Heat transfer plate

Abstract

A heat transfer plate comprising a number of rows of alternating ridges and grooves, where a transition between each ridge and the adjacent groove in the same row is formed by a portion of the heat transfer plate that is inclined relative the central plane, and a central opening that is configured to receive a fluid separation device, such that a first part of the central opening may act as a fluid inlet and a second part of the central opening may act as a fluid outlet, wherein the plate comprises plate portions that extend between the rows of ridges and grooves such that the rows are separated from each other.

1 . A heat transfer plate configured to be arranged in a plate heat exchanger, the heat transfer plate comprising
 a number of rows where each row has alternating ridges and grooves that extend along a central plane of the heat transfer plate, between a top plane and a bottom plane of the heat transfer plate, the top plane and bottom plane being substantially parallel to the central plane and located on a respective side of the central planed, where a transition between each ridge and adjacent groove in the same row is formed by a portion of the heat transfer plate that is inclined relative the central plane, and   a central opening that is configured to receive a fluid separation device, such that a first part of the central opening may act as a fluid inlet and a second part of the central opening may act as a fluid outlet, characterized by   plate portions that extend along the central plane of the heat transfer plate, between the rows of ridges and grooves such that the rows are separated from each other.   
     
     
         2 . A heat transfer plate according to  claim 1 , wherein a contact area of a top surface of a number of the ridges, on a top side of the heat transfer plate, is larger than a contact area of a bottom surface of a number of the grooves, on a bottom side of the heat transfer plate. 
     
     
         3 . A heat transfer plate according to  claim 1 , wherein a number of the rows of alternating ridges and grooves extend in a tangential direction of the heat transfer plate. 
     
     
         4 . A heat transfer plate according to  claim 1 , wherein a number of the rows of alternating ridges and grooves extend in a radial direction of the heat transfer plate. 
     
     
         5 . A heat transfer plate according to  claim 1 , comprising a number of sections of rows of alternating ridges and grooves, wherein an inner section of the sections provides a higher flow resistance than an outer section of the sections, the inner section being arranged closer to the central opening than the outer section. 
     
     
         6 . A heat transfer plate according to  claim 5 , wherein the inner section has a higher tangential flow resistance than the outer section. 
     
     
         7 . A heat transfer plate according to  claim 5 , comprising a first, geometrical center axis that extends across the first part of the central opening, through a center of the heat transfer plate and across the second part of the central opening, and a second, geometrical center axis that is perpendicular to the first center axis and extends through the center, wherein the inner section is, as seen along a direction parallel to the second center axis, arranged closer to the central opening than the outer section. 
     
     
         8 . A heat transfer plate according to  claim 5 , wherein the rows of alternating ridges and grooves of the inner section have a different pitch than the rows of alternating ridges and grooves of the outer section. 
     
     
         9 . A heat transfer plate according to  claim 5 , wherein any of the inner section and the outer section has the shape of a bent rectangle. 
     
     
         10 . A heat transfer plate according to  claim 1 , comprising
 a first baffle and a second baffle that are arranged on a respective side of the first part of the central opening, and   a third baffle and a fourth baffle that are arranged on a respective side of the second part of the central opening, wherein   each of the baffles has an extension in a radial direction of the heat transfer plate.   
     
     
         11 . A heat transfer plate according to  claim 1 , comprising
 a peripheral edge with a first part that may act as a fluid inlet and a second part that may act as a fluid outlet, wherein   sections of the peripheral edge that are located intermediate the first part and the second part of the peripheral edge are configured to be sealed with corresponding sections of a similar heat transfer plate that is located at a top side of the heat transfer plate, and   sections of the central opening that are located intermediate the first part and the second part of the central opening are configured to be sealed with corresponding sections of a similar heat transfer plate that is located at a bottom side of the heat transfer plate.   
     
     
         12 . A heat exchanger comprising a number of heat transfer plates according to  claim 1 , a casing that forms a sealed enclosure, and a separation device arranged in central openings of the heat transfer plates, such that the central openings may act both as a fluid inlet and a fluid outlet, wherein the heat transfer plates are permanently joined and arranged in the sealed enclosure such that alternating first and second flow paths for a first and a second fluid are formed in between the heat transfer plates. 
     
     
         13 . A heat exchanger according to  claim 12 , wherein the distance between the central planes of at least two adjacent heat transfer plates is smaller at inner sections of the heat transfer plates than at outer sections of the heat transfer plates, the inner sections being arranged closer to the central opening than the outer sections. 
     
     
         14 . A heat exchanger according to  claim 12 , wherein the heat transfer plate comprises
 a central edge that is folded towards and joined with a corresponding folded, central edge of an adjacent heat transfer plate, and a peripheral edge that is folded towards and joined with a corresponding folded, peripheral edge of another, adjacent heat transfer plate.   
     
     
         15 . A method of operating a heat exchanger according to  claim 12 , wherein
 a first fluid enters the first fluid path via a first part of the central opening, flows over the heat transfer plates while making a 180° turn, and exits the first fluid path via a second part of the central opening, the first fluid thereby having a flow direction when exiting the first fluid path that is opposite the flow direction it had when entering the first fluid path,   a second fluid enters the second fluid path via a first part of a peripheral edge that acts as a fluid inlet, flows over the heat transfer plates, and exits the second fluid path via a second part of the peripheral edge.   
     
     
         16 . A method according to  claim 15 , wherein the first fluid makes a 180° turn only, and the second fluid flows directly from the first part to the second part of the peripheral edge. 
     
     
         17 . A method according to  claim 15 , wherein fluid is passed through the central opening and into the first fluid path at a pressure that is lower than a pressure of a fluid that is passed into the second fluid path.