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Dynamic wind-tunnel tests of a simplified passenger car model were conducted using a two-degree-of-freedom model shaker. Time-resolved aerodynamic loads were derived from a built-in six-component balance and other sensors while the model underwent sinusoidal heaving and pitching motions at frequencies up to 8 Hz. The experimental results showed that frequency-dependent gains and phase differences between the model height/angle and the aerodynamic loads are in close agreement with those predicted by large-eddy simulation (LES) using an arbitrary Lagrangian-Eulerian (ALE) method. Based on these findings, transient aerodynamic loads associated with lateral motions were also estimated by LES analysis. Based on the above results, a full-unsteady aerodynamic load model was then derived in the form of a linear transfer function. The force and moment fluctuations associated with the vertical and lateral motions are well described by the full-unsteady aerodynamic load model.

In the preliminary design phase of an aircraft, handbook methods are used to size the aircraft and to predict its aerodynamic characteristics and flight performances. For a new twin-boom pusher UAV a systematic comparison of theoretical predictions and wind tunnel test data is performed. It is shown that although performance and stability parameters are generally well predicted important deviations can occur if the specific airplane configuration is not taken into account in a sufficiently accurate manner. This is illustrated using results from pitching moment estimates for different tail configurations.

Race cars undergo very quick ride height changes on the track, which are induced by breaking, acceleration, cornering, as well as bumps on the track. It has recently been shown in wind tunnel tests that these quick changes in model attitude can lead to astonishingly large hysteresis effects on the aerodynamic coefficients. In order to verify whether such effects may be relevant to the overall performance of a car, aerodynamic data from wind tunnel tests with a moving model was fed into a vehicle dynamics simulation program. Relevant changes in estimated car performance on straight as well as on curved tracks are reported.