Abstract:

ESDU 86017 gives a simple method of estimating the thrust decrement and drag increment due to the interaction of propeller flow with a body (or nacelle) at zero incidence. It applies to smoothly contoured bodies with a tractor propeller at or near the nose or a pusher propeller at or near the tail and the propellers may be counter-rotating. It applies to Mach numbers up to 80 per cent of critical for the spinner-body combination. The method predicts the propulsive thrust in terms of the shaft thrust developed to within 2 or 3 per cent of thrust. A detailed discussion of the factors affecting the interaction effects is included. A comprehensive worked example shows how the method is used in combination with the method of ESDU 83001 for the propeller free-air thrust and of ESDU 78019 for the body drag propeller-off.