Combustion instability modeling using multi-mode flame transfer functions and a nonlinear Euler solver

Multi-Fidelity Framework for Modeling Combustion Instability

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Equilibrium condition nonlinear modeling of a cracked concrete beam using a 2D Galerkin finite volume solver

A constitutive model based on two–dimensional unstructured Galerkin finite volume method (GFVM) is introduced and applied for analyzing nonlinear behavior of cracked concrete structures in equilibrium condition. The developed iterative solver treats concrete as an orthotropic nonlinear material and considers the softening and hardening behavior of concrete under compression and tension by using...

Combustion instability due to the nonlinear interaction between sound and flame

Nonlinear Combustion Instability Data Reduction

A crucial element in the practical solution of combustion instability problems in rocket motor development programs is the accurate interpretation of data secured in pulsed motor stability testing. There presently exist no universally accepted or wellestablished methods for carrying out this type of data analysis. Most investigators apply only linear combustion instability theory; any attempted...

Combining a Helmholtz solver with the flame describing function to assess combustion instability in a premixed swirled combustor

Limit cycles of combustion instabilities can be estimated by studying the nonlinear behavior of flame dynamics. In the present study the flame describing function (FDF) framework is combined with a linear acoustic Helmholtz solver in order to estimate the growth rate of the acoustic perturbations in a swirled combustor. It is assumed that when this growth rate equals the inherent dissipation of...