Aerodynamic trailer apparatus with optimized small skirt
An apparatus ( 10 ) for a trailer ( 12 ) is provided that has a trailer skirt ( 14 ) configured for attachment to the trailer ( 12 ). A majority of the outer surface length of an outer surface ( 16 ) of the trailer skirt ( 14 ) is oriented at a 3-7 degree angle to the longitudinal direction, and the majority of the outer surface length extends inboard in the lateral direction upon extension forward of the trailer skirt ( 14 ) in the longitudinal direction. An overall length/overall height ratio of the trailer skirt ( 14 ) is 6 or less. The trailer length in the longitudinal direction is at least 10.668 meters (35 feet). A majority of the outer surface length is located rearward of a longitudinal midpoint of the trailer. A rib cover ( 74 ) is present and is located higher than a bottom edge of the trailer skirt ( 14 ) in the height direction.
1 . An apparatus for a trailer that has a longitudinal direction, a lateral direction, and a height direction, comprising:
a trailer skirt configured for attachment to the trailer, wherein the trailer skirt has an outer surface that has an outer surface length, wherein a majority of the outer surface length is oriented at an angle from 3 degrees to 7 degrees to the longitudinal direction such that the majority of the outer surface length extends inboard in the lateral direction upon extension forward in the longitudinal direction;
wherein the trailer skirt has an overall length in the longitudinal direction and an overall height in the height direction that has an overall length/overall height ratio that is 6 or less;
wherein the trailer has a trailer length in the longitudinal direction that is at least 35 feet, wherein the trailer has a longitudinal midpoint that is located in the longitudinal direction, and wherein a majority of the outer surface length is located rearward of the longitudinal midpoint in the longitudinal direction;
a rib cover that is carried by the trailer, wherein the rib cover is located higher than a bottom edge of the trailer skirt in the height direction, wherein the rib cover is wedge shaped and located outboard from the trailer skirt in the lateral direction;
wherein the trailer has a plurality of cross-members that extend in the lateral direction and are spaced from one another in the longitudinal direction, wherein the rib cover covers increasingly larger portions of successive cross-members upon extension of the rib cover forward in the longitudinal direction.
2 . The apparatus as set forth in claim 1 , wherein the angle that the majority of the outer surface length is oriented to the longitudinal direction is from 5 degrees to 6 degrees.
3 . The apparatus as set forth in claim 1 , wherein the trailer has a forward terminal end and a rearward terminal end and the trailer length extends in the longitudinal direction from the forward terminal end to the rearward terminal end, wherein a 30% point of the trailer is at a location that is distanced 30% of the trailer length from the forward terminal end in the longitudinal direction;
wherein no portion of the trailer skirt is located forward of the 30% point in the longitudinal direction.
4 . The apparatus as set forth in claim 1 , wherein the trailer length is at least 48 feet.
5 . The apparatus as set forth in claim 4 , wherein the trailer length is 53 feet.
6 . The apparatus as set forth in claim 1 , wherein the rib cover is configured to engage a lower surface of the trailer.
7 . The apparatus as set forth in claim 1 , wherein the entire outer surface of the trailer skirt is flat, and wherein the entire outer surface of the trailer skirt is oriented at the angle from 3 degrees to 7 degrees to the longitudinal direction.
8 . The apparatus as set forth in claim 1 , wherein the overall length/overall height ratio of the trailer skirt is 5 or less.
9 . The apparatus as set forth in claim 1 , wherein the trailer has a bogie assembly that has a plurality of tires, and wherein the entire trailer skirt is configured for being located forward of all of the plurality of tires of the bogie assembly in the longitudinal direction, and wherein the entire rib cover is configured for being located forward of all of the plurality of tires of the bogie assembly in the longitudinal direction.
10 . The apparatus as set forth in claim 9 , wherein the trailer has landing gear, and wherein the entire trailer skirt is configured for being located rearward of the landing gear in the longitudinal direction, and wherein the entire rib cover is configured for being located rearward of the landing gear in the longitudinal direction.
11 . The apparatus as set forth in claim 1 , further comprising an aerodynamic mud flap configured to be carried by the trailer, wherein the aerodynamic mud flap is located rearward of the trailer skirt in the longitudinal direction, wherein the aerodynamic mud flap has a barrier section that includes apertures therethrough that allow air and particles to flow through the barrier section during travel of the trailer.
12 . The apparatus as set forth in claim 1 , further comprising a top fairing configured for being mounted to a top surface of the trailer, wherein the top fairing is configured to be located closer to the rearward terminal end of the trailer than to the forward terminal end of the trailer in the longitudinal direction.
13 . The apparatus as set forth in claim 12 , wherein the top fairing does not extend rearward of the rearward terminal end of the trailer in the longitudinal direction; and
wherein the top fairing, the trailer skirt, and the rib cover do not have any moving parts during use of the trailer.
14 . The apparatus as set forth in claim 1 , wherein the overall length of the trailer skirt is 25% or less of the trailer length.
15 . The apparatus as set forth in claim 1 , wherein there are no further skirts configured for attachment to the trailer forward of the trailer skirt in the longitudinal direction that are on the same side of the trailer as the trailer skirt.
16 . An apparatus for attachment to a trailer having a plurality of cross-members, comprising:
a trailer skirt having an outer surface that faces away from a center of the trailer when the trailer skirt is attached to the trailer; and
a rib cover extending from the outer surface of the trailer skirt, the rib cover is located higher than a bottom edge of the trailer skirt in a height direction and is shaped to cover increasingly larger portions of successive cross-members of the trailer when the trailer skirt is attached to the trailer.
17 . The apparatus as set forth in claim 16 , wherein the rib cover is shaped such that the rib cover is flush with a side of the trailer when the trailer skirt is attached to the trailer at an angle relative to a longitudinal direction of the trailer.
18 . The apparatus as set forth in claim 16 , wherein the rib cover is wedge shaped.