Acta Mechanica Sinica

, Volume 35, Issue 6, pp 1150–1154 | Cite as

A note on the Galilean invariance of aerodynamic force theories in unsteady incompressible flows

  • An-Kang Gao
  • Jiezhi WuEmail author
Research Paper


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.


Galilean 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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Copyright information

© The Chinese Society of Theoretical and Applied Mechanics and Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.State Key Laboratory for Turbulence and Complex Systems, College of EngineeringPeking UniversityBeijingChina

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