Author: Tuncer Cebeci
Publisher:
ISBN:
Category :
Languages : en
Pages : 22
Book Description
The results of an investigation of boundary layers close to the stagnation point of an oscillating airfoil are reported. Two procedures for generating initial conditions - the characteristics-box scheme and a quasi-static approach - were investigated, and the quasi-static approach was shown to be appropriate provided the initial region was far from any flow separation. With initial conditions generated in this way, the unsteady boundary-layer equations were solved for the flow in the leading-edge region of a NACA 0012 airfoil oscillating from 0 degrees to 5 degrees. Results were obtained for both laminar and turbulent flow, and, in the latter case, the effect of transition was assessed by specifying its occurrence at different locations. The results demonstrate the validity of the numerical scheme and suggest that the procedures should be applied to calculation of the entire flow around oscillating airfoils. (Author).
Calculation of Boundary Layers Near the Stagnation Point of an Oscillating Airfoil
Author: Tuncer Cebeci
Publisher:
ISBN:
Category :
Languages : en
Pages : 22
Book Description
The results of an investigation of boundary layers close to the stagnation point of an oscillating airfoil are reported. Two procedures for generating initial conditions - the characteristics-box scheme and a quasi-static approach - were investigated, and the quasi-static approach was shown to be appropriate provided the initial region was far from any flow separation. With initial conditions generated in this way, the unsteady boundary-layer equations were solved for the flow in the leading-edge region of a NACA 0012 airfoil oscillating from 0 degrees to 5 degrees. Results were obtained for both laminar and turbulent flow, and, in the latter case, the effect of transition was assessed by specifying its occurrence at different locations. The results demonstrate the validity of the numerical scheme and suggest that the procedures should be applied to calculation of the entire flow around oscillating airfoils. (Author).
Publisher:
ISBN:
Category :
Languages : en
Pages : 22
Book Description
The results of an investigation of boundary layers close to the stagnation point of an oscillating airfoil are reported. Two procedures for generating initial conditions - the characteristics-box scheme and a quasi-static approach - were investigated, and the quasi-static approach was shown to be appropriate provided the initial region was far from any flow separation. With initial conditions generated in this way, the unsteady boundary-layer equations were solved for the flow in the leading-edge region of a NACA 0012 airfoil oscillating from 0 degrees to 5 degrees. Results were obtained for both laminar and turbulent flow, and, in the latter case, the effect of transition was assessed by specifying its occurrence at different locations. The results demonstrate the validity of the numerical scheme and suggest that the procedures should be applied to calculation of the entire flow around oscillating airfoils. (Author).
Calculation of Boundary Layers of Oscillating Airfoils
Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
ISBN: 9781724254054
Category :
Languages : en
Pages : 30
Book Description
A two-point finite difference unsteady laminar and turbulent boundary layer computational method was used to investigate the properties of the flow around an airfoil (NACA 0012) oscillating through angles of attack up to 18 degrees, for reduced frequencies of 0.01 and 0.20. The unsteady potential flow was determined using the unsteady potential flow method of Geissler. The influence of transition location on stal behavior was investigated, using both experimentally determined transition information, and transition located at the pressure peak; the results show the need for viscous-inviscid interaction in future computation of such flows. Cebeci, T. and Carr, L. W. Ames Research Center NASA-TM-85943, A-9599, NAS 1.15:85943, USAAVSCOM-TR-84-A-1 RTOP 505-31-32
Publisher: Createspace Independent Publishing Platform
ISBN: 9781724254054
Category :
Languages : en
Pages : 30
Book Description
A two-point finite difference unsteady laminar and turbulent boundary layer computational method was used to investigate the properties of the flow around an airfoil (NACA 0012) oscillating through angles of attack up to 18 degrees, for reduced frequencies of 0.01 and 0.20. The unsteady potential flow was determined using the unsteady potential flow method of Geissler. The influence of transition location on stal behavior was investigated, using both experimentally determined transition information, and transition located at the pressure peak; the results show the need for viscous-inviscid interaction in future computation of such flows. Cebeci, T. and Carr, L. W. Ames Research Center NASA-TM-85943, A-9599, NAS 1.15:85943, USAAVSCOM-TR-84-A-1 RTOP 505-31-32
Calculation of Boundary Layers of Oscillating Airfoils
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 34
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 34
Book Description
Prediction of Boundary-layer Characteristics of an Oscillating Airfoil
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 22
Book Description
The evolution of unsteady boundary layers on oscillating airfoils is investigated by solving the governing equations by the Characteristic Box scheme. The difficulties associated with computing the first profile on a given time-line, and the velocity profiles with partial flow reversal are solved. A sample calculation has been performed for an external velocity distribution typical of those found near the leading edge of thin airfoils. The results demonstrate the viability of the calculation procedure. (Author).
