Sensitivity and nonlinearity of thermoacoustic oscillations
MP Juniper, RI Sujith - Annual Review of Fluid Mechanics, 2018 - annualreviews.org
Nine decades of rocket engine and gas turbine development have shown that
thermoacoustic oscillations are difficult to predict but can usually be eliminated with …
thermoacoustic oscillations are difficult to predict but can usually be eliminated with …
Adjoint methods as design tools in thermoacoustics
L Magri - Applied Mechanics Reviews, 2019 - asmedigitalcollection.asme.org
In a thermoacoustic system, such as a flame in a combustor, heat release oscillations couple
with acoustic pressure oscillations. If the heat release is sufficiently in phase with the …
with acoustic pressure oscillations. If the heat release is sufficiently in phase with the …
Optimal eddy viscosity for resolvent-based models of coherent structures in turbulent jets
Response modes computed via linear resolvent analysis of a turbulent mean-flow field have
been shown to qualitatively capture characteristics of the observed turbulent coherent …
been shown to qualitatively capture characteristics of the observed turbulent coherent …
Resolvent-based modeling of coherent wave packets in a turbulent jet
Coherent turbulent wave-packet structures in a jet at Reynolds number 460 000 and Mach
number 0.4 are extracted from experimental measurements and are modeled as linear …
number 0.4 are extracted from experimental measurements and are modeled as linear …
Single-and double-helix vortex breakdown as two dominant global modes in turbulent swirling jet flow
In this paper, we study the shape and dynamics of helical coherent structures found in the
flow field of an annular swirling jet undergoing vortex breakdown. The flow field is studied by …
flow field of an annular swirling jet undergoing vortex breakdown. The flow field is studied by …
Origin of the synchronous pressure fluctuations in the draft tube of Francis turbines operating at part load conditions
The synchronous pressure surge effect is a critical phenomenon occurring in Francis
turbines operating at part load conditions. In this regime, pressure fluctuations are …
turbines operating at part load conditions. In this regime, pressure fluctuations are …
A weakly nonlinear analysis of the precessing vortex core oscillation in a variable swirl turbulent round jet
K Manoharan, M Frederick, S Clees… - Journal of Fluid …, 2020 - cambridge.org
We study the emergence of precessing vortex core (PVC) oscillations in a swirling jet
experiment. We vary the swirl intensity while keeping the net mass flow rate fixed using a …
experiment. We vary the swirl intensity while keeping the net mass flow rate fixed using a …
Experimental study of transient mechanisms of bistable flame shape transitions in a swirl combustor
M Stöhr, K Oberleithner… - … of Engineering for …, 2018 - asmedigitalcollection.asme.org
Sudden changes of flame shape are an undesired, yet poorly understood feature of swirl
combustors used in gas turbines. The present work studies flame shape transition …
combustors used in gas turbines. The present work studies flame shape transition …
Forcing statistics in resolvent analysis: application in minimal turbulent Couette flow
An analysis of the statistics of the nonlinear terms in resolvent analysis is performed in this
work for turbulent Couette flow at Reynolds number 400. Data from a direct numerical …
work for turbulent Couette flow at Reynolds number 400. Data from a direct numerical …
Stability and optimal forcing analysis of a wind turbine wake: Comparison with POD
Understanding the dynamics and generation of coherent structures in wind-turbine wakes is
crucial for efficiency improvement of wind farms, which will most probably represent one of …
crucial for efficiency improvement of wind farms, which will most probably represent one of …