System and method for dynamic control of a heat exchanger

Abstract

The present application relates to a system for dynamic control of the operation of a heat exchanger, the system comprising a heat exchanger, a plurality of injector arrangements, a local sensor arrangement, and a controller, wherein the local sensor arrangement comprises a plurality of local temperature sensors being arranged to measure temperature values; and wherein the controller is arranged to determine a difference between the measured temperature values and is further arranged to communicate with the valves of the plurality of injector arrangements to adjust the local amount of first fluid supplied by at least one of the injector arrangements in order to even out the determined difference. The application also relates to a method for the dynamic control of the operation of a heat exchanger in such a system.

1 . A system for dynamic control of the operation of a heat exchanger, the system comprising a heat exchanger, a plurality of injector arrangements, a local sensor arrangement, and a controller, wherein
 the heat exchanger comprises a first global outlet, a first plurality of fluid passages, each fluid passage comprising a local inlet and a local outlet, for the supply of a first fluid to the first global outlet via the first plurality of fluid passages during evaporation of the first fluid;   the heat exchanger further comprises a second global outlet, a second plurality of fluid passages, each fluid passage comprising a local inlet and a local outlet, for the supply of a second fluid to the second global outlet via the second plurality of fluid passages;   the first fluid passages and the second fluid passages are arranged separated from each other and side-by-side, in order to enable heat exchange between the first fluid in the first plurality of fluid passages and the second fluid in the second plurality of fluid passages;   each injector arrangement comprises at least one valve, and each injector arrangement is arranged to supply a flow of the first fluid to the local inlet of at least one of the first plurality of fluid passages;   the local sensor arrangement comprises a plurality of local temperature sensors being arranged to measure temperature values corresponding to the local temperature of the evaporated first fluid flowing nearby the local outlets of the first plurality of fluid passages;   the controller is arranged to determine a difference between the measured temperature values received from the local sensor arrangement and is further arranged to communicate with the valves of the plurality of injector arrangements to adjust the local amount of first fluid supplied by at least one of the injector arrangements in order to even out the determined difference.   
     
     
         2 . The system according to  claim 1 , wherein the plurality of local temperature sensors in the local sensor arrangement are arranged nearby the local outlets of the first plurality of fluid passages. 
     
     
         3 . The system according to  claim 1 , wherein the plurality of local temperature sensors in the local sensor arrangement are arranged nearby the local outlets of the second plurality of fluid passages. 
     
     
         4 . The system according to  claim 1 , wherein the controller is further arranged to determine a compensating local adjustment of the local amount of first fluid supplied by the other than the at least one of the injector arrangements such that the global amount of first fluid in the first plurality of first passages remains the same, and communicate the determined compensating local adjustment to said other than the at least one of the injector arrangements. 
     
     
         5 . The system according to  claim 1 , wherein the controller is arranged to determine the difference by at least determining the standard deviation for the measured temperature values. 
     
     
         6 . The system according to  claim 1 , wherein the first fluid is refrigerant and the second fluid comprises water. 
     
     
         7 . The system according to  claim 1 , wherein the controller is a PI regulator or a PID regulator. 
     
     
         8 . The system according to  claim 1 , wherein
 the system further comprises a global sensor arrangement being arranged to measure the global temperature and the global pressure, or the presence of any liquid content, of the evaporated first fluid downstream from the first global outlet;   the controller is arranged to communicate with the valves of the plurality of injector arrangements, or with a global valve, to control, based on information received from the global sensor arrangement, the global amount of the first fluid to be supplied to the first plurality of fluid passages in order for the heat exchanger to operate towards a set-point superheating value.   
     
     
         9 . The system according to  claim 8 , wherein the global sensor arrangement comprises a global pressure sensor and a global temperature sensor. 
     
     
         10 . Use of a system according to  claim 1 . 
     
     
         11 . A method for dynamic control of the operation of a heat exchanger in a system according to  claim 1 , the method comprising:
 a) supplying, by the plurality of injector arrangements, a first fluid to the local inlets of the first plurality of fluid passages, and supplying a second fluid to the local inlets of the second plurality of fluid passages;   b) measuring, by the local sensor arrangement, temperature values corresponding to the local temperatures of the evaporated fluid flowing nearby the local outlets of the first plurality of fluid passages;   c) transmitting the measured temperature values to the controller;   d) determining, by the controller, a difference between the measured temperature values;   e) determining, by the controller, a local adjustment of the local amount of fluid supplied by at least one of the plurality of injector arrangements based on the determined difference, in order to even out the determined difference,   f) communicating, by the controller, with the valves of the plurality of injector arrangements to adjust the local amount of first fluid supplied by at least one of the plurality of injector arrangements according to the determined local adjustment.   
     
     
         12 . The method according to  claim 11 , further comprising:
 determining a compensating local adjustment of the local amount of first fluid supplied by the other than the at least one of the injector arrangements in order to keep the global amount of first fluid in the plurality of first passages unaffected by the local adjustments; and   communicating, by the controller, with the valves of the plurality of injector arrangements to adjust the local amount of first fluid supplied by said other than the at least one of the plurality of injector arrangements according to the determined compensating local adjustment.   
     
     
         13 . The method according to  claim 11 , wherein the determining of the difference comprises determining the standard deviation for the measured temperature values. 
     
     
         14 . The method according to  claim 11 , wherein the system further comprises a global sensor arrangement comprising a global temperature sensor and a global pressure sensor, the method further comprising:
 g) measuring, by the global sensor arrangement, a global temperature value and a global pressure value of the evaporated first fluid downstream from the first global outlet;   h) transmitting the measured global temperature value and measured global pressure value to the controller;   i) determining, by the controller, the superheating value based on the measured global temperature value and the measured global pressure value;   j) determining, by the controller, the difference between the determined superheating value and a set-point superheating value, or the presence of any liquid content in the evaporated first fluid;   k) determining, by the controller, a global adjustment of the amount of first fluid supplied by the plurality of injector arrangements, required to reach the set-point superheating value,   l) communicating, by the controller, with the valves of the plurality of injector arrangements, or with a global valve, to adjust the global amount of first fluid supplied by the plurality of injector arrangements according to the determined global adjustment.   
     
     
         15 . The method according to  claim 14 , wherein the steps b)-f) and the steps g)-l) are performed in parallel. 
     
     
         16 . The method according to  claim 14 , wherein the steps b)-f) and the steps g)-l) are continuously performed as parallel loops in the controller.