Nonintrusive determination of aerodynamic pressure and loads from PIV velocity data (Invited)

Traditionally in aerospace research, pressure is measured with pressure probes or wall-mounted sensors, while integral loads are obtained by means of balance systems. Recent years have seen the emerging and development of an alternative approach, which exploits Particle Image Velocimetry (PIV) data as a source for the nonintrusive determination of pressure fields and fluid-dynamic loads. The essential working principle underlying this approach is that, through invoking the momentum equation, the pressure gradient can be derived from the measured flow acceleration, yielding the pressure field upon spatial integration. Important potential benefits of this approach are, amongst others, that full field pressure data can be obtained and that no instrumentation is required for surface pressure mapping. In addition, it permits velocity and pressure data to be acquired simultaneously, which is relevant in, for example, aero-elastic and aero-acoustic areas. The presentation will address the operating principles and implementation of this method, as well as discuss some applications in areas that are of relevance to the aerospace technology domain.