Image Based Measurement Techniques of Increased Complexity for Industrial Propeller Flow Investigations

Abstract

The image based measurement techniques Background Oriented Schlieren (BOS) and Particle Image Velocimetry (PIV) are particularly useful for the investigation of propeller flow. Dedicated measurements are performed of increasing complexity. Initial in-vestigations are performed with BOS and stereoscopic PIV on a single sting propeller. The model complexity is then increased to half-model for the investigation of propeller wing in-terference at thrust reverse and high-lift conditions (for positive and zero thrust). At each stage the techniques can be used as a validation for computational methods. BOS can readily be applied without too much costs and preparation. The utilization of stereoscopic and mono PIV set-ups requires more preparation. It is shown that BOS and PIV are indispensable tools for instantaneous propeller flow investigations. Furthermore it is stated that PIV is an invaluable tool for numerical validation purposes.