Results 21 to 30 of about 176 (165)
Neural ODE to model and prognose thermoacoustic instability [PDF]
Chaos: An Interdisciplinary Journal of Nonlinear Science, 2022 Thermoacoustic instability in a reacting flow field is characterized by high amplitude pressure fluctuations driven by a positive coupling between the unsteady heat release rate and the acoustic field of the combustor. In a turbulent flow, the transition of a thermoacoustic system from a state of chaos to periodic oscillations occurs via a state of ...
Jayesh M. Dhadphale +3 more
openaire +4 more sources
Aerospace, 2021 In the present work, 3D Unsteady Reynolds-Averaged Navier-Stokes (URANS) simulations are performed to investigate the generation and mitigation mechanism of combustion-sustained thermoacoustic instabilities in a modelled swirl combustor.
Yuze Sun, Dan Zhao, Xiaowei Zhu
doaj +1 more source
Experimental Investigation of Stochastically Forced Rijke-Type Supercritical Thermoacoustic Systems
Energies, 2023 Intense thermoacoustic oscillations may lead to severe deterioration due to the induced intolerable damage to combustors. A better understanding of unstable behaviors is important to prevent or suppress these oscillations.
Hao Zhang +4 more
doaj +1 more source
loop-shaping control of azimuthal combustion instabilities in annular combustors
Journal of Low Frequency Noise, Vibration and Active Control, 2021 Lean combustion technique and annular geometries are preferred in aero-engines and gas turbines, which however may lead to azimuthal combustion instabilities. Active control can be used to stabilize combustion instabilities.
Sheng Feng, Jingxuan Li
doaj +1 more source
Monitoring Preferential Flow of Water in Sand Using Thermoacoustics Wave Imaging
Geophysical Research Letters, Volume 50, Issue 21, 16 November 2023., 2023 Abstract Accurate predictions of fluid flow, mass transport, and reaction rates critically impact the efficiency and reliability of subsurface exploration and sustainable use of subsurface resources. Quantitative dynamical sensing and imaging can play a pivotal role in the ability to make such predictions.
Chang Liu +6 more
wiley +1 more source
Metamaterial‐Augmented Head‐Mounted Audio Module
Advanced Materials Technologies, Volume 8, Issue 19, October 10, 2023., 2023 A metamaterial‐transducer resonant coupling is proposed inside a head‐mounted audio module to achieve a 3–7 dB broadband sound pressure level improvement within 50–700 Hz, which is the most challenging frequency range for radiation enhancement. The acoustic metamaterial not only enhances voltage sensitivity near the intrinsic metamaterial resonance ...
Jun Ji +5 more
wiley +1 more source
International Journal for Numerical Methods in Fluids, Volume 94, Issue 8, Page 1082-1110, August 2022., 2022 Vorticity contours in a three‐dimensional bluff‐body combustor. Abstract The objective of this study is to develop and apply efficient solution techniques for numerical modeling of combustion with stiff chemical kinetics in practical combustors. The new technique combines a fourth‐order implicit‐explicit (IMEX) additive Runge‐Kutta scheme (ARK) with ...
Joshua Christopher +2 more
wiley +1 more source
Energies, 2023 Thermoacoustic instabilities in gasturbine combustor systems can be predicted in the design phase with a thermoacoustic network model. In this model, the coupling between acoustic pressure fluctuations and the combustion rate is described by the Flame ...
Mehmet Kapucu, Jim B. W. Kok
doaj +1 more source
Advanced Control for Applications, Volume 4, Issue 2, June 2022., 2022 Abstract Predictive functional control (PFC) is a straightforward and cheap model‐based technique for systematic control of well‐damped open‐loop processes. Nevertheless, its oversimplified design characteristics are often the cause of diminished efficacy in more challenging applications; processes involving lightly damped and/or unstable dynamics have
Muhammad Saleheen Aftab +1 more
wiley +1 more source