Fireplace heat exchanger

Abstract

An improved fireplace heat exchanger apparatus having one or more generally first hollow members, wherein each first member has an internally disposed second hollow member thereby creating an annular space between the interior surface of the first hollow member and the exterior surface of the second hollow member. Ducting is provided to direct air/gas flow through the heat exchanger in a controlled, counter-flow manner. The interior portion of the second hollow member is configured to accept a flow of a heat transfer medium for transferring heat energy to a desired location while the annular space is configured to accept a flow of hot combustion gasses from the combustion chamber and direct it toward a chimney. A nozzle disc located in the annular passageway proximate the inlet of hot combustion gasses causes the gasses to circulate within the annular passageway to enhance heat transfer to the second hollow member.

1 . A heat exchanger assembly for use in a fireplace having a combustion chamber, a chimney flue having an opening connected to a top portion of the combustion chamber, a heat source supported at a bottom portion of the combustion chamber for producing hot gasses in response to combustion, a front opening, a combustion air supply opening, and a fire screen assembly or the like for closing the front opening to separate the combustion chamber from a room area to be heated, the heat exchanger assembly comprising:
 a baffle for sealing the chimney opening, said baffle having at least one flue opening for exhausting combustion gasses into said chimney flue;   at least one elongate heat exchanger core having an outer hollow member with opposing combustion gas inlet and outlet ends separated by a outer member length, and an inner hollow member disposed within and generally coextensive with said outer hollow member forming an annular passageway therebetween, said inner hollow member having a medium inlet end and a medium outlet end, and further defining an interior passageway for a heat transfer medium flowing generally from said medium inlet end toward said medium outlet end, combustion gas flow within said annular passageway being generally in a counter-flow heat exchange relationship with said medium flow within said inner hollow member, receiving combustion gasses from said combustion chamber at said gas inlet end and discharging combustion gasses from said gas outlet end;   at least one nozzle disk positioned in said annular passageway and arranged to induce a swirling flow pattern of said combustion gasses about said inner hollow member generally between said combustion gas inlet and outlet ends; and   a supply conduit in flow communication with said medium inlet end for directing a flow of said heat transfer medium toward said medium inlet end of said inner hollow member and a return conduit in flow communication with said medium outlet end for receiving said heat transfer medium from said medium outlet end of said inner hollow member.   
   
   
       2 . The heat exchanger of  claim 1 , wherein said heat transfer medium is air. 
   
   
       3 . The heat exchanger of  claim 1 , wherein said heat transfer medium is a liquid, 
   
   
       4 . The heat exchanger assembly of  claim 1 , further comprising:
 at least one fluid crossover connecting a plurality of said inner hollow members thereby forming a continuous conduit through said plurality of inner hollow members, said continuous conduit receiving a flow of said heat transfer medium at an conduit inlet and discharging said flow from a conduit discharge, and   at least one combustion gas crossover connecting a plurality of said annular passageways thereby forming a continuous passageway through said plurality of annular passageways, said continuous passageway receiving a flow of said combustion gasses from said combustion chamber at a passageway inlet and discharging said combustion gasses from a passageway outlet generally toward said flue opening, flows of said heat transfer medium and said combustion gasses being in generally opposite directions in a counterflow heat exchange relationship.   
   
   
       5 . The heat exchanger assembly of  claim 1  further comprising an air supply distributor positioned below the heat source for directing combustion air flow from the combustion air supply opening toward the front opening. 
   
   
       6 . The heat exchanger assembly of  claim 1 , wherein said supply conduit and said return conduit are adjustable to fit fireplaces of various sizes. 
   
   
       7 . The heat exchanger assembly of  claim 6 , wherein a portion of said supply  2  and said return conduits is made of a flexible material. 
   
   
       8 . The heat exchanger assembly of  claim 1 , wherein said swirling flow pattern induced by said nozzle disk is in the same direction as that caused by the earth's Coriolis force. 
   
   
       9 . The heat exchanger assembly of  claim 1 , wherein at least one elongate heat exchanger core is generally vertically oriented to maximize the Goriolis effect. 
   
