Claims
- 1. A method, comprising:
directing a gas flow into a gas flow channel from an input opening to an output opening; vaporizing a liquid to produce a vapor from the liquid to fill the gas flow channel; producing a spatial temperature distribution in the gas flow channel that changes with position from the input opening to the output opening, and that includes a plurality of alternating hot and cold regions arranged next to one another where a hot region has a temperature higher than an adjacent cold region; selecting temperatures of the hot and cold regions to spatially increase a temperature difference between adjacent hot and cold segments from the input opening to the output opening in the gas flow channel; and determining presence and dimension of particles in the gas flow which are condensed with the vapor.
- 2. The method as in claim 1, wherein the hot regions in the gas flow channel are maintained at a constant elevated temperature and the cold regions are maintained at different temperatures which monotonically decrease from the input opening to the output opening and are lower than the elevated temperature.
- 3. The method as in claim 1, wherein the cold regions are maintained at a constant low temperature and the hot regions are maintained at different temperatures which increase with position from the input opening to the output opening and are higher than the low temperature.
- 4. The method as in claim 1, wherein a pressure of the gas flow channel is not a constant, and further comprising:
calibrating the determination of the presence and dimension of particles in the gas flow to account for the pressure variation.
- 5. The method as in claim 1, wherein the presence and dimension of particles in the gas flow are measured optically by illuminating an optical beam to the gas flow at the output opening, without introducing another flow into the gas flow.
Parent Case Info
[0001] This application claims the benefit of the U.S. Provisional application Ser. No. 60/062,013, filed on Oct. 10, 1997, which is incorporated herein by reference.
ORIGIN OF THE INVENTION
[0002] The U.S. Government has certain rights in this invention pursuant to Grant No. N00014-96-1-0119 awarded by the Navy.
Provisional Applications (1)
|
Number |
Date |
Country |
|
60062013 |
Oct 1997 |
US |
Continuations (1)
|
Number |
Date |
Country |
Parent |
09169274 |
Oct 1998 |
US |
Child |
09990599 |
Nov 2001 |
US |