A note on the Galilean invariance of aerodynamic force theories in unsteady incompressible flows
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As a basic principle in classical mechanics, the Galilean invariance states that the force is the same in all inertial frames of reference. But this principle has not been properly addressed by most unsteady aerodynamic force theories, if the partial force contributed by a local flow structure is to be evaluated. In this note, we discuss the Galilean-invariance conditions of the partial force for several typical theories and numerically test what would happen if these conditions do not hold.
KeywordsGalilean invariance Aerodynamic force theory Unsteady flow Flow diagnoses
This work was supported by the National Natural Science Foundation of China (Grant 11472016).
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