Abstract: In a thermodynamic cycle with at least one first heat exchanger for creating a first heated or partially evaporated working medium flow by heating or partially evaporating a liquid working medium flow by heat transmission from an expanded working medium flow; a second heat exchanger for creating a second at least partially evaporated working medium flow; a separator for separating a liquid from a vaporous phase of the second flow; and an expansion device for creating an expanded vaporous phase, pressure pulsations are prevented during the start-up of the cycle in that the vaporous phase separated by the separator is conducted past the expansion device and the first heat exchanger. The liquid phase separated by the separator is cooled in the first heat exchanger by heat transfer to the liquid flow. After the first heat exchanger, the cooled, separated, liquid phase and the separated vaporous phase are brought together.