年間 6 号発行
ISSN 印刷: 2150-766X
ISSN オンライン: 2150-7678
Indexed in
CFD ANALYSES OFLOW FREQUENCYCOMBUSTION INSTABILITYIN SOLID PROPELLANT ROCKET MOTORS
要約
The characteristics of low frequency, bulk-mode combustion instability in solid rocket motors with high-speed internal flow were studied numerically by solving the nonlinear Euler’s equation coupled with an unsteady nonlinear combustion equation of solid propellant. Then, the results were compared with those obtained by the so-called L* burner equations, which assumes the uniformity of all physical quantities in the combustion chamber. The linear stability boundaries obtained by both calculations agreed fairly well if the steady-state pressure difference between fore and aft ends in the combustion chamber is taken into account. When the steady-state operating point is near the stability boundary in the unstable region, a small oscillation grows first and then shifts to a limit cycle. On the other hand, when it is far away from the boundary, the oscillation grows until temporary extinction occurs. Frequencies of the L* oscillation obtained by the CFD agreed well with those of the L* burner equations.