Plate heat exchanger with dual flow path

Abstract

A plate heat exchanger includes a plurality of main plates stacked to define a first cavity to direct a first fluid therethrough and a second cavity to direct a second fluid therethrough, the second fluid different from and kept separated from the first fluid, and an intermediate plate located in the second cavity between adjacent main plates, the second fluid directed across both sides of the intermediate plate.

What is claimed is: 
     
         1 . A plate heat exchanger comprising:
 a plurality of main plates stacked to define a first cavity to direct a first fluid therethrough and a second cavity to direct a second fluid therethrough, the second fluid different from and kept separated from the first fluid; and   an intermediate plate located in the second cavity between adjacent main plates, the second fluid directed across both sides of the intermediate plate.   
     
     
         2 . The plate heat exchanger of  claim 1 , further comprising one or more surface enhancements disposed at the intermediate plate to induce vortices in the second fluid. 
     
     
         3 . The plate heat exchanger of  claim 2 , wherein the one or more surface enhancements are one or more of material deformation at the intermediate plate or material removal from the intermediate plate. 
     
     
         4 . The plate heat exchanger of  claim 1 , wherein the main plates include a plurality of ridges and troughs, defining at least one main plate peak and at least one main plate valley. 
     
     
         5 . The plate heat exchanger of  claim 4 , wherein the intermediate plate includes a plurality of ridges and troughs, defining at least one intermediate plate peak and at least one intermediate plate valley. 
     
     
         6 . The plate heat exchanger of  claim 5 , wherein a pitch between adjacent intermediate plate peaks differs from a pitch between adjacent main plate peaks. 
     
     
         7 . The plate heat exchanger of  claim 6 , wherein the pitch between adjacent intermediate plate peaks is greater than a pitch between adjacent main plate peaks. 
     
     
         8 . The plate heat exchanger of  claim 6 , wherein the pitch between adjacent intermediate plate peaks is greater than a pitch between adjacent main plate peaks. 
     
     
         9 . The plate heat exchanger of  claim 4 , wherein an amplitude between adjacent intermediate plate peaks and intermediate plate valleys differs from an amplitude between adjacent main plate peaks and main plate valleys. 
     
     
         10 . The plate heat exchanger of  claim 9 , wherein the amplitude between adjacent intermediate plate peaks and intermediate plate valleys is greater than an amplitude between adjacent main plate peaks and main plate valleys. 
     
     
         11 . The plate heat exchanger of  claim 9 , wherein the amplitude between adjacent intermediate plate peaks and intermediate plate valleys is less than an amplitude between adjacent main plate peaks and main plate valleys. 
     
     
         12 . The plate heat exchanger of  claim 1 , further comprising a second intermediate plate disposed in the first cavity. 
     
     
         13 . The plate heat exchanger of  claim 1 , wherein a first flow direction of the second fluid at a first side of the intermediate plate is the same as a second flow direction of the second fluid at a second side of the intermediate plate. 
     
     
         14 . The plate heat exchanger of  claim 1 , wherein a first flow direction of the second fluid at a first side of the intermediate plate is different from a second flow direction of the second fluid at a second side of the intermediate plate. 
     
     
         15 . A plate heat exchanger comprising:
 a plurality of main plates stacked to define a first cavity to direct a first fluid therethrough and a second cavity to direct a second fluid therethrough, the second fluid different from and kept separated from the first fluid, each main plate of the plurality of main plates including a plurality of ridges and troughs, defining at least one main plate peak and at least one main plate valley; and   an intermediate plate located in the second cavity between adjacent main plates, the intermediate plate including a plurality of ridges and troughs, defining at least one intermediate plate peak and at least one intermediate plate valley;   wherein one or more of a pitch between adjacent intermediate plate peaks differs from a pitch between adjacent main plate peaks or an amplitude between adjacent intermediate plate peaks and intermediate plate valleys differs from an amplitude between adjacent main plate peaks and main plate valleys.   
     
     
         16 . The plate heat exchanger of  claim 15 , wherein the pitch between adjacent intermediate plate peaks is greater than a pitch between adjacent main plate peaks. 
     
     
         17 . The plate heat exchanger of  claim 15 , wherein the amplitude between adjacent intermediate plate peaks and intermediate plate valleys is greater than an amplitude between adjacent main plate peaks and main plate valleys. 
     
     
         18 . The plate heat exchanger of  claim 15 , further comprising one or more surface enhancements disposed at the intermediate plate to induce vortices in the second fluid. 
     
     
         19 . The plate heat exchanger of  claim 18 , wherein the one or more surface enhancements are one or more of material deformation at the intermediate plate or material removal from the intermediate plate.