Evaporator

Abstract

An evaporator ( 10 ) includes a substantially plate-like body member ( 12 ) defining an operatively outer surface ( 14 ) and an operatively inner surface ( 16 ), both surfaces ( 14, 16 ) being substantially smooth to inhibit detritus from attaching to the body member ( 12 ). The body member ( 12 ) is shaped to cause incoming fluid from which heat is to be extracted, in use, to follow an extended, circuitous path past the body member ( 12 ) initially along the outer (surface 14 ) of the body member ( 12 ) prior to the fluid impinging on the inner surface ( 16 ) of the body member ( 12 ).

1 . An evaporator which includes a substantially plate-like body member defining an operatively outer surface and an operatively inner surface, both surfaces being substantially smooth to inhibit detritus from attaching to the body member and the body member being shaped to cause incoming fluid from which heat is to be extracted, in use, to follow an extended, circuitous path past the body member initially along the outer surface of the body member prior to the fluid impinging on the inner surface of the body member. 
     
     
         2 . The evaporator of  claim 1  in which the body member comprises a pair of opposed side members interconnected by a bridging portion. 
     
     
         3 . The evaporator of  claim 2  in which at least the bridging portion is curved so that, when viewed in plan, the body member has a substantially U-shape or horseshoe shape. 
     
     
         4 . The evaporator of  claim 2  in which, when viewed in plan, the body member is substantially symmetrical about a centre line, extending substantially in the direction of the side members, bisecting the body member. 
     
     
         5 . The evaporator of  claim 1  which includes a flow directing member for directing the incoming fluid into contact with the outer surface of the body member at an upstream end of the body member. 
     
     
         6 . The evaporator of  claim 5  in which the body member has a pair of spaced ends and in which the flow directing member is attachable to either one of the ends of the body member. 
     
     
         7 . The evaporator of  claim 1  in which the body member has a height exceeding a maximum height of a body of the incoming fluid, in use, to inhibit detritus carried in the fluid being ensnared on the body member. 
     
     
         8 . The evaporator of  claim 1  in which the body member is formed from a pair of sheets of a corrosive resistant material secured together and defining passages for a working fluid, the passages extending predominantly in a direction of movement of the incoming fluid past the body member. 
     
     
         9 . An evaporator which includes
 a substantially plate-like body member defining an operatively outer surface and an operatively inner surface and a pair of spaced ends, both surfaces being substantially smooth to inhibit detritus from attaching to the body member, the body member comprising a pair of opposed side members interconnected by a bridging portion, the body member being formed from a pair of sheets of a corrosive resistant material secured together and defining passages for a working fluid, the passages extending predominantly in a direction of movement of the incoming fluid past the body member; and   a flow directing member attached to an end of the body member, the flow directing member directing incoming fluid into contact with the outer surface of the body member at an upstream end of the body member.   
     
     
         10 . The evaporator of  claim 9  in which the passages of the body member are formed by blowing a fluid through the body member to inhibit formation of sharp edges or sharp transitions in passage walls of the body member. 
     
     
         11 . The evaporator of  claim 9  in which the flow directing member is removably attached to the end of the body member, the flow directing member being configured to be attachable to either end of the body member so that either end of the body member can function as the upstream end in use, 
     
     
         12 . An evaporator assembly which includes
 a collection tank defining a detention chamber for incoming fluid from which heat is to be extracted;   an evaporator, as claimed in  claim 1 , received in the detention chamber, the collection tank having an inlet opening and an opposed discharge opening, at least the discharge opening being arranged at a height relative to the evaporator lower than an upper edge of the body member of the evaporator; and   a conduit interconnecting a region of the tank at its operatively lowest point and the discharge opening to inhibit the incoming fluid from overflowing the upper edge of the body member of the evaporator.   
     
     
         13 . The assembly of  claim 12  in which the collection tank defines a sump which defines the lowest point of the tank, the body member of the evaporator being arranged about the sump substantially to isolate the sump from the inlet opening of the tank. 
     
     
         14 . The assembly of  claim 12  in which at least a part of a floor of the collection tank is angled to encourage the formation of eddies in the incoming fluid to cause heat exchange by convection as well as by thermal conduction. 
     
     
         15 . The assembly of  claim 12  in which the conduit is a snorkel member removably attachable to the discharge opening. 
     
     
         16 . The assembly of  claim 12  in which both the collection tank and the evaporator are symmetrical so that either opening of the collection tank can be used as the inlet opening with the other opening then functioning as the discharge opening. 
     
     
         17 . The assembly of  claim 12  in which the body member of the evaporator has a pair of spaced ends and in which the assembly includes a flow directing member attachable to either one of the ends of the body member, the flow directing member being arranged adjacent the inlet opening for directing the incoming fluid into heat exchange contact with the outer surface of the body member. 
     
     
         18 . (canceled) 
     
     
         19 . An evaporator assembly which includes
 a collection tank defining a detention chamber for incoming fluid from which heat is to be extracted;   an evaporator, as claimed in  claim 9 , received in the detention chamber, the collection tank having an inlet opening and an opposed discharge opening, at least the discharge opening being arranged at a height relative to the evaporator lower than an upper edge of the body member of the evaporator; and   a conduit interconnecting a region of the tank at its operatively lowest point and the discharge opening to inhibit the incoming fluid from overflowing the upper edge of the body member of the evaporator.