Patent Number: 
Section: claims

1. A reactor configuration, comprising:a reactor core of a boiling water reactor;a separation device for steam/water separation disposed above said reactor core of the boiling water reactor;a flow space formed between the reactor core and said separation device;an internal cross-sectional area; anda flow component disposed in said flow space, said flow component having a central passage defining a flow cross-sectional area, said flow component having an entry side narrowing in a flow direction for initially reducing said flow cross-sectional area and an exit side expanding in said flow direction for increasing said flow cross-sectional area ahead of said separation device;said flow cross-sectional area, directly after said flow component with respect to the flow direction, being substantially defined by said internal cross-sectional area; andsaid separation device including a cyclone device disposed substantially only in a central region of said flow cross-sectional area. 2. The configuration according to claim 1, wherein the narrowing of said entry side is continuous and the expanding of said exit side is abrupt. 3. The configuration according to claim 2, wherein said flow component is a ring element. 4. The configuration according to claim 1, wherein said separation device includes a drying device disposed near said cyclone device. 5. The configuration according to claim 4, further comprising:a steam outlet connection;said cyclone device having an exit side;said drying device formed to exclusively provide a flow path from said exit side of said cyclone device to said steam outlet connection. 6. The configuration according to claim 5, wherein said drying device has a first dryer unit acting on a steam/water mixture emerging from said cyclone device and a second dryer unit acting on a remainder of the steam/water mixture. 7. The configuration according to claim 6, wherein said first dryer unit is disposed between said cyclone device and said second dryer unit. 8. The configuration according to claim 4, wherein said drying device has a first dryer unit acting on a steam/water mixture emerging from said cyclone device and a second dryer unit acting on a remainder of the steam/water mixture. 9. The configuration according to claim 8, wherein said first dryer unit is disposed between said cyclone device and said second dryer unit. 10. The configuration according to claim 1, wherein said separation device includes a drying device disposed in an annular space surrounding said cyclone device.