| Summary: | 碩士 === 國立成功大學 === 航空太空工程學系 === 88 === The purpose of this study is to investigate the aerodynamic characteristics of the ogive-cylinder by means of visualization at high angle of attack with lateral jet. Furthermore, the pressure sensitive paint (PSP) technique for measuring pressure distribution on aerodynamic surfaces was studied. This experiment includes three parts. (1) By means of a dye-injection method employed in a water channel and the flow region of the separated vortex sheets was studied. Applying the paint-dots method showed the limiting streamline and separation line pattern on the model surface. The steady asymmetric vortex flow was realized as the key phenomenon that causes the side force of the ogive-cylinder. (2) The colored Schlieren method was employed to study shock and vortex sheets. The color difference was revealed from the flow image, in which very large density gradients are present. The test mach numbers were 0.78, 0.86 and 0.96, and the corresponding Reynolds number are , and . The ogive-cylinder was inclined from 00 to 500 with a jet’s issuing from the leeward side. The strength of the vortex sheets was influenced with angle of attack, jet and shock position. (3) The calibration of PSP versus pressure and temperature has been accomplished in this study. Initially, the oxygen quenching was proved in blow tests with the O2 and N2. Finally, using a laser to excite the paint while collecting the fluorescence by a photo-multiplier tube enabled the intensity measurement made in various pressure and temperature conditions in the calibration chamber.
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