4th Quarter 2011, Hydraulic systems & components
The record attempt will take place in 2012 and Hakskeen Pan in the Northern Cape has been chosen as the venue because it has the ideal qualities.
Bloodhound is the brainchild of Richard Noble, who achieved fame in 1997 with the Thrust Supersonic Car (SSC), when Wing Commander Andy Green broke the world landspeed record for a wheeled vehicle by clocking 1220 kph at Mach 1.0.
Powered by a Eurojet EJ200 jet engine and a huge Falcon hybrid rocket, the Bloodhound SSC will develop over 130 000 horsepower, roughly the same power as 180 F1 cars, and will cover 16 km in 100 seconds from a standing start, with a 0 to 1600 kph time of just 42 seconds. At top speed that is four and a half football pitches in one second.
Parker Hannifin is working with the Bloodhound team to develop precision hydraulic systems for the control of the car’s air braking and aerodynamic trim systems. The company will also supply equipment for the development and test phases of the project and for ground support during the timed runs.
Hydraulic systems will play a crucial role in controlling the air brakes and aerodynamic trim. The air brakes will operate in conjunction with drag parachutes and will slow the vehicle, which weighs over 5 tons, from 1600 kph at Mach 1.4 to standstill, over a maximum distance of 7,2 km. Aircraft style disc brakes will be used below 400 kph.
The challenge for designers is far from straightforward as airbrake and parachute systems rely on aerodynamic drag, which changes with speed. Aerodynamic drag is proportional to the square of the speed, so when the speed is doubled the drag is quadrupled. The drag from the airbrake deployed at 1600 kph is four times higher than that at 800 kph, in turn four times higher than the drag at 400 kph. So an airbrake that works well at 1200 kph is ineffective at lower speeds. To control the rate of deceleration, a parachute will be deployed at around 960 kph. This will add a drag load of up to 6 tons to the car, increasing the rate of deceleration by a further 1 g, or an extra 320 kph every second.
It is also crucial to maintain stability during acceleration and deceleration. Again, this is far from straightforward. The aerodynamics and pitch moment change with speed and these forces control the loads on each wheel, influencing their ability to generate lateral forces as each wheel comes into contact with the ground. Each wheel rotates at around 10 000 rpm, generating 50 000 g at the rim, with the aerodynamic forces being controlled by the use of programmable, hydraulically controlled winglets.
The technical challenges for the Bloodhound SSC are immense, both for the vehicle as a whole and for the individual motion and control systems. Yet the main aim of the project is education – to inspire the next generation of engineers with the sheer excitement of science and engineering by sharing the highs and lows of building and running the world’s fastest car.
For Richard Noble and the Bloodhound team the ability to partner with companies such as Parker Hannifin, and to share design, engineering and product skills and knowledge with acknowledged industry experts is an essential factor in this exciting record breaking attempt.
For more information contact Jolanda Bouwer, Parker Hannifin, +27 (0)11 961 0700, firstname.lastname@example.org, www.parker.com/za