Measurements and simulations are presented of the flow past a tailplane research
airfoil which is designed to show a mixed leading-edge trai领-edge stall
behaviour. The numerical simulations were carried out with two flow solvers that
introduce transition prediction based on linear stability theory to RANS
simulations for cases involving laminar separation bubbles. One of the methods
computes transition locations across laminar separation bubbles whereas the
other assumes transition onset where laminar separations occur. For validation of
the numerical methods an extensive measurement campaign has been carried out.
It is shown, that the methodology mentioned first can simulate the size of laminar
separation bubbles for angles of attack up to where the separation bubble and the
turbulent separation at the trai领 edge are well behaved and steady in the mean.
With trai领 edge separation involved, the success of the new numerical
procedure relies on the diligent choice of a turbulence model. Finally, for flows
with increased unsteady behaviour of both, separation bubble and turbulent
separation, which were observed at higher angles of attack in the experiment
between maximum lift and leading-edge stall, steady state prediction methods for
transition can no longer be applied and time-accurate methods have to be
developed in a further step. 德国LaVision PIV/PLIF粒子成像测速场仪
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