RE: Zenvo TSR-S: Driven
Discussion
Tosh.
The aero argument regarding the way the wing loads up the inner wheel win is pure rubbish. whatever forces generate over the wing's width they are transmitted to the chassis of the car via its connections and supports. it has one central support and the two actuators that do the tilting. assuming that the downforce created by the wing is distributed evenly and transferred evenly then 2/3rds (i.e. via the central structural support and the outside actuator ) will be delivered to the outside wheel. the only way the explanation can work is if the wing flexes so that underload the raised (inside part) exerts more downforce through the inside actuator. But as we know carbon fibre is very rigid. If he has put strain gauges on the actuators and measured the downforce and proven that the inner actuator has more force on it than the outer, i'll apologise and withdraw, but i bet he hasn't.
Bottom line is the downforce, even though it may well be greater on one side of the wing than the other, by virtue of its inherent stiffness, will be being transmitted to the chassis and thus the rear wheels equally across all thee mounting structure.
Paul C
The aero argument regarding the way the wing loads up the inner wheel win is pure rubbish. whatever forces generate over the wing's width they are transmitted to the chassis of the car via its connections and supports. it has one central support and the two actuators that do the tilting. assuming that the downforce created by the wing is distributed evenly and transferred evenly then 2/3rds (i.e. via the central structural support and the outside actuator ) will be delivered to the outside wheel. the only way the explanation can work is if the wing flexes so that underload the raised (inside part) exerts more downforce through the inside actuator. But as we know carbon fibre is very rigid. If he has put strain gauges on the actuators and measured the downforce and proven that the inner actuator has more force on it than the outer, i'll apologise and withdraw, but i bet he hasn't.
Bottom line is the downforce, even though it may well be greater on one side of the wing than the other, by virtue of its inherent stiffness, will be being transmitted to the chassis and thus the rear wheels equally across all thee mounting structure.
Paul C
Max_Torque said:
The question not often asked is
"does the extra mass of all the gubins to mount and actuate the wing outweigh any advantage provided by the aero load redistribution"?
On the Mclaren P1 / Senna, the active wing was a huge job to try to get the system down to a mass where it actually provided a net gain.......
That - minus the actual technological knowledge - is what I've been thinking for years. "does the extra mass of all the gubins to mount and actuate the wing outweigh any advantage provided by the aero load redistribution"?
On the Mclaren P1 / Senna, the active wing was a huge job to try to get the system down to a mass where it actually provided a net gain.......
Race cars have fixed wings, I notice, although that might be down to 'rules'. Maybe more complex race cars have this stuff, but look at what they do when they turn a road car into a GT3 (or whatever it's called these days) car - stick a massive wing on the back.
k, puts me in mind of vectored thrust nozzles and stuff on fighter planes.paulcundy said:
Tosh.
The aero argument regarding the way the wing loads up the inner wheel win is pure rubbish. whatever forces generate over the wing's width they are transmitted to the chassis of the car via its connections and supports. it has one central support and the two actuators that do the tilting. assuming that the downforce created by the wing is distributed evenly and transferred evenly then 2/3rds (i.e. via the central structural support and the outside actuator ) will be delivered to the outside wheel. the only way the explanation can work is if the wing flexes so that underload the raised (inside part) exerts more downforce through the inside actuator. But as we know carbon fibre is very rigid. If he has put strain gauges on the actuators and measured the downforce and proven that the inner actuator has more force on it than the outer, i'll apologise and withdraw, but i bet he hasn't.
Bottom line is the downforce, even though it may well be greater on one side of the wing than the other, by virtue of its inherent stiffness, will be being transmitted to the chassis and thus the rear wheels equally across all thee mounting structure.
