Experimental and numerical kinetic study on charged and excited species in oxyfuel combustion for CO2 capture
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Within the scope of the work, selected chemical kinetics and combustionissues were investigated.The first part contains a study of high temperature plasma and its po-tential usage as a working fluid in the magnetohydrodynamic generator. Thewell established GRI 3.0 mechanism for methane combustion has been ex-tended to include electrons and ions from literature in order to evaluate theeffect of oxy-fuel combustion on the production of these, hence their potentialto generate a high enough conductivity for MHD applications. The resultsshow, however, that it is highly unlikely to obtain, in the industrial environ-ment, naturally ionized plasma that could be applied as a working fluid inthe effective MHD generator. Electron and ion concentration that defineselectrical conductivity of the fluid is simply not high enough. In other words- without additional seeding that increases electrical conductivity, it wouldbe very problematic (and expensive) for the MHD generator to function withnaturally ionized combustion gasses. The pressure and temperature requiredto obtain naturally ionized plasma characterized by adequate parameters forthe magnetohydrodynamic power plant are beyond the present industrialpossibilities.The second part describes a chemiluminescence study of the excited speciesin various flame types. In this section of the work the previous mechanismhas been further extended to include chemiluminescence reactions for OH*,CH* and CO 2 * from different literature sources. The mechanism has beenvalidated against experiments in both premixed and diffusion flame config-urations. The obtained mechanism can be used to assess the potential formonitoring flames in oxy-fuel conditions. Conducted measurements provesthe accuracy of the created mechanism in case of OH*, CH* and provides agroundwork for the future studies of chemiluminescence phenomena. The second part describes a chemiluminescence study of the excited species in various flame types. Many different variants of combustion mechanisms involving excited species were investigated, resulting in one, consistent set of reactions for chemically excited CH , OH and CO2. Conducted measurements prove the accuracy of the created mechanism and provides a groundwork for the future studies of chemiluminescence phenomena.