Performance of Turbofan Engine Nacelle Design for Boeing 777X Using Computational Fluid Dynamics Analysis

The efficient design of turbofan engine nacelles is critical for enhancing aircraft performance and supporting sustainable aviation goals. This study investigates the aerodynamic and thermal performance of various nacelle configurations for the Boeing 777X GE9x engine, focusing on innovative cooling strategies and drag reduction. Using Computational Fluid Dynamics simulations, nacelle shapes of varying lengths (10 m and 5.5 m), including long and short nacelles with and without chevrons, as well as an optimized ultra-short nacelle, were analyzed under cruise conditions. Models were developed using MATLAB and SolidWorks, and simulations were performed in ANSYS Fluent. Results indicate that the long nacelle with chevrons provided the best overall thermal and aerodynamic performance among the conventional designs, reducing drag and block fuel consumption by 10.13%. However, the optimized ultra-short nacelle, developed using a hybrid NSGA-Non Dominated Sorting Genetic Algorithm II and fmincon- Find Minimum of Constrained optimization approach using MATLAB, achieved a significantly lower drag coefficient and reduced block fuel consumption by 80.13%. These findings demonstrate the potential of advanced nacelle designs to improve heat dissipation, reduce aerodynamic drag, and lower emissions, aligning with stringent EASA standards and contributing to sustainable aviation advancements.