Onroak Automotive was selected by the ACO – Automobile Club de l’Ouest -, the FIA – Fédération Internationale de l’Automobile – and the IMSA – International MotorSports Association – as one of the four constructors of 2017 LM P2 chassis. The French company is pursuing the design process of its latest model, which is called the Ligier JS P217:
“JS” is the continuity of the cars built by Guy Ligier whose name always included the initials of his late friend, Jo Schlesser.
“P217” as a reference to the LM P2 category, and the 2017 year.
Directed by Nicolas Clémençon, the Onroak Automotive design department is starting the aerodynamic validation phase in the wind tunnel this week. This test completes the studies and CFD calculations carried out in partnership with EXA, a specialist in digital simulation. The collaboration between the two companies has already borne fruit with the Ligier JS P3.
Three engineers from the design office and two technicians from the Le Mans workshops have gone to the RUAG wind tunnel in Switzerland in which the French constructor’s previous models’ designs have been studied and validated.
A 40 per cent scale model has been made on a partial carbon base, in particular for the shell and the flat bottom, and the development parts have been produced by stereolithography, a rapid prototyping system using polymer resin. Some 80 points have been picked out on the model to measure pressure for analysis.
The team is using a moving floor and air flow speed of 50m/sec. The tunnel is equipped with a boundary layer suction system on the front axle. A smoke generator is also available for the team to provide visual analysis of the air flow.
These tests will help the design department engineers to validate the best choices from among the aerodynamic solutions already selected.
Nicolas Clémençon, design office manager – chief designer: “The validation phase of the aerodynamics is always crucial in the design of a new sports prototype. The CFD studies and the work in the wind tunnel complement each other very well and enable us to analyse the maximum amount of data thanks to which we can validate optimal solutions. We’re lucky to be working with EXA for the CFD phase and with the RUAG wind tunnel: their professionalism and the quality of their services are a guarantee of the efficiency and safety of our cars.”