Survival of entropy waves during their advection throughout a combustor is central to the
generation of entropic sound and the subsequent effects upon thermoacoustic stability of the …

Indirect noise generated by the acceleration of synthetic compositional and entropic
perturbations through non-isentropic nozzles is measured experimentally. A physics-based …

We investigate the low frequency transfer functions for acoustic and entropic perturbations
through nozzles and nozzle guide vanes. Previous theories rely on the isentropic …

Adverse effects of global warming due to the greenhouse gas emissions is changing the
actual paradigm for the use energy resources. In the absence of a mid-term solution for …

Entropy noise corresponds to acoustic fluctuations generated inside gas-turbine engines
when temperature (entropy) spots are accelerated by the mean flow. This type of noise …

Abstract A high-frequency (1.5 kHz) spontaneous Raman spectroscopy measurement
technique is developed and applied to measure external fluctuations generated in the local …

Entropy noise remains as a largely unexplored mechanism of combustion generated noise.
Currently, little is known about the production sources of entropy waves in flames. To …

As computational capabilities continue to grow, exploring the limits of computational fluid
dynamics to capture complex and elusive phenomena, which are otherwise difficult to study …

Combustion of hydrogen or hydrogen containing blends in gas turbines and industrial
combustors can activate thermoacoustic combustion instabilities. Convective instabilities are …

The relative importance of direct and indirect combustion noise in a realistic gas-turbine
combustor is investigated. While temperature fluctuations are commonly recognized as the …