Spectra signals of gas pressure pulsations in annular and linear dual-slotted nozzles

ABSTRACT

Complex results in experimental and numerical flow dynamics research and spectra signals of gas pressure pulsations in annular and linear dual-slotted nozzles are presented. Experiments are performed in a pulsed aerodynamic setup using acetylene–air mixture combustion products as working gas. Viscous flow calculations are based on the Navier–Stokes equations for multicomponent reactive gaseous medium using single-temperature chemical nonequilibrium model. As a result, the frequency Fourier spectrum of pressure pulsation at the thrust wall center is determined. Typical pulsed pressure signals obtained in the calculations and detected in the experiments are presented.

KEYWORDS:

• Annular (linear dual-slotted) nozzle
• Navier–Stokes equations
• Fourier spectrum
• Pressure pulsations
• Dominant frequency
• 2-Stage PDE

Acknowledgment

The investigations were carried out according to research plan of the Institute of Mechanics of Lomonosov Moscow State University, investigations were partially (in experimental part) financially supported by the Grant of the Ministry of Education and Science of the Russian Federation (Contract No. 14.G39.31.0001 of 13.02.2017) and (in calculation part) by Grants of Russian Foundation for Basic Research (projects No 16-29-01092 and No 18-01-00883).