US 11,920,871 B2
Methods and systems for measuring state of charge of a phase change material thermal battery
Nader Maharmeh, Manassas, VA (US); Craig English, Indianapolis, IN (US); Eric Donovan, Fishers, IN (US); Eugene Jansen, Stafford, VA (US); and Ryan Young, Warrenton, VA (US)
Assigned to ROLLS-ROYCE NORTH AMERICAN TECHNOLOGIES INC., Indianapolis, IN (US)
Filed by Rolls-Royce North American Technologies Inc., Indianapolis, IN (US)
Filed on Nov. 25, 2020, as Appl. No. 17/104,339.
Prior Publication US 2022/0163270 A1, May 26, 2022
Int. Cl. F28D 20/02 (2006.01); G01K 17/00 (2006.01)
CPC F28D 20/028 (2013.01) [G01K 17/00 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A method of determining a capacity of a thermal battery, comprising:
transferring heat to and/or from a phase change material in a vessel via a heat exchanger;
detecting an indication of a plurality of temperatures corresponding to a plurality of volumes of the phase change material with a plurality of temperature sensors; and
determining a real-time heat duty of the phase change material from the indication of the temperatures corresponding to the volumes of the phase change material with temperature sensors,
wherein the vessel further comprises a gas that is adjacent to the phase change material, the method further comprising:
detecting an indication of a temperature of the gas with a temperature sensor;
detecting an indication of a pressure of the gas with a pressure sensor; and
determining a state of charge of the phase change material from the indication of the pressure of the gas and the indication of the temperature of the gas, wherein the state of charge of the phase change material is determined from the indication of the pressure of the gas and the indication of the temperature of the gas by determining a total volume of the gas from the indication of the pressure and the indication of the temperature of the gas and determining a total volume of the phase change material by subtracting the total volume of the gas from the volume of the vessel.
 
5. A method of determining a capacity of a thermal battery, comprising:
transferring heat to and/or from a phase change material in a vessel via a heat exchanger;
detecting an indication of a plurality of temperatures corresponding to a plurality of volumes of the phase change material with a plurality of temperature sensors;
determining a real-time heat duty of the phase change material from the indication of the temperatures corresponding to the volumes of the phase change material with temperature sensors and by determining a real-time heat duty for each of the volumes of the phase change material based on a heat transfer area and thermal resistance at locations in the heat exchanger associated with the volumes and by summing the real-time heat duty for each of volumes.
 
6. A method of determining a capacity of a thermal battery, comprising:
transferring heat to and/or from a phase change material in a vessel via a heat exchanger;
detecting an indication of a plurality of temperatures corresponding to a plurality of volumes of the phase change material with a plurality of temperature sensors, wherein the volumes are arranged in a matrix within the vessel; and
determining a real-time heat duty of the phase change material from the indication of the temperatures corresponding to the volumes of the phase change material with temperature sensors and by determining a real-time heat duty for each of the volumes of the phase change material based on a heat transfer area and thermal resistance at locations in the heat exchanger associated with the volumes and by summing the real-time heat duty for each of volumes.