A procedure has been developed for predicting the upwash compo-nents of the upflow angles in the region above or below the wing-chord planes of swept-back wing-fuselage-nacelle combinations. This procedure entails modifications to the methods given in NACA TN's 2528 and 2795, for predicting induced upwash angles.nComparisons of predicted and measured upflow angles are shown for six semispan models with 40° swept-back wings. The models differ mainly in nacelle location (spanwise, chordwise, and vertical relative to the wing). For all models, the agreement between the measured and predicted upflow angles was found to be good for all points along the horizontal center line of the propeller disks.nThe accuracy of the upflow angles obtained by this procedure is considered satisfactory for use in estimating propeller vibratory stresses.
展开▼
