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Message: I believe a "spoiler" is just that:
Changed By: Laz
Change Date: October 14, 2011 05:16PM
I believe a "spoiler" is just that:
Change Date: October 14, 2011 05:16PM
I believe a "spoiler" is just that:
Although its design might create some downforce, its main function is to break up the smooth, but less dense airflow that would otherwise pass over the rearmost part of the tail section. This smooth (I don't know anywhere near enough to safely use the term laminar) flow's lower density exerts less force on the surface of the car. This is ok on the car's sides, and maybe bottom, but on a top surface this can allow the car to be "sucked up." (The underside is actually being pushed up.) There are myriad factors affecting the pressure on the car's exterior as a whole, but the spoiler helps counteract the lift occurring at the rear. Although there is still lift at speed, the net lift is reduced.
A wing, on the other hand, can be configured to create more or less downforce, with attendant more or less weight and tire force on the road surface. To a certain point, the car effectively weighs more at speed than it does when stationary.
I believe (but stand to be corrected) that the negative aspect of any of these anti-lift or downforce increasing devices is to cause more aerodynamic drag, making the vehicle less efficient.
Oh boy, now I'm thinking of aerodynamic center of pressure in relation to center of mass! (One reason why arrows have fletching and some rockets have fins.)
A wing, on the other hand, can be configured to create more or less downforce, with attendant more or less weight and tire force on the road surface. To a certain point, the car effectively weighs more at speed than it does when stationary.
I believe (but stand to be corrected) that the negative aspect of any of these anti-lift or downforce increasing devices is to cause more aerodynamic drag, making the vehicle less efficient.
Oh boy, now I'm thinking of aerodynamic center of pressure in relation to center of mass! (One reason why arrows have fletching and some rockets have fins.)
Original Message
Author: LazDate: October 14, 2011 05:11PM
I believe a "spoiler" is just that:
Although its design might create some downforce, its main function is to break up the smooth, but less dense airflow that would otherwise pass over the rearmost part of the tail section. This smooth (I don't know anywhere near enough to safely use the term laminar) flow's lower density exerts less force on the surface of the car. This is ok on the car's sides, and maybe bottom, but on a top surface this can allow the car to be "sucked up." There are myriad factors affecting the pressure on the car's exterior as a whole, but the spoiler helps counteract the lift occurring at the rear. Although there is still lift at speed, the net lift is reduced.
A wing, on the other hand, can be configured to create more or less downforce, with attendant more or less weight and tire force on the road surface. To a certain point, the car effectively weighs more at speed than it does when stationary.
I believe (but stand to be corrected) that the negative aspect of any of these anti-lift or downforce increasing devices is to cause more aerodynamic drag, making the vehicle less efficient.
Oh boy, now I'm thinking of aerodynamic center of pressure in relation to center of mass! (One reason why arrows have fletching and some rockets have fins.)
A wing, on the other hand, can be configured to create more or less downforce, with attendant more or less weight and tire force on the road surface. To a certain point, the car effectively weighs more at speed than it does when stationary.
I believe (but stand to be corrected) that the negative aspect of any of these anti-lift or downforce increasing devices is to cause more aerodynamic drag, making the vehicle less efficient.
Oh boy, now I'm thinking of aerodynamic center of pressure in relation to center of mass! (One reason why arrows have fletching and some rockets have fins.)