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Experimental investigation of rotor/stator interaction noise generation, acoustic mode measurements

Zandbergen, T. (author)

An experimental investigation was carried out in the low speed wind tunnel LST to study aircraft engine noise generation by rotor/stator interaction. Reported is a follow-up experiment including detailed acoustic measurements in the duct downstream of a rotor with cylindrical pins to complement earlier tests whereby rotor wake velocities and...

report 1987

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Experimental investigation of rotor/stator interaction noise generation. Model description and aerodynamic measurements

Zandbergen, T. (author)

An experimental investigation was carried out to study aircraft engine noise generation by rotor/stator interaction. The experiment was designed to enable a first step verification of a theoretical fan noise model and to indicate further developments which may be needed to provide a representative acoustic field modelling for engine duct liner...

report 1987

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Voorstel voor experimenteel onderzoek aan het geluid van een geïsoleerde propeller

Zandbergen, T. (author)

report 1984

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Propeller noise measurements inf DNW on the fuselage of a twin engine aircraft model

Zandbergen, T. (author), Sarin, S.L. (author), Donnelly, R.P. (author)

Results of sound pressure measurements on the fuselage wall of a twin engine propeller driven model are presented. The tests were carried out in the German-Dutch low speed wind tunnel DNW in the Netherlands. The model was equipped with either metallic propeller blades or composite blades. The propeller diameter was 0.762 m. Six microphones were...

report 1984

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Voorstel voor experimenteel ondezoek fan-lawaai

Zandbergen, T. (author), de Wolf, W.B. (author), Schulten, J.B.H.M. (author)

report 1983

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In-flight acoustic measurements in the engine intake of a Fokker F28 aircraft

Zandbergen, T. (author), Sarin, S.L. (author), Laan, J.N. (author), Zeemans, H.J. (author)

Acoustic measurements were carried out in the engine intake ducts of a Fokker F28 aircraft during flight. One of the two tail-mounted, low by-pass ratio engines having a hard-walled intake was instrumented to determine the amplitudes of the circumferential modes which constitute the sound field. In the other engine the impedance of the inlet...

report 1983

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On the practical use of a three-microphone technique for in-situ acoustic impedance measurements on double layer flow duct liners

Zandbergen, T. (author)

A three-microphone technique is presented for in-situ acoustic impedance measurements on double layer liners of the Helmholtz resonator type. It can be used under conditions of flow and arbitrary noise sources. The emphasis of this paper is the practical application of this technique, including microphone installation and the implications of...

report 1981

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The NLR/NGTE joint programme on the measurement of attenuation and impedance in acoustic flow duct facilities.

Zandbergen, T. (author), Martlew, D.L. (author)

The National Aerospace Laboratory NLR in the Netherlands and the National Gas Turbine Establishment NOTE operate similar acoustic flow duct facilities but with differences in their respective approaches to the measurement of attenuation and impedance of duct linings. A joint exercise was arranged with the object of comparing methods and results,...

report 1981

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Evaluation of Levinsky's method for the calculation of the lift distribution on a wing in propulsive jets

Zandbergen, T. (author), Maarsingh, R.A. (author)

Based on comparison with results from special experiments, an evaluation has been performed of the method of Levinsky, Thommen, Yager and Holland, which is intended to calcxilate the spanwise lift distribution on wings immersed in propulsive jets. Various modifications of the original method have been investigated. It was found that the method,...

report 1979

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Are locally reacting acoustic liners always behaving as they should?

Zandbergen, T. (author)

The properties of a Helmholtz resonator type acoustic lining material may he seriously affected by intercellular water drain holes. This was shown by experiments in the NLR flow duct facility on an actual aircraft engine liner where drain holes caused a considerable shift in the frequency for maximum attenuation. Furthermore the drain holes...

report 1979

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Experimental investigation of the aerodynamic characteristics of a wing propulsion jets

Zandbergen, T. (author), Maarsingh, R.A. (author), Joosen, C.J.J. (author)

With the intent to test the qualities of the theoretical models used in two different calculation methods, pressure distributions have been measured on a simple half model wing-in-jet combination. The position of the jets relative to the wing was varied, mainly in a plane perpendicular to the span. Jet velocities of 1, 2 and 3 times the tunnel...

report 1977

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Experimental investigation of round turbulent jets in a cross flow

Zandbergen, T. (author), Joosen, C.J.J. (author)

report 1974

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Application of Levinsky's method to wings with defelected slipstreams

Zandbergen, T. (author), de Boer, E. (author)

A computer program written in Fortran IV and based on the method of Levinsky has been developed for the calculation of the spanwise lift distribution on wings with deflected slipstreams. This report gives a description of Levinsky's method and detailed information on the computer program. Results of computations are compared with experimental...

report 1972

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On the applicability of a new version of lifting surface theory to non-slender and kinked wings

Labrujere, E. (author), Zandbergen, P.J. (author)

Results are presented which are obtained by a new elaborate method developed at NLR for the determination of the characteristics of thin wings in subsonic flow. Attention is paid to the rate of convergence of the numerical solutions, especially with respect to the number of collocation points. Two rectangular wings have been treated in order to...

report 1971

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A survey of ten years of NLR activities on ringwing-body configurations (1956-1966)

Erdmann, S.F. (author), Zandbergen, P.J. (author)

report 1969

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An application of the N-strip method of integral relations for analyzing the flow around a circular cone

Zandbergen, P.J. (author), Baurdoux, H.I. (author)

The solution of sets of non-linear partial differential equations using the method of integral relations is considered. Emphasis is laid on the derivation of a general N-strip approximation algorithm. In order to check the applicability of this algorithm a program has been written to obtain the solution of the flow field around a circular cone...

report 1968

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A new approach to the numerical solution of the equation of subsonic lifting surface theory

Zandbergen, P.J. (author), Labrujere, Th.E. (author), Wouters, J.G. (author)

The present report deals with the numerical treatment of the linearised lifting surface theory through a method which is based upon the representation of the pressure distribution on chordwise direction by a series of Chebyshew polynomials according to Laschka, and upon the determination of the spanwise integral involved by means of...

report 1967

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Beschouwingen over de rol van drukverdelings-berekeningsmethoden bij de vormgeving van vliegtuigvleugels voor hoog-subsone snelheden

Loeve, W. (author), Zandbergen, P.J. (author)

In this paper, a discussion is given of some of the aerodynamic difficulties involved in the design of wings for high-subsonic speeds, and of the theoretical methods available to calculate sub-critical pressure distributions. It appears that until now only one of these methods, being in fact a semi-emperical one, is developed far enough to be of...

report 1966

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The behaviour of the wave drag coefficient of a certain optimum body in off–design conditions.

Baurdour, H.I. (author), Zandbergen, P.J. (author)

In this report the drag-coefficient of an optimum body with a conical nose has been determined. The body was designed for a Mach number of the undisturbed stream equal to 3. It is found that the curve for the drag coefficient shows a definite kink at the design Mach number. The conclusion is reached that a more general approach for designing...

report 1964

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Optimum shape of a body revolution with base drag at supersonic speed

van der Walle, F. (author), Raat, J. (author), Zandbergen, P.J. (author)

In this report a method is presented to determine optimum shapes of bodies of revolution taking into account the shape dependent part of the base drag. The latter is achieved by using the Chapman assumption that the base pressure coefficient, when correlated with conditions at a suitable point near the base, depends only on the free-stream Mach...

report 1964