Polyjoule is a French team composed of students from two schools: the Graduate School of Engineering at the University of Nantes and La Joliverie Technique High School. The Polyjoule team competes in the hydrogen category at Shell Eco-marathon Europe and the Educ Eco Challenge in France essentially.
There are three groups of students, each focusing on a different aspect of the car. La Joliverie High School is concentrating on the mechanical issues of the projects, and they are able to size every part of the car to get the perfect result. The Thermal and Energy Sciences students from Polytech Nantes have to develop and build the fuel cell that will produce the necessary energy to propel the vehicle. Finally, the Electrical Engineering students from Polytech Nantes have to improve the electronics that manage every part and every function of the car.
This collaboration among skill sets led the team to achieve a world record at Shell Eco-marathon in 2011 in Lausitz, Germany, reaching 5.136 kilometers with the energetic equivalent of one gasoline liter in the Hydrogen Prototype category.
In 2012, the team achieved a new world record, in the South of France at the Educ Eco Challenge, beating any category world record in the race and reaching 10.017 kilometers with the energetic equivalent of a gasoline liter, powered by an electrical battery.
That’s it for the story of Polyjoule, a team that has achieved two world records and contributed to the happiness of many students— but the 2012-2013 season is around the corner.
New Season, New Car, New Category
After seven years competing in Eco-marathon’s Prototype category, the whole team decided to compete in the Urban Concept category this year, still with hydrogen. This presented a new challenge for the students, assisted by their teachers, who are responsible of the continuity of the project. The idea was born three years ago, and the new vehicle named CityJoule was inaugurated in March 2013.
After many wins at Shell Eco-marathon and the Educ Eco Challenge in the Prototype category, the team wanted to be closer to today’s well-known cars. The Urban Concept category proposed by both challenges was a good way to take part to the wishes.
But the first step was wondering was to know what kind of car we wanted to build. Will it be a simple vehicle that will be able to compete at challenges at the end of the year, or will it be a perfect vehicle that will take longer, but be the most energetically efficient, the best on the tracks ?
We did not wait to get the answer. We want to win in the Urban Concept category, so we want to have the most perfect vehicle of the category, even if it will take years.
The team first decided to have many partnerships with French companies, especially next to the city of Nantes. Nothing is possible for a student association without partners.
The next step was to design the vehicle, helped by Daniel Pasquini, who designed the more aerodynamic car in 1963 for the race Les 24 Heures du Mans. He helped the team get the most aerodynamic car. The inspiration was based on a drop of water, and on Daniel’s experience.
The FMC company from Brittany built the car based on 3D software models with the help of the Engineering School Centrale Nantes and HES in Switzerland.
The whole car was built with carbon fiber to make it lighter. Every part has been conceived to be the lightest and the most drag-resistant, and the team never forgets about the aesthetic aspect!
After that, the team from Thermal and Energy Sciences has to think about the propulsion: one fuel cell? two? series arrangement? parallel? Many tests were done at Polytech Nantes this summer, and we decided to use two fuel cells, one for each rear wheel.
The rest of the work was a little bit hard for everyone: some had to put together all the car parts, others had to build fuel cells to have a stock for the challenges, and Electrical Engineering students had to work out electronic systems.
All was ready, the result is just.. awesome !
The aerodynamic coefficient of the vehicle is simply the lowest in the world, less than 0.1! It has been proved at the wind tunnel of CSTB, in Nantes.
Everything has been designed to be optimum, and to match with the rules of the challenges.
The car is able to stop his race in three meters with an initial speed of over 30km/h. The suspensions are just perfectly settled to be sure that every wheel is in contact with the floor, but with least amount of energy lost via the suspension system.
The shade of blue used is “Bleu France” (“French Blue”) used between 1960 and 1970 for French cars participating in the 24 Hours of Le Mans, which were the most successful in terms of aerodynamics at the time.
This year the team will be participating in two challenges: Educ Eco Challenge in France from May 8 to 11 and Shell Eco-marathon in Rotterdam from May 15 to 19, both in the Hydrogen category. The goal is to show to every team that anything is possible with time, partners, and passion.
The whole team is at the starting block, spending nights and days to prepare the car and the people behind it.
Even if the final step of the project is to win one of the challenges, everyone can say that the majority of the work is done, because the car is built as we wanted.
Good luck for the team for the races, hope the best.
You will have some news from our team during the races.