SUMMARY OF RESULTS OBTAINED BY TRANSONIC-BUMP METHOD ON EFFECTS. OF PLAN FORM AND THICKNESS ON LIFT AND DRAG CHARACTERISTICS OF WINGS AT TRANSONIC SPEEDS

摘要

This paper presents a summary of the effects of plan form and thickness on the lift and drag characteristics of wings at transonic speeds. The data considered in this summary were obtained during a transonic research program conducted in the Langley high-speed 7- by 10-foot tunnel by the transonic-bump method in the Mach number range from 0.6 to 1.15. The Reynolds numbers of the tests were generally less than 1 x 106. The results indicated that, for subsonic Mach numbers below the force break, theoretical lift-curve-slope calculations were in fair agreement with the experimental results, whereas in the supersonic range the theoretical values were considerably higher than the experimental values. Increasing the thickness ratio caused rather large losses of lift in the transonic speed range and increasing the sweep angle decreased these losses. Decreasing the thickness ratio and increasing the sweep angle increased the drag-rise Mach number and reduced the pressure drag. The sonic pressure drag varied linearly with the 5/3 power of the thickness ratio in accordance with the two-dimensional transonic slailarlty rule. The effect of sweep angle on the maximum pressure drag could also be estimated with good accuracy. In general, the drag due to lift was increased by decreases in thickness ratio, increases in sweep angle, and decreases in aspect ratio.