GB1410425A - Heat exchangers - Google Patents

Abstract

1410425 Tubular heat exchangers; oncethrough boilers WAAGNER-BIRO AG 7 Feb 1973 [9 Feb 1972] 6104/73 Headings F4S and F4A In a heat exchanger, e.g. a once-through steam boiler for nuclear power stations, comprising a pair of spaced apart tube groups 2 and 3, the region between the units contains baffle or deflector means configured to change the direction of flow of fluid leaving group 2 prior to it entering group 3. As shown the baffle means comprises a plurality of radial plates 4. In use fluid 16 flowing near the centre through tube group 2 is deflected outwardly so that it flows in the outer region through tube group 3. Conversely fluid 15 flowing in the outer region through group 2 is deflected to flow through the central region of group 3. Each of the tube groups 2 and 3 is subdivided into concentrically disposed subgroups 11, 12 and 13, 14, and the tubes comprising the subgroups 11 and 13 may be helical tubes wound in the opposite sense to those in the subgroup 12 and 14 (see Fig. 13). The tube groups 2 and 3 may be interconnected by connecting tubes (5, Fig. 5, not shown) arranged in sector-shaped compartments defined by radially extending deflector plates (4). Additional vane or deflector members (10) may be provided to give the fluid passing through the space 1 a deflection of 180 degrees. In an alternative embodiment (Fig. 6, not shown) the baffle means in the space 1 comprises cylindrical baffle members (4), with the tubes interconnecting the tube groups (2 and 3) being disposed in the bioconcave spaces defined between adjacent cylindrical baffles. Other baffle arrangements (Figs 7-11, not shown) are disclosed; for example the baffles may be in the form of curved plates of helical configuration. Instead of the tube groups being axially spaced from one another, as shown, the second group of tubes (3) may circumferentially surround the first group (see Fig. 12, not shown).