Author: Eli Reshotko
Publisher:
ISBN:
Category : Aerodynamics
Languages : en
Pages : 48
Book Description
Stability of Three-dimensional Compressible Boundary Layers
Author: Eli Reshotko
Publisher:
ISBN:
Category : Aerodynamics
Languages : en
Pages : 48
Book Description
Publisher:
ISBN:
Category : Aerodynamics
Languages : en
Pages : 48
Book Description
Stability of a three-dimensional boundary layer
Author: Jeffrey B. Morton
Publisher:
ISBN:
Category :
Languages : en
Pages : 56
Book Description
The stability of a three-dimensional boundary layer on a semi-infinite rotating cylinder at angle of attack in a uniform incompressible flow is studied. The results shed some new light on the behavior of disturbances indicating that inflection-point instability may not dominate. Numerical solution of the Orr-Sommerfeld equation is used to obtain the results and an approximate analytic solution is shown to be in good agreement with the numerical results.
Publisher:
ISBN:
Category :
Languages : en
Pages : 56
Book Description
The stability of a three-dimensional boundary layer on a semi-infinite rotating cylinder at angle of attack in a uniform incompressible flow is studied. The results shed some new light on the behavior of disturbances indicating that inflection-point instability may not dominate. Numerical solution of the Orr-Sommerfeld equation is used to obtain the results and an approximate analytic solution is shown to be in good agreement with the numerical results.
On Stability, Transition and Turbulence in Three-dimensional Boundary-layer Flows
On the Stability of Three-Dimensional Boundary Layers
Nonparallel stability of three-dimensional compressible boundary layers
Author: Nabil M. El-Hady
Publisher:
ISBN:
Category : Fluid mechanics
Languages : en
Pages : 44
Book Description
Publisher:
ISBN:
Category : Fluid mechanics
Languages : en
Pages : 44
Book Description
Linear Stability Theory and Three-Dimensional Boundary Layer Transition
Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
ISBN: 9781722341183
Category :
Languages : en
Pages : 24
Book Description
The viewgraphs and discussion of linear stability theory and three dimensional boundary layer transition are provided. The ability to predict, using analytical tools, the location of boundary layer transition over aircraft-type configurations is of great importance to designers interested in laminar flow control (LFC). The e(sup N) method has proven to be fairly effective in predicting, in a consistent manner, the location of the onset of transition for simple geometries in low disturbance environments. This method provides a correlation between the most amplified single normal mode and the experimental location of the onset of transition. Studies indicate that values of N between 8 and 10 correlate well with the onset of transition. For most previous calculations, the mean flows were restricted to two-dimensional or axisymmetric cases, or have employed simple three-dimensional mean flows (e.g., rotating disk, infinite swept wing, or tapered swept wing with straight isobars). Unfortunately, for flows over general wing configurations, and for nearly all flows over fuselage-type bodies at incidence, the analysis of fully three-dimensional flow fields is required. Results obtained for the linear stability of fully three-dimensional boundary layers formed over both wing and fuselage-type geometries, and for both high and low speed flows are discussed. When possible, transition estimates form the e(sup N) method are compared to experimentally determined locations. The stability calculations are made using a modified version of the linear stability code COSAL. Mean flows were computed using both Navier Stokes and boundary-layer codes. Spall, Robert E. and Malik, Mujeeb R. Unspecified Center ...
Publisher: Createspace Independent Publishing Platform
ISBN: 9781722341183
Category :
Languages : en
Pages : 24
Book Description
The viewgraphs and discussion of linear stability theory and three dimensional boundary layer transition are provided. The ability to predict, using analytical tools, the location of boundary layer transition over aircraft-type configurations is of great importance to designers interested in laminar flow control (LFC). The e(sup N) method has proven to be fairly effective in predicting, in a consistent manner, the location of the onset of transition for simple geometries in low disturbance environments. This method provides a correlation between the most amplified single normal mode and the experimental location of the onset of transition. Studies indicate that values of N between 8 and 10 correlate well with the onset of transition. For most previous calculations, the mean flows were restricted to two-dimensional or axisymmetric cases, or have employed simple three-dimensional mean flows (e.g., rotating disk, infinite swept wing, or tapered swept wing with straight isobars). Unfortunately, for flows over general wing configurations, and for nearly all flows over fuselage-type bodies at incidence, the analysis of fully three-dimensional flow fields is required. Results obtained for the linear stability of fully three-dimensional boundary layers formed over both wing and fuselage-type geometries, and for both high and low speed flows are discussed. When possible, transition estimates form the e(sup N) method are compared to experimentally determined locations. The stability calculations are made using a modified version of the linear stability code COSAL. Mean flows were computed using both Navier Stokes and boundary-layer codes. Spall, Robert E. and Malik, Mujeeb R. Unspecified Center ...
Stability Analysis of Three-dimensional Boundary Layers with Parabolized Stability Equations
Three-dimensional, Numerical Study of Boundary-layer Stability
Author: John W. Murdoch
Publisher:
ISBN:
Category : Boundary layer
Languages : en
Pages : 16
Book Description
Publisher:
ISBN:
Category : Boundary layer
Languages : en
Pages : 16
Book Description
Three-Dimensional Hypersonic Boundary Layer Stability and Transition
Author: Roger L. Kimmel
Publisher:
ISBN: 9781423547921
Category :
Languages : en
Pages : 83
Book Description
The stability and transition of three-dimensional boundary layers was studied. In the first phase of the investigation, arrays of hot film probes were used to measure the three-dimensional structure of instability waves on an axisymmetric cone at Mach 8. In the second phase, linear stability theory was used to design a cone with an elliptic cross section, which was also tested at Mach 8. Results show that disturbances on the axisymmetric cone travel in wave packets with predominantly zero wave angle. On the elliptic cone, only weak evidence for stationary waves was found. The predominant waves were traveling waves at about 12 kHz. Additional waves, probably second mode, occurred near 80 kHz.
Publisher:
ISBN: 9781423547921
Category :
Languages : en
Pages : 83
Book Description
The stability and transition of three-dimensional boundary layers was studied. In the first phase of the investigation, arrays of hot film probes were used to measure the three-dimensional structure of instability waves on an axisymmetric cone at Mach 8. In the second phase, linear stability theory was used to design a cone with an elliptic cross section, which was also tested at Mach 8. Results show that disturbances on the axisymmetric cone travel in wave packets with predominantly zero wave angle. On the elliptic cone, only weak evidence for stationary waves was found. The predominant waves were traveling waves at about 12 kHz. Additional waves, probably second mode, occurred near 80 kHz.
Validation of Three-dimensional Incompressible Spatial Direct Numerical Simulation Code
Author: Ronald D. Joslin
Publisher:
ISBN:
Category : Boundary layer
Languages : en
Pages : 56
Book Description
Publisher:
ISBN:
Category : Boundary layer
Languages : en
Pages : 56
Book Description