US 2003/0141044 A1 · Parallel slot heat exchanger

Abstract

A heat exchanger in which a fluid and a surface transfer thermal energy effectively with a smaller pressure drop than is conventionally realized. In a preferred embodiment, gas at one end of a piston flows into a piston chamber and passes radially through a plurality of axial slots formed through the piston sidewall and into a gap between the piston sidewall and the surface of the housing in which the piston slidably mounts. Between each pair of through-slots, longer axial slots are formed that extend only partially through the sidewall radially, and almost the entire length of the piston. Thus, around the circumference of the piston the slots alternate in structure between through-slots and longer slots. Gas that enters the gap through the through-slots flows circumferentially through the gap and into the longer slots. The gas exits the longer slots at the opposite end of the piston from the first gas space.

Claims44

Dependent claims

A heat exchanger apparatus for transferring thermal energy between a fluid and a first wall surface, the apparatus comprising:

(a) a second wall having a wall surface spaced from and facing the first wall surface forming a gap between the first wall surface and the second wall surface;
(b) a first elongated slot formed in the second wall surface, the first slot opening into the gap and being in direct fluid communication with a fluid source;
and
(c) a second elongated slot formed in the second wall surface and spaced laterally from the first elongated slot, the second slot opening into the gap and being in direct fluid communication with a fluid destination.

1 more element

A heat exchanger apparatus for transferring thermal energy between a gas and a housing, the housing having a circular cylindrical surface in which a piston is slidably mounted, the piston having a hollow cylindrical sidewall and first and second endwalls mounted to opposite ends of the sidewall defining a piston chamber within the piston sidewall and endwalls, said first and second endwalls defining first and second gas spaces, respectively, on opposite ends of the piston, and an annular gap formed between the housing surface and the sidewall, the heat exchanger apparatus comprising:

(a) at least one gas passageway formed through the first endwall forming a gas flow passage between the first gas space and the piston chamber;
(b) a first slot formed in a radially outwardly facing surface of the sidewall, said first slot having an axial component and a depth equal to a piston sidewall thickness forming a gas flow path between the piston chamber and the annular gap, the first slot extending along the piston sidewall from near the first endwall to near the second endwall;
(c) a second slot formed in the radially outwardly facing surface of the sidewall spaced from the first slot and substantially parallel thereto, the second slot having an axial component and a depth less than the piston sidewall thickness, the second slot extending along the piston sidewall from near the first endwall to and through the second endwall forming a gas flow path between the annular gap and the second gas space;
(d) a third slot formed in the radially outwardly facing surface of the sidewall spaced from the second slot and substantially parallel thereto, said third slot having an axial component and a depth equal to the piston sidewall thickness forming a gas flow path between the piston chamber and the annular gap, the third slot extending along the piston sidewall from near the first endwall to near the second endwall;
and
(e) a fourth slot formed in the radially outwardly facing surface of the sidewall spaced from the first and third slots and substantially parallel thereto, the fourth slot having an axial component and a depth less than the piston sidewall thickness, the fourth slot extending along the piston sidewall from near the first endwall to and through the second endwall forming a gas flow path between the annular gap and the second gas space.

3 more elements

A heat exchanger apparatus for transferring thermal energy between a fluid and a housing, the housing having a radially outwardly facing circular cylindrical surface and a collar mounted to the housing, the collar having a radially inwardly facing circular cylindrical surface spaced radially from the cylindrical surface of the housing defining an annular gap therebetween, the apparatus comprising:

(a) a first elongated slot formed in the inwardly facing surface of the collar and opening into the gap;
(b) a second elongated slot formed in the inwardly facing surface of the collar and spaced from and substantially parallel to the first elongated slot, the second slot opening into the gap;
(c) a third elongated slot formed in the inwardly facing surface of the collar and spaced from and substantially parallel to the second elongated slot, the third slot opening into the gap;
(d) a fourth elongated slot formed in the inwardly facing surface of the collar and spaced from and substantially parallel to the third elongated slot, the fourth slot opening into the gap
(e) a first circumferential, annular groove formed around the collar in a surface of the collar opposite the slots, the first groove having at least one fluid aperture extending through the collar into the first and third slots;
and
(f) a second circumferential, annular groove formed around the collar in the surface of the collar opposite the slots, and spaced from the first circumferential, annular groove a distance substantially equal to the length of the slots, the second groove having at least one fluid aperture extending through the collar into the second and fourth slots.

4 more elements

Dependencies are inferred from the claim text.

Parallel slot heat exchanger

Life of this patent

Parallel slot heat exchanger

Life of this patent

Abstract

Claims44