Testing Active Rotor Control Applications using DLR's Multiple Swashplate Control System in the LLF of DNW

Abstract

In the context of the joint research project advanced swashplate concepts within the nationally funded aeronautical research programm LuFo V-1, DLR’s multiple swashplate control system has successfully completed its first wind tunnel tests in DNW’s large low-speed facility. The main goal of the wind tunnel tests was to examine the effectiveness of several individual blade control strategies regarding noise, vibration and power reduction at different wind speeds and flight attitudes using highly instrumented Bo105-type model rotor blades as well as a newly manufactured set of model rotor blades with a more modern blade planform and profiles. The results of these tests, which for the first time included 2/rev higher harmonic control and tip path plane splitting without using actuators in the rotating frame, are a valuable addition to the data gathered from the HART- and HART II campaigns and additionally provide the opportunity to directly compare the performance of two different generations of rotor blades under otherwise identical test conditions. This paper provides an initial overview over the test setup of the rotor test rig including the multiple swashplate control system, the different measurement systems used in the wind tunnel tests, the test procedures as well as the specific blade control strategies to reach the goals. Selected first results are presented to provide an initial overview over the measurements taken and an outlook on broader, more in-depth analyses available after further data evaluation.