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Showing 1 to 15 of 15 for “"Turbulent Reacting Flows"”.
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Conditional source-term estimation methods for turbulent reacting flows
… methods are used to obtain chemical closure in turbulent combustion simulation. A Laminar Flamelet Decomposition (LFD) and then a Trajectory Generated Low-Dimensional Manifold (TGLDM) method are combined with CSE in Reynolds-Averaged Navier Stokes (RANS) simulation of non-premixed autoigniting …
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Unstructured mesh - finite volume algorithms for swirling, turbulent, reacting flows
… code which is capable of solving swirling, turbulent fluid flow and reactive, radiative heat transfer on highly complex geometries. Specifically the techniques are applied to the simulation of processes occurring in the direct smelting of iron. The use of the Finite Volume method makes it …
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A dual-junction thermocouple probe for compensated temperature measurement in reacting flows
… and temporally resolved temperature data in turbulent reacting flows. Such a system would allow for increased understanding of turbulent reacting flows without the need for a costly and complex optical system. The system under study uses the responses of two thermocouples of different sizes …
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Determination of Flame Dynamics for Unsteady Combustion Systems using Tunable Diode Laser Absorption Spectroscopy
… a priori. CFD simulations of full-scale, turbulent, reacting flows remain unrealizable. The work in this paper is part of a study that focuses on developing compact models of TA instabilities, i.e. acoustics and flame dynamics. Flame dynamics are defined as the response in heat release to …
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Large eddy simulation of premixed combustion using flamelets
… has potential to address unsteady phenomena in turbulent premixed flames and to capture turbulence scales and their influence on combustion. Thus, this approach is gaining interest in industry to analyse turbulent reacting flows. In LES, the dynamics of large-scale turbulent eddies down to a …
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Modeling The Evolution Of Vehicle Exhaust Plume Near Road And In Laboratory Dilution Systems Using The Ctag Model
… development and applications of an environmental turbulent reacting flow model, the Comprehensive Turbulent Aerosol Dynamics and Gas Chemistry (CTAG) model. CTAG is designed to simulate the transport and transformation of multiple air pollutants in various environments. For near-road applications, …
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Advancing turbulent reacting flow simulations with generalisable machine learning models for sub-grid FDF
The accurate modelling of turbulent reacting flows remains a significant challenge in computational combustion research, particularly within the large eddy simulation (LES) framework. This study investigates the application of machine learning (ML) techniques for predicting sub-grid filtered …
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Statistical description of turbulent reacting media
… the interaction of chemistry and turbulence in a turbulent reacting flow. Both self-ignition and flame propagation are studied. For self-ignition study, the combined effects of temperature/concentration inhomogeneities and turbulence were studied numerically. For this purpose two statistic …
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Large eddy simulations of hydrogen/methane jets in crossflows under engine-relevant conditions
… While the fundamental fluid dynamics of non-reacting JICF have been extensively studied, a detailed understanding of hydrogen combustion in these flows, especially under practical high-pressure conditions, remains limited. Moreover, the transitional development of hydrogen-methane blends …
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Experimental Investigation of Flow and Wall Heat Transfer in an Optical Combustor for Reacting Swirl Flows
… better understanding of combustion in swirl flows and thermal energy transfer from the turbulent reacting flows to solid surfaces. Therefore, accurate measurement and prediction of the flows and heat loads are indispensable. This dissertation presents flow details and wall heat flux …
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A Computational Fluid Dynamics Investigation of Thermoacoustic Instabilities in Premixed Laminar and Turbulent Combustion Systems
… of laminar flat flames and swirl stabilized turbulent flames. A finite-volume based approach is being used to simulate reacting flows in both laminar and turbulent combustors. The study has been divided into three parts -- the first part involves the modeling of a self-excited combustor (the …
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Predicting Soot Emissions with Advanced Turbulent Reacting Flow Modelling
… of size and shape of soot particles in turbulent reacting flows are required, not only for accurate predictions related to flame characteristics but also to meet increasingly stringent regulations. Over the last decades, advances in the understanding of key processes controlling soot …
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Thermoacoustic Effects of a Variable Equivalence Ratio in a Single Element Methane Combustor
<p>Combustion instability is one of the leading factors in limiting the progress and innovations of liquid rocket engines and power plants. Under certain operating conditions, unsteady heat release and acoustic wave interactions can couple and lead to instabilities, such as self-sustaining pressure …
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Modelling of Spray Combustion with Doubly Conditional Moment Closure
Turbulent spray combustion is characterised by a strong coupling of evaporation, mixing and chemical reaction. This leads to a wide spectrum of combustion regimes, where self-propagating premixed flames and diffusion-controlled non-premixed flames may occur simultaneously within the same flame. The …
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Simulations of turbulent swirl combustors
… The first study investigates isothermal air flows behind an enclosed bluff body, with the incoming flow being pulsated. These flows have strong similarities to flows found in combustors experiencing self-excited oscillations and can therefore be considered as canonical problems. At high …