GB799486A - Heat exchanger - Google Patents

Abstract

799,486. Heat exchangers. WAAGNERBIRO AKT.-GES. May 23, 1956 [May 26, 1955], No. 15891/56. Class 64(3) A heat exchanger comprises tubular elements 1 for conveying a fluid, juxtaposed to define external spaces 2 for a second fluid flowing in co-current or countercurrent to the first fluid, baffles 8 (Fig. 7) being provided in the elements 1 to effect a swirl in the fluid flowing therethrough. The external fluid may also flow with a swirling motion effected e.g. by baffles 9. Figs. 3, 4 and 8 show alternative crosssectional forms of the elements 1 which are preferably so disposed that the internal and external fluid passages are of substantially equal cross-sectional area. Each element is so shaped in cross-section that slots 4 are formed in the walls whereby the boundary layer of one or both fluids is withdrawn as they pass through the heat exchange zone. In a further form (Fig. 6 not shown) the elements may have ex ternal ribs such that a rectilinear flow is promoted in the external fluid. In Figs. 7 and 8 the heat exchange surface is increased by the provision of other tubular elements 5, 6 arranged as shown, guide vanes 7 being provided around the tubes 5 to further promote heat transfer.