|
The one thing people forget when positing low-drag car bodies is stability. The classic half-teardrop is a stability nightmare as soon as the air flow deviates from straight ahead. Add a vertical fin along the medial line in back and the nightmare's averted.
The issue is torque around a vertical axis, yaw in aeronautics. When the center of pressure is forward of the center of mass, crosswinds turn the car, and the farther it turns, the greater the torque. The vertical fin has little effect when airflow is parallel to it, but acts like a parachute in back in crosswinds, countering the torque on the front of the car, and keeping you pointed in the same direction, albeit perhaps a few feet downwind.
The wing-based design gains stability from the slab sides, while CUER and Bochum U are not suitable for road use, based on the views shown (could gain stability from features not visible in the photos).
Just another aspect to consider...
Frank
|