Astigmatism Particle Tracking Velocimetry for Macroscopic Flows

Astigmatism Particle Tracking Velocimetry (APTV) is a three-dimensional flow measurement technique. It requires only a single camera and is therefore best suited for measurement domains with limited optical access, such as compressor and combustion research. The z-component of the spatial particle position is coded in the geometry of its particle image. In order to prove the feasibility of APTV to measure macroscopic air flows, an accuracy analysis using a pinhole matrix (pinhole diameter of 1.1±0.1 µm) is carried out. Two different optical setups with different measurement depths (20-100 mm) are investigated. The relative measurement error lies in the range of 0.34-0.46 % of the measurement depth. Altogether APTV allows for accurate volumetric velocity measurements in macroscopic air flows. 1