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ABCD - An Improved Coast Down Test and Analysis Method
ISSN: 0148-7191, e-ISSN: 2688-3627
Published February 01, 1995 by SAE International in United States
Annotation ability available
An improved coast down method that incorporates the input of data measured with an onboard anemometer into the governing equation of motion is used to evaluate models representing the aerodynamic and mechanical drag characteristics of a wide variety of vehicles. Results from the application of the improved technique are presented to demonstrate the repeatability and precision of the analyzed aerodynamic drag coefficients, to address the merits of different wind tunnel blockage correction methods, to illustrate the method's usefulness in the study of tractor-trailer and light truck-travel trailer aerodynamic drag, to evaluate the influence of floor blowing in wind tunnel studies of the effects of various changes to the underbody of an automobile, and to compare track and dynamometer determinations of the variation of mechanical drag with speed on a vehicle equipped with a four-speed automatic transmission.
|Technical Paper||A Detailed Drag Study Using the Coastdown Method|
|Technical Paper||Coast Down Method in Time-Distance Variables|
|Technical Paper||The Determination of Vehicle Drag Contributions from Coast-Down Tests|
CitationBuckley, F., "ABCD - An Improved Coast Down Test and Analysis Method," SAE Technical Paper 950626, 1995, https://doi.org/10.4271/950626.
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