Propeller Design Within the Overall Configuration of a Near-Space Airship

High-efficiency propeller design is essential for reducing the total mass of near-space airships under low-Reynolds-number conditions. This study optimizes the overall design parameters of near-space airships by integrating an efficient engineering propeller design method based on characteristic blade elements. This overall configuration yields results close to those obtained from single-objective optimization of the propellers. Through analysis of the overall configuration, it is evident that there is limited room for optimization in terms of propeller efficiency improvement. Therefore, a variable-speed strategy that accounts for different flight speeds during day and night is proposed. The variable-speed strategy achieves a 29.6% reduction in total airship mass compared to the constant-speed baseline. These findings verify that optimizing flight speeds and propeller efficiency is effective for achieving lightweight airship designs.