Pickup Truck Streamlining

[max_frontal_area]

phil, the "grates" that channel airflow to the radiator or a/c cooler
are for the birds. in all the vehicles i worked on, import or domestic there was always a huge gap between them and the radiators, lots of possibility for air to go errand and irrevocably attempting to hit the fins at an angle instead of just flowing through. when u put the gardening tools away think of fashioning
some tighter airflow straigteners and be amazed how lil cooling air your engine acutally needs.
out of pure experimentation i removed the only, thermostatically controlled electric fan on my 82 IDI Jetta wondering if it was possible to go without.
that was 4 years ago. the only time it gets hot is in traffic when i use the heater and simlpy open the windows :=) the aperture is about 2/3 the size of yours, and i left the air snorkle to fend for itself.
b.t.w. i live near the desert in central california.

Bondo:
there is no perceptible gap in the picture of your cab/aerolid, how wide is it actually? the airflow does seem to be seperating but at least it is not going turbulent. the dip generated by the fitup of the aerolid to the cab, and the channel on the top of the aerolid is causing a very interesting swell which is forced to flow over the prevailing airflow going over the top.
very interesting. wonder what would have happened if and exact fitup (more difficult to suit all truck shapes) had been done?

regardless great work!

[bondo]

Hello Max,

The gap is about three quarters of an inch. I think the smoke is behaving like it is in the picture in my earlier post because the attached air on top is meeting the attached air along the side of the Aerolid at the intersection of the two planes. Since the lid slopes back, the attached air runs out of surface to attach to on the sides and mixes with the air flowing over the roof.

The earlier Aerolid I built, the silver one, had a front surface which angles in and meets the angled surface of the rear of the cab. In the later version I built, the white one, I extended the forward surface of the Aerolid to cover the angled rear surface of the cab.

Both versions deliver about a 15% increase in fuel efficiency at freeway speeds. I do like the later version better as far as style goes.

Bondo

[aerohead]

Originally Posted by max_frontal_area

phil, the "grates" that channel airflow to the radiator or a/c cooler
are for the birds. in all the vehicles i worked on, import or domestic there was always a huge gap between them and the radiators, lots of possibility for air to go errand and irrevocably attempting to hit the fins at an angle instead of just flowing through. when u put the gardening tools away think of fashioning
some tighter airflow straigteners and be amazed how lil cooling air your engine acutally needs.
out of pure experimentation i removed the only, thermostatically controlled electric fan on my 82 IDI Jetta wondering if it was possible to go without.
that was 4 years ago. the only time it gets hot is in traffic when i use the heater and simlpy open the windows :=) the aperture is about 2/3 the size of yours, and i left the air snorkle to fend for itself.
b.t.w. i live near the desert in central california.

Bondo:
there is no perceptible gap in the picture of your cab/aerolid, how wide is it actually? the airflow does seem to be seperating but at least it is not going turbulent. the dip generated by the fitup of the aerolid to the cab, and the channel on the top of the aerolid is causing a very interesting swell which is forced to flow over the prevailing airflow going over the top.
very interesting. wonder what would have happened if and exact fitup (more difficult to suit all truck shapes) had been done?

regardless great work!

Max,the inlet opening was sized according to Walter Korff's recommendations for low-drag cooling system design and the inlet duct is airtight,so I'm reluctant to go any smaller for fear of zorching something.
On some mountain ascents I could hear the clutch-fan lockup and start pumping air at the low air speeds.I think I'm near the ragged edge.