Abstract: Pyrolysis systems and methods of generating hydrogen gas from a hydrocarbon gas. The pyrolysis systems include a solar thermal reactor configured to heat a gaseous hydrocarbon stream, such as methane, to its dissociation temperature. A supersonic turbomachine disposed in a housing receives resulting carbon particles and hydrogen gas from the solar thermal reactor and prevents dissociated carbon from forming deposits on an interior wall of the housing. A particulate separator is located downstream of the supersonic turbomachine to separate the carbon particles from the remaining hydrogen gas.

Abstract: A turbine row for an axial or mixed-flow fluid machine may include an airfoil, having a leading edge, a trailing edge, a pressure surface and a suction surface. The turbine row may further include two endwalls, extending from upstream of the airfoil leading edge to downstream of the airfoil trailing edge. The endwalls may define an inlet upstream of the leading edge of the airfoil and an outlet downstream of the airfoil. The endwalls have a contoured geometry which provides an increase in channel height from the inlet to the outlet and guarantees a throat area larger than the area of the inlet.