Tubular high efficiency, non-contaminating fluid heater

A tubular high efficiency, non-contaminating fluid heater which minimizes fluid pressure drop therethrough and which minimizes fluid interstitial matrices and eliminates fluid stagnant zones which provide potential contamination sites comprising an elongate tubular member having a coil-like configuration and a substantially cylindrical sidewall which defines an elongate tubular chamber through which fluid is adapted to flow, said tubular member including an inlet at one end thereof for receiving fluid to be heated and an outlet at the other end thereof and through which heated fluid is adapted to exit the tubular member, a plurality of elongate electrical resistance heaters located in said elongate tubular chamber for heating the fluid as the fluid passes through the tubular chamber, each of said elongate resistance heaters being sheathed in a substantially inert sheath, each of said elongate resistance heaters having a coil-like configuration which extends through said elongate tubular chamber and heater end portions at each end thereof, each of said heater end portions having a streamlined generally arcuate configuration substantially parallel to the direction of fluid flow which extends through said sidewall of said tubular member at each end of said elongate electrical resistance heaters, said streamlined generally arcuate configuration of said heater end portions substantially eliminating interstitial matrices in the fluid flow adjacent the ends of said elongate electrical resistance heaters which extend through said sidewall of said tubular member and any stagnant zones and wherein fluid flow from said inlet to said outlet through said tubular chamber is substantially high velocity, turbulent fluid flow having a Reynolds number greater than 4,000, which brings the fluid into intimate contact with said electrical resistance heaters and which scavenges said cylindrical sidewall of said tubular member, said electrical resistance heaters and said inlet and outlet, to prevent contaminates from accumulating within said fluid heater, a plurality of power conductors, each of which is connected to a different heater end portion of said plurality of electrical resistance heaters, each power conductor being connected to the respective heater end portion adjacent the exterior of said substantially cylindrical sidewall of said tubular member, and further including a sealed chamber disposed adjacent to said exterior of said substantially cylindrical sidewall of said tubular member at each end thereof, said connection of said power conductor to said heater portions at each end of the tubular member being located within said sealed chambers to prevent moisture from contacting said heater end portions, said sealed chambers including electrical insulation means therein to prevent the transfer of electrical power from said connection of said power conductors and said heater end portions externally of said sealed chamber.

A tubular high efficiency, non-contaminating fluid heater which minimizes fluid pressure drop therethrough and which minimizes fluid interstitial matrices and eliminates stagnant zones which provide potential contamination sites comprising an elongate tubular member having a coil-like configuration and a substantially cylindrical sidewall which defines an elongate tubular chamber through which fluid is adapted to flow, said tubular member including an inlet at one end thereof for receiving fluid to be heated and an outlet at the other end thereof and through which heated fluid is adapted to exit the tubular member, a plurality of elongate electrical resistance heaters located in said elongate tubular chamber for heating the fluid as the fluid passes through the tubular chamber, each of said elongate resistance heaters having a coil-like configuration which extends through said elongate tubular chamber and a heater end portion at one end thereof, each of said heater end portions having a streamlined generally arcuate configuration substantially parallel to the direction of fluid flow which exits through an opening in said sidewall of said tubular member at one end of said elongate electrical resistance heaters, each of said heater end portions being secured to said sidewall of said tubular member adjacent said opening to rigidly secure said heater end portions and to seal said opening in said sidewall, said streamlined generally arcuate configuration of said heater end portions substantially eliminating interstitial matrices and eliminating stagnant zones in the fluid flow adjacent the ends of said elongate electrical resistance heaters which extend through said sidewall of said tubular member, a differential pressure switch for sensing the difference in fluid pressure between said inlet and said outlet for said fluid chamber, and a flow switch for sensing fluid flow through said elongate tubular chamber, said switches being adapted to energize said electrical resistance heaters in response to turbulent fluid flow through said tubular chamber, said switches being further adapted to sense a predetermined fluid flow rate which is not turbulent through said tubular chamber and de-energize said electrical resistance heaters in response to said switches sensing said predetermined fluid flow rate which is not turbulent, and wherein fluid flow from said inlet to said outlet through said tubular chamber is substantially high velocity, turbulent fluid flow having a Reynolds number greater than 4,000 which brings the fluid into intimate contact with said electrical resistance heaters and which scavenges said cylindrical sidewall of said tubular member and said electrical resistance heaters to prevent contaminates from accumulating within said fluid heater.

A tubular high efficiency, non-contaminating fluid heater which minimizes fluid pressure drop therethrough and which minimizes fluid interstitial matrices and eliminates stagnant zones which provide potential contamination sites comprising an elongate tubular member having a coil-like configuration and a substantially cylindrical sidewall which defines an elongate tubular chamber through which fluid is adapted to flow, said tubular member including an inlet at one end thereof for receiving fluid to be heated and an outlet at the other end thereof and through which heated fluid is adapted to exit the tubular member, a plurality of elongate electrical resistance heaters located in said elongate tubular chamber for heating the fluid as the fluid passes through the tubular chamber, each of said elongate resistance heaters having a coil-like configuration which extends through said elongate tubular chamber and a heater end portion at one end thereof, each of said heater end portions having a streamlined generally arcuate configuration substantially parallel to the direction of fluid flow which extends through an opening in said sidewall of said tubular member at one end of said elongate electrical resistance heaters, each of said heater end portions being secured to said sidewall of said tubular member adjacent said opening to rigidly secure said heater end portion and to seal said opening in said sidewall, said streamlined generally arcuate configuration of said heater end portions substantially eliminating interstitial matrices and eliminating stagnant zones in the fluid flow adjacent the ends of said elongate electrical resistance heaters which extend through said sidewall of said tubular member and wherein fluid flow from said inlet to said outlet through said tubular chamber is substantially high velocity, turbulent fluid flow which brings the fluid into intimate contact with said cylindrical resistance heaters and which scavenges said cylindrical sidewall of said tubular member and said electrical resistance heaters to prevent contaminates from accumulating within said fluid heater, further including a plurality of power conductors, each of which is connected to said heater end portion of different ones of said plurality of electrical resistance heaters, said power conductors being connected to said heater end portions adjacent the exterior of said substantially cylindrical sidewall of said tubular member, and a sealed chamber disposed adjacent to said exterior of said substantially cylindrical sidewall of said tubular member, said connection of said power conductors at one end thereof to said heater end portions being located within said sealed chamber to prevent moisture from contacting said heater end portions, said sealed chamber including electrical insulation means therein to prevent the transfer of electrical power from said connection of said power conductors and said heater end portions externally of said sealed chamber.