In many scientific communities, the definition of standardized experiments has enabled major progress in process understanding. The investigation of the spray-flame synthesis of nanoparticles at a well-defined standard burner by experiment and simulation makes it possible to produce a comprehensive data set with various established and novel measuring methods. In this work, we introduce the design of the SpraySyn burner as a new standard for a free-jet type burner that offers well-defined and simulation-friendly boundary conditions and geometries as well as accessibility for optical diagnostics. A combustible precursor solution is fed through a centrally located capillary and aerosolized with an oxygen dispersion gas flow. The spray flame is stabilized by a premixed flat methane/oxygen pilot flame fed via a porous bronze matrix surrounded by a stabilizing nitrogen coflow emanating through the same porous matrix, providing easy-to-calculate boundary conditions for simulations. This burner design enables the use of a wide choice of solvents, precursors, and precursor combinations. Best-practice operating instructions and parameters are given, and large-eddy simulations are performed demonstrating the suitability of the SpraySyn burner for computational fluid dynamics simulations. For ensuring reproducible operation across labs, we define a consumer-camera-based flame characterization scheme for the quantitative assessment of the flame geometry such as flame length, diameter, tilt angle, and photometric distribution of visible chemiluminescence along the center axis. These parameters can be used for benchmarking the pilot and spray flame by each user of the SpraySyn burner with the reference flames.

Although aluminium acetylacetonate, Al(C5H7O2)3, is a common precursor for chemical vapor deposition (CVD) of aluminium oxide, its gas phase decomposition is not very well investigated. Here, we studied its thermal...

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Group additivity methods simplify the determination of thermodynamic properties of a wide range of chemically related species involved in detailed reaction schemes. In this paper, we expand Benson's group additivity method to organosilanes. Based on quantum‐chemical calculations, the thermodynamic data of 22 stable silicon‐organic species are calculated, presented in the form of NASA polynomials, and compared to the available experimental data. Based on this theoretical database, a complete set of 24 Si‐ and C‐atom‐centered, single‐bonded and nonradical group additivity values for enthalpy of formation, standard entropy, and heat capacity at temperatures from 200 to 4000 K is derived through unweighted multivariate linear regression.

The impact of nonideal sorption on atrazine transport was investigated for two sandy porous media with 0.38 and 0.03% organic-carbon contents. In contrast to prior investigations, effluent atrazine concentrations were monitored over a range of five orders of magnitude to examine long-term elution behavior. As characterized by batch experiments, atrazine experienced nonlinear sorption for both media. The results of the column experiments showed that atrazine exhibited extensive elution tailing (delayed approach to relative concentration of zero). This non-ideal transport was more pronounced for the medium with higher organic-carbon content. A mathematical model incorporating nonlinear, rate-limited sorption/desorption described by a continuous distribution function was used to successfully simulate atrazine transport.

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The physical mechanisms responsible for flame curvature evolution of a methane-air premixed flame attached to a bluff-body burner have been investigated using a high-fidelity flame-resolved three-dimensional simulation database. The contributions to the mean curvature generation due to the fluid flow motion and to a combination of flow and flame propagation induced strain rates have been analyzed in detail and dominant contributions in different zones (reactants, flame and products) of the flame have been identified. The effect of fluid flow on the mean curvature evolution is important on the unburned gas side, whereas the flame propagation dominates the mean curvature evolution in the reaction region and towards the hot products. The statistical contributions of the mean curvature transport equation have been analysed in terms of the iso-scalar surface geometry, characterized by the mean and Gauss curvatures. This information has subsequently been used to provide physical insights into the dominant mechanisms of curvature evolution for different flame topologies.