In this paper,the effect of geometries of tube open end on the shock,compression and expansion wavespropagating in the tube was investigated numerically and experimentally.One of them is a conventional straightshock t...In this paper,the effect of geometries of tube open end on the shock,compression and expansion wavespropagating in the tube was investigated numerically and experimentally.One of them is a conventional straightshock tube with an open end.The other has a divergent tail tube at the exit.Applying a divergent tail tube(flaretube)to an open end shock tube,the period of one-cycle process could be shortened and the pressure behind theexpansion wave produced at the exit of the shock tube could be lowered much more below the atmosphericpressure than that produced in the straight tube.The results suggested that the intake air into the engine wassignificantly increased by applying a flare tube instead of a straight tube.展开更多
A computational investigation has been conducted to determine the effectiveness of a passive control technique of attenuating cavity-induced pressure oscillations in a confined two-dimensional supersonic flow. The pas...A computational investigation has been conducted to determine the effectiveness of a passive control technique of attenuating cavity-induced pressure oscillations in a confined two-dimensional supersonic flow. The passive control technique is achieved by fitting two flat plates near the front wall of a square cavity at Mach number 1.83 at the cavity entrance. The results showed that the flat plates attached near the front wall of the cavity, discouraged the formation of feedback loop which is widely believed to be the reason of cavity resonance. The resultant amount of attenuation of pressure oscillations was also dependent on the length of the flat plate used as an oscillation suppressor.展开更多
文摘In this paper,the effect of geometries of tube open end on the shock,compression and expansion wavespropagating in the tube was investigated numerically and experimentally.One of them is a conventional straightshock tube with an open end.The other has a divergent tail tube at the exit.Applying a divergent tail tube(flaretube)to an open end shock tube,the period of one-cycle process could be shortened and the pressure behind theexpansion wave produced at the exit of the shock tube could be lowered much more below the atmosphericpressure than that produced in the straight tube.The results suggested that the intake air into the engine wassignificantly increased by applying a flare tube instead of a straight tube.
文摘A computational investigation has been conducted to determine the effectiveness of a passive control technique of attenuating cavity-induced pressure oscillations in a confined two-dimensional supersonic flow. The passive control technique is achieved by fitting two flat plates near the front wall of a square cavity at Mach number 1.83 at the cavity entrance. The results showed that the flat plates attached near the front wall of the cavity, discouraged the formation of feedback loop which is widely believed to be the reason of cavity resonance. The resultant amount of attenuation of pressure oscillations was also dependent on the length of the flat plate used as an oscillation suppressor.
