I am basing my question off this [image](https://study.com/cimages/multimages/16/dragcoefficients8851096396303799158.png)
Edit: Okay, okay, I should have said “teardrop” instead of “raindrop.” Talking about the *actual* shape of raindrops doesn’t really help given the visuals I provided.
In: 558
Along with everyone else’s points, keep in mind that topology plays a part. That raindrop is a single solid object whereas a car can have air got through the grill, engine bay, cabin, etc. The most aerodynamic solution becomes infinitely more complex based off that alone.
On top of that, there’s value in the air resistance. If you want performance, you need to generate downforce to stay on the road and maintain grip. If you don’t counter air resistance enough, at higher speeds, you’re losing grip, potentially lowering power output, potentially even generating some degree of lift which could lead to lack of control. In essence, the physics might say it’s a good idea, but the engineering and economics say it’s a bad idea.
Before the 1990’s cars were boxes with lots of sharp edges. Rounding the corners did a lot for aerodynamics and fuel efficiency, but other factors like safety and practicality are important. Having the motor at the front protects the passengers in a crash. Having a box shape means maximizing the internal volume compared to the “footprint” of the car. Holding more stuff and passengers compared to the size makes the car more efficient in a different way.
Before the 1990’s cars were boxes with lots of sharp edges. Rounding the corners did a lot for aerodynamics and fuel efficiency, but other factors like safety and practicality are important. Having the motor at the front protects the passengers in a crash. Having a box shape means maximizing the internal volume compared to the “footprint” of the car. Holding more stuff and passengers compared to the size makes the car more efficient in a different way.
Not an expert in aerodynamics, so this is just a half answer. There are other considerations in automotive aerodynamics other than drag.
Downforce is more important for performance at the speeds the cars drive at, as this lets the car grip the road better at higher speeds. Cars with strong downforce often have a rear end that is broad, close to the ground, but then slightly tapering upwards at the very end.
Air intake both to cool radiators and feed the engine is also very important and likely also changes design considerations. This could prevent a very low drag shape. A smooth shape allowing for laminar (smooth and regular) air flow might cause air to pass around an intake rather than be funneled into the intake. With a teardrop shape, the very front is perpendicular to airflow as it deflects air *around* the cross section of the bulk of the object. If an intake were placed on such a shape that is flush with the shape, the laminar air flow would travel perpendicular to the intake duct. If the intake were instead elevated off the surface of the object, then the intake would contribute to a new “front cross section” of the shape and nullify the advantage of the front of the teardrop deflecting the incoming air.
Some expensive automobiles that are marketed based on top-speed capability do have a bit more of a teardrop shape, such as the McLaren Speedtail.
Not an expert in aerodynamics, so this is just a half answer. There are other considerations in automotive aerodynamics other than drag.
Downforce is more important for performance at the speeds the cars drive at, as this lets the car grip the road better at higher speeds. Cars with strong downforce often have a rear end that is broad, close to the ground, but then slightly tapering upwards at the very end.
Air intake both to cool radiators and feed the engine is also very important and likely also changes design considerations. This could prevent a very low drag shape. A smooth shape allowing for laminar (smooth and regular) air flow might cause air to pass around an intake rather than be funneled into the intake. With a teardrop shape, the very front is perpendicular to airflow as it deflects air *around* the cross section of the bulk of the object. If an intake were placed on such a shape that is flush with the shape, the laminar air flow would travel perpendicular to the intake duct. If the intake were instead elevated off the surface of the object, then the intake would contribute to a new “front cross section” of the shape and nullify the advantage of the front of the teardrop deflecting the incoming air.
Some expensive automobiles that are marketed based on top-speed capability do have a bit more of a teardrop shape, such as the McLaren Speedtail.
2 dutch friends did something similar.
Unfortunately it is in dutch, but still worth watching.
Source: i live in the Netherlands and i saw this on television.
2 dutch friends did something similar.
Unfortunately it is in dutch, but still worth watching.
Source: i live in the Netherlands and i saw this on television.
2 dutch friends did something similar.
Unfortunately it is in dutch, but still worth watching.
Source: i live in the Netherlands and i saw this on television.
Specific to the teardrop (and the extent of aerodynamics I know) with respect to cars, you’re not looking at just moving through the air with minimum drag — that’s not the optimization problem here, nor is it the optimization for planes and trains. Consumer cars need traction at all angles, and in many/most designs (and sadly for engineers and environmentalists) they need wheels with enough ground clearance to go over potholes and bumps, and worst of all they want protruding side mirrors (instead of more recent camera-only options). This gives rise to [unique aerodynamics optimizations](https://en.wikipedia.org/wiki/Automotive_aerodynamics) — the flat bottom being sealed so that air is redirected strategically to minimize drag in certain parts, maximize pressure in others, etc.. I’d say the abrupt, sharp cutoff to the back is the most counterintuitive part of car design imo, but that is apparently what produces the least drag for the overall shape.
Anywho, this is why I keep my cows spherical.
Specific to the teardrop (and the extent of aerodynamics I know) with respect to cars, you’re not looking at just moving through the air with minimum drag — that’s not the optimization problem here, nor is it the optimization for planes and trains. Consumer cars need traction at all angles, and in many/most designs (and sadly for engineers and environmentalists) they need wheels with enough ground clearance to go over potholes and bumps, and worst of all they want protruding side mirrors (instead of more recent camera-only options). This gives rise to [unique aerodynamics optimizations](https://en.wikipedia.org/wiki/Automotive_aerodynamics) — the flat bottom being sealed so that air is redirected strategically to minimize drag in certain parts, maximize pressure in others, etc.. I’d say the abrupt, sharp cutoff to the back is the most counterintuitive part of car design imo, but that is apparently what produces the least drag for the overall shape.
Anywho, this is why I keep my cows spherical.
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