Entwicklung eines Programms zur Berechnung von instationär nicht planar angeströmten Rotoren

Abstract

The concept of a flexible program for the design and analysis of rotors with different inflow conditions with the possibility to include program extensions easily was envisioned and implemented. All parts of the program can access the object-oriented implementation of a rotor parameter storage structure to get inputs for their respective calculations. The following aspects of this concept has been implemented in MATLAB: The Design of a rotor for design parameters is possible with use of the Blade-Element-Momentum-Method (BEM) by Adkins. A rotor can be analyzed using the same BEM Method. This analysis can be done for different operating points and summarized to a performance map. This performance map can incorporate different blade angles of a variable pitch propeller and give the best blade angle for each operating point. The wake geometry of an analyzed rotor can be calculated using a Wake-Relaxation method with the use of the Biot-Savart-Law. In order to use an existing rotor with the Tool, a toolchain has been established for scanning the rotor, extracting the profiles, calculating the profile-polars for each bladesection and analyzing the rotor in the program. Empirical formulas to extend the profile-polars to angles of attack of about ±140� have been included For use cases where the angle of attack exceeds the commonly used regions.