Founded in 2009, Poly eRacing is a Technical Student Club from Polytechnique Montréal, Canada that designs and manufactures a 100% electric single-seat race car in order to compete at international events and promote low-carbon means of transportation. In 2016, the team competed at two competitions: Formula North (Barrie, Ontario, Canada) and Formula SAE Lincoln (Lincoln, Nebraska, USA). Poly eRacing is proud to have won a third place on the podium at those two events.
With over 40 multi-talented, motivated members on the team, Poly eRacing is now trying to push even further its competitiveness by working on improving every subsystem of its next prototype and by better understanding how these subsystems interact together. This is where NUMECA INTERNATIONAL becomes crucial.
One of the many things Poly eRacing has to study, is how aerodynamics affects the car and its overall performance and maneuverability. HEXPRESS™/Hybrid allows the team to generate high-quality meshes with the refinement settings it wants, which are then used by the aerodynamics specialists to conduct the CFD simulations required to take the best design decisions possible. For instance, it is primordial for the suspension team to know the amplitude of the aerodynamic loads (downforce and drag) at several velocities, and where those loads are applied in order to wisely design the car’s suspension. It is also very important to determine the amount of drag generated at any given speed, so that the team can calculate how much energy is required to complete the endurance event. This helps to optimize the accumulator container by making it just the right size, saving the car a lot of unnecessary mass.
These are just simple examples, but CFD simulations are used by the team in a myriad of other contexts. Poly eRacing has decided to use NUMECA INTERNATIONAL’s HEXPRESS™/Hybrid to generate its meshes, which are perhaps the most important component of any numerical simulation.
Left: The geometry of the car visualized with HEXPRESS™/View - Right: The mesh generated with HEXPRESS™/Hybrid
The team’s aerodynamics specialists use HEXPRESS™/Hybrid’s graphic interface to select and name the main regions and facets of the studied geometry. Then, they run a customized configuration file on one of the university’s supercomputer to generate the mesh that has the characteristics it needs and the right refinements at the right places.
The team usually generates a surface mesh (.SPB) before generating the tridimensional one they will be using for their simulation (.CGNS) whenever a parameter is changed. This enables them to visualize the mesh before using it, which helps them assess its quality. When visualization alone is not enough, it is always possible for them to consult the mesh generation report, created by default whenever a new mesh is made.
In conclusion, NUMECA INTERNATIONAL’s HEXPRESS™/Hybrid is a very powerful tool that Poly eRacing has used and will continue using in its attempt to become even more competitive, and to – who knows? – be part one day of the world’s top three SAE Electric teams.
AUTHOR: Paul-Étienne Carrier is the Aerodynamics Project Manager of Poly eRacing. Poly eRacing is a Formula SAE Electric, team founded in 2009.