The EVOLUTION of Aerodynamics
video description
Date: 2020-06-15
Related videos
Comments and reviews: 10
Brendan
A few issues:
1.
The two forces in fluids (thus aerodynamics) are not friction and turbulence, they're shear and pressure. Shear and pressure aren't truly forces in fluids because they need an area to act upon to become a force, as their unit types are [force/area].
2.
The wings on Can Am cars were placed high to get them into clean air AND reduce the lift on the body from the low pressure region created by the wing. The higher the wing, the less lift the body produces. This is why many wings are actally behind the body of cars and why cars with wings over their bodywork typically have the section under them curve up.
3.
Air does not just behave like a fluid, it IS a fluid.
4.
Rain drops are not shaped like a teardrop. The surface tension of the water makes them spherical with a flat bottom. This was really a big error because there are countless videos which show slow-motion footage of rain falling.
reply
A few issues:
1.
The two forces in fluids (thus aerodynamics) are not friction and turbulence, they're shear and pressure. Shear and pressure aren't truly forces in fluids because they need an area to act upon to become a force, as their unit types are [force/area].
2.
The wings on Can Am cars were placed high to get them into clean air AND reduce the lift on the body from the low pressure region created by the wing. The higher the wing, the less lift the body produces. This is why many wings are actally behind the body of cars and why cars with wings over their bodywork typically have the section under them curve up.
3.
Air does not just behave like a fluid, it IS a fluid.
4.
Rain drops are not shaped like a teardrop. The surface tension of the water makes them spherical with a flat bottom. This was really a big error because there are countless videos which show slow-motion footage of rain falling.
reply
Teneuom
The tear drop shape isn t actually what raindrops look like. They look more like hamburger buns.
Also the logic is slightly flawed. Because rain has no eliminating factors to perfect the fastest shape. In other words there are no incentives to make it to the ground faster and nothing stopping slower drops of rain from existing.
If we want to look at nature we should look at fish. All fish are generally the same shape for the same reason, speed.
The faster you are the less likely you ll get eaten, the more food you ll get to first, and the more mates you ll get (because you ll live longer than fish who are slower than you.
The fish shape is a flat-ish, torpedo like a dart. Although they are under water, the same shape should apply to the air as the only difference between those fluids is compressibility.
reply
The tear drop shape isn t actually what raindrops look like. They look more like hamburger buns.
Also the logic is slightly flawed. Because rain has no eliminating factors to perfect the fastest shape. In other words there are no incentives to make it to the ground faster and nothing stopping slower drops of rain from existing.
If we want to look at nature we should look at fish. All fish are generally the same shape for the same reason, speed.
The faster you are the less likely you ll get eaten, the more food you ll get to first, and the more mates you ll get (because you ll live longer than fish who are slower than you.
The fish shape is a flat-ish, torpedo like a dart. Although they are under water, the same shape should apply to the air as the only difference between those fluids is compressibility.
reply
drache444444
well, theres a lot more to car design than the ideal aerodynamic shape; the very common bulky nose is due to crash safety regulations -> a pointier nose would help with drag coefficient. most blocked vents are purely aestetic (whoever likes those) and there have been enough cars with little to no grille at all. most of them didnt sell well enough. actually so bad, that at one point VW face-lifted their early 90 s passat to have a grille again, increasing practical fuel consumption by up to half a liter per 100km.
also drag coefficient =/= drag overall -> fontal area plays a big role in the calculation. so yeah, that minivan has a smaller coefficiant than the m1, but i bet that the m1 has less overall aerodynamic drag, just because it has less than half the frontal area.
reply
well, theres a lot more to car design than the ideal aerodynamic shape; the very common bulky nose is due to crash safety regulations -> a pointier nose would help with drag coefficient. most blocked vents are purely aestetic (whoever likes those) and there have been enough cars with little to no grille at all. most of them didnt sell well enough. actually so bad, that at one point VW face-lifted their early 90 s passat to have a grille again, increasing practical fuel consumption by up to half a liter per 100km.
also drag coefficient =/= drag overall -> fontal area plays a big role in the calculation. so yeah, that minivan has a smaller coefficiant than the m1, but i bet that the m1 has less overall aerodynamic drag, just because it has less than half the frontal area.
reply
Andrew
Don't forget that drag coefficient is only the coefficient of the equation. The rest is frontal surface area in contact with the air, fluid density of the air, multiplied by the drag coefficient, to the square of the speed, divided by two.
