Fabricated heat exchange tube for microchannel heat exchanger

Abstract

A heat exchange tube segment for use in a heat exchange includes a fabricated tube body having an upper surface, a lower surface, a leading edge, a trailing edge, and a plurality of fluidly distinct flow channels formed therein. The fabricated tube body has a length, width, height, and a total tube cross-sectional area measured between the upper surface, the lower surface, the leading edge, and the trailing edge. A ratio of the width to the height of the fabricated tube body is between about 10 and 20 and a ratio of the width to a number of the plurality of fluidly distinct flow channels is between 1 and 2.5. Each of the plurality of fluidly distinct flow channels forms an open area in a cross-section of the fabricated tube body, and a ratio of the open area to the total tube cross-sectional area is between 0.3 and 0.44.

What is claimed is: 
     
         1 . A heat exchange tube segment for use in a heat exchanger, the heat exchange tube segment comprising:
 a fabricated tube body having an upper surface, a lower surface, a leading edge, a trailing edge, and a plurality of fluidly distinct flow channels formed therein;   wherein the fabricated tube body has a length measured parallel to the plurality of fluidly distinct flow channels, a width measured between the leading edge and the trailing edge, a height measured between the upper surface and the lower surface, and a total tube cross-sectional area measured between the upper surface, the lower surface, the leading edge, and the trailing edge;   wherein a ratio of the width to the height of the fabricated tube body is between about 10 and 20, a ratio of the width to a number of the plurality of fluidly distinct flow channels is between 1 and 2.5; and   wherein each of the plurality of fluidly distinct flow channels forms an open area in a cross-section of the fabricated tube body, and a ratio of the open area to the total tube cross-sectional area is between 0.30 and 0.44.   
     
     
         2 . The heat exchange tube segment of  claim 1 , wherein the ratio of the width to the number of the plurality of fluidly distinct flow channels is between 1.3 and 2.5. 
     
     
         3 . The heat exchange tube segment of  claim 1 , wherein the ratio of the open area to the total tube cross-sectional area is between 0.36 and 0.40. 
     
     
         4 . The heat exchange tube segment of  claim 1 , wherein the plurality of fluidly distinct flow channels are configured to receive a refrigerant, the refrigerant is selected from methylene fluoride and difluoromethylene. 
     
     
         5 . The heat exchange tube segment of  claim 1 , wherein the fabricated tube body comprises a single piece of material folded to form the upper surface, the lower surface, the leading edge, the trailing edge, and the plurality of fluidly distinct flow channels. 
     
     
         6 . A heat exchanger comprising:
 a first manifold;   a second manifold;   a plurality of heat exchange tube segments extending between and fluidly coupling the first manifold and the second manifold, wherein at least one the plurality of heat exchange tube segments further comprises:   a fabricated tube body having an upper surface, a lower surface, a leading edge, a trailing edge, and a plurality of fluidly distinct flow channels formed therein;   wherein the fabricated tube body has a length measured parallel to the plurality of fluidly distinct flow channels, a width measured between the leading edge and the trailing edge, a height measured between the upper surface and the lower surface, and a total tube cross-sectional area measured between the upper surface, the lower surface, the leading edge, and the trailing edge;   wherein a ratio of the width to the height of the fabricated tube body is between about 10 and 20, and a ratio of the width to a number of the plurality of fluidly distinct flow channels is between 1 and 2.5; and   wherein each of the plurality of fluidly distinct flow channels forms an open area in a cross-section of the fabricated tube body, and a ratio of the open area to the total tube cross-sectional area is between 0.30 and 0.44.   
     
     
         7 . The heat exchanger of  claim 6 , wherein the heat exchanger has a multi-pass configuration. 
     
     
         8 . The heat exchanger of  claim 7 , wherein the heat exchanger has a first pass and a second pass, and a number of heat exchange tube segments associated with the first pass is greater than a number of heat exchange tube segments associated with the second pass. 
     
     
         9 . The heat exchanger of  claim 8 , wherein a ratio of the number of heat exchange tube segments associated with the first pass to the number of heat exchange tube segments associated with the second pass is between 1 and 3. 
     
     
         10 . The heat exchanger of  claim 8 , wherein a ratio of the number of heat exchange tube segments associated with the first pass to the number of heat exchange tube segments associated with the second pass is between 1.2 and 3. 
     
     
         11 . The heat exchanger of  claim 6 , wherein the ratio of the width to the number of the plurality of fluidly distinct flow channels is between 1.3 and 2.5. 
     
     
         12 . The heat exchanger of  claim 6 , wherein the ratio of the open area to the total tube cross-sectional area is between 0.36 and 0.40. 
     
     
         13 . The heat exchanger of  claim 6 , wherein the plurality of fluidly distinct flow channels are configured to receive a refrigerant, the refrigerant being one of methylene fluoride and difluoromethylene. 
     
     
         14 . The heat exchanger of  claim 6 , wherein the fabricated tube body comprises a single piece of material folded to form the upper surface, the lower surface, the leading edge, the trailing edge, and the plurality of fluidly distinct flow channels. 
     
     
         15 . The heat exchanger of  claim 6 , wherein the heat exchanger is a condenser in a chiller.