Journal
ACTA ASTRONAUTICA
Volume 194, Issue -, Pages 532-543Publisher
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.actaastro.2021.11.022
Keywords
Flight safety; Nozzle; Base pressure; Pressure oscillations; Multi-block jet; Shock wave
Categories
Funding
- Ministry of Science and Higher Education of Russian Federation [FZWF-2020-0015]
Ask authors/readers for more resources
This article discusses the unsteady, transient, and oscillatory processes that occur in the nozzle devices of rocket engines. It examines the causes and mechanisms of low-frequency oscillations and identifies the design parameter ranges that ensure non-oscillating gas-dynamic flow processes.
Multi-jet interactions are characterized by a number of shock and expansion waves, formation of turbulent shear layers and subsonic recirculation zones. The problem of the occurrence of unsteady, transient and oscillatory, processes arising in the nozzle devices of rocket engines at different flight modes is discussed. The main flow regimes, the sequence of their change and qualitative patterns of shock-wave structures that arise in each of the regimes are considered. The main emphasis is paid to the causes of occurrence and mechanisms of maintenance of low-frequency oscillations of the base pressure. The regularities of changes in the amplitude-frequency characteristics of oscillations are studied depending on the main parameters of the problem. Areas of existence of oscillatory processes are found, and a search is carried out for the ranges of design parameters, geometric characteristics of nozzle assemblies that provide a non oscillating flow of gas-dynamic processes. Hysteresis phenomena of shock-wave structure at increase or decrease in the reservoir total pressure is observed.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available