Aerodynamic Development of Solar Car Considering Actual Flow Characteristics

Masato Ogawa･Takamasa Ninomiya･Kota Fukuda (Tokai University)･Hiroshi Tanaka･Hiromune Kanamori (Toyota Systems)･Kouhei Sagawa･Hideki Kimura (Tokai University)

Tokai University participated in many world solar car challenges. Top teams carried out aerodynamic development the state-of-the-art CFD technologies. The consideration of actual flow characteristics is crucial for the aerodynamic development of solar cars since the challenges are held in public roads. Tokai university solar car team has carried out aerodynamic development considering actual flow characteristics. In this presentation, outline of our aerodynamic development based on actual flow characteristics will be introduced.

Effect of slant angle and Reynolds number on regimes of flow around Ahmed body – difference with turbulence models

Shunta Fukuoka･Itsuhei Kohri･Suguru Shiratori (Tokyo City University)

Regimes and drag coefficient (CD) of flow around the Ahmed body may drastically change depending on the slant angle. To clarify the range where these steep CD changes take place, a series of CFD simulations is carried out using RANS turbulence models. The range of Reynolds number and slant angle for flow regime change is found to be different depending on the turbulence model used.

Aerodynamics shape optimization based on VAE and PINN - hybrid SDF and point-cloud method

Kaho Hikita･Suguru Shiratori (Tokyo City University)

In aerodynamic shape optimization, conventional methods, which require re-meshing, take huge computational cost. Our research group has proposed mesh-free approach, where the shape is parameterized by latent space based on VAE and aerodynamic drag is evaluated by PINNs. In this study, we propose a new shape representation using hybrid of SDF and point-clouds. Validations are conducted for two-dimensional airfoils.

A Comparative Study of Airflow Around a Vehicle During On-Road Driving and on a Chassis Dynamometer

Daisuke Kawano (Osaka Sangyo University)･Souma Iiboshi (Osaka Sangyo University (Currently, Daihatsu Motor))･Kazuki Aoyama (Osaka Sangyo University)･Toshimichi Takahashi (Meidensha)

Since airflow around a vehicle significantly affects its performance, chassis dynamometers need to reproduce airflow during on-road driving. In this study, airflow on a chassis dynamometer was compared with that during on-road driving by simultaneously measuring airflow velocity at multiple points around the vehicle. In addition, the factors causing the differences in these airflows were analyzed using CFD.