Author: Joe F Thompson (Jr)
Publisher:
ISBN:
Category :
Languages : en
Pages : 95
Book Description
Experimental evidence of the existence of a stagnation line between the leading and trailing edges on the outer surface of the shroud of a shrouded propeller in the static condition, in rearward motion, and in forward motion is presented. This stagnation line on the outer surface, which is a result of viscous interaction between the propeller slipstream and the external flow, causes a reduction in shroud circulation below that calculated by distributed singularities methods which assume a stagnation line at the trailing edge only. Shroud thrust decreases as the distance between this stagnation line and the trailing edge increases. It is shown that in rearward motion, such as is the case for a VTOL aircraft landing, the stagnation line moves forward from the vicinity of the trailing edge to the vicinity of the leading edge as vehicle speed increases. This forward movement of the stagnation line results in a significant loss in thrust, which can be correlated with the stagnation line location. Shroud pressure distribution, stagnation line location, and shroud thrust are presented for all three cases of motion at several propeller pitch angles, propeller rotational speeds, and vehicle linear speeds. It is shown that the flow pattern about the shroud is rather complicated in rearward motion, involving two coaxial ring-vortices surrounding the shroud. (Author).
An Experimental Investigation of the Effect of Forward and Rearward Motion on the Thrust of a Shrouded Propeller
Author: Joe F Thompson (Jr)
Publisher:
ISBN:
Category :
Languages : en
Pages : 95
Book Description
Experimental evidence of the existence of a stagnation line between the leading and trailing edges on the outer surface of the shroud of a shrouded propeller in the static condition, in rearward motion, and in forward motion is presented. This stagnation line on the outer surface, which is a result of viscous interaction between the propeller slipstream and the external flow, causes a reduction in shroud circulation below that calculated by distributed singularities methods which assume a stagnation line at the trailing edge only. Shroud thrust decreases as the distance between this stagnation line and the trailing edge increases. It is shown that in rearward motion, such as is the case for a VTOL aircraft landing, the stagnation line moves forward from the vicinity of the trailing edge to the vicinity of the leading edge as vehicle speed increases. This forward movement of the stagnation line results in a significant loss in thrust, which can be correlated with the stagnation line location. Shroud pressure distribution, stagnation line location, and shroud thrust are presented for all three cases of motion at several propeller pitch angles, propeller rotational speeds, and vehicle linear speeds. It is shown that the flow pattern about the shroud is rather complicated in rearward motion, involving two coaxial ring-vortices surrounding the shroud. (Author).
Publisher:
ISBN:
Category :
Languages : en
Pages : 95
Book Description
Experimental evidence of the existence of a stagnation line between the leading and trailing edges on the outer surface of the shroud of a shrouded propeller in the static condition, in rearward motion, and in forward motion is presented. This stagnation line on the outer surface, which is a result of viscous interaction between the propeller slipstream and the external flow, causes a reduction in shroud circulation below that calculated by distributed singularities methods which assume a stagnation line at the trailing edge only. Shroud thrust decreases as the distance between this stagnation line and the trailing edge increases. It is shown that in rearward motion, such as is the case for a VTOL aircraft landing, the stagnation line moves forward from the vicinity of the trailing edge to the vicinity of the leading edge as vehicle speed increases. This forward movement of the stagnation line results in a significant loss in thrust, which can be correlated with the stagnation line location. Shroud pressure distribution, stagnation line location, and shroud thrust are presented for all three cases of motion at several propeller pitch angles, propeller rotational speeds, and vehicle linear speeds. It is shown that the flow pattern about the shroud is rather complicated in rearward motion, involving two coaxial ring-vortices surrounding the shroud. (Author).
An Experimental Investigation of the Effect of Forward and Rearward Motion on the Thrust of a Shrouded Propeller
Author: Joe F. Thompson
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Scientific and Technical Aerospace Reports
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 1008
Book Description
Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 1008
Book Description
Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Technical Abstract Bulletin
Author:
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 912
Book Description
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 912
Book Description
Experimental Investigation of the Effects of Some Shroud Design Variables on the Static Thrust Characteristics of a Small-scale Shrouded Propeller Submerged in a Wing
Author: Robert T. Taylor
Publisher:
ISBN:
Category : Airplanes
Languages : en
Pages : 710
Book Description
An experimental investigation has been made to determine the effects of shroud-lip radius of curvature, shroud length, and shroud diffuser angle on the static thrust characteristics of a small-scale shrouded propeller which simulated a propeller submerged in the wing of an airplane. Also included are the effects of distance from the exit of the shroud to the ground on the thrust available take-off.
