Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 44
Book Description
Viscous Effect on Airfoils for Unsteady Transonic Flows
Author: Calculation of Viscous Effects on Transonic Flow for Oscillating Airfoils and Comparisons with Experiment
Author: James T. HowlettUnsteady Transonic Aerodynamic and Aeroelastic Calculations about Airfoils and Wings
Author: Calculation of Unsteady Transonic Flows with Mild Separation by Viscous-inviscid Interaction
Author: James T. HowlettPublisher:
ISBN:
Category : Aerodynamics, Transonic
Languages : en
Pages : 44
Book Description
Unsteady Viscous Thin Airfoil Theory
Author: J. E. YatesPublisher:
ISBN:
Category : Aerodynamic load
Languages : en
Pages : 24
Book Description
During the last three years considerable progress has been made in the prediction of unsteady airloads on profiles in transonic flow, but prediction is still limited to potential inviscid flow. New analytical developments, and comparison with experimental results, need the introduction of the coupling between the inviscid flow and the boundary layer. Dr Yates, in this publication, proposes an original approach to the problem which permits a first calculation of boundary layer effects. He derives a new kernel of the lifting surface integral equation which takes into account shear flow effects in the boundary layer.
Calculation of Viscous Effects on Transonic Flow for Oscillating Airfoils and Comparisons with Experiment
Author: James T. HowlettPublisher:
ISBN:
Category : Aerodynamics, Transonic
Languages : en
Pages : 84
Book Description
Experimental Studies of Scale Effects on Oscillating Airfoils at Transonic Speeds
Author: Steady Inviscid Transonic Flows Over Planar Airfoils
Author: R. MagnusPublisher:
ISBN:
Category : Aerodynamics, Transonic
Languages : en
Pages : 68
Book Description
A finite difference procedure based upon a system of unsteady equations in proper conservation form with either exact or small disturbance steady terms is used to calculate the steady flows over several classes of airfoils. The airfoil condition is fulfilled on a slab whose upstream extremity is a semi-circle overlaying the airfoil leading edge circle. The limitations of the small disturbance equations are demonstrated in an extreme example of a blunt-nosed, aft-cambered airfoil. The necessity of using the equations in proper conservation form to capture the shock properly is stressed. Ability of the steady relaxation procedures to capture the shock is briefly examined.
Calculation of Unsteady Transonic Flows with Mild Separation by Viscous-Inviscid Interaction
Author: National Aeronautics and Space Adm NasaPublisher:
ISBN: 9781729430842
Category :
Languages : en
Pages : 44
Book Description
This paper presents a method for calculating viscous effects in two- and three-dimensional unsteady transonic flow fields. An integral boundary-layer method for turbulent viscous flow is coupled with the transonic small-disturbance potential equation in a quasi-steady manner. The viscous effects are modeled with Green's lag-entrainment equations for attached flow and an inverse boundary-layer method for flows that involve mild separation. The boundary-layer method is used stripwise to approximate three-dimensional effects. Applications are given for two-dimensional airfoils, aileron buzz, and a wing planform. Comparisons with inviscid calculations, other viscous calculation methods, and experimental data are presented. The results demonstrate that the present technique can economically and accurately calculate unsteady transonic flow fields that have viscous-inviscid interactions with mild flow separation. Howlett, James T. Langley Research Center RTOP 509-10-02-03...
Author: Dennis L. Huff