Steam generator

A steam generator comprising a vertical casing having a feed-water inlet and an upper portion forming a steam dome having a steam outlet, said casing forming a portion below said dome, having a tube plate forming a closure and a U-tube bundle having upwardly extending hot and cold legs mounted in said tube plate and a primary header below said tube plate and having primary fluid hot and cold nozzles and a partition for directing primary fluid from said hot nozzle through said hot leg and from said cold leg through said cold nozzle, said tube bundle being circumferentially enclosed by a shroud on top of which a group of water separators extends horizontally above at least substantially the horizontal extent of said tube bundle including both of said legs, said separators being under said steam dome, receiving steam-water mixtures rising from both of said legs inside of said shroud, the shroud and the inside of said casing forming a feed-water descent space to which said separators discharge separated water, said casing containing means for diverting part of the steam-water mixture rising from said hot leg to at least a portion of said separators above said cold leg.