The new model yields improved effectiveness predictions over previous 2-D models.

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Large Eddy Simulation of Turbulent Reacting Jet in Cross Flow with Adaptive Mesh Refinement

52nd Aerospace Sciences Meeting ◽

10.2514/6.2014-0825 ◽

2014 ◽

Cited By ~ 1

Author(s):

Balaji Muralidharan ◽

Suresh Menon

Keyword(s):

Large Eddy Simulation ◽

Adaptive Mesh Refinement ◽

Mesh Refinement ◽

Cross Flow ◽

Adaptive Mesh ◽

Eddy Simulation ◽

Jet In Cross Flow ◽

Large Eddy

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Direct Numerical Simulation of Single and Multiple Square Jets in Cross-Flow

Journal of Fluids Engineering ◽

10.1115/1.4003588 ◽

2011 ◽

Vol 133 (3) ◽

Cited By ~ 7

Author(s):

Y. Yao ◽

M. Maidi

Keyword(s):

Cross Flow ◽

Vortex Pair ◽

Flow Structures ◽

Computational Domain ◽

Freestream Velocity ◽

Adjacent Edge ◽

Vortex Pairs ◽

Jet In Cross Flow ◽

Edge Distance ◽

Square Jets

Direct numerical simulations (DNSs) have been carried out for single and multiple square jets issuing normally into a cross-flow, with the primary aim of studying the flow structures and interaction mechanisms associated with the jet in cross-flow (JICF) problems. The single JICF configuration follows a similar study previously done by Sau et al. (2004, Phys. Rev. E, 69, p. 066302) and the multiple JICF configurations are arranged side-by-side in the spanwise direction with a jet-to-jet adjacent edge distance (H) for the twin-jet case and an additional third jet downstream along the centerline with a jet-to-jet adjacent edge distance (L) for the triple-jet case. Simulations are performed for two twin-jet cases with H=1D,2D, respectively, and for one triple-jet case with H=1D, L=2D, where D is the jet exit width. Flow conditions similar to Sau et al. are considered, i.e., the jet to the cross-flow velocity ratio R=2.5 and the Reynolds number 225, based on the freestream velocity and the jet exit width. For the single jet in cross-flow, the vortical structures from our DNS are in good qualitative agreement with the findings of Sau et al. For the side-by-side twin-jet configuration, results have shown that the merging process of the two initially separated counter-rotating vortex pairs (CRVPs) from each jet hole exit is strongly dependent on the jet-to-jet adjacent edge distance H with earlier merging observed for the case H=1D. Downstream, the flow is dominated by a larger CRVP structure, accompanied by a smaller inner vortex pair. The inner vortex pair is found not to survive in the far-field as it rapidly dissipates before exiting the computational domain. These observations are in good agreement with the experimental findings in the literature. Simulations of the triple-jet in cross-flow case have shown some complicated jet-jet and jet-cross-flow interactions with three vortex pairs observed downstream, significantly different from that seen in the twin-jet cases. The evidence of these flow structures and interaction characteristics could provide a valuable reference database for future in-depth flow physics studies of laboratory experimental and numerical investigations.

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