cooling air/ flow rate summary

T. Pratum (pratum@u.washington.edu)
Wed, 12 Nov 1997 16:00:13 -0800 (PST)

Thanks to all who responded to my query about cooling air flow rates and
spectrometer instability. The solutions I think fall into 2 categories:
1) use colder cooling air, either by using a colder source (such as LN2)
or by using better transfer line material so the air doesn't warm up so
much on the way to the probe. With cooler air the flow rate can obviously
be turned down.
2) weight the spinner down by adding weights to it (lead shot, wound
solder, etc), use a ceramic spinner, or even put 2 spinners on the tube to
weight it down more. A heavier spinner is much less likely to bounce up
and down.
It was also pointed out that the users will probably have to recalibrate
the temperature curve for the probe if they run at higher flow rate.


Tom Pratum
Dept of Chemistry
Box 351700
Univ of Washington
pratum@u.washington.edu
http://weber.u.washington.edu/~pratum