|Optimal Shape of Blunt Device for High Speed Vehicle
Joo-Hyun Rho, Seongmin Jeong and Kyuhong Kim
International Journal of Aeronautical and Space Sicences, vol. 17, no. 3, pp.285-295, 2016
Abstract : A contact strip shape of a high speed train pantograph system was optimized with CFD to increase the aerodynamic
performance and stability of contact force, and the results were validated by a wind tunnel test. For design of the optimal
contact strip shape, a Kriging model and genetic algorithm were used to ensure the global search of the optimal point and
reduce the computational cost. To enhance the performance and robustness of the contact strip for high speed pantograph,
the drag coefficient and the fluctuation of the lift coefficient along the angle of attack were selected as design objectives.
Aerodynamic forces were measured by a load cell and HWA (Hot Wire Anemometer) was used to measure the Strouhal
number of wake flow. PIV (Particle Image Velocimetry) was adopted to visualize the flow fields. The optimized contact strip
shape was shown a lower drag with smaller fluctuation of vertical lift force than the general shaped contact strip. And the
acoustic noise source strength of the optimized contact strip was also reduced. Finally, the reduction amount of drag and noise
was assessed when the optimized contact strip was applied to three dimensional pantograph system.
Keyword : High speed train, Pantograph contact strip, Design optimization, Wind tunnel experiment, Aerodynamic performance, Acoustic noise source.