Heat exchange – Radiator core type – Deformed sheet forms passages between side-by-side tube means
Patent
1996-01-11
1997-04-29
Flanigan, Allen J.
Heat exchange
Radiator core type
Deformed sheet forms passages between side-by-side tube means
165181, 165183, 165DIG505, F28F 120
Patent
active
056239890
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a finned tube heat exchanger, particularly for the condensation of exhaust streams of large turbine plants by cooling air.
2. Description of the Related Art
The finned tube heat exchanger according to DE-PS 34 19 734 is capable of condensing large quantities of steam. Moreover, it has the advantage that a pressure equalization occurs at any location of the heat exchanger tubes between all areas of the tube cross section. Consequently, the condensation of the exhaust steam ends in the forward tube sections facing the flow direction of the cooling air at exactly the same location as in the tube sections which are at the rear in flow direction of the cooling air. Accordingly, it is not likely that dead zones will be formed. Moreover, relatively large cross sections of the tubes are formed, so that the pressure losses due to the larger hydraulic cross section are significantly reduced.
The fins which project perpendicularly from the surfaces of the heat exchanger tubes are smooth and are constructed without projections.
In contrast to this finned tube heat exchanger, the finned tube heat exchanger according to DE-OS 19 58 909 has stop edges which are integrated in the fins between the heat exchanger tubes. The stop edges are formed by pressing surface portions out of the planes of the fins. Consequently, there are obstacles for the cooling air. The heat transfer is improved as a result of this measure, however, with the disadvantage that the pressure loss is increased by a multiple as a result of the stop edges.
SUMMARY OF THE INVENTION
Starting from the state of the art, the invention is based on the object of perfecting such a finned tube heat exchanger in such a way that the outer heat transfer between the cooling air and the surfaces of the heat exchanger tubes can be substantially increased without significantly increasing the pressure loss.
In accordance with the invention, the fins extend parallel to the flow direction of the cooling air and perpendicularly to the axes of the heat exchanger tubes. The fins have flow conduction devices in the form of air conduction grooves provided on at least one side surface of the fins, wherein the air conduction grooves extend in a zig-zag-shaped configuration parallel next to each other, and wherein the air conduction grooves extend continuously along the flow direction of the cooling air and are open at the fins ends
Consequently, the fins are provided on at least one side surface with air conduction grooves having a zig-zag-shaped configuration. However, in spite of the zig-zag-shaped configuration, the air conduction grooves generally have an oblong extension in the flow direction of the cooling air. They are open at the fin ends and, thus, make it possible for the cooling air to flow in the air conduction grooves, wherein the zig-zag-shaped configuration produces a significantly improved outer heat transfer between the cooling air and the surface of the heat exchanger tubes without significantly increasing the pressure losses.
The air conduction grooves may extend over the entire side surface of a fin. The conduction grooves are preferably produced by embossing both sides of a fin. In that case, the air conduction grooves of adjacent fins are located frontally opposite each other.
The fins configured in accordance with the invention may be provided individually at each heat exchanger tube. However, it is particularly advantageous if two heat exchanger tubes located next to each other are connected to one another in the manner of webs by fins having zig-zag-shaped air conduction grooves. They may be individual fins or wave-shaped or U-shaped or trapezoidally embossed fin strips.
Although it is conceivable that the air conduction grooves are curved in the shape of waves, a preferred embodiment in accordance with claim 2 is seen in that the groove sections of the air conduction grooves which extend at an angle relative to each other are straight. The groove sections are preferably co
REFERENCES:
patent: 2252211 (1941-08-01), Seemiller
patent: 3515207 (1970-06-01), Lu
Flanigan Allen J.
GEA Luftkuhler GmbH
Kueffner Friedrich
LandOfFree
Finned tube 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 Finned tube heat exchanger, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Finned tube heat exchanger will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-700050