Results 11 to 20 of about 787,947 (227)

Dynamics of Thermoacoustic Oscillations in Swirl Stabilized Combustor without and with Porous Inert Media

Journal of Combustion, 2022
Lean premixed (LPM) combustion processes are of increased interest to the gas turbine industry due to their reduction in harmful emissions. These processes are susceptible to thermoacoustic instabilities, which are produced when energy added by an in ...
Cody Dowd, Joseph Meadows
doaj   +2 more sources

Emerging topics in nanophononics and elastic, acoustic, and mechanical metamaterials: an overview. [PDF]

Nanophotonics, 2023
Abstract This broad review summarizes recent advances and “hot” research topics in nanophononics and elastic, acoustic, and mechanical metamaterials based on results presented by the authors at the EUROMECH 610 Colloquium held on April 25–27, 2022 in Benicássim, Spain.
Krushynska AO, Torrent D, Aragón AM, Ardito R, Bilal OR, Bonello B, Bosia F, Chen Y, Christensen J, Colombi A, Cummer SA, Djafari-Rouhani B, Fraternali F, Galich PI, Garcia PD, Groby JP, Guenneau S, Haberman MR, Hussein MI, Janbaz S, Jiménez N, Khelif A, Laude V, Mirzaali MJ, Packo P, Palermo A, Pennec Y, Picó R, López MR, Rudykh S, Serra-Garcia M, Sotomayor Torres CM, Starkey TA, Tournat V, Wright OB.   +34 more
europepmc   +2 more sources

Generation and Mitigation Mechanism Studies of Nonlinear Thermoacoustic Instability in a Modelled Swirling Combustor with a Heat Exchanger

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, Yuanhao Wang, Xinyan Li, Geng Chen, Yuze Sun   +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, Xu Mao, Chang Wang, Rebecca Liyanage, Juan Heredia Juesas, Ruben Juanes, Jose Angle Martinez‐Lorenzo   +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, Chuming Zhao, Frank Yao, Tetsuro Oishi, John Stewart, Yun Jing   +5 more
wiley   +1 more source

Effects of Hydrogen Enrichment on Thermoacoustic and Helical Instabilities in Swirl Stabilised Partially Premixed Flames

Flow Turbulence and Combustion, 2023
The effects of hydrogen enrichment on flame and flow dynamics of a swirl-stabilised partially premixed methane-air flame are studied using large eddy simulation.
Ankit D. Kumar, J. Massey, I. Boxx, N. Swaminathan   +3 more
semanticscholar   +1 more source

High‐order implicit‐explicit additive Runge–Kutta schemes for numerical combustion with adaptive mesh refinement

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, Stephen M. Guzik, Xinfeng Gao   +2 more
wiley   +1 more source

CFD-Based Prediction of Combustion Dynamics and Nonlinear Flame Transfer Functions for a Swirl-Stabilized High-Pressure Combustor

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