September 8, 2020
Each year, the Spartan Racing Formula SAE team (Spartan Racing) at San José State University designs, builds, and tests a new Formula style race car based on regulations and standards similar to those imposed on professional motorsport teams. This competition immerses students in an environment that parallels a competitive work environment and professional race team.
For the 2020 season, Spartan Racing’s goal was to efficiently design and simulate their Formula SAE race car’s aerodynamics, with a focus on modeling radiators, restoring moment, and cornering simulation. The team found a way to increase the simulation quality of their car using STAR-CCM+ but discovered that the simulations would take over a day to run on the computers provided. Furthermore, the design of the radiators and sidepod required high-fidelity meshing to resolve the flow downstream of the front tire, which substantially increased the computational time. These challenges prompted the team to look into High Performance Computing (HPC) providers, ultimately choosing Nimbix.
“With the JARVICE HPC platform and higher fidelity meshes, we were able to run more design iterations than if we were to have run on our computers. This allowed us to achieve a greater understanding of our car’s performance as well as bridging the gap between the real car’s values and the values of our simulations,” said Nathaniel Irpan, Spartan Racing Aero Team Lead.
Irpan added, “For example, with the use of HPC, we were able to develop a cornering simulation that closely replicates the car’s performance in one of FSAE’s dynamic events, Skid Pad, which has never been done before in the history of our team.” Understanding how the car reacted in a real cornering situation the team used that information to develop the car’s aero package further.
“Having access to HPC allowed us to assess various sidepod designs and optimize them within the constraints that we had,” said YongMoon Won, Spartan Racing Team CFD Lead. “We were also able to design radiators that showed a 50% increase in air mass flow rate, which is critical to keeping the engine cool”.
Further, the HPC capability meant that when yawing the car, a sensitive simulation case, Spartan Racing could run high fidelity meshes to capture the vehicle's restoring moment. The restoring moment number’s sensitivity can be affected by the simulation quality, so high cell count simulations were ideal and easily accomplished on the Nimbix Cloud.
Using Siemens STAR-CCM+ on the Nimbix Cloud, the team was more confident in the design regarding the downforce and drag values from the simulation. According to Irpan, “This is because, with higher fidelity meshing, we can more accurately predict flow separation whereas, with a lower resolution mesh, we might not have seen flow separation.” Spartan Racing was able to try different meshing strategies quickly, so they didn’t have to wait long to see if it worked. “The combination of STAR-CCM+ on the Nimbix Cloud also gave us greater confidence in the aerodynamic package design, as we were able to see that the air is propagating downstream of the car more accurately and that the radiators’ airflow cooling capacity can change the design in the future if necessary.”, Irpan added.
Even with some huge milestones under Spartan Racting’s belt, they are met with challenges with the cancelation of events due to COVID-19. Despite this, team members continue to enjoy the invaluable educational experience and are keeping the world informed of their latest accomplishments on their website and social media.