Paul C
The whole thing can be perfectly rigid and it will still load up the inner wheel more than the outer one. If you think about the moment created around the inner wheel, as if you are pushing sideways on a sail attached to the top of the car, then the resultant force will tend to lift the outer wheel to counteract it and hence result in the inner wheel taking more of the weight. I'm not sure whether this is a good idea or not; it might get more benefit because the force has a horizontal component pushing the car towards the inside of the corner.The aero argument regarding the way the wing loads up the inner wheel win is pure rubbish. whatever forces generate over the wing's width they are transmitted to the chassis of the car via its connections and supports. it has one central support and the two actuators that do the tilting. assuming that the downforce created by the wing is distributed evenly and transferred evenly then 2/3rds (i.e. via the central structural support and the outside actuator ) will be delivered to the outside wheel. the only way the explanation can work is if the wing flexes so that underload the raised (inside part) exerts more downforce through the inside actuator. But as we know carbon fibre is very rigid. If he has put strain gauges on the actuators and measured the downforce and proven that the inner actuator has more force on it than the outer, i'll apologise and withdraw, but i bet he hasn't.
Bottom line is the downforce, even though it may well be greater on one side of the wing than the other, by virtue of its inherent stiffness, will be being transmitted to the chassis and thus the rear wheels equally across all thee mounting structure.
Paul C
paulcundy said:
Tosh.
The aero argument regarding the way the wing loads up the inner wheel win is pure rubbish. whatever forces generate over the wing's width they are transmitted to the chassis of the car via its connections and supports. it has one central support and the two actuators that do the tilting. assuming that the downforce created by the wing is distributed evenly and transferred evenly then 2/3rds (i.e. via the central structural support and the outside actuator ) will be delivered to the outside wheel. the only way the explanation can work is if the wing flexes so that underload the raised (inside part) exerts more downforce through the inside actuator. But as we know carbon fibre is very rigid. If he has put strain gauges on the actuators and measured the downforce and proven that the inner actuator has more force on it than the outer, i'll apologise and withdraw, but i bet he hasn't.
Bottom line is the downforce, even though it may well be greater on one side of the wing than the other, by virtue of its inherent stiffness, will be being transmitted to the chassis and thus the rear wheels equally across all thee mounting structure.
Paul C
It could be that the raised edge of the wing is getting cleaner air than the edge closer to the car and therefore producing more downforce generating the uneven load on the actuators.The aero argument regarding the way the wing loads up the inner wheel win is pure rubbish. whatever forces generate over the wing's width they are transmitted to the chassis of the car via its connections and supports. it has one central support and the two actuators that do the tilting. assuming that the downforce created by the wing is distributed evenly and transferred evenly then 2/3rds (i.e. via the central structural support and the outside actuator ) will be delivered to the outside wheel. the only way the explanation can work is if the wing flexes so that underload the raised (inside part) exerts more downforce through the inside actuator. But as we know carbon fibre is very rigid. If he has put strain gauges on the actuators and measured the downforce and proven that the inner actuator has more force on it than the outer, i'll apologise and withdraw, but i bet he hasn't.
Bottom line is the downforce, even though it may well be greater on one side of the wing than the other, by virtue of its inherent stiffness, will be being transmitted to the chassis and thus the rear wheels equally across all thee mounting structure.
Paul C
Lamborghini's solution seems more elegant though.
SloWill said:
The whole thing can be perfectly rigid and it will still load up the inner wheel more than the outer one. If you think about the moment created around the inner wheel, as if you are pushing sideways on a sail attached to the top of the car, then the resultant force will tend to lift the outer wheel to counteract it and hence result in the inner wheel taking more of the weight. I'm not sure whether this is a good idea or not; it might get more benefit because the force has a horizontal component pushing the car towards the inside of the corner.
Exactly, think of an aircraft, if it banks it begins to turn in that direction because the wing has both a vertical component to the force and a horizontal component creating a net diagonal force. This is an upside down aircraft so you have to bank the opposite way to achieve the same horizontal force direction.It's transmit the force in the main diagonally through the triangular rear support to the inner wheel, you could theoretically set it up to make zero net difference to the force on the outer wheel if your angles were all correct.