   
       10 . The heat exchanger assembly of  claim 1 , wherein said inner hollow member is made of aluminum. 
   
   
       11 . The heat exchanger assembly of  claim 1 , wherein said outer hollow member is made of steel. 
   
   
       12 . The heat exchanger assembly of  claim 1 , further comprising a radiant energy reflector positioned to reflect combustion flames toward the front opening. 
   
   
       13 . The heat exchanger assembly of  claim 4 , further comprising an air supply distributor positioned below the heat source for directing combustion air flow from the combustion air supply opening toward the front opening. 
   
   
       14 . The heat exchanger assembly of  claim 13 , wherein said swirling flow pattern induced by said nozzle disk is in the same direction as that caused by the earth's Coriolis force. 
   
   
       15 . The heat exchanger assembly of  claim 14 , wherein at least one elongate heat exchanger core is generally vertically oriented to maximize the Coriolis effect. 
   
   
       16 . The heat exchanger assembly of  claim 15 , wherein said supply conduit and said return conduit are adjustable to fit fireplaces of various sizes. 
   
   
       17 . The heat exchanger assembly of  claim 16 , wherein a portion of said supply and said return conduits are made of a flexible material. 
   
   
       18 . The heat exchanger assembly of  claim 17 , wherein said inner hollow member is made of aluminum. 
   
   
       19 . The heat exchanger assembly of  claim 18 , wherein said outer hollow member is made of steel. 
   
   
       20 . The heat exchanger assembly of  claim 19 , further comprising a radiant energy reflector positioned to reflect combustion flames toward the front opening. 
   
   
       21 . The heat exchanger of  claim 20 , wherein said heat transfer medium is air. 
   
   
       22 . The heat exchanger of  claim 20 , wherein said heat transfer medium is a liquid. 
   
   
       23 . A method of heating room air using a fireplace having a combustion chamber, a chimney flue having an opening connected to a top portion of the combustion chamber, a heat source supported at a bottom portion of the combustion chamber for producing hot gasses in response to combustion, a front opening, a combustion air supply opening, and a fire screen or the like for closing the front opening to separate the combustion chamber from a room area to be heated; the method comprising the steps.
 providing a baffle for sealing the chimney opening, the baffle having at least one flue opening for exhausting combustion gasses into the chimney flue;   to providing at least one elongate heat exchanger core having an outer hollow member with opposing combustion gas inlet and outlet ends separated by a outer member length, and an inner hollow member disposed within and generally coextensive with said outer hollow member forming an annular passageway therebetween, the inner hollow member having a medium inlet end and a medium outlet end, and further defining an interior passageway for a heat transfer medium flowing generally from the medium inlet end toward said medium outlet end, combustion gas flow within the annular passageway being generally in a counter-flow heat exchange relationship with the medium flow within the inner hollow member, receiving combustion gasses from the combustion chamber at the gas inlet end and discharging combustion gasses from the gas outlet end, and at least one nozzle disk positioned in the annular passageway proximate the combustion gas inlet to induce a swirling flow pattern of the combustion gasses about said inner hollow member generally between the combustion gas inlet and outlet ends,   providing a supply conduit in flow communication with the medium inlet end for directing a flow of the heat transfer medium toward the medium inlet end of the inner hollow member and a return conduit in flow communication with the medium outlet end for receiving the heat transfer medium from the medium outlet end of the inner hollow member and directing it toward a desired location to be heated;   providing a source of heat input to the fireplace in the form of a combustion process;   heating the air within the combustion chamber by the combustion process and passing the heated combustion gasses through the annular passageway with a swirling motion caused by the at least one nozzle disc; and   passing a heat transfer medium through the inner hollow member by way of the supply and return conduits, whereby relatively cool heat transfer medium supplied to the inner hollow member is heated and subsequently returned to the desired location to be heated.   
   
   
       24 . The method of  claim 19 , wherein the heat transfer medium is room air and the desired location to be heated is a room.