Publisher:
ISBN:
Category :
Languages : en
Pages : 22
Book Description
The evolution of unsteady boundary layers on oscillating airfoils is investigated by solving the governing equations by the Characteristic Box scheme. The difficulties associated with computing the first profile on a given time-line, and the velocity profiles with partial flow reversal are solved. A sample calculation has been performed for an external velocity distribution typical of those found near the leading edge of thin airfoils. The results demonstrate the viability of the calculation procedure. (Author).
Unsteady Turbulent Shear Flows
Author: R. Michel
Publisher: Springer Science & Business Media
ISBN: 3642817327
Category : Science
Languages : en
Pages : 445
Book Description
It was on a proposal from the "Comite National Fran.
Publisher: Springer Science & Business Media
ISBN: 3642817327
Category : Science
Languages : en
Pages : 445
Book Description
It was on a proposal from the "Comite National Fran.
Scientific and Technical Aerospace Reports
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 456
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 : 456
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.
Japanese Science and Technology, 1983-1984
Author: United States. National Aeronautics and Space Administration. Scientific and Technical Information Branch
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 1080
Book Description
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 1080
Book Description
Unsteady Aerodynamics and Aeroelasticity of Turbomachines
Author: Torsten H. Fransson
Publisher: Springer Science & Business Media
ISBN: 9401150400
Category : Science
Languages : en
Pages : 835
Book Description
Twenty-one years have passed since the first symposium in this series was held in Paris (1976). Since then there have been meetings in Lausanne (1980), Cambridge (1984), Aachen (1987), Beijing (1989), Notre Dame (1991) and Fukuoka (1994). During this period a tremendous development in the field of unsteady aerodynamics and aeroelasticity in turbomachines has taken place. As steady-state flow conditions become better known, and as blades in the turbomachine are constantly pushed towards lower weight, and higher load and efficiency, the importance of unsteady phenomena appear more clearly. th The 8 Symposium was, as the previous ones, of high quality. Furthermore, it presented the audience with the latest developments in experimental, numerical and theoretical research. More papers than ever before were submitted to the conference. As the organising committee wanted to preserve the uniqueness of the symposium by having single sessions, and thus mingle speakers and audience with different backgrounds in this interdisciplinary field, only a limited number of papers could be accepted. 54 papers were accepted and presented at the meeting, all of which are included in the present proceedings.
Publisher: Springer Science & Business Media
ISBN: 9401150400
Category : Science
Languages : en
Pages : 835
Book Description
Twenty-one years have passed since the first symposium in this series was held in Paris (1976). Since then there have been meetings in Lausanne (1980), Cambridge (1984), Aachen (1987), Beijing (1989), Notre Dame (1991) and Fukuoka (1994). During this period a tremendous development in the field of unsteady aerodynamics and aeroelasticity in turbomachines has taken place. As steady-state flow conditions become better known, and as blades in the turbomachine are constantly pushed towards lower weight, and higher load and efficiency, the importance of unsteady phenomena appear more clearly. th The 8 Symposium was, as the previous ones, of high quality. Furthermore, it presented the audience with the latest developments in experimental, numerical and theoretical research. More papers than ever before were submitted to the conference. As the organising committee wanted to preserve the uniqueness of the symposium by having single sessions, and thus mingle speakers and audience with different backgrounds in this interdisciplinary field, only a limited number of papers could be accepted. 54 papers were accepted and presented at the meeting, all of which are included in the present proceedings.
Unsteady Laminar Boundary-layer Calculations on Oscillating Configurations Including Backflow. Part 2: Airfoil in High-amplitude Pitching Motion. Dynamic Stall
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 64
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 64
Book Description
Aeronautical Engineering
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 538
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 538
Book Description