Multi-disciplinary framework for propeller blade design

Improved propeller designs are necessary to ensure an eco-friendly and resource-saving operation. The shape optimization of propellers involves different disciplines, which include the aerodynamics and the structural characteristics of the propeller. The requirements of the individual disciplines for the propeller design are contradictory and compromises must be made. To deal with this complex optimization task, a modular multi-disciplinary optimization framework is developed. The framework is based on a Python control script, which invokes the individual analysis modules. Within the framework, a blade element momentum theory approach for the aerodynamic analysis and a finite element method for the structural analysis are used. This allows for an efficient calculation of various designs. In a first step, a pure aerodynamic optimization is conducted. In a second step, structural constraints in form of the permissible material stress and the propeller blade tip deflection are considered. The results are compared to a design method, which calculates the blade shape for minimal induced losses.