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Hoeijmakers, H.W.M. (author)
An analysis is presented of results of a computational method to simulate the steady compressible vortical type of flow around a 65-deg sharp-edged cropped delta wing. The discussion emphasizes some more fundamental aspects of the numerical simulation such as the separation of the flow, the structure of the leading-edge vortex core and the flow...
report 1991
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Hoeijmakers, H.W.M. (author)
The physical aspects, the mathematical modeling, the development and application of computational methods for the simulation of vertical flows are described. The high-Reynolds number vortex flows considered are assumed to be steady, sub-critical and such that the structure of the flow is well-ordered and consists of thin shear layers and slender...
report 1989
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Hoeijmakers, H.W.M. (author)
A survey Is presented of several aspects of the use and further development of panel methods in aerodynamics. Aspects discussed include possible types of boundary conditions, low versus higher-order formulations, simulation of subsonic and supersonic flow and modeling of wakes as well as of leading-edge vortex separation. Also discussed are...
report 1987
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de Bruin, A.C. (author), Hoeijmakers, H.W.M. (author)
Laminar and turbulent boundary layer calculations were carried out on the leeward side of a flat sharp-edged delta wing. The prediction of laminar-turbulent boundary layer transition and the prediction of secondary separation are addressed in some detail.
report 1986
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Hoeijmakers, H.W.M. (author)
In this lecture methods are discussed for the numerical simulation of vortical type of flows. The various methods in use at present are discussed in some detail, primarily with a view towards three-dimensional steady flow applications such as vortex wakes and leading-edge vortex flows. Some of the computational aspects of the numerical...
report 1986
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Hoeijmakers, H.W.M. (author)
Activities in the Netherlands in the area of simulating low-speed flows using vortex elements are summarized. Aspects of some of the methods developed are highlighted and plans for future work are indicated.
report 1986
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Hoeijmakers, H.W.M. (author)
In part I of this report a method is described for computing the incompressible flow about slender, thin wings with leading-edge vortex separation. It is assumed that both the wing and the flow field are symmetric with respect to the x—z plane. The method can handle delta—like wings of quite general planform and shape. However, in the...
report 1986
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Hoeijmakers, H.W.M. (author), Verhaagen, N.G. (author)
Modem aircraft configurations derive their highangle-of-attack capabilities to a large extent from the separation induced vortex flow from leading and side edges. In this paper theoretical and experimental investigations into vortex flow aerodynamios are described. Emphasis is placed on the description of the flow over slender highly swept wings...
report 1985
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Hoeijmakers, H.W.M. (author)
In this report an approximate method is described for computing, through the unsteady analogy, the shape of steady vortex wakes downstream of aircraft configurations in steady flight. In the analogy the steady fully three-dimensional problem is reduced to a two-dimensional timedependent problem, corresponding to the evolution of a two...
report 1985
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Hoeijmakers, H.W.M. (author)
In Part I if this report a method is described for approximately computing the shape of the steady vortex wake downstream of an aircraft configuration in steady flight through the unsteady analogy. In the analogy the steady fully three-dimensional problem is reduced to a two-dimensional time-dependent problem, corresponding to the evolution of a...
report 1985
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Hoeijmakers, H.W.M. (author), Rizzi, A. (author)
The numerical solution for the inviscid incompressible flow about a 70-deg swept delta wing at 20 deg incidence is considered. Two solutions are presented and compared in detail. The first solution is obtained employing a free-vortex-sheet panel method that solves for the potential flow with "fitted" vortical flow regions. This type of method is...
report 1984
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Hoeijmakers, H.W.M. (author)
A review is presented of computational methods to simulate the aerodynamics of configurations with leading-edge vortex flow. The various methods in use at present are discussed in some detail, primarily with a view towards three-dimensional steady flow applications. The strengths and weaknesses of the methods are indicated and results of...
report 1984
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Hoeijmakers, H.W.M. (author)
This lecture discusses methods for the numerical solution of vortical type of flows about wings. The various methods are discussed primarily with a view toward three-dimensional subsonic steady flow applications. The lecture is meant to give some insight into the weakness, strengths and prospects of the different methods. The various methods in...
report 1983
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Hoeijmakers, H.W.M. (author)
A review is presented of computational methods for the determination of the characteristics of vortical type flows occurring in aircraft aerodynamics. The review covers primarily computational methods for computing the downstream development of vortex wakes and methods for computing the characteristics of configurations with leading-edge and...
report 1983
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Hoeijmakers, H.W.M. (author)
A panel method (NLRAERO) is described for the computation of the velocity and pressure distribution of complex configurations in linearized subsonic and supersonic flow. The configurations that can be dealt with may consist of any number of slender and pointed body-like components and any number of thin and mildly cambered lifting components. It...
report 1982
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Hoeijmakers, H.W.M. (author), Vaatstra, W. (author), Verhaagen, N.G. (author)
An experimental and theoretical investigation is described of the flow above and downstream of a 76° delta wing and two double-delta wings (sweep 76°/60° and 76°/40°, respectively, kink at 50 % chord). The flow pattern is visualized employing a laser-light-sheet technique. For the case of the delta wing experimental results are compared with...
report 1982
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Hoeijmakers, H.W.M. (author), Vaatstra, W. (author)
The paper describes a computational method for two-dimensional vortex sheet motion in incompressible flow. The procedure utilizes a second-order panel method, an adaptive panel scheme and a concept for treating highly rolled-up portions of the vortex sheet. Results are presented for the roll-up of the wake behind an elliptically loaded wing, a...
report 1981
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Hoeijmakers, H.W.M. (author), Vaatstra, W. (author)
For the limiting cases of conical flow about delta wings and time dependent 2-D development of the wake behind the trailing edge of wings a new second-order panel method is described. It is demonstrated that the panel method is stable for the mixed design/analysis boundary conditions characterizing both problems. The method for following 2-D...
report 1981
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Hoeijmakers, H.W.M. (author)
Characteristics of three second-order and two third-order panel method formulations for the incompressible flow about a flat plate at incidence are investigated. The second order methods employ quadratic representations for the doublet distribution, either based on quadratic B-splines or on a combination of a Taylor series expansion and finite...
report 1981
document
Hoeijmakers, H.W.M. (author)
A panel method has been developed for the computation of the velocity and pressure distribution and the aerodynamic characteristics of complex configurations in linearized subsonic or supersonic flow. A computer code has been developed to perform the calculations. The configuration may consist of any number of bodies as fuselage, tiptanks, pods,...
report 1981
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