Refrigerant heat exchanger with integral multipass and flow distribution technology

A microtube heat exchanger for cooling or heating refrigerant fluid of a heat exchange system, the microtube heat exchanger comprising:

• a tube stack comprising a plurality of microtubes aligned substantially parallel to each other to form the tube stack, wherein refrigerant fluid is configured to pass though the plurality of microtubes so that heat can be transferred between the refrigerant fluid and an external fluid flowing past an exterior of the plurality of microtubes;
• a first header disposed on a first end of the tube stack and comprising an inlet port coupled with a refrigerant fluid inlet of the heat exchanger and through which refrigerant fluid traveling in a first direction is introduced into the tube stack;
• and
• a second header disposed at a second end of the tube stack and comprising a second header passage configured to receive refrigerant fluid traveling in the first direction through some of the plurality of microtubes and discharge the received refrigerant fluid in a second direction to some of the plurality of microtubes,
• wherein the first header further comprises a first header passage configured to receive refrigerant fluid traveling in the second direction through some of the plurality of microtubes and discharge the received refrigerant fluid in the first direction to some of the plurality of microtubes, and
• wherein the second header further comprises an outlet port configured to receive refrigerant fluid traveling through some of the plurality of microtubes in the first direction and discharge the received refrigerant fluid to a refrigerant fluid outlet of the heat exchanger;
• wherein first header passage and the second header passage each comprise a surface segregated into a plurality of separate surface portions by a groove projecting outward from the surface, the separate surface portions each being co-planar with each other, and each of the separate surface portions being an inlet surface including an inlet port or an outlet surface including an outlet port.

A microtube heat exchanger for cooling or heating refrigerant fluid of a heat exchange system, the microtube heat exchanger comprising:

• a tube stack comprising a plurality of microtubes aligned substantially parallel to each other to form the tube stack, wherein refrigerant fluid is configured to pass though the plurality of microtubes so that heat can be transferred between the refrigerant fluid and an external fluid flowing past an exterior of the plurality of microtubes;
• a first header disposed on a first end of the tube stack and comprising an inlet port coupled with a refrigerant fluid inlet of the heat exchanger and through which refrigerant fluid traveling in a first direction is introduced into the tube stack;
• and
• a second header disposed at a second end of the tube stack and comprising a second header passage configured to receive refrigerant fluid traveling in the first direction through some of the plurality of microtubes and discharge the received refrigerant fluid in a second direction to some of the plurality of microtubes,
• wherein the first header further comprises a first header passage configured to receive refrigerant fluid traveling in the second direction through some of the plurality of microtubes and discharge the received refrigerant fluid in the first direction to some of the plurality of microtubes, and
• wherein the second header further comprises an outlet port configured to receive refrigerant fluid traveling through some of the plurality of microtubes in the first direction and discharge the received refrigerant fluid to a refrigerant fluid outlet of the heat exchanger;
• wherein each of the first header passage and the second header passage each comprise:
• an inlet surface including an inlet port configured to receive the refrigerant fluid from the tube stack;
• an outlet surface including an outlet port configured to discharge the received fluid toward the tube stack;
• and
• a channel fluidly coupling the inlet port and the outlet port;
• wherein the first header passage and the second header passage each further comprise a curved inlet surface transitioning between the inlet surface and the inlet port, and a curved outlet surface transitioning between the outlet surface and the outlet port.