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Old 07-31-2014, 07:18 PM   #37 (permalink)
aerohead
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open/closed

Quote:
Originally Posted by JohnAh View Post
Does a kammback need to have a closed rear end or can it be left open if there's no other way that airflow can enter? If left open, I guess there can be some air oscillation making the whole thing rattle. A rear wall will offcourse make the whole thing more stable. But if making something lika a half kamm-cover over the upper part just to get a slight improvement it sure could make the construction a bit easier. -Don't need extra rear lights and licence plate for example.
If open,you'd have a sort of sculpted box-cavity.
If closed,the recirculating air of separation can strike the rear surface and impart a small degree of forward thrust,something which cannot occur in an open cavity.
One of our members in Belgium tested a tonneau cover with gate down and gate up on hie pickup truck and noticed a slight reduction in performance when the gate was down or off.
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