Quote:
Originally Posted by California98Civic
I gotta add one edit: up to 100 kph, lift is pretty modest and the car ran at about 90 kph. And I definitely have not seen anyone argue that a streamlined body under yaw would produce no lift. It is an interesting study but it proves less than you seem to think.
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One of the qualifying runs was apparently a top-speed competition, for which the engineers lowered the nose in an attempt to "suppress C
LF increase, in order to achieve the highest possible speed."
Regarding lift and stability, the engineers wrote:
Quote:
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A solar car on the road has to run through natural wind and thus receives its disturbances. The '96 "Dream" was thought to be prone to crosswind disturbances because it was considered lightweight, at approximately 300 kg, with a relatively large body. Fig. 7 shows the crosswind sensibility of the '96 "Dream" measured in wind tunnel tests. It can be seen from the figure that increasing the yaw angle from 0º to 12º (corresponding to receiving side wind of 6 m/s from the lateral direction, while running at 100 km/h) reduces front and rear wheel load by approximately 2.1 and 21.4 kg, respectively. The reduction cannot be neglected because it translates into a 1.4% and 14.2% reduction in front and rear wheel load, respectively. Disturbances induced on vehicle behaviour by lift force resulting from crosswind, as well as other disturbances by side force and yaw moment, must be suppressed to a level low enough not to disturb vehicle driving.
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