On the response of a lean-premixed hydrogen combustor to acoustic and dissipative-dispersive entropy waves

State prediction of an entropy wave advecting through a turbulent channel flow

“…This formulation requires a fluid dynamics simulation to provide the two-dimensional flow field inside the nozzle. Recently, Fattahi et al (2019) extended the compact analysis to include the annihilating effects due to hydrodynamics, heat transfer, and flow stretch upon the nozzle response. Nevertheless, since these works were primarily concerned with the conversion of entropy waves into sound in a nozzle, the upstream evolution of entropy waves was not investigated.…”

A comprehensive investigation of acoustic power level in a moderate or intense low oxygen dilution in a jet-in-hot-coflow under various working conditions

“…The results showed that the non-compact nozzle theory is necessary to accurately capture phase-cancellation effects between entropy and composition noise, and the linearized Euler formulation is required to account for complex mode shapes of the perturbations exiting the combustor and entering the downstream nozzle. The entropy dispersion effects on the combustion noise level of a combustor and turbine outlet were studied by Mahmoudi et al [34] and Fattahi and co-workers [35][36][37]. They reported that entropy dispersion is an important factor to increase the level of noise emission in turbines and nozzles.…”

Large eddy simulation of pseudo shock structure in a convergent–long divergent duct

“…Over the past decade, large-eddy simulation (LES) has emerged as a promising alternative for prediction of turbulent flows behavior. This methodology is currently being applied to a wide variety of engineering applications, including combustion [20][21][22][23][24][25][26][27], simulations of the wind turbine [28], acoustics [29][30][31][32], combustion noise [33,34] and several studies of SBLI [35,36]. To illustrate, Koo and Raman [37] applied the dynamic Smagorinsky subgrid model for supersonic inlet of an isolator and they found that this model is suitable for capturing the large-scale features of the unstart process.…”