This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Fuel Savings by Means of Flaps Attached to the Base of a Trailer: Field Test Results
Technical Paper
2005-01-1016
ISSN: 0148-7191, e-ISSN: 2688-3627
Annotation ability available
Sector:
Language:
English
Abstract
This paper presents field test results for fuel savings by means of flat flaps attached to the base of a standard semi trailer. The flaps are constructed from a fiberglass-epoxy-resin material and have a length equal to one-quarter of the trailer-base width (about 61 cm or 2 feet). They are attached along the rear door hinge lines on either side of the trailer and along the trailer roof-line so that no gap appears at the joint between the flap and the trailer base. The flap angle is variable and can be set to 10, 13, 16, 19 or 22 degrees.
Tests were conducted in May 2004 at the NASA Crows Landing Flight Facility in the northern San Joaquin Valley, California.
Analysis of the data show fuel consumption savings at all flap angle settings tested, when compared to the “no flaps” condition. The most beneficial flap angle appears to be 13 degrees, for which the fuel consumption is 0.3778 ±0.0025 liters/km compared to the “no flaps” control of 0.3941 ± 0.0034 liters/km. The error bounds expressed above mark the 99% confidence interval in the mean values given. That is, additional estimates of the mean fuel consumption would be expected to lie within the bounds given, approximately 99% of the time. The fuel consumption saving is-to reasonable accuracy-about 1.63 liters/100 kilometers. These savings represent the increment associated only with the change in drag due to the presence or absence of flaps. The result will hold for any truck of similar size and shape and engine performance regardless of the loading of the truck or the rolling resistance.
Recommended Content
Authors
Topic
Citation
Browand, F., Radovich, C., and Boivin, M., "Fuel Savings by Means of Flaps Attached to the Base of a Trailer: Field Test Results," SAE Technical Paper 2005-01-1016, 2005, https://doi.org/10.4271/2005-01-1016.Also In
SAE 2005 Transactions Journal of Passenger Cars: Mechanical Systems
Number: V114-6; Published: 2006-02-01
Number: V114-6; Published: 2006-02-01
References
- Browand, F. McArthur, J. Radovich, C. “Fuel Saving Achieved in the Field Test of Two Tandem Trucks,” California PATH Research Report June 2004
- Buckley, F. “An Improved Over-the-Road Test Method for Determining the Fuel Saving Benefit of a Truck Aerodynamic Drag Reducing Device,” SAE paper No. 850285 Detroit, Michigan Feb 25 Mar 5 1985
- Cooper, K. “The Effect of Front-Edge Rounding and Rear-Edge Shaping on the Aerodynamic Drag of Bluff Vehicles in Ground Proximity,” SAE paper No. 850288 Detroit, Michigan Feb 25 Mar 1 1985
- Cooper, K. “Truck Aerodynamics Reborn - Lessons from the Past,” SAE paper No. 2003-01-3376 Fort Worth, Texas Nov 10-12 2003
- Hsu, T-Y. Hammache, M. Browand, F. “Base Flaps and Oscillatory Perturbations to Decrease Base Drag,” Proceedings of the UEF Conference on The Aerodynamics of Heavy Vehicles:Trucks, Buses and Trains, Lecture Notes in Applied and Computational Mechanics Springer-Verlag Heidelberg September 2004
- Lanser, W. Ross, J. Kaufman, A. “Aerodynamic Performance of a Drag Reduction Device on a Full-Scale Tractor/Trailer,” SAE paper No. 912125 Long Beach, California Sept 23-26 1991
- Saunders, J. Watkins, S. Hoffmann, P. Buckley, F. Jr. “Comparison of On-Road and Wind-Tunnel Tests for Tractor-Trailer Aerodynamic Devices, and Fuel Savings Predictions,” SAE paper No. 850286 Detroit, Michigan Feb 25 Mar 1 1985
- Storms, B. Satran, D. Heineck, J. Walker, S. “A Study of Reynolds Number Effects and Drag-Reduction Concepts on a Generic Tractor-Trailer,” AIAA paper No. 2004-2251 Portland Oregon Jun 27 Jul 1 2004
- Visser, K. Koon, J. “Drag Reduction of a Tractor-Trailer Using Planar, Non-Ventilated Cavities,” Proceedings of the UEF Conference on The Aerodynamics of Heavy Vehicles:Trucks, Buses and Trains, Lecture Notes in Applied and Computational Mechanics Springer-Verlag Heidelberg September 2004