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Daryl L. Bonhaus

Bio: Daryl L. Bonhaus is an academic researcher from Langley Research Center. The author has contributed to research in topics: Airfoil & Aerodynamics. The author has an hindex of 8, co-authored 14 publications receiving 1419 citations.

Papers
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Journal ArticleDOI
TL;DR: An implicit, Navier-Stokes solution algorithm is presented for the computation of turbulent flow on unstructured grids using an upwind algorithm and a backward-Euler time-stepping scheme.

838 citations

Journal ArticleDOI
TL;DR: An implicit code for computing inviscid and viscous incompressible flows on unstructured grids is described and results are compared with an exact solution for theInviscid flow over a four-element airfoil.

304 citations

Journal ArticleDOI
TL;DR: In this paper, an aerodynamic design algorithm for turbulent flow using unstructured grids is described, which is based on an implicit formulation in which the turbulence model is fully coupled with the e ow equations when solving for the costate variables.
Abstract: An aerodynamic design algorithm for turbulent e ows using unstructured grids is described. The current approachusesadjoint (costate)variablestoobtainderivativesofthecostfunction.Thesolutionoftheadjointequations is obtained by using an implicit formulation in which the turbulence model is fully coupled with the e ow equations when solving for the costate variables. The accuracy of the derivatives is demonstrated by comparison with e nite difference gradients, and a few sample computations are shown. Recommendations on directions of further research into the Navier ‐Stokes design process are made. Nomenclature A = area of control volume a = speed of sound C ¤ = constant used in Sutherland’ s law for viscosity cb1;cb2;cv1; = constants used in Spalart ‐Allmaras cw1;cw2;cw3 turbulence model cd = drag cl = lift c1

183 citations

Proceedings ArticleDOI
11 Jan 1999
TL;DR: In this paper, the authors present a table of Table of Table 1.1.2.3.1 and Table 2.4.1, Table 3.2, 2.
Abstract: ii Acknowledgments iv Table of

53 citations


Cited by
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Journal ArticleDOI
TL;DR: The aim of this paper is to present the reader with a perspective on how JFNK may be applicable to applications of interest and to provide sources of further practical information.

1,803 citations

Journal ArticleDOI
TL;DR: An introduction to the subject, emphasising the simplicity of the ideas when viewed in the context of linear algebra, and examples of the use of adjoint methods for optimising the design of business jets are presented.
Abstract: Optimal design methods involving the solution of an adjoint system of equations are an active area of research in computational fluid dynamics, particularly for aeronautical applications. This paper presents an introduction to the subject, emphasising the simplicity of the ideas when viewed in the context of linear algebra. Detailed discussions also include the extension to p.d.e.'s, the construction of the adjoint p.d.e. and its boundary conditions, and the physical significance of the adjoint solution. The paper concludes with examples of the use of adjoint methods for optimising the design of business jets.

1,004 citations

Journal ArticleDOI
TL;DR: An implicit, Navier-Stokes solution algorithm is presented for the computation of turbulent flow on unstructured grids using an upwind algorithm and a backward-Euler time-stepping scheme.

838 citations

Journal ArticleDOI
TL;DR: The resulting integrated SWAN + ADCIRC system is highly scalable and allows for localized increases in resolution without the complexity or cost of nested meshes or global interpolation between heterogeneous meshes.

514 citations

Journal ArticleDOI
TL;DR: In this paper, a continuous adjoint approach for obtaining sensitivity derivatives on unstructured grids is developed and analyzed, and a second-order accurate discretization method is described.

466 citations