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Accession Number ADA567215
Title Viability of Cross-Flow Fan with Helical Blades for Vertical Take-off and Landing Aircraft.
Publication Date Sep 2012
Media Count 70p
Personal Author H. L. Kwek
Abstract The cross-flow fan (CFF) is a lifting and propulsion device that retains the advantages of a fixed-wing aircraft by using a ducted lift fan. There is no upper limit to the rotor length-to-diameter ratio of a CFF, allowing the device to be installed along the length of the wing or lifting device. The CFF discharged vector can be easily rotated about the fan axis since the fan has no angular requirements, further allowing the capability of vertical take-off and landing (VTOL) by thrust vectoring. CFF possess the potential to propel an airframe to flight; however, adequate thrust must be produced by the CFF for it to realize VTOL. Conventional CFF designs with straight blades produce unacceptable noise levels for personal air vehicle operation. It is believed that helical blades could solve the sound pressure- level problem and produce more thrust to aid VTOL. Using computational fluid dynamics (CFD) software, ANSYS-CFX, a three-dimensional (3-D) straight-bladed model was validated against a previous study's experimental results. A 3-D model with helical blades was constructed to investigate the performance. The analytical results have shown that helical blades could increase the thrust performance of a CFF, and could possibly realize VTOL.
Keywords Ansys-cfx computer program
Ansys-workbench simulation package
Computational fluid dynamics
Computerized simulation
Cross flow
Cross-flow fans
Ducted fans
Fan blades
Helical blades
Lift fans
Noise reduction
Sound pressure
Straight blades
Three dimensional
Three-dimensional models
Thrust vectoring
Vertical landings
Vertical take-off and landing aircraft
Vertical takeoff aircraft
Vtol(Vertical take-off and landing)

Source Agency Non Paid ADAS
NTIS Subject Category 51C - Aircraft
41J - Tooling, Machinery, & Tools
46B - Fluid Mechanics
81A - Combustion & Ignition
Corporate Author Naval Postgraduate School, Monterey, CA. Dept. of Mechanical and Aerospace Engineering.
Document Type Thesis
Title Note Master's thesis.
NTIS Issue Number 1308
Contract Number N/A

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