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Performance and loads of variable tip speed rotorcraft at high advance ratios.

Record Type:	Language materials, manuscript : Monograph/item
Title/Author:	Performance and loads of variable tip speed rotorcraft at high advance ratios./
Author:	Bowen-Davies, Graham M.
Description:	1 online resource (313 pages)
Notes:	Source: Dissertation Abstracts International, Volume: 76-11(E), Section: B.
Contained By:	Dissertation Abstracts International76-11B(E).
Subject:	Aerospace engineering. -
Online resource:	click for full text (PQDT)
ISBN:	9781321877090

Performance and loads of variable tip speed rotorcraft at high advance ratios.
Bowen-Davies, Graham M.

Performance and loads of variable tip speed rotorcraft at high advance ratios. - 1 online resource (313 pages)

Source: Dissertation Abstracts International, Volume: 76-11(E), Section: B.

Thesis (Ph.D.)

Includes bibliographical references

This dissertation presents a lifting-line, comprehensive approach to predicting the performance and loads of high advance ratio rotorcraft. At high advance ratios, the reverse flow region is large and its unique aerodynamics impacts the rotor performance and dynamics more than at conventional airspeeds where they are often ignored. The analysis is refined and augmented with improved modeling of the nearwake in reverse flow, a new aerodynamic model of the fuselage and the root cutout region and corrections to the airfoil properties for highly yawed flow. The analysis is correlated and evaluated against a full-scale UH-60A rotor test to an advance ratio of 1.0 and against an in-house Mach-scaled rotor to an advance ratio of 1.2. High advance ratio performance is predicted satisfactorily for both tests, including predicting the onset of thrust reversal. Despite the high advance ratio, correctly modeling the wake is most important for predicting airloads and the resulting blade bending loads, while yawed flow, nearwake inflow and the fuselage flow disturbances are important for predicting high advance ratio thrust and power. The validated analysis is used to investigate the effect of reverse flow stall, blade twist, root cut-out and shaft angle on high advance ratio performance.

Electronic reproduction.
Ann Arbor, Mich. :
ProQuest,
2018

Mode of access: World Wide Web

ISBN: 9781321877090Subjects--Topical Terms:

686400
Aerospace engineering.
Index Terms--Genre/Form:

554714
Electronic books.

Performance and loads of variable tip speed rotorcraft at high advance ratios.
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100 1 $a Bowen-Davies, Graham M. $3 1180427
245 1 0 $a Performance and loads of variable tip speed rotorcraft at high advance ratios.
264 0 $c 2015
300 $a 1 online resource (313 pages)
336 $a text $b txt $2 rdacontent
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500 $a Source: Dissertation Abstracts International, Volume: 76-11(E), Section: B.
500 $a Adviser: Inderjit Chopra.
502 $a Thesis (Ph.D.) $c University of Maryland, College Park $d 2015.
504 $a Includes bibliographical references
520 $a This dissertation presents a lifting-line, comprehensive approach to predicting the performance and loads of high advance ratio rotorcraft. At high advance ratios, the reverse flow region is large and its unique aerodynamics impacts the rotor performance and dynamics more than at conventional airspeeds where they are often ignored. The analysis is refined and augmented with improved modeling of the nearwake in reverse flow, a new aerodynamic model of the fuselage and the root cutout region and corrections to the airfoil properties for highly yawed flow. The analysis is correlated and evaluated against a full-scale UH-60A rotor test to an advance ratio of 1.0 and against an in-house Mach-scaled rotor to an advance ratio of 1.2. High advance ratio performance is predicted satisfactorily for both tests, including predicting the onset of thrust reversal. Despite the high advance ratio, correctly modeling the wake is most important for predicting airloads and the resulting blade bending loads, while yawed flow, nearwake inflow and the fuselage flow disturbances are important for predicting high advance ratio thrust and power. The validated analysis is used to investigate the effect of reverse flow stall, blade twist, root cut-out and shaft angle on high advance ratio performance.
533 $a Electronic reproduction. $b Ann Arbor, Mich. : $c ProQuest, $d 2018
538 $a Mode of access: World Wide Web
650 4 $a Aerospace engineering. $3 686400
650 4 $a Mechanical engineering. $3 557493
655 7 $a Electronic books. $2 local $3 554714
690 $a 0538
690 $a 0548
710 2 $a ProQuest Information and Learning Co. $3 1178819
710 2 $a University of Maryland, College Park. $b Aerospace Engineering. $3 1148546
773 0 $t Dissertation Abstracts International $g 76-11B(E).
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3711468 $z click for full text (PQDT)