Compact heat exchangers spiral-plate

Figure 13.12 Compact heat exchangers (a) plate-and-frame (b) spiral plate (c) plate fin.

For extended surfaces, which include fins mounted perpendicularly to the tubes or spiral-wound fins, pin fins, plate fins, and so on, friction data for the specific surface involved should be used. For details, see Kays and London (Compact Heat Exchangers, 2d ed., McGraw-HiU, New York, 1964). If specific data are unavailable, the correlation by Gunter and Shaw (Trans. ASME, 67, 643-660 [1945]) may be used as an approximation. 

Types of Heat Exchangers 188 Plate-and-Frame Exchangers 189 Spiral Heat Exchangers 194 Compact (Plate-Fin) Exchangers 194 Air Coolers 194... 

Liquid-to-Liquid Exchangers. Liquid-to-liquid and phase-change exchangers are plate-and-frame and welded PHE, spiral plate, and printed circuit exchangers. Some of these are described in some detail later in this section. Some compact heat exchangers and their applications are now summarized. 

Description These exchangers are typically a series of stacked helical-coiled tubes connected to manifolds, then inserted into a casing or shell. They have many advantages hke spiral-plate designs, such as avoiding differential expansion problems, acceleration effects of the helical flow increasing the heat transfer coefficient, and compactness of plot area. They are typically selected because of their economical design. 

Figure 8.8. Plate and spiral compact exchangers, (a) Plate heat exchanger with corrugated plates, gaskets, frame, and corner portals to control flow paths, (b) Flow patterns in plate exchangers, (i) parallel-counter flows (ii) countercurrent flows (iii) parallel flows throughout, (c) Spiral exchanger, vertical, and horizontal cross sections.

The spiral-plate exchanger is compact 2000 square feet of heat transfer surface can be obtained in a unit 58 inches in diameter with a 72 inch wide plate. 

Packaging of the membrane into a device or module followed the precedents set by past heat exchanger design. Initial desalination devices utilized membrane sheets packaged in a plate and frame device [8]. These devices quickly gave way to more compact hollow fiber and spiral wound module designs. 

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