The results showed that, for slot configurations which produced high lift, the lift increased rapidly at low momentums and less rapidly at higher momentums in a manner similar to that obtained with jet-flap wings having high lift-producing capabilities. The variation of lift coefficient with momentum coefficient could be correlated with that obtained on a jet-flap wing of a previous investigation on the basis of equal drag. The lift coefficients (also the drag coefficient) were strongly influenced by slot position for slot configurations covering less than half the cylinder circumference. For example, with three slots 45° apart and a momentum coefficient of 6, the lift coefficients could be varied from -6 to about 2k by varying the reference slot position. At these high momentum coefficients, very abrupt stalls occurred for slot positions greater than that for maximum lift. For slot configurations covering less than half of the cylinder, the trailing slot position was found to be the most important factor as far as maximum lift coefficients were concerned. This position was near what would ordinarily be considered as the trailing edge. When the slots were equally spaced about the cylinder as with 4, 7, or 8 slots, the lift coefficient was relatively independent of slot position but these configurations resulted in lower maximum lift coefficients. At lift coefficients above 4 the lift-drag ratios of the cylinder without an end plate were approximately 80 percent of the lift-drag ratios of the cylinder with an end plate.
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