The Principles of Aerodynamic Drag and Rolling Resistance as they relate to vehicle fuel consumption

Transport
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For the scientific and mathematically inquisitive.
Fuel or energy consumption for transport is a complex discussion. In particular when looking at ways to reduce fuel use (ICE - petrol, diesel, biofuel etc). Also relevant to other types of motive power such as BEV.

The Drag Equation.

Nothing to do with fashion choices.

To infinity and beyond!

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P.S.
Someone might like to explain rolling resistance and the differences between laminar flow and turbulent flow. Budding F1 vehicle aerodynamic designers welcome.

I’ve collected some recent posts to add to the discussion.

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It should be noted that the drag due to air resistance increases exponentially with speed as in F=1/2V^2 so double the speed, four times the drag.

The same thing applies in braking. Double the speed, four times the distance to brake. Which is why road safety authorities bang on all the time about reducing the speed limits.

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Got any fuel saving tips?
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Your idea is correct, people need to understand why fuel consumption increases and braking takes longer as speed increases.

The math is a little off though. A better way to put it is:

KE ∝ V^2

Kinetic energy is proportional to the square of the velocity, which is quadratic not exponential.

So if your brakes can only reduce energy linearly braking distance increases as the square of velocity.

The formula for air drag is more complex but also non-linear, so fuel consumption increases with speed too.

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