Rishu
20th July 2010, 11:29
The two key talking points in terms of aerodynamic developments in F1 this season has undoubtedly been McLaren’s indigenous F-duct system and Red Bull’s modification of the previously used Blown Diffuser system.
The biggest challenge for an aerodynamicist in Formula 1 is to design a car with maximum downforce. In their quest to achieve this, engineers are constantly challenging the laws of physics and pushing the boundaries.
Brawn GP, Toyota and Williams were in the news prior to the start of the 2009 season owing to their respective controversial rear diffuser designs termed as “Double Diffusers”. Last year the design of the rear diffusers was modified to position them towards the rear to reduce downforce and give the drivers more opportunity to overtake. As a result the teams were forced to find new solutions to counter the lost downforce.
The three teams in question expertly interpreted the rules to find the loopholes to create inlets at the base that feeds the larger outlets and in the process escaped unscathed.
This year the teams made further use of the loopholes to create much larger inlets and outlets. Adrian Newey re-introduced an idea used previously in the sport. The aerodynamic genius decided to mount the exhaust outlets at the lower end of the car towards the floor rather than at the top. As a result, the hot gases escaping the exhaust blow through the diffuser with an increased airflow, giving the car more downforce.
Red Bull seems to have perfected this concept and as a result they have emerged as the team to beat this season so far. With the success of such a system other teams like Ferrari, Renault, Mercedes and now McLaren also have their own versions of such a device.
What is a blown diffuser?
A blown diffuser is a device that is energised by blowing the hot air escaping the exhaust through the diffuser.
How does it create more downforce?
Normally, a standard diffuser creates a low pressure under the car thereby helping it stick to the surface. In case of a blown diffuser, the energy in the exhaust which is a stream of gases moving at high speeds is blown over a curved surface, hence creating much lower pressure under the floor of the car, giving it much more downforce. The pressure under the floor of the car is inversely proportional to the downforce.
Design challenges?
The biggest challenge for a designer when it comes to the blown diffusers is probably to find materials that can withstand being directly exposed to gases at temperatures of around 1000 degrees Celsius. In addition to this, it is very critical to ensure that the hot gases are blown at the right area in order to achieve the maximum suction rate.
How does it affect the driving style?
While driving the amount of air blowing through the diffuser varies as the driver modulates the engine by opening and closing the throttle. This alters the amount of additional downforce being generated. The change is at its maximum while a driver hits the apex and just starts to get back on power. Hence, the drivers constantly need to make delicate adjustments to their driving style to get the maximum output.
Red Bull on the other hand seems to have a mapping system which could be the reason why they have performed so well in the qualifying sessions this year. The system maintains a constant flow of the exhaust gases through the diffusers giving the drivers the additional downforce throughout the lap. However, this cannot be done over the race distance as it may lead to overheating of the rear suspension and it seems that the Milton-Keynes based team has been using this system expertly during qualifying over 1 or 2 laps.
The biggest challenge for an aerodynamicist in Formula 1 is to design a car with maximum downforce. In their quest to achieve this, engineers are constantly challenging the laws of physics and pushing the boundaries.
Brawn GP, Toyota and Williams were in the news prior to the start of the 2009 season owing to their respective controversial rear diffuser designs termed as “Double Diffusers”. Last year the design of the rear diffusers was modified to position them towards the rear to reduce downforce and give the drivers more opportunity to overtake. As a result the teams were forced to find new solutions to counter the lost downforce.
The three teams in question expertly interpreted the rules to find the loopholes to create inlets at the base that feeds the larger outlets and in the process escaped unscathed.
This year the teams made further use of the loopholes to create much larger inlets and outlets. Adrian Newey re-introduced an idea used previously in the sport. The aerodynamic genius decided to mount the exhaust outlets at the lower end of the car towards the floor rather than at the top. As a result, the hot gases escaping the exhaust blow through the diffuser with an increased airflow, giving the car more downforce.
Red Bull seems to have perfected this concept and as a result they have emerged as the team to beat this season so far. With the success of such a system other teams like Ferrari, Renault, Mercedes and now McLaren also have their own versions of such a device.
What is a blown diffuser?
A blown diffuser is a device that is energised by blowing the hot air escaping the exhaust through the diffuser.
How does it create more downforce?
Normally, a standard diffuser creates a low pressure under the car thereby helping it stick to the surface. In case of a blown diffuser, the energy in the exhaust which is a stream of gases moving at high speeds is blown over a curved surface, hence creating much lower pressure under the floor of the car, giving it much more downforce. The pressure under the floor of the car is inversely proportional to the downforce.
Design challenges?
The biggest challenge for a designer when it comes to the blown diffusers is probably to find materials that can withstand being directly exposed to gases at temperatures of around 1000 degrees Celsius. In addition to this, it is very critical to ensure that the hot gases are blown at the right area in order to achieve the maximum suction rate.
How does it affect the driving style?
While driving the amount of air blowing through the diffuser varies as the driver modulates the engine by opening and closing the throttle. This alters the amount of additional downforce being generated. The change is at its maximum while a driver hits the apex and just starts to get back on power. Hence, the drivers constantly need to make delicate adjustments to their driving style to get the maximum output.
Red Bull on the other hand seems to have a mapping system which could be the reason why they have performed so well in the qualifying sessions this year. The system maintains a constant flow of the exhaust gases through the diffusers giving the drivers the additional downforce throughout the lap. However, this cannot be done over the race distance as it may lead to overheating of the rear suspension and it seems that the Milton-Keynes based team has been using this system expertly during qualifying over 1 or 2 laps.