Gas and liquid contact apparatus – With external supply or removal of heat – Heat exchange means at or downstream of contact zone
Patent
1999-01-14
2000-11-14
Bushey, C. Scott
Gas and liquid contact apparatus
With external supply or removal of heat
Heat exchange means at or downstream of contact zone
261DIG11, 164 60, 264 465, B01F 304
Patent
active
06145818&
DESCRIPTION:
BRIEF SUMMARY
CROSS-REFERENCES TO RELATED APPLICATIONS
This application is a U.S. national application of international application serial No. PCT/DE97/01091 filed May 23, 1997, which claims priority to German Serial No. 196 23 245.7 filed May 30, 1996.
The invention relates to a heat exchanger.
Such heat exchangers are inserted for example in cooling towers. A brine to be cooled is conveyed through a tube register which is sprayed with water from the outside and air flows therethrough in the opposite direction. The heat of this brine is discharged to the outer air by evaporative cooling of the water. In a typical development the tube register comprises stainless steel tubes having a thickness of 15 millimeters. However, since large heat exchange surfaces are required to achieve economic efficiencies the construction of a cooling tower is costly. Although zinc coated steel tubes are used instead of stainless steel tubes, for such a heat exchanger a very high financial effort and substantial space requirement are still present. Hence, generally only closed cooling towers with relatively low efficiencies or despite the risk of contamination, open cooling towers are used wherein the brine is directly sprayed into an airflow.
A heat exchange element incorporable into a conduit having a rectangular cross-section is already known from the DE 32 16 877 C1 which comprises at least one mat body formed of intersecting grid-like flexible plastic tubes so called capillary tubes having a diameter of 2 mm. The mat body represents a wall penetrating through the conduit transversely to its longitudinal direction which may be formed as a heat exchange element comprising several series connected layers of grid-like intersecting tubes by folding about lines being vertically to its axis. The heat exchange element, however, is not sprayed with water.
Hence, it is the object of the present invention to provide a heat exchanger with a tube register through which a fluid to be cooled or heated is conveyed wherein the tube register is sprayed, in the same direction as the field, with water and air flows therethrough in the opposite direction to the fluid. Said heat exchanger can be perferably inserted, for example, into a cooling tower which comprises a high efficiency despite a low cost effort and a compact design.
According to the invention, a heat exchanger includes a tube register through which a fluid to be cooled or heated is conveyed. The tube register is sprayed, in the same direction as the fluid, with water, and air flows therethrough in the opposite direction to the fluid. The tube register include capillary tubes (1) which extend parallel to each other which are folded such that they are bent back, respectively, about one or several lines vertically extending to its longitudinal direction to form layers of the tube register one upon another. The spaces between the capillary tubes (1) at least are partly filled with foamed material (2). In comparison with conventional heat exchangers, the heat exchange surface is multiplied by the capillary tubes which have substantially smaller diameters than the prior art tubes, and by the application of the foamed material. The capillary tubes can be constructed from plastic, and the foamed material can be produced economically.
Suitably, the foamed material comprises mats disposed between adjacent layers of capillary tubes, or the space between the capillary tubes is entirely foamed.
A conventional bare-tube heat exchanger having a constructional depth of 100 cm and tubes, e.g. with an outer diameter of 15 mm comprises a heat exchange surface of 60 m.sup.2 related to m.sup.2 of the air admission surface.
If these tubes are substituted according to the invention by capillary tubes having an outer diameter of 3 mm, for example, this surface already increases to a quintuple, namely to 300 m.sup.2 /m.sup.2 of the air admission surface.
If one respective moulded plate of foamed material having a porosity of 20 ppi (pores per inch) is disposed between two adjacent layers of capillary tubes the foamed
REFERENCES:
patent: 185957 (1877-01-01), Peacock et al.
patent: 3820353 (1974-06-01), Shiraishi et al.
patent: 4177044 (1979-12-01), Jernqvist
patent: 4440698 (1984-04-01), Bloomer
patent: 4461733 (1984-07-01), Otterbein
patent: 4723598 (1988-02-01), Yoshio et al.
patent: 4976113 (1990-12-01), Gershuni et al.
LandOfFree
Heat exchanger does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Heat exchanger, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Heat exchanger will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2056890