Experimental assessment of PIV/PTV-based pressure reconstruction techniques applied to a low-speed base flow

Quantification of surface pressure is critical for the efficient design of aerospace structures. One way of measuring pressure is PIV/PTV-based pressure reconstruction [1]. In this approach, PIV/PTV data are used to determine the material acceleration and subsequently pressure via the momentum equation. In recent years, the technique has become increasingly feasible and appealing due to the development of (time-resolved) volumetric diagnostic capabilities, such as tomographic PIV [2] and Lagrangian particle tracking [3]. The performance of a variety of state-of-the-art techniques was recently assessed for the case of a transonic base flow within the collaborative European framework programs 'NIOPLEX' [4]. Since the NIOPLEX test case considers a simulated experiment, it does not necessarily demonstrate the actual capabilities of PIV/PTV-based pressure reconstruction techniques for realistic measurement conditions.
The present study overcomes this limitation by reconstructing pressure from actual PIV/PTV measurements of a flow that is similar to the NIOPLEX test case, i.e. an axisymmetric step albeit in a low-speed flow, facilitating comparison. Reference measurements are obtained using microphones and static pressure sensors to provide a source for comparison