Quote:
Originally Posted by Andyinchville1
HI,
Just curious but isn't the trailer tail basically a boxed cavity ?
Also, In some of the trailer tail pics I noticed that the sides and / or the bottom panels don't go down as far as it could (or should ?) does this hurt efficiency?
When I build the trailer tail my idea would be to go down more or less to where my rear bumper is (or would have been if I in fact had a rear bumper (the van did not come with one and I hacve not been able to find one at a junkyard).... I'm guessing that would be best for drag reduction?
|
* The 'Trailer Tail' differs from a box-cavity in that:
- its sides are angled rather than 'stepped.'
- the enclosed volume is exposed to 'leakage.'
- it, as mentioned, does not span the entire vertical distance ( volume ), from roof-to-belly, as in some box-cavities reported.
-------------------------------------------------------------------------------------
* A 'junkyard' Trailer Tail would be 'way out ahead of nothing' ( Robert Parsons ).
* Fabricating something from 'scratch' would likely exceed the performance of the Trailer Tail.
--------------------------------------------------------------------------------------
* The original box-cavity, by Continuum Dynamics, DARPA small business administration grant, tested at NASA Ames, Palo Alto, California.
--------------------------------------------------------------------------------------
* Smoke flow imaging of Golf-I at Volkswagen reveals the wake drag your tail will be fighting.
--------------------------------------------------------------------------------------
* NASA boat tail, 1980
-------------------------------------------------------------------------------------
* NASA boat tail, Space Shuttle, 1977, ( note, 'bottom' of tail is compromised
due to large angle-of-attack tail-dragging prevention requirement of delta wing vortex-lift at landing, not a constraint for 'ecomodders' on the road.