Abstract: An internal combustion engine with combined pressure charging has an exhaust turbocharger turbine arranged in an exhaust conduit of the internal combustion engine driving a compressor arranged in an intake conduit. A mechanically driven supercharger is arranged downstream of the compressor and is coupled continuously variably to the engine via a Fottinger speed transformer with variable-pitch guide vanes and variable speed slip. To bypass the mechanically driven supercharger, a bypass conduit is provided. A circulating-air slide is arranged in the bypass conduit for controlling the air quantity bypassing the mechanically driven supercharger. The degree of opening of the circulating-air slide and the slip of the Fottinger speed transformer are controlled as a function of operating parameters such that the charge-air pressure is adjusted to a predetermined set point value.

Abstract: A regenerative heat-exchanger of a gas turbine whose ceramic heat-exchanger disk is coaxially surrounded by a metallic toothed rim under formation of an annular space in which are arranged springs; the springs are constituted by spring packets of cup springs which are guided on both sides in concave recesses in two webs arranged in the circumferential direction on entrainment plates which surround the lateral surfaces of the toothed rim and are non-rotatably connected therewith.