This article presents a method for predicting contra rotating propellers individual and total performance which is fast and robust enough to be used in performance engine cycle and engine subsystems detailed design. The method is based on the use of single propeller maps and models mutual induced velocities thanks to one-dimensional theories. These velocities are responsible for interferences between propellers. This article goes through the assumptions on which stands the proposed method and shows that it is relevant compared against more complex methods such as lifting line theory and definitively provides a valuable easy-to-enforce preliminary design tool for open rotor propulsor controls sizing.

This article provides an overview on the challenges related to the prediction of propellers performance at preliminary design stage, ranging from numerical stability to simplicity required for being integrated into engine cycle models. After a description of the usual approach to propeller performance based on maps, and a discussion on its limitations, innovative methods are proposed, lying on the identification of losses trends combined with the use of propeller characteristic operating points over the whole usable area. These innovative approaches significantly reduce the number of required simulations or test cell points to be able to describe the full propeller range of operation, adding physics to the mathematical approach usually considered for turbomachinery component maps elaboration. Accuracy and stability of the considered approaches are discussed, along with an assessment of the required effort to set them up.