Lotus to debut Coandă exhausts in Korea
9 October 2012 – As part of a massive update package which is aimed at propelling Kimi Räikkönen back into the championship hunt, Lotus are taking a raft of upgrades to Korea this weekend. The Enstone team is hoping new, Coandă-style exhausts will help to ensure that downforce levels are significantly increased.
As directing exhaust gases straight into the diffuser of a Formula 1 car has been banned since the end of 2011, teams have been busily using this year to come up with alternative strategies. The Coandă effect involves pointing exhaust exits upwards, taking advantage of airflow’s tendency to curve back towards the ground and therefore the diffuser.
“We’ve been ploughing something of a lonely furrow on the circuit with our relatively straightforward, power-maximizing exhaust,” explains Lotus Technical Director James Allison. “However, since well before the launch of the E20 and to the present day we’ve been carrying out parallel developments in our wind tunnel programme based around a Coandă effect exhaust.
“Once we saw the potential gain of the Coandă system surpass that of our current design it was clear that we needed to implement it, both for the benefit we could get in the last quarter of this season and also for learning experience it presents us for next year. We will run our first version of this style of exhaust in Korea.”
The Coandă exhausts are already being used by McLaren, Ferrari and Sauber, with Mercedes having trialled the principle at the Magny-Cours Young Driver test. Allison explains that the concept is not as complicated as the intricate, forward-pointing exhausts used by Lotus (then Renault) last season, which at times created fires.
“It is not as big a deal as the 2011 style blown exhausts,” he continues. “Last year - for all teams, but especially for our forward exhausts - it was quite challenging to ensure that the exhausts did not set fire to the car. The Coandă system is a little more indirect and the jet has cooled a little before it impinges on the floor, which makes things a little easier to manage.
“There’s still a fair amount of rearrangement including new coke panels, new exhausts, new exhaust exit panels, some fireproofing of the floor and so on. All told, it’s a biggish change rather than an enormous one. It’s also easier to swap to and fro for evaluation.”
Allison added that the ‘Double DRS’ concept, which Lotus had hoped to race at Suzuka but again shelved because of calibration problems, will undergo a large development programme in next month’s Abu Dhabi Young Driver Test.