Heat exchanger for transferring heat between a coolant and a re-frigerant in a vehicle

Abstract

A heat exchanger for transferring heat between a coolant and refrigerant, the heat exchanger comprising a heating device for heating the refrigerant and the coolant, comprises a bottom wall forming an end-face end of a stack of at least two flow volumes through which the refrigerant or coolant flows, a first flow volume for the refrigerant to flow through, which first flow volume is adjacent to the bottom wall and is connected to a first fluid inlet and to a first fluid outlet, which are configured to produce a connection to a refrigerant circuit, the first flow volume additionally being defined by a first partition opposite the bottom wall, and a second flow volume for the coolant to flow through, which second flow volume is adjacent to the first partition and opposite the first flow volume and is connected to a second fluid inlet and to a second fluid outlet.

1 . A heat exchanger for transferring heat between a coolant and a refrigerant, the heat exchanger comprising a heating device for heating the refrigerant and the coolant, further comprising:
 a bottom wall forming an end-face end of a stack of at least two flow volumes through which at least one of: the refrigerant and the coolant flows;   a first flow volume for the refrigerant to flow through, which first flow volume is adjacent to the bottom wall and is connected to a first fluid inlet and to a first fluid outlet, which are configured to produce a connection to a refrigerant circuit, the first flow volume additionally being defined by a first partition opposite the bottom wall;   a second flow volume for the coolant to flow through, which second flow volume is adjacent to the first partition and opposite the first flow volume and is connected to a second fluid inlet and to a second fluid outlet, which are configured to produce a connection to a coolant circuit,   wherein the heating device is arranged on the bottom wall on a side opposite the first flow volume.   
     
     
         2 . The heat exchanger according to  claim 1 , wherein
 at least one first turbulator is installed in the first flow volume through which the refrigerant flows; and   at least one second turbulator is also installed in the second flow volume for the coolant to flow through.   
     
     
         3 . The heat exchanger according to  claim 2 , wherein,
 for the purpose of heat conduction from the bottom wall to the partition, the at least one first turbulator is secured both to the bottom wall and to the opposite first partition, by brazing.   
     
     
         4 . The heat exchanger according to  claim 3 , wherein
 the bottom wall and the first partition are arranged substantially parallel to each other, wherein a heat conduction direction extends perpendicular to the bottom wall and the partition, and   the bottom wall, based on its cross-sectional area perpendicular to the heat conduction direction, has a first heat conductivity value, and the at least one first turbulator, in the event of a plurality of first turbulators, the overall number of same, based on a cross-sectional area of the first flow volume perpendicular to the heat conduction direction, has a second heat conductivity value, wherein the second heat conductivity value of the at least one first turbulator, or corresponding to the overall number of the first turbulators, is 10% or more of the first heat conductivity value.   
     
     
         5 . The heat exchanger according to  claim 3 , wherein
 the at least one first turbulator has a lattice structure which is formed from a flat workpiece of a first wall thickness by accordion-like folding and has a lattice period.   
     
     
         6 . The heat exchanger according to  claim 5 , wherein
 a ratio of the lattice period to the first wall thickness is 20:1 or less.   
     
     
         7 . The heat exchanger according to  claim 2 , wherein
 at least two first turbulators are installed in the first flow volume for the refrigerant to flow through,   furthermore, at least one dividing wall extending between the bottom wall and the first partition, in the event of three first turbulators, two dividing walls extending between the bottom wall and the first partition, is or are included in the first flow volume, said dividing wall or walls dividing the first flow volume in such a way that the refrigerant flows sequentially through the at least two or three first turbulators from the first fluid inlet to the first fluid outlet.   
     
     
         8 . The heat exchanger according to  claim 7 , wherein
 a cross-sectional area which is defined in the partial volume of the first flow volume perpendicular to the respective flow direction, which partial volume is formed by the bottom wall, the first partition and the dividing walls and is filled by the respective first turbulators, increases in each case from the first fluid inlet to the first fluid outlet.   
     
     
         9 . The heat exchanger according to  claim 7 , wherein
 the at least two first turbulators have a lattice structure which is formed from a flat workpiece by accordion-like folding along a folding direction and has a lattice period,   the lattice structure in each case defines a preferred flow direction perpendicular to the folding direction, in which there is the least flow resistance, and   the at least two first turbulators are positioned in such a way that their respective preferred flow directions are oriented parallel to the respectively present flow direction of the refrigerant.   
     
     
         10 . The heat exchanger according to  claim 2 , wherein
 at least one second turbulator is also installed in the second flow volume for the coolant to flow through, the second turbulator having a lattice structure which is formed from a flat workpiece by accordion-like folding along a folding direction and has a lattice period,   the lattice structure in each case defines a preferred flow direction perpendicular to the folding direction, in which there is the least flow resistance, and   the second turbulator is positioned in such a way that its preferred flow direction is oriented perpendicular to a main flow direction of the coolant.   
     
     
         11 . The heat exchanger according to  claim 5 , wherein
 the second flow volume is limited by a second partition opposite the first partition,   a third flow volume for the refrigerant to flow through adjoins the second partition and is connected to the first fluid inlet and to the first fluid outlet, and   with reference to the third flow volume, a structure with at least one third turbulator is constructed in the same way as in the first flow volume,   wherein a third wall thickness of the third turbulator is less than the first wall thickness of the at least one first turbulator,   wherein, a ratio of the lattice period of the at least one third turbulator to the third wall thickness is more than 20:1.   
     
     
         12 . The heat exchanger according to  claim 2 , wherein
 the at least one second turbulator substantially fills the second flow volume, with the exception of two regions extending transversely to an imaginary connecting line between the second fluid inlet and the second fluid outlet directly at the fluid inlet and at the fluid outlet, respectively.   
     
     
         13 . The heat exchanger according to  claim 2 , wherein
 at least the at least one first turbulator is formed from an aluminium alloy, with at least one of: magnesium and silicon.   
     
     
         14 . The heat exchanger according to  claim 2 , wherein
 the fluid inlet and the fluid outlet for the first flow volume for the refrigerant to flow through are designed as connectors,   wherein at least the connector of the fluid inlet is provided with a receptacle for an expansion valve of the refrigerant circuit; and   wherein at least one of: the connector of the fluid inlet and the fluid outlet is provided with a receptacle for a temperature sensor.   
     
     
         15 . The heat exchanger according to  claim 1 , wherein
 the heating device comprises one or more heating elements having a heating conductor layer which is formed on the bottom wall or on a substrate attached thereto and in which heating strip conductors are formed.