The point about pushing the car into the corner is really interesting actually. Forget about this particular wing for a moment but imagine an active "rudder" which simply generated a horizontal force into the corner. That would achieve greater cornering ability without tyre wear.
je777 said:
Race cars have fixed wings, I notice, although that might be down to 'rules'. Maybe more complex race cars have this stuff, but look at what they do when they turn a road car into a GT3 (or whatever it's called these days) car - stick a massive wing on the back.
Movable aerodynamic components are, to a greater or lesser degree, banned by almost all top-end motorsport formulae. borat52 said:
The point about pushing the car into the corner is really interesting actually. Forget about this particular wing for a moment but imagine an active "rudder" which simply generated a horizontal force into the corner. That would achieve greater cornering ability without tyre wear.
Slightly easier scenario to work with, due to only turning left, but in the USA stock cars are slightly convex on their left side, and slightly concave on their right, so that at ~200mph they have a side force from their aerodynamics to help the left-turning.paulcundy said:
Tosh.
The aero argument regarding the way the wing loads up the inner wheel win is pure rubbish. whatever forces generate over the wing's width they are transmitted to the chassis of the car via its connections and supports. it has one central support and the two actuators that do the tilting. assuming that the downforce created by the wing is distributed evenly and transferred evenly then 2/3rds (i.e. via the central structural support and the outside actuator ) will be delivered to the outside wheel. the only way the explanation can work is if the wing flexes so that underload the raised (inside part) exerts more downforce through the inside actuator. But as we know carbon fibre is very rigid. If he has put strain gauges on the actuators and measured the downforce and proven that the inner actuator has more force on it than the outer, i'll apologise and withdraw, but i bet he hasn't.
Bottom line is the downforce, even though it may well be greater on one side of the wing than the other, by virtue of its inherent stiffness, will be being transmitted to the chassis and thus the rear wheels equally across all thee mounting structure.
Paul C
If we assume that the aerofoil structure does indeed have enough bending stiffness to support the full loading with one end "unsupported" then as long as the hydraulic pressure in the outside end is in fact zero (or close to it) then the lateral forces are translated into a vertical couple by the central support (that has zero torsional stiffness but high vertical / lateral stiffness (due to being a ball joint) and the hydraulic actuator on the inside carrying the entire moment created by the tilted wing. Those vertical members then do apply a non symmetric load to the tyres. No need to use strain gauges to measure that load, just record the hydraulic pressure, which is the same thing......The aero argument regarding the way the wing loads up the inner wheel win is pure rubbish. whatever forces generate over the wing's width they are transmitted to the chassis of the car via its connections and supports. it has one central support and the two actuators that do the tilting. assuming that the downforce created by the wing is distributed evenly and transferred evenly then 2/3rds (i.e. via the central structural support and the outside actuator ) will be delivered to the outside wheel. the only way the explanation can work is if the wing flexes so that underload the raised (inside part) exerts more downforce through the inside actuator. But as we know carbon fibre is very rigid. If he has put strain gauges on the actuators and measured the downforce and proven that the inner actuator has more force on it than the outer, i'll apologise and withdraw, but i bet he hasn't.
Bottom line is the downforce, even though it may well be greater on one side of the wing than the other, by virtue of its inherent stiffness, will be being transmitted to the chassis and thus the rear wheels equally across all thee mounting structure.
Paul C
(as i said above though, i suspect that in all cases, the mass (and high CofG) of the system means it does not actually present a net gain at any speed below about 120 mph.......)
Max_Torque said:
(as i said above though, i suspect that in all cases, the mass (and high CofG) of the system means it does not actually present a net gain at any speed below about 120 mph.......)
Agreed. That thing will be doing next to nothing unless your pinging through a fast sweeper. At corners like La Source mentioned in the article you're just not going fast enough.Gassing Station | General Gassing | Top of Page | What's New | My Stuff