Optimizing Aerodynamics of a Truck: Part 1

[freebeard]

I haven't given up on your "Imagine vertical up DBD from the vertical bit...".

The current surmise is that you're suggesting placing DBD slightly above the stagnation point to virtually bluff-terize the squared off nose? To make it more Beetle-like?


https://external-content.duckduckgo....Fpid%3DApi&f=1

Tesla uses a horizontal concavity to send air to the sides, if I am reading this right.

[Logic]

Everyone:
DBD is as easy as some Kapton Tape and some conductive metal tape that can be temporarily stuck wherever, moved around and removed easily!
(And a LOW amp - High Volt power supply.)

Then:

On the classification of dielectric barrier discharge plasma actuators: A comprehensive
performance evaluation study

For a justification for the application of the flow control system, an efficiency (in that case: effectiveness) greater than 1 would be necessary.
The analysis of the efficiency of all components of the efficiency chain reveals an extraordinary good saving rate of around 54, which means in other words:
More than 50 times the fluid mechanic power spent for the boundary-layer control is saved in the propulsion power.

Hence the interest!

Originally Posted by freebeard

I haven't given up on your "Imagine vertical up DBD from the vertical bit...".

The current surmise is that you're suggesting placing DBD slightly above the stagnation point to virtually bluff-terize the squared off nose? To make it more Beetle-like?


https://external-content.duckduckgo....Fpid%3DApi&f=1

Tesla uses a horizontal concavity to send air to the sides, if I am reading this right.

Well where exactly to start and end some DC DBD relative to the front stagnation point would be 'The Experiment'!
At a guess I would say one would want to start within the high pressure stagnation area and 'start pumping a flow' toward the low pressure, high speed, curved back, suction causing, upper part of the nose.
ie:
Change 'stagnant' into flow and even higher speed, more suction, flow! Over that nose curve.

I NB the similarity of the nose to everyone here's fav; ideal and simple Aero Template.
So this is basically a case of improving on 'The Template' and all that inconvenient ground effect of 'molecules pile up' (stagnant) ahead of it by giving them an 'up and over direction'...

[Logic]

https://www.youtube.com/watch?v=pJd0B-8rBxA

IMHO All this talk about air flowing over the tailgate vs getting caught and swirled by it is speed dependent:
Drive faster and it goes over; slower and it doesn't.
As most all people are driving varying speed 'Urban Cycles' just about all the time, the point is moot!?

So (weight excepted) these are the best solution. And this one is practical, durable and looks the part:

https://ecomodder.com/forum/showthre...d-cap-583.html

[freebeard]

Optimal for some use cases. Not retractable like the Cybertruck.



Other sources put the half tonneau in second place..

[Logic]

Originally Posted by freebeard

Optimal for some use cases. Not retractable like the Cybertruck.



Other sources put the half tonneau in second place..

Speed? What speed were the above test conducted at?

We had an old 1600 Nissan IIRC truck:
Top speed with tailgate up: 100km/h
Top speed with tailgate down: 110km/h
A 10km/h increase is a lot, what with drag increasing with the square of speed.
So:
My own experience with that vehicle goes against the above findings. So now??!

Now had the truck been capable of doing say 130km/h; the air may have gone over the tailgate and I would have had a different experience..?

My point being: If you want to skip all that (speed dependent?) uncertainty go with a speed independent light Aero Shell.
And possibly some DBD!

[freebeard]

Speed? What speed were the above test conducted at?

Ya gots me. The picture was capture from some thread in 2013 (Picture Added 05-29-2013 07:25 PM)

We had an old 1600 Nissan IIRC truck:
Top speed with tailgate up: 100km/h
Top speed with tailgate up: 110km/h
A 10km/h increase is a lot, what with drag increasing with the square of speed.

Yeah, but what about with tailgate up?

"If you want to skip all that (speed dependent?) uncertainty go with..." a bubble-top coupe.

[Logic]

Originally Posted by freebeard

Yeah, but what about with tailgate up?

Oops!
Top speed with tailgate up: 100km/h
Top speed with tailgate down: 110km/h
Thx for catching that. Edited.