GB808120A - Improvements in apparatus for effecting heat exchange between two fluid media - Google Patents

Abstract

808,120. Tubular heat exchangers. DALIN, N. A. Sept. 24, 1957 [Oct. 10, 1956], No. 29927/57. Class 64(3) Apparatus for heat exchange between two fluids comprises a helical channel forming a flow path for one fluid, and a plurality of tubes extending along the channel forming a flow path for the other fluid, the two flow paths extending in substantially parallel relationship, each said tube comprising a tube section extending in one direction through the channel connected at one end to a tube section extending in the opposite direction through the channel. In the form shown, the helical channel is formed by a rib 2 mounted on a central core 1 and within a shell 20 at least one end 21 of which is expanded to make a fluid-tight fit with an external casing 3 which is provided with inlet and outlet ports 14, 15 respectively for oil to be heated in flowing through the helical channel. A tube plate 5 is removably secured to one end of the casing 3. Four tubes 9 carrying steam or hot water are coiled helically within the channel each tube forming two passes within the channel and the two passes being joined by a return bend (see Fig. 2) or a return header at the end of the channel remote from the tube plate. The ends of the tubes are received in suitable holes in the tube plate communicating with inlet and outlet headers 10, 11 for the heating fluid. The arrangement is such that all the tubes are of approximately the same length and cross-sectional area so that each tube operates with the same pressure drop. The casing 3 may be omitted. In a modification described two helical channels arranged end to end may be provided within a cylindrical casing having inlets for oil at opposite ends and a central oil outlet, a tube plate being provided at each end of the casing