Multichannel heat exchangers employing flow distribution manifolds
View Patent ↗The present disclosure is directed to heat exchangers with flow distribution manifolds divided into an inlet section and a distribution section by a distributor. The inlet section may have a relatively small cross-sectional area that promotes mixed phase flow of liquid and vapor refrigerant. The manifolds may be used with multichannel tubes with flow path inlet sections that allow refrigerant to enter the flow paths through an outer wall of the tubes. In certain embodiments, a portion of the outer wall is removed to expose the flow paths to a distribution chamber within the inlet manifold. The multichannel tubes extend into the distribution section to partition the distribution section into a series of distribution chambers defined by a pair of adjacent tubes, the distributor, and the inlet manifold. Within each distribution chamber, the refrigerant may be directed into the multichannel tubes through the inlet sections of the multichannel tubes.
1. A heat exchanger, comprising:
a first manifold;
a second manifold;
a distributor disposed within the first manifold to longitudinally divide the first manifold into an inlet section and a tube distribution section; and
a plurality of multichannel tubes extending into the first manifold to form a plurality of distribution chambers within the tube distribution section, each multichannel tube of the plurality of multichannel tubes comprising a first end abutting the distributor in the first manifold, a second end disposed in the second manifold, a top wall, a bottom wall opposite to the top wall, a pair of side walls extending between the top and bottom walls and separated from each other by a plurality of generally parallel flow paths extending between the first and second ends and at least partially occluded by the distributor at the first end, and a flow path inlet section disposed within the inlet section of the first manifold and having a first region with only a portion of the top wall of the respective multichannel tube removed to expose the respective plurality of generally parallel flow paths to a respective chamber of the plurality of distribution chambers and a second region with only a portion of the bottom wall of the respective multichannel tube removed to expose the respective plurality of generally parallel flow paths to a different respective chamber of the plurality of distribution chambers.
2. The heat exchanger of claim 1 , wherein the distributor comprises a plurality of orifices configured to meter a fluid from the inlet section of the first manifold to the tube distribution section of the first manifold.
3. The heat exchanger of claim 2 , wherein each of the plurality of orifices is in fluid communication with a different one of the plurality of distribution chambers.
4. The heat exchanger of claim 1 , wherein the distribution chambers of the plurality of distribution chambers are in fluid communication with one another.
5. The heat exchanger of claim 1 , wherein the inlet section comprises a smaller cross-sectional area than the tube distribution section.
6. The heat exchanger of claim 1 , wherein each distribution chamber of the plurality of distribution chambers is defined by a pair of adjacent multichannel tubes of the plurality of multichannel tubes, the distributor, and the first manifold.
7. The heat exchanger of claim 1 , wherein the first manifold comprises a vertical manifold, and wherein the distributor is configured to force fluid vertically through the manifold within the inlet section.
8. A heat exchanger, comprising:
an inlet manifold;
an outlet manifold;
a distributor disposed within the inlet manifold to longitudinally divide the inlet manifold into an inlet section and a tube distribution section;
a plurality of multichannel tubes, each of the plurality of multichannel tubes comprising:
a top wall;
a bottom wall disposed generally opposite from the top wall;
a pair of side walls extending between the top and bottom walls and separated by a width of the respective multichannel tube;
a plurality of generally parallel flow paths in fluid communication with the inlet manifold and the outlet manifold and extending through the tube distribution section of the inlet manifold to abut the distributor; and
a flow path inlet section comprising:
a first section wherein only a portion of the top wall is removed to expose a first group of the plurality of generally parallel flow paths within the flow path inlet section; and
a second section wherein only a portion of the bottom wall is removed to expose a remaining group of the plurality of generally parallel flow paths within the flow path inlet section; and
a plurality of distribution chambers disposed in the tube distribution section of the inlet manifold, wherein each of the distribution chambers is defined by a different set of two multichannel tubes of the plurality of multichannel tubes, a tube-receiving portion of the inlet manifold, and the distributor.
9. The heat exchanger of claim 8 , wherein the distributor comprises a plurality of orifices configured to meter fluid from the inlet section to the tube distribution section, and wherein each of the plurality of orifices aligns with a different distribution chamber of the plurality of distribution chambers.
10. The heat exchanger of claim 8 , wherein the first section of the flow path inlet section exposes the first portion of the plurality of generally parallel flow paths to one of the plurality of distribution chambers, and the second section of the flow path inlet section exposes the remaining group of the plurality of generally parallel flow paths to a different one of the plurality of distribution chambers.
11. The heat exchanger of claim 10 , wherein each of the plurality of multichannel tubes is configured to receive an external fluid flowing across the width of the respective multichannel tube from a leading edge to a trailing edge, and wherein the second section of the flow path inlet section is adjacent to the leading edge.
12. The heat exchanger of claim 8 , wherein the inlet manifold comprises a tubular structure with opposite ends enclosed by end caps, and wherein the distributor abuts each of the end caps.