Tube with conductive fins

Abstract

A tube includes a center tube comprising a steel material, a fluid flowing through the center tube; and at least one disk disposed around the center tube, the disk including a thermally conductive material and exposed to an external heat source. The disk conducts heat from the external heat source into the center tube. The center tube transfers the heat from the external heat source into the fluid. The thermal conductivity of the at least one disk is higher than the thermal conductivity of the center tube.

What is claimed is: 
     
         1 . A tube comprising:
 a center tube comprising a steel material, a fluid flowing through the center tube; and   at least one disk disposed around the center tube, the at least one disk comprising a thermally conductive material, the at least one disk exposed to an external heat source,   wherein the at least one disk conducts heat from the external heat source into the center tube;   wherein the center tube transfers the heat from the external heat source into the fluid, and   wherein a thermal conductivity of the at least one disk is higher than a thermal conductivity of the center tube.   
     
     
         2 . The tube of  claim 1 , further comprising at least one fin segment disposed in the at least one disk. 
     
     
         3 . The tube of  claim 1 , wherein the at least one disk is bonded to the center tube via a high-frequency welding process. 
     
     
         4 . The tube of  claim 1 , wherein the at least one disk further comprises a continuous ring-shaped disk. 
     
     
         5 . The tube of  claim 1 , wherein the at least one disk is at least partially composed of at least one of aluminum, beryllium, copper, gold, magnesium, iridium, molybdenum, rhodium, silver, and tungsten. 
     
     
         6 . The tube of  claim 1 , wherein the center tube is at least partially composed of at least one of carbon steel, alloy steel, stainless steel, ferritic stainless, and austenitic stainless. 
     
     
         7 . The tube of  claim 1 , further comprising multiple disks, wherein the tube comprises between about 80 and about 450 disks per meter of tube length. 
     
     
         8 . The tube of  claim 7 , wherein at least one disk of the multiple disks is longitudinally aligned with at least one adjacent disk. 
     
     
         9 . The tube of  claim 7 , wherein the at least one disk wraps around the center tube in a spiral configuration. 
     
     
         10 . The tube of  claim 1 , wherein the at least one disk comprises a thickness between about 0.5 mm and about 1.5 mm. 
     
     
         11 . The tube of  claim 2 , wherein the at least one disk comprises a fin height of between about 4 mm and about 25 mm. 
     
     
         12 . The tube of  claim 2 , wherein the at least one disk comprises between about 12 fin segments and about 100 fin segments. 
     
     
         13 . The tube of  claim 1 , wherein a tube outer diameter is between about 1 inch and about 2.5 inches. 
     
     
         14 . A heat recovery steam generator (HRSG) comprising at least one tube according to  claim 1 . 
     
     
         15 . The HRSG of  claim 14 , wherein at least about 10% of the tubes of the HRSG comprise the tube according to  claim 1 . 
     
     
         16 . The HRSG of  claim 15 , further comprising:
 at least one fin segment disposed in the at least one disk;   wherein the at least one disk wraps around the center tube in a spiral configuration,   wherein the at least one disk is bonded to the center tube via a high-frequency welding process,   wherein the at least one disk is at least partially composed of at least one of aluminum and copper,   wherein the center tube is at least partially composed of at least one of carbon steel, alloy steel, stainless steel, ferritic stainless, and austenitic stainless,   wherein the at least one disk comprises a thickness between about 0.5 mm and about 1.5 mm,   wherein the at least one disk comprises a fin height between about 4 mm and about 25 mm,   wherein the at least one disk comprises between about 12 fin segments and about 100 fin segments, and   wherein a tube outer diameter is between about 1 inch and about 2.5 inches.   
     
     
         17 . A method of forming a finned tube comprising:
 disposing a conductive sheet material adjacent to a steel tube;   winding the conductive sheet material around the steel tube; and   welding the conductive sheet material to the steel tube using a high frequency welding process;   wherein the frequency of the high frequency welding process is between about 450 kHz and 1200 kHz.   
     
     
         18 . The method of  claim 17 , further comprising serrating the conductive sheet material prior to disposing the conductive sheet material adjacent to the steel tube. 
     
     
         19 . The method of  claim 17 , wherein the conductive sheet material at least partially comprises at least one of aluminum and copper. 
     
     
         20 . The method of  claim 18 , further comprising:
 coating the steel tube with a rust inhibitor after welding the conductive sheet material to the steel tube using a high frequency welding process; and   heat treating the steel tube and conductive sheet material.