Computational investigations of the coupling between transient flame dynamics and thermo-acoustic instability in a self-excited resonance combustor

An approximate analytical model for the frequency response of evaporating droplets under a mixed feeding regime

“…The parameter γ denotes the constant isentropic coefficient, while the latent heat of vaporization per unit mass of the liquid is given by ℓ = bRT 2 S /M F (T S − c) 2 , with R standing for the universal gas constant.…”

“…These instabilities result from the coupling between acoustic waves and combustion. In confined devices, the coupling between acoustic field and heat or mass release at certain frequency levels may lead to engine failure or other catastrophic consequences [1,2]. On the contrary, new blends of fuels can be engineered to undergo preferential instabilities leading to homogeneous combustion with higher efficiency [3].…”

Modelling of pulsating inverted conical flames: a numerical instability analysis

“…A coupled FDF with a neural network thermoacoustic approach, over an LES model of a turbulent and partially premixed flame led to the prediction of combustion instability limit cycle oscillations [21]. By applying steady flamelet model and the flamelet/progress variable approach, a computational analysis of the coupling of transient flame dynamics was effected, such as the local extinction and the thermoacoustic instability, in self-excited resonance combustor, enabling the identification of mechanisms of thermoacoustic instability [22]. Recent studies on the FTF in premixed flame dynamics analyzed the significant impact of the flame geometry into its acoustic response [23], and modeled the premixed flame linear dynamics in terms of time delays [24], thus characterizing an acoustically compact flame by its impulse response, enabling for the development or control techniques in the combustion and thermoacoustic domain.…”

Drop vaporization frequency response: an approximate analytical solution for mixed injection regimes

“…Combustion instabilities result from the coupling between acoustic waves and combustion. In confined devices, the coupling between acoustic field and heat or mass release at certain frequency levels may lead to engine failure or other catastrophic consequences [1,2]. On the contrary, new blends of fuels can be engineered to undergo preferential instabilities leading to homogeneous combustion with higher efficiency [3].…”