Development of a Method for Predicting the Performance and Stresses of VTOL-type Propellers

Development of a Method for Predicting the Performance and Stresses of VTOL-type Propellers PDF Author: Andrew Richard Trenka
Publisher:
ISBN:
Category : Rotors (Helicopters)
Languages : en
Pages : 134

Get Book Here

Book Description
The report presents a theoretical method which allows the prediction of performance and stress characteristics of a single VTOL-type of propeller-wing-nacelle combination operating in various flight conditions from hovering through transition and into axial flight. The method includes (1) the effects of a distorted wake, i. e., the effects of contraction and radial and axial velocity variations; (2) the effects of hovering close to the ground; (3) the interference effects from a nacelle and wing buried in the propeller slipstream. Also presented are experimental thrust and torque data. However, because of the insufficient accuracy of the experimental data collected, no definite evaluation of the model is made. (Author).

Development of a Method for Predicting the Performance and Stresses of VTOL-type Propellers

Development of a Method for Predicting the Performance and Stresses of VTOL-type Propellers PDF Author: Andrew Richard Trenka
Publisher:
ISBN:
Category : Rotors (Helicopters)
Languages : en
Pages : 134

Get Book Here

Book Description
The report presents a theoretical method which allows the prediction of performance and stress characteristics of a single VTOL-type of propeller-wing-nacelle combination operating in various flight conditions from hovering through transition and into axial flight. The method includes (1) the effects of a distorted wake, i. e., the effects of contraction and radial and axial velocity variations; (2) the effects of hovering close to the ground; (3) the interference effects from a nacelle and wing buried in the propeller slipstream. Also presented are experimental thrust and torque data. However, because of the insufficient accuracy of the experimental data collected, no definite evaluation of the model is made. (Author).

Performance and Stresses Obtained on an Isolated VTOL-type Propeller Operating in Hovering, Transitional and Axial Flight

Performance and Stresses Obtained on an Isolated VTOL-type Propeller Operating in Hovering, Transitional and Axial Flight PDF Author: Andrew R. Trenka
Publisher:
ISBN:
Category : Propellers
Languages : en
Pages : 206

Get Book Here

Book Description
Experimental performance and blade stresses measured on a three-bladed VTOL-type propeller tested in free air are presented. The isolated propeller was tested over ranges of prop speed, forward velocity, blade angle setting, and thrust axis to free-stream angle. Correlation with a theoretical method of predicting propeller performance and blade stresses was made. It was found that when the propeller was operating in a flight condition for which the theory was developed, correlation between theory and experiment was good. When the propeller was operating in a flight condition where very small positive or negative effective angles of attack were encountered, correlation between theory and experiment was poor. (Author).

Scientific and Technical Aerospace Reports

Scientific and Technical Aerospace Reports PDF Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 978

Get Book Here

Book Description


Technical Abstract Bulletin

Technical Abstract Bulletin PDF Author:
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 712

Get Book Here

Book Description


Government-wide Index to Federal Research & Development Reports

Government-wide Index to Federal Research & Development Reports PDF Author:
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 732

Get Book Here

Book Description


Predictive Methods for the Dynamic Response of a Quad Tilt-duct V/STOL Aircraft in Transition

Predictive Methods for the Dynamic Response of a Quad Tilt-duct V/STOL Aircraft in Transition PDF Author: Irving Carl Statler
Publisher:
ISBN:
Category : Short take-off and landing aircraft
Languages : en
Pages : 466

Get Book Here

Book Description


Wakes of Lifting Propellers (rotors) in Ground Effect

Wakes of Lifting Propellers (rotors) in Ground Effect PDF Author: F. A. DuWaldt
Publisher:
ISBN:
Category : Rotors (Helicopters)
Languages : en
Pages : 110

Get Book Here

Book Description
The report presents the development of a wake model for a lifting propeller (rotor) in ground effect and the computational procedure used to determine the spacial distribution of wake vorticity and the induced velocity field accompanying that vorticity distribution. Sample calculations for a two-bladed rotor were carried out on an IBM 7044 computer. Locations of wake vortical elements and the associated induced velocities at selected field points are presented for advance ratios of 0, 0.02, 0.05, and 0.10 for an H/R (ratio of rotor height above ground to rotor radius) of 1.0. Also, a few results for a hovering case with H/R = 0.5 are presented. A calculated root-mean-square velocity map is compared with measured hovering data (time averaged) and good agreement is obtained in the outer half of the slipstream. The implications of computed results with respect to the flow field at a horizontal stabilizer or tail rotor are noted as examples of the use of the model. The wake vortex model used for these calculations is a distorted continuous helix emanating from each blade tip. (Author).

U.S. Government Research & Development Reports

U.S. Government Research & Development Reports PDF Author:
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 928

Get Book Here

Book Description


Government Reports Annual Index

Government Reports Annual Index PDF Author:
Publisher:
ISBN:
Category : Government reports announcements & index
Languages : en
Pages : 1018

Get Book Here

Book Description


The National Union Catalogs, 1963-

The National Union Catalogs, 1963- PDF Author:
Publisher:
ISBN:
Category : American literature
Languages : en
Pages : 812

Get Book Here

Book Description