Accession Number : ADA194003
Title : An Assessment of the Drag Reduction Properties of Riblets and the Penalties of Off-Design Conditions.
Descriptive Note : Memorandum rept.,
Corporate Author : ROYAL AIRCRAFT ESTABLISHMENT FARNBOROUGH (ENGLAND)
Personal Author(s) : Gaudet, L
PDF Url : ADA194003
Report Date : Aug 1987
Pagination or Media Count : 22
Abstract : An assessment is given of the performance of riblets in reducing skin friction in turbulent flow. The data of Sawyer and Winter is used to develop skin-friction relationships derived from the velocity profile for a turbulent boundary layer as modified by a riblet surface. The maximum percentage drag reduction is shown to vary with Reynolds number R sub x. At large values of the non-dimensional riblet height the riblet surface acts as a uniform roughness and a value for the equivalent sand-grain roughness height is given. Examples of the estimated drag reductions which might be achieved for two current aircraft by incorporating riblet surfaces are presented.
Descriptors : *DRAG REDUCTION, *TURBULENT BOUNDARY LAYER, AIRCRAFT, ESTIMATES, PENALTIES, PROFILES, REYNOLDS NUMBER, SURFACE ROUGHNESS, SKIN FRICTION, TURBULENT FLOW, VELOCITY, RIBS, GREAT BRITAIN
Subject Categories : Aerodynamics
Distribution Statement : APPROVED FOR PUBLIC RELEASE