Pages
- 1
- 2
- document
-
de Vries, O.H.M. (author)In dit rapport wordt de in augustus 1986 gehouden NPOC-SPOT enquête besproken. Deze enquête is gehouden in opdracht van de Beleidsconnnissie Remote Sensing (BCRS), naar aanleiding van de start van het Nationaal Remote Sensing Programma (NRSP). De enquête was bedoeld om inzicht te krijgen in de markt mogelijkheden voor EARTHNET en SPOT satelliet...report 1986
- document
- Posthuma de Boer, U. (author), de Vries, W.H. (author), Hameetman, G.J. (author), van der Wees, A.J. (author) report 1986
- document
-
de Vries, O. (author)Nadat Dr. van Holten (destijds TH-Delft) in 1974 het tipvaan windturbine concept had geformuleerd, is hieraan vanaf 1977 door de TH-Delft onderzoek verricht in het kader van het NOW. In het kader van het integrale tipvaanontwikkelingsprogramma heeft het NLR hieraan ook meegewerkt van september 1983 tot januari 1985. De inspanning van het NLR was...report 1985
- document
-
de Vries, O. (author)The commonly used blade-element theory predicts a zero yawing moment in the time-average sense. Small-scale wind-tunnel experiments at the Eindhoven University of Technology revealed stable yawing moments at almost all operating conditions with the rotor in an upwind position with respect to the tower. The present comment shows, that this...report 1984
- document
-
de Vries, O. (author)The lecture gives a review of the aspects pertaining to wind energy conversion. It starts with a short survey of different wind turhine and wind concentrator concepts. Next the aerodynamic characteristics of wind turbines are discussed. The main part of the lecture consists of a survey of the choice of the various parameters, determining a WECS,...report 1981
- document
-
de Vries, O. (author), den Blanken, M.H.G. (author)A second series of tests has been performed on a two-bladed horizontal axis wind turbine in the lowspeed wind timnel LST 3x2 of NLR. The tests have been carried out at a Reynolds number of 3.5x10 , referred to the blade chord. The investigation included the effect of turbulence on the turbine performance, the determination of the wake blockage...report 1981
- document
-
de Vries, O. (author)A two-bladed horizontal-axis wind turbine, with a diameter of 0.75 m and a solidity ratio of 0.0674, has been tested in the LST 3 x 2 of NLR. Most of the tests have been carried out at an almost constant Reynolds number of about 3.5 X 10/5. Comparison with a simple performance prediction method showed an acceptable agreement in qualitative...report 1979
- document
-
de Vries, O. (author)Some blade element theories for the calculation of the aerodynamic performstnce of a horizontal-axis wind turbine have been surveyed. With one of these theories, a parameter study has been carried out. A Cp-optimized rotor design leads to a non-linearly tapered and highly twisted rotor blade. It seems possible to simplify the blade geometry with...report 1978
- document
-
de Vries, O. (author)This report describes the theory for the calculation of the performance and the blade loading of a Darrieus wind turbine, rotating in a steady wind (rigid rotor program). A discussion of calculated results has been given. The results of the calculations, obtained with the performance theory, depend strongly on the profile data used. A future...report 1977
- document
-
de Vries, O. (author)This report deals with the contribution of NLR to the first phase of the National Research Program on Wind Energy, which consisted mainly of theoretical studies. A so-called rigid rotor computer program vjas compiled for a Darrieus wind turbine, to predict the aerodyna.mic performance of the turbine and the blade loading due to aerodynamic and...report 1977
- document
- de Vries, O. (author), Schipholt, G.J.L. (author) report 1975
- document
-
de Vries, O. (author)De energieopwekking door verschillende typen windgedreven rotoren, is aan de hand van eenvoudige TDeschcuwingen nagegaan. Het voornaamste doel was, zich te oriënteren omtrent de mogelijkheid voor het NLR om op aërodynamisch gebied "bijdragen te leveren tot de verdere ontwikkeling van deze rotoren. Verder kwam de vraag naar voren rotoren met...report 1974
- document
-
Labrujère, T.E. (author), de Vries, O. (author)The present report considers the validity of the representation of the wake by discrete trailing vortices as is common practice in potential theoretical calcualtions. Theoretical results, obtained with a method developed at NLR, are compared with experimental results obtained at NLR for a 30° swept back wing. The shape of the vortex sheet as...report 1974
- document
-
Labrujère, T.E. (author), de Vries, O. (author)The defomation of a vortex sheet behind a 30 degrees swept back wing, has been measured in a low-speed wind tunnel. The measurements included: - A total-head survey behind the wing, - Sidewash measurements across the wake, - Measurements of trailing vorticity by a vortex indicator. It has been found, that 60 percent of the trailing vorticity is...report 1974
- document
-
de Vries, O. (author)The deformation of the vortex sheet "behind a 30 sweptback wing (span 1.5 m, chord 0.3 m) has heen measured in the LST 3x2. Three types of measurements have been applied: - a total head survey (viscous wake) - yaw measurements (sidewash variation across vortex sheet) - vortex indicator measurements (vortex wake). Only a part (60%) of the total...report 1973
- document
- de Vries, O. (author) report 1973
- document
-
de Vries, O. (author)Research on high-lift devices has been carried out at NLR along the following lines. An experimental approach consisting of pressure measurements at the mid-span section of a twodimensional wing (chord about 0.6 m, span 2 m), with boundary layer control at the tunnel wallwing junctions by blowing slots. Premature flow separation can be avoided...report 1972
- document
- Labrujere, T.E. (author), Schipholt, C.J. (author), de Vries, O. (author) report 1972
- document
- Labrujere, T.E. (author), Schipholt, G.J. (author), de Vries, O. (author) report 1972
- document
-
Labrujere, T.E. (author), Schipholt, G.J. (author), de Vries, O. (author)The applicability of potential flow calculations for developing high-lift devices, is evaluated by comparing calculated pressure distributions over wing sections with trailing and leading edge high-lift devices, and experimental results, obtained during routine wind tunnel tests.report 1972
Pages
- 1
- 2