Optimization of Active Grille Shutters Operation for Increased Fuel Economy

Ales Alajbegovic, EXA Corporation

CHALLENGE - The airflow into a motor vehicle underhood cools essential components, yet this underhood flow increases drag and can significantly reduce fuel economy, especially at high travelling speeds. Active grille shutters (AGS) can be used to reduce drag penalty and raise fuel economy, which is the scope of this study.

SOLUTION - In this study, an EV12 AGS design is optimized using optimization software modeFRONTIER. Five design variables are defined (ambient temperature, vehicle speed, AGS upper and lower closure, fan speed). 23 simulations for characterization​ are run. Aero-thermal simulations are performed in Exa Corporation's PowerFLOW.

BENEFITS - The optimized AGS operation shows a 1.5% improvement in vehicle fuel economy. This approach using a modeFRONTIER workflow can be applied to other components such as fan speed control and charge air cooler and condenser. Furthermore, dynamic effects to drive cycle can be added: thermal transient and heat-up/cool-down time .