Circular cross flow in steam generator

Claim 1

A STREAM GENERATOR COMPRISING AN OUTER CONTAINMENT SHELL HAVING A VERTICALLY ELONGATED CYLINDRICAL SIDE WALL, A TOP HEAD AND A BOTTOM HEAD, A VESSEL DEFINING AN ELONGATED VERTICALLY DISPOSED CHAMBER OF ANNULAR CROSSSECTION CLOSED AT OPPOSITE ENDS CONCENTRICALLY POSITIONED WITHIN THE SPACE DEFINED BY SAID CYLINDRICAL SIDE WALL OF SAID SHELL, SAID ANNULAR CHAMBER BEING OF A REDUCED DIAMETER AS COMPARED TO SAID CYLINDRICAL SIDE WALL AND FORMING THEREBETWEEN AN ANNULAR VERTICALLY ELONGATED PASSAGEWAY, A VERTICALLY ELONGATED GAS-IMPERVIOUS BAFFLE PLATE WITHIN SAID VESSEL EXTENDING TRANSVERSELY ACROSS SAID ANNULAR CHAMBER, A VERTICALLY ELONGATED PERFORATED BAFFLE PLATE ADJACENT ONE SIDE OF SAID GAS-IMPERVIOUS BAFFLE PLATE, CIRCUMFERENTIALLY SPACED THEREFROM AND FORMING THEREWITH AN INLET PASSAGEWAY WITHIN SAID CHAMBER ON ONE SIDE OF SAID GAS-IMPERVIOUS BAFFLE ADAPTED TO BE CONNECTED TO A SOURCE OF PRE-HEATED GAS THROUGH THE LOWER END OF SAID CHAMBER, SAID PERFORATED BAFFLE PLATE DEFINING A PLURALITY OF VERTICALLY SPACED ORIFICES PROVIDING COMMUNICATION BETWEEN SAID INLET PASSAGEWAY AND SAID ANNULAR CHAMBER, MEANS DEFINING AN OUTLET OPENING IN THE UPPER END OF SAID CHAMBER ADJACENT THE OPPOSITE SIDE OF SAID IMPERVIOUS BAFFLE THROUGH WHICH THE GAS MAY BE DISCHARGED FROM SAID CHAMBER INTO THE SPACE DEFINED BY SAID TOP HEAD, THE RELATIVE POSITIONS OF SAID INLET PASSAGEWAY AND SAID OUTLET CAUSING THE GAS TO TRAVEL IN A GENERAL CIRCULAR PATH THROUGH SAID CHAMBER FROM SAID INLET ORIFICES TO SAID OUTLET OPENING, SAID ANNULAR CHAMBER DEFINING VESSEL ADDITIONAL DEFINING A CYLINDRICAL PASSAGEWAY CONCENTRIC WITH SAID CHAMBER AND INTERIORLY LOCATED WITH RESPECT THERETO COMMUNI-