Modeling and diagnostics of laser induced plasma for needs of spectrochemical analysis
- Two topics will be addressed: (1) calibration-free LIBS based on Monte Carlo spectral optimization and (2) insight into the possibility of simultaneous elemental and molecular analysis by LIBS. Both topics heavily rely on modeling of laser induced plasma and are closely connected to experiment. In Monte Carlo LIBS (MC LIBS), concentrations are found by fitting model-generated synthetic spectra to experimental spectra. The model of a static uniform isothermal plasma in local thermodynamic equilibrium is employed. Many configurations of plasma parameters and their corresponding spectra are simultaneously generated using a graphic processing unit (GPU). Using the GPU allows for the reduction of computational time down to several minutes for one experimental spectrum that presents the significant progress in comparison with earlier versions of MC LIBS. The method is tested by analyzing industrial oxides containing various concentrations of CaO, Fe2O3, MgO, and TiO2. The agreement withinTwo topics will be addressed: (1) calibration-free LIBS based on Monte Carlo spectral optimization and (2) insight into the possibility of simultaneous elemental and molecular analysis by LIBS. Both topics heavily rely on modeling of laser induced plasma and are closely connected to experiment. In Monte Carlo LIBS (MC LIBS), concentrations are found by fitting model-generated synthetic spectra to experimental spectra. The model of a static uniform isothermal plasma in local thermodynamic equilibrium is employed. Many configurations of plasma parameters and their corresponding spectra are simultaneously generated using a graphic processing unit (GPU). Using the GPU allows for the reduction of computational time down to several minutes for one experimental spectrum that presents the significant progress in comparison with earlier versions of MC LIBS. The method is tested by analyzing industrial oxides containing various concentrations of CaO, Fe2O3, MgO, and TiO2. The agreement within several percent between found and certified concentrations is achieved. Next, a newly developed collisional-dominated model of a laser induced plasma is introduced. The model includes the coupled Navier-Stokes, state, radiative transfer, and material transport equations and incorporates plasma chemistry through the equilibrium approach based on the use of atomic and molecular partition functions. Simple chemical systems are modeled including ablation of Si and C in N2 and Ar atmospheres.The model is used to study evolution of number densities of atomic and molecular species in the expanding plasma plume. The distribution is compared to experimental observations obtained by optical imaging and tomography. To further verify the model, dynamic plasma…
Autor*innen: | Igor B. GornushkinORCiD |
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Koautor*innen: | Sergej V. Shabanov, Reto Glaus, Alexander Demidov, Alexander Ya. Kazakov, Ulrich Panne |
Dokumenttyp: | Vortrag |
Veröffentlichungsform: | Präsentation |
Sprache: | Englisch |
Jahr der Erstveröffentlichung: | 2016 |
DDC-Klassifikation: | Naturwissenschaften und Mathematik / Chemie / Analytische Chemie |
Freie Schlagwörter: | LIBS; Laser induced plasma; Plasma diagnostics; Plasma modeling |
Veranstaltung: | FLAMN 2016 |
Veranstaltungsort: | St. Petersburg, Russia |
Beginndatum der Veranstaltung: | 27.06.2016 |
Enddatum der Veranstaltung: | 01.07.2016 |
Verfügbarkeit des Dokuments: | Datei im Netzwerk der BAM verfügbar ("Closed Access") |
Datum der Freischaltung: | 22.12.2016 |
Referierte Publikation: | Nein |
Eingeladener Vortrag: | Nein |