Single crystals and polycrystalline diamond films of several thicknesses were deposited using oxygen/acetylene combustion flame technique. The substrate used was pure polycrystalline molybdenum subjected to mechanical polishing. Quality and microstructural characteristic of diamond produced were investigated using X-Ray diffraction, Raman Spectroscopy, Scanning and Transmission Electron Microsc...

Multiple flame-flame interactions in premixed combustion are investigated using Direct Numerical Simulations of twin turbulent V-flames for a range of turbulence intensities and length scales. Interactions are identified using a novel Automatic Feature Extraction (AFE) technique, based on data registration using the Dual-Tree Complex Wavelet Transform. Information on the time, position and type...

Infrared images provide useful information to inspect the status of combustion processes. The flame geometry and intensity depend on the process variables and the characteristics of the combustion chamber. This paper describes methods to analyze infrared images of industrial flames and to characterize the flame geometry. A segmentation algorithm is proposed to separate the flame region from the...

The latest techniques used to prove, describe and analyze the gas phase activity of a fire retardant used in polymeric materials are briefly reviewed. Classical techniques, such as thermogravimetric analysis or microscale combustion calorimetry, as well as complex and advanced analytical techniques, such as modified microscale combustion calorimeter (MCC), molecular beam mass spectroscopy and v...

This paper proposes an end-to-end convolutional selective autoencoder approach for early detection of combustion instabilities using rapidly arriving flame image frames. The instabilities arising in combustion processes cause significant deterioration and safety issues in various human-engineered systems such as land and air based gas turbine engines. These properties are described as self-sust...

Laminar hydrocarbon flames, which have adiabatic flame speeds on the order of a meter per second, are conventionally described by a leading convective-diffusive zone followed by an energyreleasing reactive-diffusive region. On the other hand, combustion induced by a strong shock wave is typically modeled as a convective-reactive balance with negligible diffusion, which may be called a convectiv...

Direct numerical simulation (DNS) results of turbulent MILD premixed and conventional (undiluted) premixed combustion have been investigated to shed light on the physical aspects of reaction zones and their morphology in MILD combustion. Results of a premixed case are used for comparative analyses. The analyses show that the regions with strong chemical activity in MILD combustion are distribut...

Microgravity combustion is fundamentally characterized by the absence of buoyancy driven flows. To facilitate a large range of diagnostics on microgravity flames, it is useful to create an equivalent microbuoyant condition in an earth-based laboratory. This experiment simulates microbuoyancy using electric fields to balance local convection in a region of the flame. Previous studies used N2 coh...

The objective of this work was to investigate the influence of preferential diffusion on flame structure and propagation of lean-premixed hydrogen-carbon monoxide syngas-air flame at elevated pressure using direct numerical simulation (DNS) and detailed chemistry. The physical problem investigated is lean-premixed H2/CO outwardly propagating turbulent spherical flame at constant pressure of 4ba...

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