The Optimization of the N-Step Rocket With Different Construction Parameters and Propellant Specific Impulses in Each Stage

I t is shown in the above analysis t ha t the acoustic impedance is always a negative quant i ty . In other words, the amplitude of the reflected wave from the shock is always damped. Since the inlet is the only mechanism responsible for the instabili ty of the diffuser (3), it is obvious tha t the flow is intrinsically stable without taking consideration of viscosity and unsteadiness. Fur ther work will be published to show t h a t the viscous dissipation is responsible for the instabili ty of supersonic inlet diffusers even in a quasi-steady analysis.