Unsteady boundary layer transition detection by automated analysis of hot film data

Abstract

Serveral automated algorithms are implemented to examine the transitional behavior of the pitching airfoil DSA-9A. The state of the art method to detect unsteady boundary layer transition with experimental hot film data is a manual approach. Therefore to reduce the investigation time an improve the data quality an automated detection has been created. In the most cases the computation time of the unsteady boundary layer detection is almost two orders of magnitude faster compared to manual extraction. Several algorithms will be discussed in this paper of which an algorithm utilizing the skewness produces the best results in a robust implementation.