Research On The Design And Regulation Of Wide Applicability Inlet For RBCC Power

Rocket Based Combined Cycle(RBCC) engine is one of the most key propulsion technology for the new Reusable Launch Vehicle.It has a huge martial and commercial application foreground.Inlet should operate over a wide range of Mach numbers as the important part of RBCC engine.It brings a great challenge for design them.According to the wide working range of Ma2~6,an investigation for 2D and 3D sidewall compression variable geometry inlets of RBCC were carried out.Firstly, the researches about serial type and over/under type of 2D inlet were developed.Variable-ramps with translational cowl wall and rotating cowl wall were applied to the serial type inlet.The scheme of translational cowl wall is competent to gain high mass flow rate and high throat pressure coefficient during the whole working range Ma2~6 by using third shock on lip mode.However,the latter one cannot satisfy the adjusting requirements.But their mass flow rate all reach to 0.70 at Ma3.0.In order to improve the seal and cool condition at the variable geometry throat section at high Mach number,an over/under type inlet was discussed.Through adjusting the shunt board and the low-speed throat height,the mass flow rate of the inlet reaches to 0.70 or over it. Researches indicate : when Ma are 2.0~3.0, the characteristics of the two passages are similar.While the characteristic of the low-speed passage is lower than high-speed passage as a result of thick boundary layer at Ma 3.5.Basing on the 3D sidewall compression RBCC inlet,the research about rotating the second ramp and translating the top plate of isolation was investigated. The parametric researches about self-starting performance were discussed.Basing on the results,the initial inlet was designed.During the low Mach number range, the inlet was used bleeding slot to accomplish self-start at Ma?2.5.When at Ma4.0~6.0,the mass flow rate of the inlet reaches to 0.80 or over it.Additionally,an extension research on the translational cowl wall of 2D serial type inlet that applied to the working range of Ma2~8 and attack angle 0°~8° was studied and the variable geometry scheme is proved to be effective preliminarily.