Heat exchanger and air-conditioning apparatus employing the same

Patent metadata

Field	Value
Publication number	US-2023168047-A1
Application number	US-202017921188-A
Country	US
Kind code	A1
Filing date	Jun 8, 2020
Priority date	Jun 8, 2020
Publication date	Jun 1, 2023
Grant date	—

Abstract

A heat exchanger includes a plurality of flat tubes, and a header. A flow passage provided inside the header includes a plurality of partition portions each provided between the adjacent flat tubes, a plurality of insertion portions formed between the adjacent partition portions, a first communication passage allowing one ends of the adjacent insertion portions to communicate with each other, and a second communication passage allowing an other ends of the adjacent insertion portions to communicate with each other. A cross-sectional area of the first communication passage is larger than a cross-sectional area of the second communication passage, and the first communication passage is provided with a first refrigerant inlet connected to the flow passage and allowing the refrigerant to flow into the header. Thus, a heat exchanger performance can be improved by reducing a refrigerant pressure loss and by achieving uniform distribution of the refrigerant.

First claim

1 . A heat exchanger comprising:
a plurality of flat tubes extending in a first direction and arranged with spacing from each other in a second direction perpendicular to the first direction, a cross-section of each of the plurality of flat tubes in the second direction being an elongated shape; and a header extending in the second direction and connecting to end portions of the adjacent flat tubes of the plurality of flat tubes in the first direction, the header being having inside a flow passage through which refrigerant flows, the flow passage including a plurality of partition portions each provided between the adjacent flat tubes and configured to block at least a part of the flow passage between the adjacent flat tubes to prevent the refrigerant from flowing in the second direction, a plurality of insertion portions formed between the adjacent partition portions, each of the plurality of insertion portions forming a space where the refrigerant flows in a third direction perpendicular to the first direction and the second direction, each of the plurality of flat tubes being inserted in to each of the plurality of insertion portions, a first communication passage allowing one ends of the adjacent insertion portions in the third direction to communicate with each other, and a second communication passage allowing an other ends of the adjacent insertion portions in the third direction to communicate with each other, a cross-sectional area of the first communication passage, of a cross-section perpendicular to the second direction, being larger than a cross-sectional area of the second communication passage, of a cross-section perpendicular to the second direction, the first communication passage being provided with a first refrigerant inlet connected to the flow passage and allowing the refrigerant to flow into the header.

2 . The heat exchanger of claim 1 , wherein a width of at least a connection portion of the insertion portion connected to the second communication passage in the second direction is smaller than a width of the partition portion in the second direction.

3 . The heat exchanger of claim 1 , wherein
the plurality of flat tubes are arranged to extend in an up and down direction, and the header is provided at at least one of end portions of the plurality of flat tubes in an upper side and a lower side in the first direction.

4 . The heat exchanger of claim 1 , wherein,
where a passage cross-sectional area of the first communication passage in the first direction is S 1 and a passage cross-sectional area of the second communication passage in the first direction is S 2 , a quotient obtained by dividing S 2 by Si is greater than 0.15 and less than 0.8.

5 . The heat exchanger of claim 1 , wherein the plurality of flat tubes are inserted into the header with protruding only in the second communication passage when viewed in the first direction.

6 . The heat exchanger of claim 1 , wherein the header includes a contraction hole in a connection portion between the first communication passage and the plurality of insertion portions, the contraction hole being provided only in the first communication passage.

7 . The heat exchanger of claim 1 , wherein the header includes a connection passage connecting the first communication passage and the second communication passage, the connection passage being provided at at least one of the plurality of partition portions.

8 . The heat exchanger of claim 1 , wherein a part of the first communication passage or a part of the second communication passage of the header is blocked from the insertion portions.

9 . The heat exchanger of claim 1 , further comprising another heat exchanger provided at an upstream side in a flow direction of the refrigerant,
wherein, the header is connected, through the first communication passage, to a header of the another heat exchanger at which flow passages of a plurality of flat tubes are merged, wherein, where a passage having a larger passage cross-sectional area in the first direction is the first communication passage, and a passage having a smaller passage cross-sectional area in the first direction is the second communication passage, a passage diameter of a second refrigerant inlet connecting the header of the another heat exchanger with the second communication passage is smaller than a passage diameter of the first refrigerant inlet connecting the header of the another heat exchanger with the first communication passage, or the second refrigerant inlet does not connect to the header.

10 . The heat exchanger of claim 9 , wherein, in the header, at least one of the plurality of the flat tubes provided at the upstream side in the flow direction of the refrigerant functions as the second refrigerant inlet.

11 . An air-conditioning apparatus comprising a heat pump type refrigerant circuit which includes at least a compressor, a condenser, an expansion valve and an evaporator,
wherein the condenser or the evaporator is the heat exchanger of claim 1 .

12 . The air-conditioning apparatus of claim 11 , wherein the refrigerant is R32 refrigerant containing at least an olefin-based refrigerant, propane, DME (dimethyl ether), or a refrigerant having a lower gas density than that of R410A refrigerant.

Assignees

• Mitsubishi Electric Corp

Inventors

• Miyawaki Kosuke
• Onaka Yoji

Classifications

• F28F1/02

  Tubular elements of cross-section which is non-circular (F28F1/08, F28F1/10 take precedence) · CPC title

• F28F9/0221

  Header boxes or end plates formed by stacked elements · CPC title

• F28F9/0224

  Header boxes formed by sealing end plates into covers (F28F9/0221 takes precedence) · CPC title

• F28F9/026

  with static flow control means, e.g. with means for uniformly distributing heat exchange media into conduits · CPC title

• F28D1/05383

  with multiple rows of conduits or with multi-channel conduits (F28D1/05391 takes precedence) · CPC title