Simple Approach for Modeling Fan Systems with a Computational-Fluid-Dynamics-Based Body-Force Model

This paper presents the use of a conventional computational-fluid-dynamics-based throughflow method to model the effects of a bypass fan in a propulsion system (for example, nacelle) under the restriction that information about the fan blade geometry is unavailable. Instead, the fan body-force model requires fan-performance data at different operating points as input. A simple implementation strategy is proposed to achieve this goal and extend the use of the body-force model to off-design operating conditions where fan-performance data are limited. This approach has been validated with axisymmetric calculations on three blade rows to demonstrate its capability at off-design conditions. The tool may be very useful to nacelle designers, who often have limited information about fan-performance data from engine suppliers.