Numerical study of aerodynamic interaction of compressor and combustor flows

Numerical study of the aerodynamic interaction of transient compressor and combustor flows has been conducted using the KIVA-3V code. The simulation was based on the solution of Navier-Stokes equations with models of turbulence, sprays and chemical reactions. A typical annular combustor, including the diffuser, the secondary channels and the liner, was modeled. The transient inflow was assumed by specifying the pressure oscillation in a form of sinusoidal function. Aeroacoustic characteristics of the diffuser-liner flow were revealed. Three flow patterns, namely the quasisteady, transition and steady patterns corresponding to the frequency ranges of n ≤ 80, 80 ≤ n ≤ 320 and n ≥ 320 Hz, were classified. It is found that for the quasisteady pattern, combustion flow is in quasisteady state with flow properties dependent of time; for the steady pattern, the combustion flow can be treated as if in steady state, in which the influence of oscillation can be ignored; and the flow in the transition pattern behaves in-between. They significantly influence the gas turbine combustion.