FINNED TUBE WITH INDENTATIONS
A tube used for heat transfer has adjacent fins extending from an outer surface of the tube with a channel between the fins. The fins include a roof formed over the channel, and holes penetrate the roof into the channel. The fin, including the roof, is monolithic with the tube body. Helical ridges are formed on a tube inner surface, and the tube body includes an indentation in the outer surface which extends the tube body inner surface towards a tube axis.
1 . A finned tube comprising:
a tube body having an outer surface, an inner surface, and an axis;
at least one monolithic fin defined on the tube body outer surface such that, in the axial direction, the tube outer surface has adjacent fins, wherein a channel is defined between adjacent fins, and wherein the fin has an upper portion deformed to form a roof over the channel, and wherein the roof defines holes penetrating in to the channel;
a plurality of helical ridges defined on the tube body inner surface;
at least one helical indentation defined in the tube body outer surface such that the indentation extends the tube body inner surface towards the tube axis.
2 . A finned tube comprising:
a tube body having an inner surface;
a helical ridge defined on the tube body inner surface; and
an indentation defined in the tube body, the indentation looping around the tube.
3 . The finned tube of claim 2 wherein the indentation is helical, and wherein the indentation spirals around the tube in the opposite direction of the ridge.
4 . The finned tube of claim 2 wherein the indentation is helical, and wherein the indentation spirals around the tube in the same direction as the ridge.
5 . The finned tube of claim 2 wherein the indentation further comprises a plurality of indentations forming successive rings around the tube.
6 . The finned tube of claim 2 wherein the indentation further comprises a plurality of helical indentations spiraling around the tube body in opposite directions.
7 . The finned tube of claim 2 wherein the tube body includes an outer surface, the finned tube further comprising a monolithic helical fin defined on the tube body outer surface such that the tube body outer surface includes adjacent fins when viewed axially, wherein a channel is defined between adjacent fins, and wherein the fin includes an upper portion deformed to form a roof over the channel.
8 . The finned tube of claim 7 wherein the tube body outer surface, adjacent fins, and the roof define a boiling cavity, and wherein the roof defines a plurality of roof holes penetrating into the boiling cavity.
9 . The finned tube of claim 8 wherein the fins include a fin top having notches, and the notches define the roof holes.
10 . The finned tube of claim 2 wherein the tube is comprised of copper.
11 . A finned tube comprising:
a tube body having an outer surface;
a monolithic fin defined on the outer surface such that the outer surface includes adjacent fins viewed in the axial direction, wherein a channel is defined between adjacent fins, and wherein the fins include an upper portion deformed into a roof over the channel; and
an indentation defined in the tube body, the indentation looping around the tube.
12 . The finned tube of claim 11 wherein the indentation is helical.
13 . The finned tube of claim 11 wherein the indentation further comprises a plurality of helical indentations spiraling around the tube in opposite directions.
14 . The finned tube of claim 11 wherein the indentation further comprises a plurality of indentations forming successive rings around the tube body.
15 . The finned tube of claim 11 wherein the tube body further includes an inner surface, the finned tube further comprising a helical ridge defined on the tube body inner surface.
16 . The finned tube of claim 15 wherein the indentation is helical and the indentation spirals around the tube in the opposite direction as the ridge.
17 . The finned tube of claim 15 wherein the indentation is helical and the indentation spirals around the tube in the same direction as the ridge.
18 . The finned tube of claim 15 wherein the tube body outer surface, adjacent fins, and the roof define a boiling cavity, and the roof defines a plurality of holes penetrating into the boiling cavity.
19 . The finned tube of claim 18 wherein the indentation interrupts the boiling cavity.
20 . The finned tube of claim 11 wherein the tube is comprised of copper.