an experimental investigation on cowl lip's open process of two-dimensional inlet
- Paper number
IAC-08.C4.5.13
- Author
Mr. Dinghua Feng, National University of Defense Technology, China
- Coauthor
Prof. Hua Li, National University of Defense Technology, China
- Year
2008
- Abstract
Currently, many experimental studies of hypersonic two-dimensional inlet are carried out by fixing inlet’s cowl lip in advance. One experimental measurement is corresponding one state of inlet. But this method does not meet the actual flight. During the flight, the aircraft’s inlet suffers a dynamic process from closed to open. In order to simulate the actual process of inlet’s work and research its characteristic, a direct-connect wind tunnel was designed, which could simulate the incoming flow with high Mach number 5.3. In the experiments, three different experimental devices were made. They were used to research a group of two-dimensional inlets which had different internal contraction ratios. The cowl lip could be rotated by a facility from closed to open during the experiments. The pressure distributed on the inlet wall and schlieren pictures of the inlet’s flow field were gotten during lip’s open process. By analyzing the experimental data, it can be found that the continuous change of internal contraction ratios had great effect on inlet’s starting characteristic. The boundary layer on the forebody as well as had effect on inlet’s starting characteristic. The following are some results and conclusions. (1) The flow field near the lip has complex structure during the lip’s open process. When the cowl lip is closed or near the inlet’s wall, there are significant interactions between the overflow shock wave and the boundary layer. With the cowl lip gradually opening, the pressure near the front lip decreases. When the internal contraction ratio is about 1.0, the shock wave induced by the separation of boundary layer becomes weak and vanishes very soon. (2) On the base of that the wind tunnel normally works, different internal contraction ratios have great effect on the characteristic of inlet starting. In a certain flow condition and with the same aspect ratio, the shock wave in the inlet becomes weak along with internal contraction ratios decreases. The flow field structure tends to be simple, and this is available for inlet starting.
- Abstract document
- Manuscript document
IAC-08.C4.5.13.pdf (🔒 authorized access only).
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