Transport refrigeration system with air temperature control

Abstract

A method for air temperature control within a cargo compartment of a transport unit using a transport refrigeration system (TRS) that includes a thermal accumulator having a phase change material (PCM) provided therein is provided. The thermal accumulator is disposed in a thermal accumulator compartment and the cargo compartment is separated from the thermal accumulator compartment via a climate controlled barrier. The method includes a controller receiving, via one or more temperature sensors, temperature data within a cargo compartment of the transport unit from. The method also includes determining a temperature within the cargo compartment based on the temperature data. Also, the method includes determining a temperature stratification within the cargo compartment based on the temperature data. Further, the method includes operating the TRS in an active operation mode when the temperature within the cargo compartment is greater than a temperature set point.

1 . A method for air temperature control within a cargo compartment of a transport unit using a transport refrigeration system (TRS) that includes a thermal accumulator having a phase change material (PCM) provided therein, the thermal accumulator being disposed in a thermal accumulator compartment, and the cargo compartment being separated from the thermal accumulator compartment via a climate controlled barrier, the method comprising:
 a controller receiving, via one or more temperature sensors, temperature data within a cargo compartment of the transport unit from;   determining a temperature within the cargo compartment based on the temperature data;   determining a temperature stratification within the cargo compartment based on the temperature data;   operating the TRS in an active operation mode when the temperature within the cargo compartment is greater than a temperature set point.   
     
     
         2 . The method according to  claim 1 , wherein operating the TRS in the active operation mode includes:
 opening one or more adjustable dampers disposed at one or more openings of the climate controlled barrier to an open position; and   directing air from the thermal accumulator compartment through the one or more openings of the climate controlled barrier into the cargo compartment.   
     
     
         3 . The method according to  claim 1 , wherein operating the TRS in the active operation mode includes:
 operating one or more fans adjacent to one or more openings of the climate controlled barrier; and   directing air, via the one or more fans, from the thermal accumulator compartment through the one or more openings of the climate controlled barrier into the cargo compartment.   
     
     
         4 . The method according to  claim 1 , further comprising:
 operating the TRS in a temperature unification mode when the temperature stratification is outside of a stratification threshold range and the temperature within the cargo compartment is less than or equal to the temperature set point.   
     
     
         5 . The method according to  claim 4 , wherein operating the TRS in the temperature unification mode includes:
 closing one or more adjustable dampers disposed at one or more openings of the climate controlled barrier to a closed position; and   distributing air within the cargo compartment to reduce temperature stratification within the cargo compartment.   
     
     
         6 . The method according to  claim 4 , wherein operating the TRS in the temperature unification mode includes:
 operating one or more fans within the cargo compartment; and   distributing air, via the one or more fans, within the cargo compartment to reduce temperature stratification within the cargo compartment.   
     
     
         7 . The method according to  claim 1 , further comprising:
 operating the TRS in a standby operation mode when the temperature stratification is within the stratification threshold range and the temperature within the cargo compartment is less than or equal to the temperature set point.   
     
     
         8 . The method according to  claim 7 , wherein operating the TRS in the standby operation mode includes:
 closing one or more adjustable dampers disposed at one or more openings of the climate controlled barrier to a closed position.   
     
     
         9 . The method according to  claim 7 , wherein operating the TRS in the standby operation mode includes:
 stopping operation of one or more fans within the cargo compartment.   
     
     
         10 . A refrigerated transport unit comprising:
 a transport unit including:
 a cargo compartment for storing cargo, and 
 a climate controlled barrier separating the cargo compartment from a thermal accumulator compartment, the climate controlled barrier including one or more openings configured to provide air flow communication between the cargo compartment and the thermal accumulator compartment; and 
   a transport refrigeration system (TRS) configured to provide air temperature control within the cargo compartment, the TRS including:
 the thermal accumulator compartment including a thermal accumulator, the thermal accumulator having a phase change material (PCM) disposed therein, and 
 a controller configured to control air flow communication between the thermal accumulator compartment and the cargo compartment so as to provide air temperature control within the cargo compartment. 
   
     
     
         11 . The refrigerated transport unit of  claim 10 , further comprising one or more adjustable dampers disposed on the climate controlled barrier, wherein the dampers are configured to control an amount of air flow through the one or more openings between the cargo compartment and the thermal accumulator compartment,
 wherein the controller is configured to control an opening position of the one or more adjustable dampers to control the amount of air flow through the one or more openings between the cargo compartment and the thermal accumulator compartment to control a temperature within the cargo compartment.   
     
     
         12 . The refrigerated transport unit of  claim 10 , further comprising one or more fans configured to at least one of:
 direct air from the thermal accumulator module to the cargo compartment via the one or more openings to control a temperature within the cargo compartment, and   distribute air within the cargo compartment to reduce temperature stratification within the cargo compartment.   
     
     
         13 . The refrigerated transport unit of  claim 12 , wherein the one or more fans is a variable speed fan, and the controller is configured to control a speed of the variable speed fan. 
     
     
         14 . The refrigerated transport unit of  claim 10 , further comprising one or more sensors configured to provide temperature measurements at one or more locations within the cargo compartment. 
     
     
         15 . The refrigerated transport unit of  claim 10 , wherein the thermal accumulator compartment is disposed within the transport unit. 
     
     
         16 . The refrigerated transport unit of  claim 10 , wherein the thermal accumulator compartment is attached to a side wall of the transport unit. 
     
     
         17 . The refrigerated transport unit of  claim 10 , wherein, when a temperature within the cargo compartment is greater than a temperature set point, the controller is configured to:
 open one or more adjustable dampers disposed at the one or more openings of the climate controlled barrier to an open position to direct air from the thermal accumulator compartment through the one or more openings of the climate controlled barrier into the cargo compartment.   
     
     
         18 . The refrigerated transport unit of  claim 10 , wherein, when a temperature within the cargo compartment is greater than a temperature set point, the controller is configured to:
 operate one or more fans adjacent to the one or more openings of the climate controlled barrier to direct air from the thermal accumulator compartment through the one or more openings of the climate controlled barrier into the cargo compartment.   
     
     
         19 . The refrigerated transport unit of any of  claim 10 , wherein, when a temperature stratification is outside of a stratification threshold range and a temperature within the cargo compartment is less than or equal to a temperature set point, the controller is configured to:
 close one or more adjustable dampers disposed at the one or more openings of the climate controlled barrier to a closed position to reduce temperature stratification within the cargo compartment.   
     
     
         20 . The refrigerated transport unit of  claim 10 , wherein, when a temperature stratification is outside of a stratification threshold range and a temperature within the cargo compartment is less than or equal to a temperature set point, the controller is configured to:
 operate one or more fans to distribute air within the cargo compartment to reduce temperature stratification within the cargo compartment.   
     
     
         21 . The refrigerated transport unit of  claim 10 , wherein, when a temperature stratification is within a stratification threshold range and a temperature within the cargo compartment is less than or equal to a temperature set point, the controller is configured to:
 close one or more adjustable dampers disposed at one or more openings of the climate controlled barrier to a closed position.   
     
     
         22 . The refrigerated transport unit of  claim 10 , wherein, when a temperature stratification is within a stratification threshold range and a temperature within the cargo compartment is less than or equal to a temperature set point, the controller is configured to:
 stop operation of one or more fans within the cargo compartment.