1. A method for determining a flow behavior of a medium, comprising: placing at least one analysis device inside the medium, with the at least one analysis device being freely moveable in the medium; supplying data characterizing at least one property of the medium flow behavior from the at least one analysis device to a data evaluation device; determining with the data evaluation device the at least one property of the medium flow behavior, in a flow area through which the at least one analysis device flows with the medium, based on the supplied data characterizing the at least one property of the medium flow behavior.