Design and Experimental Characterization of a Gust-Generator Concept with Rotating-Slotted Cylinders in the Low-Speed Wind Tunnel DNW-NWB

Abstract

The present study focuses on the design of a gust generator based on stationary airfoils coupled with downstream rotating, slotted cylinders, specifically configured for the low-speed wind tunnel DNW-NWB. Owing to the technical requirements imposed by the test facility and the desired gust characteristics, this particular gust-generator concept is chosen. Numerical computations for both wake-flow characteristics and structural properties are performed, so as to explore various design parameters. In a subsequent step, an experimental test campaign is conducted, in which the gust generator wake flow is characterized using an unsteady fast-response 5-hole probe. The results reveal that highly periodic gust flows are induced by the gust generator, with gust amplitudes that are sufficiently large for investigating the gust response of flexible aircraft structures, e.g., wings. Besides, the gust frequency is directly proportional to the cylinders rotational speed, whether a continuous or discrete gust is generated. Future work is dedicated towards further enhancing the present gust generator, including - but not limited to - the motor controls that drive the rotating cylinders.