Method and device for determining the filling mass of a cryogenically stored gas in a container

Patent metadata

Field	Value
Publication number	US-10078000-B2
Application number	US-201514834706-A
Country	US
Kind code	B2
Filing date	Aug 25, 2015
Priority date	Feb 26, 2013
Publication date	Sep 18, 2018
Grant date	Sep 18, 2018

Abstract

A method for determining a filling mass in a thermally insulated container for a cryogenically stored gas includes determining the filling mass using a known container volume and a calculated density of the gas content of the container. A temperature sensor is used for measuring a mixing temperature of liquid and gaseous phases, where the liquid phase is extracted via a first extraction supply line at the geodetically lowest point, and the gaseous phase is extracted via a second extraction supply line at the geodetically highest point. Downstream of the extraction points, after a convergence of the first and the second extraction supply line, the temperature sensor is placed where a complete and thorough mixing of the liquid and the gaseous phase of the gas from the first and second extraction supply line has already taken place.

First claim

What is claimed is:

1. A method for determining a filling mass in a thermally insulated container for a cryogenically stored gas, comprising the acts of:
determining the filling mass using a known container volume and a calculated density of the cryogenically stored gas in the container, wherein the calculated density is calculated from a container pressure measurement and a temperature measurement; and
measuring, by a temperature sensor, a mixing temperature of a liquid phase and a gaseous phase of the cryogenically stored gas, wherein the liquid phase is extracted by way of a first extraction supply line at a geodetically lowest point and the gaseous phase is extracted by way of a second extraction supply line at a geodetically highest point of a cavity of the container,
wherein the temperature sensor is placed downstream of the geodetically lowest and highest points, after a convergence of the first and second extraction supply lines to a single extraction line leading out of the container, on an inside or outside of said single extraction line, at a location where complete and thorough mixing of the liquid phase and the gaseous phase of the cryogenically stored gas from the first and second extraction supply lines has already taken place.

2. The method as claimed in claim 1 , wherein at least one of stored calibration values, stored correction values, stored calibration functions and stored correction functions are used for making allowance at least for the position of the temperature sensor in the determination of the filling mass.

3. The method as claimed in claim 1 , wherein the filling mass of the container is determined as and when desired or automatically repeatedly at time intervals.

4. A device for determining the filling mass in a thermally insulated container which contains a medium that is, in one part, in the liquid phase and, in another part, in the gaseous phase, wherein the container comprises a pressure gage and a temperature sensor that measures a mixing temperature of the liquid phase and the gaseous phase of the cryogenically stored gas,
wherein the device is configured to extract the liquid phase by way of a first extraction supply line at a geodetically lowest point and to extract the gaseous phase by way of a second extraction supply line at a geodetically highest point of a cavity of the container,
wherein the temperature sensor is placed downstream of the geodetically lowest and highest points, after a convergence of the first and second extraction supply lines to a single extraction line leading out of the container, on an inside or outside of said single extraction line, at a location where complete and thorough mixing of the liquid phase and the gaseous phase of the cryogenically stored gas from the first and second extraction supply lines has already taken place.

5. The device as claimed in claim 4 , wherein at least one of a point of the convergence of the two extraction supply lines and the single extraction line is configured such that complete and thorough mixing of the liquid phase and the gaseous phase of the cryogenically stored gas from the first and second extraction supply lines takes place.

6. The device as claimed in either of claim 5 , wherein the temperature sensor is located outside the container.

7. The device as claimed in either of claim 4 , wherein the temperature sensor is located outside the container.

8. The device as claimed in either of claim 4 , further comprising a control device with a computing device configured to determine the filling mass of the container as and when desired or automatically repeatedly at time intervals.

9. The device as claimed in claim 8 , wherein at least one of stored calibration values, stored correction values, stored calibration functions and stored correction functions are used for making allowance at least for the position of the temperature sensor in the determination of the filling mass.

10. A container with a device as claimed in claim 4 , wherein said container is used as a store for receiving the cryogenic gas as an operating medium of a drive unit of a motor vehicle and is held in a thermally insulated manner in an outer container that is accommodated in the motor vehicle, wherein the motor vehicle has, in an interior, an indicating device that presents to a driver of the motor vehicle a last-calculated filling mass, at least in comparison with a maximum filling mass and a minimum filling mass.

Assignees

• Bayerische Motoren Werke Ag

Inventors

• Kampitsch Markus
• Schott Stefan

Classifications

• F17C2260/022

  Avoiding overfilling · CPC title

• F17C2250/0439

  Temperature · CPC title

• F17C2250/043

  Pressure · CPC title

• F17C13/026

  having the temperature as the parameter · CPC title

• G01F23/22 Primary

  by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water (involving the use of floats G01F23/30) · CPC title