Publisher:
ISBN:
Category : Airplanes
Languages : en
Pages : 710
Book Description
An experimental investigation has been made to determine the effects of shroud-lip radius of curvature, shroud length, and shroud diffuser angle on the static thrust characteristics of a small-scale shrouded propeller which simulated a propeller submerged in the wing of an airplane. Also included are the effects of distance from the exit of the shroud to the ground on the thrust available take-off.
Ducted Fan Design: Volume 1 - Propulsion Physics and Design of Fans and Long-Chord Ducts
Author: Marc de Piolenc
Publisher: Lulu.com
ISBN: 0359104908
Category : Technology & Engineering
Languages : en
Pages : 182
Book Description
Presents a simplified method of designing ducted fans for light aircraft propulsion. Includes a survey of ducted-fan-powered aircraft, ranging from amateur-built airplanes to military models and prototypes. Detailed discussion of engines and list of suitable powerplants drawn from automobiles, ATVs and personal watercraft. Extensive technical bibliography and list of sources.
Publisher: Lulu.com
ISBN: 0359104908
Category : Technology & Engineering
Languages : en
Pages : 182
Book Description
Presents a simplified method of designing ducted fans for light aircraft propulsion. Includes a survey of ducted-fan-powered aircraft, ranging from amateur-built airplanes to military models and prototypes. Detailed discussion of engines and list of suitable powerplants drawn from automobiles, ATVs and personal watercraft. Extensive technical bibliography and list of sources.
Government-wide Index to Federal Research & Development Reports
Author:
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 1078
Book Description
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 1078
Book Description
An Experimental Investigation of a Circulation Controlled Shrouded Propeller
Author: Jeffrey Clayton Ashworth
Publisher:
ISBN:
Category : Propellers, Aerial
Languages : en
Pages : 113
Book Description
A preliminary experimental investigation was made on a 14.18 inch inside diameter, ten inch long, symmetrical airfoil shaped shroud equipped with blowing slots on a blunt semicircular trailing edge. The purpose of the investigation was to determine the effect of circulation control on the thrust of the shroud-propeller combination. Static tests were performed at three propeller blade pitch angles, three propeller speeds and three levels of inside slot blowing rates. Data recorded consisted of the propeller thrust and torque, shroud static pressures, total pressure in front of the inside struts, and total pressure at the blowing slot. Static pressure data was reduced to coefficient form and integrated to obtain thrust and normal force coefficients. This was converted to pounds and compared with the propeller thrust.
Publisher:
ISBN:
Category : Propellers, Aerial
Languages : en
Pages : 113
Book Description
A preliminary experimental investigation was made on a 14.18 inch inside diameter, ten inch long, symmetrical airfoil shaped shroud equipped with blowing slots on a blunt semicircular trailing edge. The purpose of the investigation was to determine the effect of circulation control on the thrust of the shroud-propeller combination. Static tests were performed at three propeller blade pitch angles, three propeller speeds and three levels of inside slot blowing rates. Data recorded consisted of the propeller thrust and torque, shroud static pressures, total pressure in front of the inside struts, and total pressure at the blowing slot. Static pressure data was reduced to coefficient form and integrated to obtain thrust and normal force coefficients. This was converted to pounds and compared with the propeller thrust.
Hovering Craft & Hydrofoil
Author:
Publisher:
ISBN:
Category : Ground-effect machines
Languages : en
Pages : 388
Book Description
Publisher:
ISBN:
Category : Ground-effect machines
Languages : en
Pages : 388
Book Description
Experimental Investigation of the Effects of Some Shroud Design Variables on the Statis Thrust Characteristics of a Small-scale Shrouded Propeller Submerged in a Wing
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 23
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 23
Book Description