Deriving forces from 2D velocity field measurements

摘要: We discuss how to derive a force or density from measured velocity field. The first part focuses on the integral fluid exerts body, e.g. lift and drag an airfoil. Obtaining correct pressure is crucial; however, it cannot be within flow non-intrusively. Using numerical experimental test cases, we compare accuracy achievable with three methods: reconstruction fields via (1) differential momentum equation, (2) Poisson furthermore, (3) Noca’s equation [Noca, JFS 13(5), 1999], which does not require explicitly. latter gives best results for lift, whereas second approach should used drag. deals obtaining distribution of body generated by actuator. stream function ansatz, obtain Laplace that allows us compute solenoidal distribution; irrotational lost. Furthermore, wall must known. validate this using data jet in rectangular box, driven fictitious, force. Reconstructing yields error less than 10−2 most domain.