So, while a Mercedes A-Class might have a low drag coefficient, a lower, smaller car like the 2002 Honda NSX, might have less actual drag just because it's not actually displacing as much air, despite creating more turbulence. Drag coefficient is only one part of the entire equation!
reply
Don't forget that drag coefficient is only the coefficient of the equation. The rest is frontal surface area in contact with the air, fluid density of the air, multiplied by the drag coefficient, to the square of the speed, divided by two.
So, while a Mercedes A-Class might have a low drag coefficient, a lower, smaller car like the 2002 Honda NSX, might have less actual drag just because it's not actually displacing as much air, despite creating more turbulence. Drag coefficient is only one part of the entire equation!
reply
RubyByte
You inaccurately neglected that drag is caused by coefficient of drag AND cross section area. A corolla and a 100x scaled up corolla have the same coefficient of drag, but the larger one still receives 100x more drag.
The comparison of the BMW M1 to the Toyota Sienna makes no sense because the M1 will still have less drag because it's cross section area is 1/2 of the Sienna's
reply
You inaccurately neglected that drag is caused by coefficient of drag AND cross section area. A corolla and a 100x scaled up corolla have the same coefficient of drag, but the larger one still receives 100x more drag.
The comparison of the BMW M1 to the Toyota Sienna makes no sense because the M1 will still have less drag because it's cross section area is 1/2 of the Sienna's
reply
CalgarGTX
A BMW M1 might have 0. 40 cd and a sienna 0. 30 but I'm pretty sure the M1 has like half the total frontal area. Drag is cd x frontal area, this is way too often forgotten when talking about how new SUVs etc are so efficient because they have a better cd than the last gen. As long as they are huge it doesn't matter.
reply
A BMW M1 might have 0. 40 cd and a sienna 0. 30 but I'm pretty sure the M1 has like half the total frontal area. Drag is cd x frontal area, this is way too often forgotten when talking about how new SUVs etc are so efficient because they have a better cd than the last gen. As long as they are huge it doesn't matter.
reply
Duncan
Drag coefficient isn't all that that defines the drag from a vehicle! The reference area is also very important. Hence why some vehicles (like the M1 and the Caterham 7 at 0. 7) have a suspiciously high drag coefficient! They have a substantially smaller reference area than the Sienna.
Source: Aero engineer
reply
Drag coefficient isn't all that that defines the drag from a vehicle! The reference area is also very important. Hence why some vehicles (like the M1 and the Caterham 7 at 0. 7) have a suspiciously high drag coefficient! They have a substantially smaller reference area than the Sienna.
Source: Aero engineer
reply
BlackLion
Raindrops are actually not shaped like teardrops when they fall from the sky. They form a contact lense shape facing upwards when in free fall. Similar to trying to blow a bubble with bubblegum; air pushes to the center of the raindrop and pushes upwards. It is also why parachutes take that similar shape.
reply
Raindrops are actually not shaped like teardrops when they fall from the sky. They form a contact lense shape facing upwards when in free fall. Similar to trying to blow a bubble with bubblegum; air pushes to the center of the raindrop and pushes upwards. It is also why parachutes take that similar shape.
reply
Brett
Well done as usual but for one striking absence: only US car to win FIA world championship, and it was not a winner internationally until a young Mr Brock fixed its Aerodynamics
Same car chosen as first entrant to Smithsonian for us car design. just saying
Shelby Daytona Coupe
reply
Well done as usual but for one striking absence: only US car to win FIA world championship, and it was not a winner internationally until a young Mr Brock fixed its Aerodynamics
Same car chosen as first entrant to Smithsonian for us car design. just saying
Shelby Daytona Coupe
reply
Parth
Technically the Fan in the Fan car WAS used to cool the engine, 55%of it s use was to cool down the engine and the rest (45%) of it s effect was downforce generation. Plus the car wasn t banned by F1, it was willingly withdrawn due to Bernie Ecclestone
reply
Technically the Fan in the Fan car WAS used to cool the engine, 55%of it s use was to cool down the engine and the rest (45%) of it s effect was downforce generation. Plus the car wasn t banned by F1, it was willingly withdrawn due to Bernie Ecclestone
reply
Add a review, comment
Other channel videos
