Method and system for detecting a component in a fluid

Patent metadata

Field	Value
Publication number	US-9739706-B2
Application number	US-201414467136-A
Country	US
Kind code	B2
Filing date	Aug 25, 2014
Priority date	Aug 29, 2013
Publication date	Aug 22, 2017
Grant date	Aug 22, 2017

Abstract

A method for detecting of components in a fluid includes emitting a modulated light beam from a modulated light source to the fluid in a chamber, wherein the fluid comprises a liquid and a component in the liquid. The method includes producing an acoustic signal in response to the emitted modulated light beam and detecting the acoustic signal via a pressure sensor disposed in the chamber. The method in one example also includes transmitting the acoustic signal from the pressure sensor to a processor based module and determining at least one of a component and a concentration of the component in the fluid via the processor based module, based on the acoustic signal.

First claim

What is claimed is:

1. A system, comprising:
a chamber having a fluid including a liquid and a component in the fluid;
a modulated light source for emitting an amplitude modulated light beam;
a first beam wavelength and a second beam wavelength selected from the amplitude modulated light beam wherein the first beam wavelength and the second beam wavelength are generated alternatively;
the component absorbs a first amount of light energy when the first beam wavelength is transmitted to the fluid and a second amount of light energy different from the first amount of energy when the second beam wavelength is transmitted to the fluid, and producing acoustic signals from the component;
a pressure sensor disposed proximate the chamber, for detecting the acoustic signals; and
a processor based module communicatively coupled to the pressure sensor and configured to receive the acoustic signals from the pressure sensor and determine at least one of the component and a concentration of the component in the fluid based on a difference in the acoustic signals.

2. The system of claim 1 , wherein the component is a gaseous component.

3. The system of claim 2 , wherein the gaseous component comprises acetylene, hydrogen, methane, ethane, ethylene, carbon dioxide, moisture, carbon monoxide, and combinations thereof.

4. The system of claim 1 , wherein the modulated light source comprises a laser source and a modulator device.

5. The system of claim 4 , wherein the modulator device receives a light beam from the laser source, and modulates the light beam.

6. The system of claim 1 , wherein one of the first beam wavelength and the second beam wavelength has a first absorption value within a first range of absorption values in an absorption spectra of the component.

7. The system of claim 6 , wherein another among the first beam wavelength and the second beam wavelength has a second absorption value within a second range of absorption values in the absorption spectra of the component, wherein the second range of absorption values is different from the first range of absorption values.

8. The system of claim 1 , wherein both the first beam wavelength and the second beam wavelength have a plurality of absorption values within a range of absorption values in an absorption spectra of the liquid.

9. The system of claim 1 , wherein the pressure sensor is at least one of a piezo effect based sensor, a cantilever based sensor, a microphone, a hydrophone, a capacitance based sensor, and a membrane based sensor.

10. The system of claim 1 , wherein the modulated light source comprises a light source, at least one filter, and a modulator device for controlling at least one of an intensity of a light beam generated from the light source, a wavelength of the light beam, and a parameter of the light source.

11. A method, comprising:
emitting an amplitude modulated light beam to a fluid in a chamber wherein the fluid comprises a liquid and a component in the liquid;
selecting a first beam wavelength and a second beam wavelength from the amplitude modulated light beam and generating the first beam wavelength and the second beam wavelength alternatively, wherein the component absorbs a first amount of light energy when the first beam wavelength is transmitted to the fluid and a second amount of light energy different from the first amount of energy when the second beam wavelength is transmitted to the fluid, and producing acoustic signals from the component;
producing acoustic signals from the component in response to the first beam wavelength and the second beam wavelength;
detecting the acoustic signals via a pressure sensor disposed in the chamber;
transmitting the acoustic signals from the pressure sensor to a processor based module;
and determining at least one of the component and a concentration of the component in the fluid via the processor based module, from a difference in the acoustic signals.

12. The method of claim 11 , further comprising generating the first beam wavelength and the second beam wavelength from the amplitude modulated light beam via at least one optical filter.

13. The method of claim 11 , wherein the producing comprises generating the acoustic signal from the component due to a difference between a first absorption value within a first range of absorption values and a second absorption value within a second range of absorption values in an absorption spectra of the component.

14. The method of claim 11 , wherein the emitting comprises modulating an amplitude of a light beam via a modulator device.

15. The method of claim 11 , wherein the emitting comprises modulating a laser beam by varying a power applied to a laser source or an ambient temperature of the laser source.

16. The method of claim 11 , wherein the determining comprises one of the followings:
measuring an amplitude of the acoustic signal;
measuring the concentration of the component based on the measured amplitude;
measuring the amplitude of the acoustic signal using a synchronous demodulation technique; and
identifying the component based on a range of wavelength of the modulated light beam.

Assignees

• Gen Electric

Inventors

• Maity Sandip
• Sethumadhavan Nagapriya Kavoori
• Choudhury Niloy

Classifications

• G01N2291/02809

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

• G01N2291/02433

  Gases in liquids, e.g. bubbles, foams · CPC title

• G01N2021/1708

  with piezotransducers · CPC title

• G01N29/48

  by amplitude comparison · CPC title

• G01N29/46

  by spectral analysis, e.g. Fourier analysis {or wavelet analysis (spectral signal processing per se G06F17/14)} · CPC title