Publications by authors named "Somnath De"

In chemical industries, multiphase flows in a bubble column reactor are frequently observed. The nonlinearity associated with bubble hydrodynamics, such as bubble-bubble and bubble-liquid interactions, gives rise to complex spatiotemporal patterns with increased gas or liquid velocities, which are extremely difficult to model and predict. In the current study, we propose a new, computationally efficient recurrence-based approach involving the angular separation between suitably defined state vectors and implement it on the experimental multiphase flow variables.

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Modern lean premixed combustors are operated in ultra-lean mode to conform to strict emission norms. However, this causes the combustors to become prone to lean blowout (LBO). Online monitoring of combustion dynamics may help to avoid LBO and help the combustor run more safely and reliably.

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Cyclones are among the most hazardous extreme weather events on Earth. In certain scenarios, two co-rotating cyclones in close proximity to one another can drift closer and completely merge into a single cyclonic system. Identifying the dynamic transitions during such an interaction period of binary cyclones and predicting the complete merger (CM) event are challenging for weather forecasters.

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Purpose: In bovine retinal pigment epithelium (RPE) cells, increased secretion of vascular endothelial growth factor (VEGF) has a positive linear association with proliferation of RPE. Spectral domain optical coherence tomography (SD-OCT) based improvement in grades of topographic retinal pigment epithelium alterations (RPE-A), were evaluated after intravitreal anti-VEGF therapy, in diabetic macular edema (DME), for the first time.

Methods: A tertiary care center-based, prospective study.

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Lean premixed combustors are highly susceptible to lean blowout flame instability, which can cause a fatal accident in aircrafts or expensive shutdown in stationary combustors. However, the lean blowout limit of a combustor may vary significantly depending on a number of variables that cannot be controlled in practical situations. Although a large literature exists on the lean blowout phenomena, a robust strategy for early lean blowout detection is still not available.

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Purpose: Cortisol, a steroid hormone, plays an essential role in metabolic processes of diabetes mellitus. This study for the first time evaluated the association of serum cortisol with spectral domain optical coherence tomography (SD-OCT)-based cross-sectional and topographic parameters with severity of diabetic retinopathy (DR).

Methods: A tertiary care center-based preliminary study was undertaken.

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Inverse diffusion flame (IDF) is a reliable low NO technology that is suitable for various industrial applications including gas turbines. However, a confined IDF may exhibit thermoacoustic instability, a kind of dynamic instability, which is characterized by catastrophically large amplitude pressure oscillations. Transition to such instability for an inverse diffusion flame is less explored compared to other types of flame.

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Background/objectives: To study the mechanism of restoration of retinal photoreceptor ellipsoid zone (EZ), after intravitreal bevacizumab (IVB) therapy, in diabetic macular oedema (DMO).

Subjects/methods: Forty-four consecutive patients aged 40-65 years having type 2 diabetes mellitus (DM) with DMO were prospectively recruited for IVB therapy. It comprised of three doses (1.

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Lean blowout (LBO) is a serious issue in modern gas turbine engines that operate in a lean (premixed) mode to follow the stringent emission norms. When an engine operates with a lean fuel-air mixture, the flame becomes unstable and is at times carried out of the combustion chamber by the unburnt flow. Thus, the sudden loss of the flame, known as lean blowout, leads to fatal accidents in aircrafts and loss of production in power plants.

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