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Biogas, landfill gas, associated petroleum gas, and other tail gases accompanying various industrial processes are potential sources of hydrogen and carbon monoxide for solid oxide fuel cells via the reforming process. As these gases contain heavy hydrocarbons, fine-tuning of steam and carbon dioxide addition and specific temperature control are necessary to avoid carbon deposition during the reforming process. Numerical simulation plays a crucial role in designing miniaturized steam reforming reactors and optimal working conditions. All simulations of reforming processes must account for carbon deposition. The methods commonly seen in the open literature include Gibbs free energy minimization or parametric equations formalism. This paper utilizes Gaussian process regression as a tool for making predictions about which reforming parameters are suitable for carrying out this process without the danger of damaging the catalyst due to a carbon formation. Parametric equations formalism and Gibbs free energy minimization involve either the minimization of objective function or a search for roots of nonlinear functions. These tasks are sensitive to a choice of the starting points of the algorithm — wrong choice of starting points could lead to numerical instability. Unlike conventional methods, the Gaussian process regression approach bypasses the computation of equilibrium composition. It predicts carbon formation tendencies directly from the initial conditions which ensure stability.

The technology of solar-powered aerial vehicles requires enormous financial support and further development. For this purpose, the computational fluid dynamic can be used. In order to carry out necessary analyses and model development in this research, ANSYS Fluent software was used. Using the first version of the AGH Solar Plane model, preliminary analysis of lift, drag and tearing off the stream were performed. Numerical experiments made it possible to verify many various profiles and final selection that the best suits the target model. Through these studies, it was also possible to analyse fluid flow at various speeds and angles of attack. This provided an insight into important aspects of vehiclesaerodynamic design, which should be taken into account when making the second model version. At this stage, the classical and laminar - Wortmann aerodynamic profiles were selected on the basis of the aerodynamic perfection criterion. Moreover, four new geometries were prepared on which the flattening of upper surfaces (for fixing solar panels) was tested. The results of the numerical analysis were validated in the aerodynamic tunnel using particle image velocimetry method. Taking into account all analyses, a number of recommendations have been prepared that will be implemented in order to create an aircraft, which meets all target requirements. Some of these hints were: testing new ways of connecting the wing to the nacelle, which would reduce the drag as well as considering the usage of winglets in order to minimize induced drag.