ECHANGEUR DE CHALEUR

HEAT EXCHANGER

Abrégé anglais

ABSTRACT OF THE DISCLOSURE
Heat exchangers with heat exchanger elements having a rectangular
or square cross section, of the air/tube dry cooling type, characterized in
that heat exchanger elements are inclined to horizontal at an angle between 15°
and 45° and in that interspaces formed as a result are of V-shaped or inverted
V-shaped cross section and serve to accommodate pipes carrying fluid to be
recooled or to handle and deliver fluid to be recooled directly, said V- or
inverted V-shaped interspaces in the latter case are lined.

Revendications

The embodiments of the invention in which an exclusive property or
privilege is claimed are defined as follows:
1. Heat exchangers with heat exchanger elements having a rectangular
or square cross section, of the air/tube dry cooling type, characterized in that
heat exchanger elements are inclined to horizontal at an angle between 15° and
45° and in that interspaces formed as a result are of V-shaped or inverted
V-shaped cross section and serve to accommodate pipes carrying fluid to be re-
cooled or to handle and deliver fluid to be recooled directly, said V- or inverted
V-shaped interspaces in the latter case are lined.
2. Heat exchangers as in claim 1, in which the V-shaped or inverted
V-shaped interspaces serve exclusively for the direct handling of the fluid to be
recooled, characterized in that the linings of the V-shaped or inverted
V-shaped passages are by convex shaped hoods or hoods with a U-shaped or
inverted U-shaped cross section.

Description

S838
This invention relates to a heat exchanger with heat exchanger
elements having a rectangular or square cross section, typically air/tube dry
cool ing el ements.
It is known to arrange such heat exchanger elements horizontally or
slightly inclined to horizontal. With such an arrangement, the supply, distri-
bution and discharge pipes for the fluid to be recooled, such as water or steam,
reduce the effective face area of the element exposed to the air flow. The
utilization factor (A= effective face area of the element; D = tower diameter at
level of element) in the case of a cooling tower with a circular diameter in known
cooling towers has therefore been not more than 0. 85.
The invention has for its object to provide such an arrangement of
heat exchanger elements and a pipework for the fluid to be recooled which
results in a maximum utilization factor.
According to the invention, this objective is achieved by having the
heat exchanger elements inclined to horizontal by an angle between 15 and 45
and in that the interspaces formed as a result which are of V or inverted V
cross section serve to accommodate the pipework carrying the fluid to be re-
cooled or to handle and deliver the fluid to be recooled directly, the V or
inverted V-shaped interspaces in the latter case being lined. Thanks to the
features according to the invention, it is possible with the indirect method of
cooling to achieve a utilization factor 4 of 0. 95 and more which means that -
with a given cooling tower diameter - a higher transfer performance is obtained
or - with a given heat transfer performance - a cooling tower of a smaller dia-
meter can be adopted. Where the direct method of cooling is adopted, i. e.
where turbine exhaust steam i directly passed into the heat exchanger elements,
i5 is possible with an appropriately large angle of inclination to accommodate
even the steam pipe or duct in the V-shaped interspace without reducing the face
area whereby a more pronounced increase of the utilization factor is obtainable
compared to the indirect method of cooling.
If the V- or inverted V-shaped interspaces are exclusively used for
delivering the fluid to be recooled then, in accordance with a further feature of
the invention, lining of the V or inverted V-shaped passages is by convex shaped
or U-shaped or inverted U-shaped hoods. These features make it possible to
increase the cross section heightwise for the flow passages which may be

necessary especially in the case of the direct cooling method.
A principal object is to provide heat exchangers with heat exchanger
elements having a rectangular or square cross section, of the air/tube dry
cooling type, characterized in that heat exchanger elements are inclined to
horizontal at an angle between 15 and 45 and in that interspaces formed as a
result are of V-shaped or inverted V-shaped cross section and serve to accommo-
date pipes carrying fluid to be recooled or to handle and delivery fluid to be
recooled directly, said V- or inverted V-shaped interspaces in the latter case
are lined.
Two typical embodiments of the invention are shown schematically in
the drawing in which:
Figure 1 shows a part of the heat exchanger elements as an end
view; and
Figure 2 i5 a variant shown in perspective.
The heat exchanger elements 1 are formed with a rectangular cross
section, seen in the plane perpendicular to the pupes 7 and 8 or ducts and may,
for instance, be designed in the manner of the known plate-type heat exchangers
or as "air/tube dry cooling elements~. The term "air/tube dry cooling element~
is defined as denoting an element which has top and bottom surfaces, side sur-
faces and tubes extending transversely to the top and bottom surfaces, such
tubes having cooling air or cooling gas flowing through their inside and the
fluid to be recooled contacting their outside.
The heat exchanger elements 1 - seen in cross section - are rela-
tively deeply inclined to the horizontal 2 by the angle ~ . Each group of two
heat exchanger elements form inverted V-shaped configurations 3a, 3b. The
angle o~ is between 15 and 45 . As a resulf of the inclined arrar,gement of the
heat exchanger elements V-shaped (4a) or inverted V-shaped ~4b3 interspaces
are obtained which are bounded by the side walls 5 of the heat exchanger ele-
ments. The cooling air 6 flows through the elements in the known mannes~ on a
cross-flow pattern.
In the case of the typical embodiment shown in Figure 1, the fluid to
be recooled (e. 9. water or steam~ is supplied to the heat exchanger elemer,ts by
pipes 7. These pipes 7 are arranged in the V-shaped interspaces 4a. The
recooled fluid leaving the heat exchanger elements (cooling water or condensate)

l~I1838
is discharged via pipes 8. The pipes 8 are arranged in the inverted V-shaped
interspace 4b.
In the typical embodiment shown in Figure 2, the V-shaped or
Inverted V-shaped interspaces are lined and the passages bounded by the linings
9 and the side walls 5 are directly used as flow passages for the fluid to be
recooled (e. 9. coolant or steam). The linings may be flat plates or sheets
which connect the corresponding edges of each group of two adjacent heat
exchanger elements.
If higher passages are required, which may be necessary specially in
the case of the direct cooling method where the exhaust steam flows directly
through the heat exchanger elements, then the linings may, for instance, be
convex-shaped hoods, U-shaped hoods or inverted U-shaped hoods which are
not shown specifically.