Impaction densitometer

Patent metadata

Field	Value
Publication number	US-9377389-B2
Application number	US-201414186057-A
Country	US
Kind code	B2
Filing date	Feb 21, 2014
Priority date	Feb 25, 2013
Publication date	Jun 28, 2016
Grant date	Jun 28, 2016

Abstract

Disclosed is an impaction densitometer having a chamber configured to receive a particle; a beam generator configured to emit a beam; a detector configured to receive the beam and convert a change in intensity of the received beam into an electrical signal corresponding to a particle volume; an impact sensor positioned a known distance from the beam and configured to measure a particle momentum as a function of an impact energy transferred from the particle to the impact sensor; a velocity calculator configured to calculate a particle velocity based on a time it takes the particle to pass through the beam and strike the impact sensor; a mass calculator configured to calculate a particle mass as a function of the particle momentum and velocity; and a density calculator configured to calculate a particle density as a function of the particle mass and volume.

First claim

What is claimed is:

1. An impaction densitometer, comprising:
a chamber configured to receive a particle;
a beam generator configured to emit a beam crossing a particle direction of travel within the chamber;
a detector configured to receive the beam and convert a change in intensity of the received beam, resulting from the particle passing through the beam, into an electrical signal corresponding to a particle volume;
an impact sensor positioned a known distance from the beam and configured to measure a particle momentum as a function of an impact energy transferred from the particle to the impact sensor;
a velocity calculator configured to calculate a particle velocity based on a time it takes the particle to pass through the beam and strike the impact sensor;
a mass calculator configured to calculate a particle mass as a function of the particle momentum and velocity; and
a density calculator configured to calculate a particle density as a function of the particle mass and volume.

2. The impaction densitometer of claim 1 , further comprising an adjustable vacuum generator connecting with the chamber.

3. The impaction densitometer of claim 1 , further comprising an adjustable feeder configured to feed the particle into the chamber.

4. The impaction densitometer of claim 3 , further comprising an injection needle connecting the adjustable feeder to the chamber.

5. The impaction densitometer of claim 1 , further comprising a beam spreader configured to spread the beam into a sheet.

6. The impaction densitometer of claim 5 , wherein the beam spreader is selected from the group consisting of at least one lens, at least one slit, at least one mirror, and at least one prism.

7. The impaction densitometer of claim 1 , wherein the beam generator is further configured to emit the beam perpendicular to the particle travel direction.

8. The impaction densitometer of claim 1 , wherein the detector includes a photodiode configured to produce a signal attenuation curve containing data on particle diameter and shape.

9. The impaction densitometer of claim 1 , wherein the impact sensor is a microphone.

10. The impaction densitometer of claim 1 , wherein the impact sensor is configured to produce an impact signal proportion to an impact energy generated by the particle striking the impact sensor.

11. The impaction densitometer of claim 1 , further comprising a data acquisition module configured to acquire particle data upon detection of the change in beam intensity.

12. A method of particle measurement, comprising the steps of:
passing a particle through a beam;
measuring a change in intensity of the beam resulting from the particle passing through the beam;
calculating a particle volume based on the change in beam intensity;
impacting the particle at a known distance from the beam;
measuring an impact energy of the particle;
calculating a particle momentum as a function of the particle impact energy;
calculating a particle velocity as a function of a time it takes the particle to impact after travelling the known distance from the beam;
calculating a particle mass as a function of the particle momentum and velocity; and
calculating a particle density as a function of the particle mass and volume.

13. The method of claim 12 , further comprising the step of creating an adjustable vacuum within the chamber.

14. The method of claim 12 , further comprising the step of feeding multiple particles into the chamber.

15. The method of claim 14 , further comprising the step of calculating at least 10 particle densities per second.

16. The method of claim 15 , further comprising the step of preparing a histogram of at least one of a plurality of particle densities and a plurality of particle sizes.

17. The method of claim 12 , further comprising the step of orienting the beam perpendicular to the particle travel direction.

18. The method of claim 12 , further comprising the step of spreading the beam into a sheet.

19. The method of claim 12 , further comprising the step of producing a signal attenuation curve containing data on particle diameter and shape.

20. A computer program product comprising a non-transitory computer readable medium having stored thereon computer executable instructions that when executed causes the following steps to be performed, the steps comprising:
passing a particle through a beam;
measuring a change in intensity of the beam resulting from the particle passing through the beam;
calculating a particle volume based on the change in beam intensity;
impacting the particle at a known distance from the beam;
measuring an impact energy of the particle;
calculating a particle momentum as a function of the particle impact energy;
calculating a particle velocity as a function of a time it takes the particle to impact after passing through the known distance from the beam;
calculating a particle mass as a function of the particle momentum and velocity; and
calculating a particle density as a function of the particle mass and volume.

Assignees

• Us Energy
• Us Dept Energy

Inventors

• Parrington Josef R

Classifications

• G01N9/00

  Investigating density or specific gravity of materials; Analysing materials by determining density or specific gravity · CPC title

• G01N9/02

  by measuring weight of a known volume · CPC title

• G01N15/1463 Primary

  Physics · mapped topic

• G01N2015/1493

  Particle size · CPC title

• G01N15/10 Primary

  Investigating individual particles · CPC title