Stability analysis of thermo-acoustic nonlinear eigenproblems in annular   combustors. Part II. Uncertainty quantification
  Monte Carlo and Active Subspace Identification methods are combined with first- and second-order adjoint sensitivities to perform (forward) uncertainty quantification analysis of the thermo-acoustic stability of two annular combustor configurations. This method is applied to evaluate the risk factor, i.e., the probability for the system to be unstable. It is shown that the adjoint approach reduces the number of nonlinear-eigenproblem calculations by up to $\sim\mathcal{O}(M)$, as many as the Monte Carlo samples. 
Luca Magri, Michael Bauerheim, Franck Nicoud and Matthew Juniper
physics.flu-dyn