Feasibility study on the design of a laminar flow nacelle

This paper describes the design of a laminar flow nacelle using numerical flow methods. With an appropriate contouring of the nacelle, natural laminar flow is maintained up to 60 % of the nacelle length at cruise flight conditions. The drag reduction that is obtained if a transport aircraft is equipped with two laminar flow nacelles instead of conventional turbulent nacelles is estimated at delta C index D = 0.0011. The behaviour of the laminar flow nacelle is also investigated for takeoff and landing conditions.It is found that the inlet of the new nacelle is not more sensitive to flow separation than conventional nacelles.