Image measurement of flow field using physics-based dynamic model

The PIV technique is generalized from the viewpoint of the identification problem of a flow field. The process of obtaining a velocity distribution as an image measurement can be considered as a parametrization problem of a dynamical system. In almost all conventional techniques, the velocity is evaluated as the parameters in a dynamical system using a linear model without physics. These methods always give some spurious velocity vectors in the case of shear flow or vortex how, and in the region where the tracer particles are scarce. A new PIV technique based on physics is proposed. The obtained velocity field satisfies the governing equation of the fluid. It is possible that not only the velocity but also the pressure is measured, using the Navier-Stokes equations for the dynamic model. The results of jet flow, cavity flow and flow around a waving airfoil demonstrate the effectiveness of this method.