Acousto-microwave system for determining mass or leak of gas in a vessel and process for same

Patent metadata

Field	Value
Publication number	US-10036683-B2
Application number	US-201615188211-A
Country	US
Kind code	B2
Filing date	Jun 21, 2016
Priority date	Jun 22, 2015
Publication date	Jul 31, 2018
Grant date	Jul 31, 2018

Abstract

An acousto-microwave system to determine a mass M of gas disposed in a vessel includes: a microwave transmitter disposed on the vessel to transmit microwave radiation inside the vessel, a portion of the microwave radiation occurring at a microwave resonance of the vessel; a microwave receiver disposed on the vessel to receive microwave radiation communicated through an interior of the vessel from the microwave transmitter; an acoustic transmitter disposed on the vessel to transmit acoustic radiation inside the vessel, a portion of the acoustic radiation occurring at an acoustic resonance of the gas in the vessel; and an acoustic receiver disposed on the vessel to receive acoustic radiation communicated through the gas from the acoustic transmitter. The mass M of the gas is determined by analyzing the microwave radiation received by the microwave receiver and the acoustic radiation received by the acoustic receiver.

First claim

What is claimed is:

1. An acousto-microwave system to determine a mass M of gas disposed in a vessel, the acousto-microwave system comprising:
a microwave transmitter disposed on the vessel to transmit microwave radiation inside the vessel, a portion of the microwave radiation occurring at a microwave resonance of the vessel;
a microwave receiver disposed on the vessel to receive microwave radiation communicated through an interior of the vessel from the microwave transmitter;
an acoustic transmitter disposed on the vessel to transmit acoustic radiation inside the vessel, a portion of the acoustic radiation occurring at an acoustic resonance of the gas in the vessel; and
an acoustic receiver disposed on the vessel to receive acoustic radiation communicated through the gas from the acoustic transmitter;
a pressure meter to provide a pressure of the gas in the vessel;
a microwave source in electrical communication with the microwave transmitter, the microwave source to provide the microwave radiation to the microwave transmitter prior to the transmission of the microwave radiation inside the vessel;
an acoustic driver in electrical communication with the acoustic transmitter, the acoustic driver to control the acoustic transmitter for production of the acoustic radiation by the acoustic transmitter in response to an acoustic control signal provided to the acoustic transmitter from the acoustic driver; and
a processor to receive microwave data from the microwave receiver, acoustic data from the acoustic receiver, temperature data from the pressure meter, the processor to determine the mass M of the gas disposed in the vessel based on the microwave data, acoustic data, and temperature data.

2. The acousto-microwave system of claim 1 , wherein the processor determines a volume of the vessel from the microwave data, and
determines a speed of sound in the gas from the acoustic data.

3. The acousto-microwave system of claim 2 , wherein the mass M of the gas is determined by the processor according to

M
=

ρ
⁡

(

p
,
u

)

⁢
V

≈

γ
0

⁢
pV

u
2

[

1
+

(

β
α

-
B

)

⁢

p
RT

⁢

]

,

wherein M is the mass of the gas; ρ is the density of the gas; γ 0 is a zero-pressure heat-capacity ratio that is equal to C p /C v , wherein C p is a constant pressure heat capacity of the gas, and C v is the constant volume heat capacity of the gas; p is the pressure of the gas; V is the volume of the vessel; u is the speed of sound in the gas; β α is an acoustic virial coefficient; B is a density virial coefficient; R is an ideal gas constant; and T is an average temperature of the gas in the vessel.

4. A process for determining a mass M of a gas disposed in a vessel, the process comprising:
subjecting an interior of the vessel with microwave radiation transmitted by a microwave transmitter disposed on the vessel, a portion of the microwave radiation occurring at a microwave resonance of the vessel;
communicating the microwave radiation through an interior of the vessel;
receiving, by a microwave receiver disposed on the vessel, the microwave radiation communicated through the interior of the vessel;
transmitting, by an acoustic transmitter disposed on the vessel, acoustic radiation;
subjecting the gas disposed in the vessel with the acoustic radiation transmitted by the acoustic transmitter, a portion of the acoustic radiation occurring at an acoustic resonance of the gas in the vessel;
communicating the acoustic radiation through the gas disposed in the vessel;
receiving, by an acoustic receiver disposed on the vessel, the acoustic radiation communicated through the gas disposed in the vessel; and
analyzing the microwave radiation received by the microwave receiver and the acoustic radiation received by the acoustic receiver to determine the mass M of the gas disposed in the vessel.

5. The process of claim 4 , further comprising determining a pressure of the gas disposed in the vessel.

6. The process of claim 5 , wherein determining the pressure of the gas disposed in the vessel comprises acquiring a pressure signal from a pressure meter disposed on the vessel.

7. The process of claim 6 , wherein analyzing the microwave radiation comprises:
determining a microwave frequency of a microwave resonance of the vessel based on the microwave radiation received by the microwave receiver;
determining an acoustic frequency of an acoustic resonance of the gas based on the acoustic radiation received by the acoustic receiver; and
combining the pressure of the gas, the microwave frequency of the microwave resonance of the vessel, and the acoustic frequency of the acoustic resonance of the gas to determine the mass of the gas disposed in the vessel.

8. The process of claim 7 , further comprising determining a volume of the vessel from the microwave frequency of the microwave resonance of the vessel.

9. The process of claim 8 , wherein determining the volume of the vessel comprises:
providing a model shape of the vessel;
providing a plurality of model geometric parameters of the vessel;
computing a model microwave resonance of the vessel based on the model shape and the model geometric parameters;
fitting the microwave resonance and the model microwave resonance;
adjusting the model geometric parameters to obtain a best fit of the microwave resonance and the model microwave resonance; and
determining the volume of the vessel from the geometric parameters used to obtain the best fit.

10. The process of claim 9 , further comprising determining an average temperature of the gas in the vessel from the acoustic frequency of the acoustic resonance of the gas in the vessel.

11. The process of claim 10 , wherein determining the average temperature of the gas comprises determining a speed of sound in the gas from the acoustic frequency of the acoustic resonance of the gas in the vessel.

12. The process of claim 11 , further comprising determining a

Assignees

• Us Commerce
• The Government Of The Us Secretary Of Commerce

Inventors

• Moldover Michael R
• Gillis Keith A
• Mehl James B

Classifications

• G01M3/24 Primary

  using infrasonic, sonic or ultrasonic vibrations · CPC title

• G01N29/036

  by measuring frequency or resonance of acoustic waves · CPC title

• G01N2291/02881

  Temperature · CPC title

• G01N2291/014

  Resonance or resonant frequency · CPC title

• G01N2291/02809

  Concentration of a compound, e.g. measured by a surface mass change · CPC title