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Ducted Fan Efficiency and Noise
SAE Technical Paper Series, 2005<div class="htmlview paragraph">NACA reports from the 1950s and more recently developed CFD codes are used to define features necessary for the creation of an efficient ducted fan system. Sources of ducted fan noise are identified and methods to minimize that noise are outlined. The connection between efficiency and noise is detailed.</div>
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A note on the performance of ducted fans
Aeronautical Quarterly, 1953SummaryThe strip-theory equations of flow through a ducted fan were the basis of a method of designing a fan for a given performance. The merit of the method was that it amounted to an explicit solution of the design problem, no iteration being necessary.In the inverse problem, of determining the flow past a given fan in conditions other than those of ...
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Propagation of Fan Noise in Cylindrical Ducts
The Journal of the Acoustical Society of America, 1971The propagation of random sound in a cylindrical duct has been treated theoretically. The conditions under which the simple wave equation applies to the transmission of sound generated by industrial air-moving devices is made explicit. The acoustic forcing function and termination conditions are discussed extensively as well as the structure of the ...
Ulrich Bolleter, Robert C. Chanaud
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Anti-Corrosion Methods and Materials, 1957
‘It's an ill wind that blows nobody any good,’ says the old adage, and a case in point is that of polyvinylchloride, a thermoplastic material with great corrosion resistance which, although produced in the laboratory nearly 100 years ago, has only been of commercial importance since the last war. In the manufacture of any fan the emphasis is on design.
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‘It's an ill wind that blows nobody any good,’ says the old adage, and a case in point is that of polyvinylchloride, a thermoplastic material with great corrosion resistance which, although produced in the laboratory nearly 100 years ago, has only been of commercial importance since the last war. In the manufacture of any fan the emphasis is on design.
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Prediction of tonal ducted fan noise
Journal of Sound and Vibration, 2016Abstract This study introduces an analytical model aiming at predicting the tonal acoustic sources generated and radiated by the rotor–stator interaction in a fan stage. This model is able to cope with complex three-dimensional stator geometries and it fully accounts for cascade effects, characteristic of modern fan stages.
J. de Laborderie, S. Moreau
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Nondimensional Modeling of Ducted-Fan Aerodynamics
Journal of Aircraft, 2012The unique aerodynamic nature of the ducted-fan configuration makes it difficult to represent in terms of traditional nondimensional coefficients. Analysis of wind-tunnel data for an axisymmetric generic ducted-fan configuration has led to a new nondimensional modeling scheme. Force coefficients are plotted versus advance ratio for a range of angles of
Osgar John Ohanian +2 more
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Ducted Fan VTOL for Working Platform
SAE Technical Paper Series, 1991<div class="htmlview paragraph">Making use of advantages of ducted fan, i.e. compactness and approachability, ducted fan VTOL can be used for many purposes, such as construction and servicing of the tall structures, rescue, etc.. In this paper the development of a working platform which utilizes the ducted fan VTOL concept is tried.
Shohei Niwa, Masayuki Suzuki
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AFT FAN DUCT ACOUSTIC RADIATION
Journal of Sound and Vibration, 1998A finite element code has been developed for the prediction of the radiated acoustic field from the aft fan duct of a turbofan engine. The acoustic field is modelled based on the assumption that the steady flow in and around the nacelle is irrotational as is the acoustic perturbation.
W. Eversman, D. Okunbor
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Analysis on the Influence of Duct Casing Geometry on the Performance of a Ducted Fan
MesinThis paper aims to evaluate the influence of an electric ducted fan’s (EDF) geometry on its performance through parameter correlation analysis. Sample data was first built by generating new EDF models with varying duct casing geometries through optimal space-filling (OSF) sampling method. Afterwards, each model was numerically solved with computational
Marcellino Pangaribuan, Firman Hartono
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A technique for shape optimization of ducted fans
2018Ducted fans have found renewed interest particularly in the field of micro aerial vehicles. The complex flow interactions between the rotor, shroud and nacelle hinder the design of optimal lifting duct shapes. Further, the optimum duct shape changes with freestream velocity and rotor configuration.
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