Abstract: The present invention provides a vortex generator that in one embodiment includes an apex having a first width; a rear face having a second width being greater than the first width; a first and second sidewall each extending from the first width of the apex to the second width of the rear face, wherein at least a portion of each of the first and second sidewall have a peak including a convex surface; and a concave work surface positioned between the peak of the first and the second sidewall, wherein the concave work surface has an intake at the apex and an outlet at the rear face. In another embodiment, the exterior faces of the sidewalls include a planar surface.

Abstract: The present invention provides an air shield comprising side panel assemblies in hinged connection to each rear edge of a sidewall of a tractor and an actuation assembly including a boss in rotational engagement to the frame of the tractor and between a cab and a fifth wheel of the tractor, a lever having an adjustable length engaged to the boss at a first end and engaged to side panel assembly at a second end, and a spring including a first end connected to the side panel assembly and a second end connected to the frame of the tractor between the boss and the rear of the trailer frame.