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美国政府科技报告
>INVESTIGATION AT SUPERSONIC SPEEDS OF THE VARIATION WITH REYNOLDS NUMBER AND MACH NUMBER OF THE TOTAL, BASE, AND SKIN-FRICTION DRAG OF SEVEN BOATTAIL BODIES OF REVOLUTION DESIGNED FOR MINIMUM WAVE DRAG
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INVESTIGATION AT SUPERSONIC SPEEDS OF THE VARIATION WITH REYNOLDS NUMBER AND MACH NUMBER OF THE TOTAL, BASE, AND SKIN-FRICTION DRAG OF SEVEN BOATTAIL BODIES OF REVOLUTION DESIGNED FOR MINIMUM WAVE DRAG
An investigation has been conducted in the Langley 9-inch supersonic tunnel to determine the effect of the variation with Reynolds number and much number of the total, base, and skin-friction drag at zero lift of seven boat tail bodies of revolution designed for minimum wave drag according to NACA Technical Note 2550. The investigation covered a Reynolds number range from approximately 1.0 X 10" to 10.0 X 106 at Mach numbers of 1.62, 1.93, and 2.41, respectively. The results show that base drag and, in general, the total drag increase with increasing values of the ratio of base area to maximum area B/S max, although the results reported in NACA Technical Note 3054 shoved that the, wave drag decreased with increasing values of B/S max The laminar skin-friction drag is in agreement with the theoretical predictions used, and, within the Mach number range of these tests, the simple blasius incompressible theory gives a satisfactory prediction. Except for values of B/S max near 1, the Reynolds number of transition Increases with increasing much number and, as this ratio approaches 1, this variation is seen to reverse. These variations in Reynolds number of transition with Mach number appear to be associated with the changes in pressure gradient over the rear of the bodies.
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