| 摘要 |
1,220,867. Tubular heat exchangers; steam boilers. VON ROLL A.G. 6 May, 1968 [5 May, 1967], No. 21420/68. Headings F4A and F4S. In a tubular heat-exchange assembly comprising a plurality of identical tubes 3<SP>1</SP> contiguous with a surrounding tubular casing 5 and bounding a central duct 4<SP>1</SP> of varying crosssection, the cross-sectional shape of each tube 3<SP>1</SP> varies along the length of the duct in dependence on its distance S from the duct axis A<SP>1</SP> 4 (see Figs. 2 and 3). The tubes 3<SP>1</SP>, which as shown are in close fitting side-by-side relationship, interconnect annular headers 1 and 2. The heat exchange assembly is mounted on top of a furnace and water is fed through the tubes which act as boiler tubes. The tubes 3<SP>1</SP> can be spaced apart and may be provided on the face bounding the duct 4<SP>1</SP> with studs and a layer of refractory material. An additional set of tubes (R 2 , Fig. 5, not shown), may be coaxially arranged within the casing 5, the circumferential spacing between adjacent such tubes being greater than that between adjacent tubes of the outer set (R 1 ). As an alternative the heating fluid may flow through the tubes and the heat-absorbing fluid through the central duct. |
