Study of the base drag of tractor-trailer trucks

Conference · Thu Nov 30 23:00:00 EST 1978 · J. Fluids Eng.; (United States)

OSTI ID:6140328

Marks, C H; Buckley, Jr, F T; Walston, Jr, W H

Measurements were made of the base pressure distribution and the aerodynamic drag of a variety of 1/8th-scale tractor-trailer truck models in a wind tunnel at yaw angles ranging from 0/sup 0/ to 20/sup 0/. Base-drag coefficients and overall aerodynamic-drag coefficients were calculated from this data. The measurements show that the base-drag coefficient of typical tractor-trailer trucks does not vary much with vehicle configuration, and that base drag constitutes approximately 13 to 15% of the total aerodynamic drag at zero yaw. The base drag increases in magnitude and also becomes a larger part of the overall aerodynamic drag as yaw angle increases, reaching about 18 to 25% of the overall drag at 20/sup 0/ yaw. Streamlining the forebody of the vehicle has little effect on the base-drag coefficient, but increases the fraction of the overall aerodynamic drag due to the base.

• Research Organization: Univ. of Maryland, College Park
• OSTI ID: 6140328
• Journal Information: J. Fluids Eng.; (United States), Journal Name: J. Fluids Eng.; (United States) Vol. 100:4; ISSN JFEGA
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
320203* -- Energy Conservation
Consumption
& Utilization-- Transportation-- Land & Roadway
AERODYNAMICS
CONFIGURATION
DRAG
ENERGY CONSERVATION
ENERGY CONSUMPTION
FLUID MECHANICS
FUEL CONSUMPTION
MECHANICS
MOCKUP
PERFORMANCE TESTING
STRUCTURAL MODELS
TESTING
TRUCKS
TUNNELS
VEHICLES
WIND TUNNELS