Wall interference and support interference for the models TWIG/D750 and TWIG/NL300

Kurzfassung

Within the frame of the GARTEur working group AD AG18, the model TWIG/D750 has been built by DLR Göttingen. It is a generic fighter model, and the name TWIG means Tunnel Wall Interference Generator. The letter D then means "Deutschland", and 750 refers to the spanwidth of 750 mm. Except the scale, this model is identical with the model TWIG/NL300 - where NL means "The Netherlands" - named according to the conventions above. Force measurements have been performed with the Dutch model TWIG/NL300 in the pilot-HST, and also in the HST, in the latter case providing a set of nearly interference-free force results. The model TWIG/D750 in the test section of the TWG can not be regarded as interference-free, because of its size: the relative span is b/B = 0.750 (!). Force measurements in the adaptive test section of the TWG will be reported. The residual wall interferences are computed by making use of the DLR wall pressure method applying Green's theorem. Corrections of force data will be made according to AGARDographs 109 and 336. The influence of the support, which has been used when generating the reference data with the model TWIG/NL300 in the HST, has been investigated by using different support configurations with the model TWIG/D750 in TWG, in 1997. For the measurements, which have been performed in February 2001, the model TWIG/NL300 has been used, and three different support configurations. A comparison with the nearly interference-free results from HST is made. This work was performed within the frame of DNW research support "Analysis of TWIG wall interference measurements in TWG"