Inferential sensor for internal heat exchanger parameters

Abstract

Methods, devices, and systems for an inferential sensor for internal heat exchanger parameters are described herein. One device includes a memory, and a processor configured to execute executable instructions stored in the memory to receive a number of measured process variables of a heat exchanger, including a number of measured inlet process variables and a number of measured outlet process variables, predict, using a dynamic differential model including the number of measured inlet process variables, internal parameters of the heat exchanger and a number of outlet process variables of the heat exchanger, compare the number of measured outlet process variables with the number of predicted outlet process variables, and update, based on the comparison, the internal parameters of the heat exchanger.

What is claimed: 
     
         1 . An inferential sensor for internal heat exchanger parameters, comprising:
 a memory;   a processor configured to execute executable instructions stored in the memory to:
 receive a number of measured process variables of the heat exchanger, including:
 a number of measured inlet process variables; and 
 a number of measured outlet process variables; 
 
 predict, using a dynamic differential model including the number of measured inlet process variables:
 internal parameters of the heat exchanger; and 
 a number of outlet process variables of the heat exchanger; 
 
 compare the number of measured outlet process variables with the number of predicted outlet process variables; and 
 update, based on the comparison, the internal parameters of the heat exchanger. 
   
     
     
         2 . The inferential sensor of  claim 1 , wherein the number of measured inlet process variables include:
 an inlet temperature of the hot fluid of the heat exchanger;   an inlet temperature of the cold fluid of the heat exchanger;   an inlet pressure of the hot fluid of the heat exchanger;   an inlet pressure of the cold fluid of the heat exchanger;   an inlet flow rate of the hot fluid of the heat exchanger; and   an inlet flow rate of the cold fluid of the heat exchanger.   
     
     
         3 . The inferential sensor of  claim 1 , wherein the number of measured outlet process variables include:
 an outlet temperature of the hot fluid of the heat exchanger;   an outlet temperature of the cold fluid of the heat exchanger;   an outlet pressure of the hot fluid of the heat exchanger;   an outlet pressure of the cold fluid of the heat exchanger;   an outlet flow rate of the hot fluid of the heat exchanger; and   an outlet flow rate of the cold fluid of the heat exchanger.   
     
     
         4 . The inferential sensor of  claim 1 , wherein the internal parameters of the heat exchanger include a heat transfer coefficient of the heat exchanger. 
     
     
         5 . The inferential sensor of  claim 1 , wherein the internal parameters of the heat exchanger include metal temperatures of a heat exchange surface of the heat exchanger. 
     
     
         6 . The inferential sensor of  claim 1 , wherein the processor is configured to execute the instructions calculate an efficiency of the heat exchanger using the internal parameters of the heat exchanger and the number of measured process variables of the heat exchanger. 
     
     
         7 . The inferential sensor of  claim 1 , wherein the predicted number of outlet process variables include:
 a predicted outlet temperature of the hot fluid of the heat exchanger;   a predicted outlet temperature of the cold fluid of the heat exchanger;   a predicted outlet pressure of the hot fluid of the heat exchanger;   a predicted outlet pressure of the cold fluid of the heat exchanger;   a predicted outlet flow rate of the hot fluid of the heat exchanger; and   a predicted outlet flow rate of the cold fluid of the heat exchanger.   
     
     
         8 . The inferential sensor of  claim 1 , wherein the dynamic differential model includes a heat and mass balance of the number of measured inlet process variables and the number of measured outlet process variables, wherein the number of measured inlet process variables and the number of measured outlet process variables change with time, and wherein:
 the heat and mass balance determines a metal temperature of the heat exchange surface of the heat exchanger; and   heat transfer from the hot fluid of the heat exchanger to the cold fluid of the heat exchanger is determined by a logarithmic mean temperature between a temperature of the hot fluid, the metal temperature of the heat exchange surface of the heat exchanger, and a temperature of the cold fluid of the heat exchanger.   
     
     
         9 . The inferential sensor of  claim 1 , wherein a nominal heat exchanger has a nominal heat transfer coefficient. 
     
     
         10 . The inferential sensor of  claim 1 , wherein the heat exchanger has a heat transfer coefficient. 
     
     
         11 . The inferential sensor of  claim 1 , wherein the controller is part of a heat pump. 
     
     
         12 . The inferential sensor of  claim 1 , wherein the controller is part of an air-conditioner. 
     
     
         13 . The inferential sensor of  claim 1 , wherein the processor is configured to execute the instructions while the heat exchanger is operating. 
     
     
         14 . A method for an inferential sensor for internal heat exchanger parameters, comprising:
 receiving a number of measured process variables of the heat exchanger, including:
 a number of measured inlet process variables; and 
 a number of measured outlet process variables of the heat exchanger; 
   predicting internal parameters of the heat exchanger and a number of outlet process variables by a dynamic differential model using a heat and mass balance of the number of measured inlet process variables and the number of measured outlet process variables of the heat exchanger;   comparing the number of measured outlet process variables with the number of predicted outlet process variables; and   updating, based on the comparison, the internal parameters of the heat exchanger.   
     
     
         15 . The method of  claim 14 , wherein updating the internal parameters of the heat exchanger include updating a heat transfer coefficient of the heat exchanger. 
     
     
         16 . The method of  claim 14 , wherein updating the internal parameters of the heat exchanger include updating metal temperatures of a heat exchange surface of the heat exchanger. 
     
     
         17 . The method of  claim 14 , wherein the method is continuously repeated. 
     
     
         18 . A system for an inferential sensor for internal heat exchanger parameters, comprising:
 a heat pump;   a heat exchanger;   a controller configured to:
 receive a number of measured process variables of the heat exchanger, including:
 a number of measured inlet process variables of the heat exchanger; 
 a number of measured outlet process variables of the heat exchanger; 
 
 predict, using a dynamic differential model including the number of measured inlet process variables:
 internal parameters of the heat exchanger; and 
 a number of outlet process variables of the heat exchanger; 
 
 compare the number of measured outlet process variables with the number of predicted outlet process variables; 
 update, based on the comparison, the internal parameters of the heat exchanger. 
   
     
     
         19 . The system of  claim 18 , wherein the heat exchanger is a liquid-liquid heat exchanger. 
     
     
         20 . The system of  claim 18 , wherein the heat exchanger is a phase change heat exchanger.