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These wind tunnel tests were performed at the boundary layer wind tunnel of the Danish Maritime Institute as part of the test program with the cylindrical enclosure selected for the VLT (cf. section 4.1.3). The model included the same complete enclosure with a fully modeled telescope inside it at a scale of 1:64 (see fig. gif). The tests were run with several venting configurations of the enclosure as described in section 4.1.3 above and covered the range of wind directions 0, 10, 20, 40, 90 and 180 in combination with telescope zenith angles of 10, 35 and 60.

Two types of measurements were performed:

Appendix gif includes sketches with the location of the measurement points and tables with the means, minima, maxima and rms of all pressure coefficients and wind speed measurements close to the mirror surface measured. The measured rms of the pressure coefficients are plotted in fig. gif versus the azimuth with the wind direction for different telescope altitudes and enclosure configurations.


Lorenzo Zago,, Sun Feb 26 22:57:31 GMT+0100 1995