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Ying, Susan X.

Publications and source records attributed to Ying, Susan X..

Prediction of High-Lift Flows using Turbulent Closure Models

The flow over two different multi-element airfoil configurations is computed using linear eddy viscosity turbulence models and a nonlinear explicit algebraic stress model. A subset of recently-measured transition locations using hot film on a McDonnell Douglas configuration is presented, and the effect of transition location on the computed solutions is explored. Deficiencies in wake profile computations are found to be attributable in large part to poor boundary layer prediction on the generating element, and not necessarily inadequate turbulence modeling in the wake. Using measured transition locations for the main element improves the prediction of its boundary layer thickness, skin friction, and wake profile shape. However, using measured transition locations on the slat still yields poor slat wake predictions. The computation of the slat flow field represents a key roadblock to successful predictions of multi-element flows. In general, the nonlinear explicit algebraic stress turbulence model gives very similar results to the linear eddy viscosity models.

Rumsey, Christopher L.↗

A numerical study of three-dimensional separated flow past a hemisphere cylinder

Separated and vortical flow about a hemisphere-cylinder body has been investigated. An algorithm featuring two implicit factors, and partial flux splitting has been used to solve the thin-layer Navier-Stokes equations. In analyzing the complex flow patterns, experimental data and topological concepts are used to complement the numerical results in interpreting the surface-flow patterns as well as the flowfield structures. Basic issues concerning the three-dimensional separation characteristics and the leeward vortical structures are examined.

Ying, Susan X.↗