Flow adaptive aerodynamic probe for turbomachinery flows

ETH, Swiss Federal Institute of Technology, Turbomachinery Laboratory, Zurich, Switzerland

^* Christian Lenherr: christian.lenherr@ethz.ch
^† Martin Oschwald: martin.oschwald@sfckoenig.com
^‡ Anestis I. Kalfas: akalfas@auth.gr
^§ Reza S. Abhari: abhari@lec.mavt.ethz.ch

Abstract

In order to enable turbomachinery research to obtain data highly resolved in space and time, a novel flow adaptive aerodynamic probe concept has been developed and presented in this paper. The algorithm selects the measurement positions of the probe automatically and therefore provides higher measurement fidelity compared to traditional methods. The development of the adaptive algorithm has been done in several steps. First an automatic 1Dtraversing algorithm has been developed. The following steps dealt with the subject of a 2D adaptive flow concept development, whereas primarily visual programming language-computer package simulations of the new 2D algorithm have been done based on data from previous test series at the Turbomachinery Laboratory. The new 2D traversing algorithm is fully selfcontrolled and requires minimal input such as blade count and hub and tip diameters. Furthermore, areas of interest (e.g. secondary flows, wake) are detected automatically and higher measuring point resolutions are ensured in these regions. After the successful simulations, the intelligent 2D algorithm has been adapted to an object oriented programming environment used for automated data acquisition and reduction. An evaluation of the flow adaptive aerodynamic flow concept has been done on a pressure turbine facility by means of a steady pneumatic probe. The measurement results show that the new 2D algorithm has the potential to detect new flow phenomena. In contrast to traditional algorithms, which in case of a possible enhancement demand a knowledge of the position of interesting areas such as the wake and vortical structures before starting the measurement, the new algorithm detects the right areas and enhances the resolution fully self controlled in these areas. Furthermore, the new 2D flow adaptive probe concept shows a significant improvement regarding the needed time for one measurement.