Heat exchanger

Abstract

A multi-plate dual flow path heat exchanger includes a plurality of stacked plates 70 each having a central section 71 provided with a number of longitudinal channels 72 separated by upstanding zig-zag walls 75, the channels 72 being provided on their floors 72 A with ridges 74, the floors and the ridges being of undulating form along the flow paths. Shallow ribs 75 extend laterally across the flow paths and in combination with the undulations assist in disruption of boundary layer flow.

1 . A heat exchanger including a plurality of plate members stacked parallel above one another to define two separate fluid flow paths between alternate pairs of adjacent plate members wherein each plate member has an undulating surface along the respective fluid flow path sufficient to reduce the boundary layer effect and wherein each plate member has a series of laterally-extending surface formations along the flow paths.  
     
     
         2 . A heat exchanger according to  claim 1  wherein each laterally-extending formation is in the form of a shallow rib.  
     
     
         3 . A heat exchanger according to  claim 1  wherein each laterally-extending formation is no more than 1 mm in height.  
     
     
         4 . A heat exchanger according to  claim 1  wherein the surface of each plate member is textured.  
     
     
         5 . A heat exchanger according to  claim 1  wherein each plate member is formed with a plurality of channels defined between upwardly projecting walls and providing floors therebetween.  
     
     
         6 . A heat exchanger according to  claim 5  wherein each channel is provided with a plurality of equi-spaced ridges upstanding from the floor and extending in parallel and longitudinally along the channel between the walls and being of lower height than the walls, the ridges and the floor of each channel undulating along the length thereof.  
     
     
         7 . A heat exchanger according to  claim 6  wherein the undulations in the floor and the ridges are of shallow and multiple form to provide a plurality of hills and valleys along each channel.  
     
     
         8 . A heat exchanger according to  claim 5  wherein the upwardly projecting walls bounding the channels are of zig-zag form in the longitudinal direction of the plate members.  
     
     
         9 . A heat exchanger according to  claim 8  wherein the zig-zag formations are offset as between one plate member and an adjacent plate member.  
     
     
         10 . A heat exchanger according to  claim 6  wherein the support members are provided on at least one ridge in each channel and are upstanding therefrom and are adapted to support an adjacent plate member.  
     
     
         11 . A heat exchanger according to  claim 6  wherein the support members are disposed at spaced intervals longitudinally of the ridges.  
     
     
         12 . A heat exchanger according to  claim 11  wherein the support members are formed of the material of the plate member and are in the form of elongate projections extending parallel to the direction of fluid flow.  
     
     
         13 . A heat exchanger according to  claim 10  wherein support members are provided on more than one ridge and the support members on one ridge are offset from those on the other ridge.  
     
     
         14 . A heat exchanger according to  claim 10  wherein the support members on one plate member are offset from the support members on an adjacent plate member.  
     
     
         15 . A heat exchanger according to  claim 1  wherein triangular regions at opposite ends providing adjacent inlet and outlet faces inclined relative to one another and meeting at an apex.  
     
     
         16 . A heat exchanger according to  claim 15  wherein at least one elongate resilient member extending vertically along the apex and having fingers interdigitated between plate members, the exchanger having elongate clamping members extending along opposite sides of the or each resilient member and compressing the or each resilient member therebetween.  
     
     
         16 . A heat exchanger including a plurality of plate members stacked parallel above one another to define two separate fluid flow paths between alternate pairs of adjacent plate members wherein each plate member has an undulating surface along the respective fluid flow path and is textured and wherein each plate member has a series of laterally-extending ribs.  
     
     
         17 . A heat exchanger including a plurality of plate members stacked parallel above one another to define two separate fluid flow paths between alternate pairs of adjacent plate members wherein each plate member is formed with a plurality of channels defined between upwardly projecting walls and providing floors therebetween, each channel is provided with a plurality of equi-spaced ridges upstanding from the floor and extending in parallel and longitudinally along the channel between the walls and being of lower height than the walls, the ridges and the floors of each channel undulating along the length thereof, and wherein each plate member has a series of laterally-extending ribs.