Print Email Facebook Twitter On the sound field generated by a fan in a hard-walled baffled duct with uniform flow Title On the sound field generated by a fan in a hard-walled baffled duct with uniform flow Author Laan, J.N. Schulten, J.B.H.M. Institution National Aerospace Laboratory NLR Date 1978-02-22 Abstract The present status of a method to calculate the generation, transmission and radiation of fan noise is described. A steady uniform flow is assumed in the whole field. A hard-walled circular duct is considered which is terminated at the open end by an infinite baffle. The source mechanism is the impingement of wakes from an upstream blade row giving rise to fluctuating bldde forces. This force field drives the sound field. The method is illustrated by means of numerical examples. Subject acoustic ductsacoustic propertiesmathematical modelsducted fansfar fieldsdirectivitysound propagationsound fieldsreflectionwakessound pressureturbo fansF-28 transport aircraftdensity distributionrotor blades (turbomachinery)Spey Mk-555 engineprediction analysis techniques To reference this document use: http://resolver.tudelft.nl/uuid:43dc06d7-063a-41f8-b437-cdbdb4f962eb Publisher Nationaal Lucht- en Ruimtevaartlaboratorium Access restriction Campus only Source NLR-TR 78024 U Part of collection Aerospace Engineering Reports Document type report Rights (c) 1978 National Aerospace Laboratory NLR Files campus only