High thermal transfer spiral flow heat exchanger

Abstract

A fluid heating system with a heat exchanger includes an elongated cylindrical tube with an inlet end and an opposed end. An array of film resistive elements is positioned on the outer surface of the cylindrical tube and extends circumferentially at least partially around the outer surface. A spiral channel guide is coaxially positioned within the cylindrical tube so as to force fluid flowing in the tube into a spiral path at least partially against an inner surface of the cylindrical tube. The spiral channel guide directs fluid flowing in the cylindrical tube so as to cause turbulence to occur in the flow and increase thermal transfer from the inner surface of the cylindrical tube to the fluid flowing in the tube.

1 . A fluid heating system with a heat exchanger comprising:
 an elongated cylindrical tube with an outer surface, an inner surface, an inlet end and an opposed end;   an array of film resistive elements positioned on the outer surface of the cylindrical tube and extending circumferentially at least partially around the outer surface; and   a spiral channel guide coaxially positioned within the cylindrical tube so as to force fluid flowing in the tube into a spiral path at least partially against the inner surface of the cylindrical tube.   
     
     
         2 . A fluid heating system with a heat exchanger as claimed in  claim 1  wherein the array of film resistive elements includes a plurality of separate groups of film resistive elements. 
     
     
         3 . A fluid heating system with a heat exchanger as claimed in  claim 1  wherein the array of film resistive elements includes a film conductor formed on the outer surface of the cylindrical tube with a predetermined depth and width. 
     
     
         4 . A fluid heating system with a heat exchanger as claimed in  claim 1  wherein the spiral channel guide includes a central elongated cylindrical core and a fluid diverter extending along an outer surface of the cylindrical core. 
     
     
         5 . A fluid heating system with a heat exchanger as claimed in  claim 4  wherein the fluid diverter is one of an integral part of the outer surface of the cylindrical core and an element affixed to the outer surface of the central core. 
     
     
         6 . A fluid heating system with a heat exchanger as claimed in  claim 4  wherein the fluid diverter has an outer diameter substantially the same as an inner diameter of the cylindrical tube. 
     
     
         7 . A fluid heating system with a heat exchanger as claimed in  claim 4  wherein the fluid diverter is in the form of a continuous spiral. 
     
     
         8 . A fluid heating system with a heat exchanger as claimed in  claim 1  further including one of an inlet manifold and an inlet/outlet manifold positioned in the inlet end of the cylindrical tube. 
     
     
         9 . A fluid heating system with a heat exchanger as claimed in  claim 8  further including one of an outlet manifold and a reversing header positioned in the outlet end of the cylindrical tube. 
     
     
         10 . A fluid heating system with a heat exchanger as claimed in  claim 1  further including a process controller unit connected to the array of film resistive elements and adapted to be connected to an electrical supply, the process controller unit for energizing the array of film resistive elements. 
     
     
         11 . A fluid heating system with a heat exchanger comprising:
 an elongated cylindrical tube with an outer surface, an inner surface, an inlet end and an opposed end;   an array of film resistive elements positioned on the outer surface of the cylindrical tube and extending circumferentially at least partially around the outer surface;   a spiral channel guide including a central elongated cylindrical core and a fluid diverter extending along an outer surface of the cylindrical core, the spiral channel guide coaxially positioned within the cylindrical tube so as to force fluid flowing in the tube into a spiral path at least partially against the inner surface of the tube; and   one of an inlet manifold and an inlet/outlet manifold positioned in the inlet end of the cylindrical tube to introduce fluid into the cylindrical tube and one of an outlet manifold and a reversing header positioned in the opposing end to one of conduct fluid from the cylindrical tube and reverse the flow of fluid within the cylindrical tube, respectively.   
     
     
         12 . A fluid heating system with a heat exchanger as claimed in  claim 11  wherein the fluid diverter is one of an integral part of the outer surface of the cylindrical core and an element affixed to the outer surface of the central core. 
     
     
         13 . A fluid heating system with a heat exchanger as claimed in  claim 11  wherein the fluid diverter has an outer diameter substantially the same as an inner diameter of the cylindrical tube. 
     
     
         14 . A fluid heating system with a heat exchanger as claimed in  claim 11  wherein the fluid diverter is in the form of a continuous spiral. 
     
     
         15 . A fluid heating system with a heat exchanger as claimed in  claim 11  further including a process controller unit connected to an electrical supply for energizing the array of film resistive elements. 
     
     
         17 . A fluid heating system with a heat exchanger comprising:
 an elongated cylindrical tube with an outer surface, an inner surface, an inlet end and an opposed end;   an array of film resistive elements positioned on the outer surface of the cylindrical tube and extending circumferentially at least partially around the outer surface;   a spiral channel guide including a central elongated cylindrical core and a fluid diverter extending along an outer surface of the cylindrical core, the spiral channel guide coaxially positioned within the cylindrical tube so as to force fluid flowing in the tube into a spiral path at least partially against the inner surface of the tube;   one of an inlet manifold and an inlet/outlet manifold positioned in the inlet end of the cylindrical tube to introduce fluid into the cylindrical tube and one of an outlet manifold and a reversing header positioned in the opposing end to one of conduct fluid from the cylindrical tube and reverse the flow of fluid within the cylindrical tube, respectively;   a plurality of temperature sensors positioned in the fluid flow within the cylindrical tube;   a flow sensor positioned adjacent the inlet end of the cylindrical tube; and   a process controller unit connected to receive a flow signal from the flow sensor and programmed to calculate a flow rate, the process controller unit further connected to receive temperature signals from the plurality of temperature sensors and further programmed to determine from the temperature signals the amount of power necessary to heat fluid from a source temperature adjacent the inlet end, at the calculated flow rate, to a specified temperature adjacent the outlet manifold and control energization of the film resistive elements to achieve the specified temperature.   
     
     
         18 . A fluid heating system with a heat exchanger as claimed in  claim 17  wherein the spiral channel guide directs fluid flowing in the cylindrical tube to cause turbulence to occur in the flow and increase thermal transfer from the inner surface of the cylindrical tube to the fluid flowing in the tube. 
     
     
         19 . A fluid heating system with a heat exchanger as claimed in  claim 17  wherein the array of film resistive elements includes a plurality of separate groups of film resistive elements, at least some of the separate groups including different numbers of film resistive elements. 
     
     
         20 . A fluid heating system as claimed in  claim 19  wherein an electrical supply is coupled to the process controller unit from a three (3) phase source and phase-to-phase loading is balanced to within the value of a smallest number of the different numbers of film resistive elements. 
     
     
         21 . A fluid heating system as claimed in  claim 20  wherein the process controller unit monitor includes means for coupling an electrical supply to the process controller unit and means for adjusting energization of the array of film resistive elements in response to the monitored voltage. 
     
     
         22 . A fluid heating system as claimed in  claim 20  further including a communication interface configured to provide access to a Power Management Controller.