Abstract The present invention relates to a vehicle, particularly a station wagon, having vortex generators for producing an attached flow over the rear window and/or tailgate in order to overcome the problem of the vehicle''s own tires throwing up slush which quickly covers the rear section of the vehicle, and the front part of vehicles following behind, with a layer of dirt. The vortex generators are designed to reduce the boundary layer of the air flow along the vehicle''s rearward roof surface, gently curved shoulder surface and an obliquely slanted first surface so that separation is prevented over these surfaces and so that an attached flow can be maintained over same. In this way, the turbulent recirculation flow (base flow) will occur only outside of and downstream of a vertical second boundary surface. The vortex generators are a row of substantially rectangular sheets substantially perpendicular to the vehicle roof surface and disposed in pairs that are rearwardly alternately inclined with each sheet forming an angle of no more than 30* with the longitudinal direction of the vehicle.
A vehicle whose rear section has two transverse, substantially plane or gently curved outer boundary surfaces, the first of which is located above the second and comprises a transition surface between the roof of the vehicle and the second surface there being a gently curved shoulder surface as a transition surfacE between the vehicle roof and the first boundary surface which slants obliquely down from said vehicle roof and a window therein, the second boundary surface being substantially vertical, and a plurality of vortex generators on and across the vehicle roof surface, said vortex generators comprising a row of substantially rectangular sheets substantially perpendicular to the vehicle roof surface, said sheets in pairs being rearwardly inclined facing each other, each sheet forming an acute angle not greater than 30* with the longitudinal direction of the vehicle, whereby said vortex generators reduce the boundary layer of the air flow along the rearward roof surface, shoulder surface, and obliquely slanted first surface so that separation is prevented over these surfaces and an attached flow can be maintained over the same whereby turbulent recirculation flow will occur only outside and downstream of the vertical second boundary surface.
Claim 2
Dependent Claim
194 words
A vehicle whose rear section has two transverse, substantially plane or gently curved outer boundary surfaces, the first of which is located above the second and comprises a transition surface between the roof of the vehicle and the second surface there being a gently curved shoulder surface as a transition surfacE between the vehicle roof and the first boundary surface which slants obliquely down from said vehicle roof and a window therein, the second boundary surface being substantially vertical, and a plurality of vortex generators on and across the vehicle roof surface, said vortex generators comprising a row of substantially rectangular sheets substantially perpendicular to the vehicle roof surface, said sheets in pairs being rearwardly inclined facing each other, each sheet forming an acute angle not greater than 30* with the longitudinal direction of the vehicle, whereby said vortex generators reduce the boundary layer of the air flow along the rearward roof surface, shoulder surface, and obliquely slanted first surface so that separation is prevented over these surfaces and an attached flow can be maintained over the same whereby turbulent recirculation flow will occur only outside and downstream of the vertical second boundary surface.
Claim 3
Dependent Claim
41 words
A vehicle according to claim 1, in which the two boundary surfaces comprise the outer surface of a rear door of the vehicle, said vortex generators having an L-shaped cross section and being secured to the roof surface by fastening means.
Claim 4
Dependent Claim
38 words
A vehicle according to claim 1, in which said vortex generators have an L-shaped cross section and are secured by a flexible metal band which is fastened over the vehicle roof by means of fasteners at both ends.