Search
CSV
RISAcoustic Damper Placement and Tuning for Annular Combustors: An Adjoint-Based Optimization Study
Publisher: The American Society of Mechanical Engineers (ASME)
Abstract: Thermoacoustic instabilities pose a major threat to modern gas turbines. The use of acoustic dampers, like Helmholtz resonators, has proven useful for the mitigation of such instabilities. However, assessing the effect of ...
Analysis of Thermoacoustic Modes in Can-Annular Combustors Using Effective Bloch-Type Boundary Conditions
Publisher: The American Society of Mechanical Engineers (ASME)
Abstract: Heavy-duty gas turbines are commonly designed with can-annular combustors, in which all flames are physically separated. Acoustically, however, the cans communicate via the upstream located compressor plenum or at the ...
Swirl Flame Response to Simultaneous Axial and Transverse Velocity Fluctuations
Publisher: The American Society of Mechanical Engineers (ASME)
Abstract: In this experimental study, we investigate the impact of transverse acoustic velocity fluctuations on flame response to axial velocity fluctuations. Such a scenario where a flame is under the influence of a 2D acoustic ...
Efficient Computation of Thermoacoustic Modes in Industrial Annular Combustion Chambers Based on Bloch Wave Theory
Publisher: The American Society of Mechanical Engineers (ASME)
Abstract: Most annular combustors feature a discrete rotational symmetry so that the full configuration can be obtained by copying one burnerflame segment a certain number of times around the circumference. A thermoacoustic model ...
An Acoustic Time-of-Flight Approach for Unsteady Temperature Measurements: Characterization of Entropy Waves in a Model Gas Turbine Combustor
Publisher: The American Society of Mechanical Engineers (ASME)
Abstract: Lean premixed combustion promotes the occurrence of thermoacoustic phenomena in gas turbine combustors. One mechanism that contributes to the flame–acoustic interaction is entropy noise. Fluctuations of the equivalence ...
Methods for the Calculation of Thermoacoustic Stability Boundaries and Monte Carlo-Free Uncertainty Quantification
Publisher: The American Society of Mechanical Engineers (ASME)
Effects of Asymmetry on Thermoacoustic Modes in Annular Combustors: A Higher-Order Perturbation Study
Publisher: The American Society of Mechanical Engineers (ASME)
Abstract: Gas-turbine combustion chambers typically consist of nominally identical sectors arranged in a rotationally symmetric pattern. However, in practice, the geometry is not perfectly symmetric. This may be due to design ...
Effects of Nonlinear Modal Interactions on the Thermoacoustic Stability of Annular Combustors
Publisher: The American Society of Mechanical Engineers (ASME)
Abstract: In this theoretical and numerical analysis, a low-order network model is used to investigate a thermoacoustic system with discrete rotational symmetry. Its geometry resembles that of the MICCA combustor (Laboratoire EM2C, ...
A Non-Compact Effective Impedance Model for Can-to-Can Acoustic Communication: Analysis and Optimization of Damping Mechanisms
Publisher: The American Society of Mechanical Engineers (ASME)
Abstract: Can-annular combustors can feature azimuthal instabilities even if the acoustic coupling between the individual cans is weak. Recently, various studies have focused on modeling the acoustic communication between adjacent ...
Effect of an Azimuthal Mean Flow on the Structure and Stability of Thermoacoustic Modes in an Annular Combustor Model With Electroacoustic Feedback
Publisher: The American Society of Mechanical Engineers (ASME)
Abstract: Thermoacoustic oscillations in axisymmetric annular combustors are generally coupled by degenerate azimuthal modes, which can be of standing or spinning nature. Symmetry breaking due to the presence of a mean azimuthal ...