Attendants: B. Ogert, A. Lee, D. Reitzner, K. Vaziri, J. Fulgham, R.
Reilly, D. Newhart, F.G. Garcia
Date/Hr: 11/09/2010 1:00pm
1) Lee's Heat and Stress Calculations
2) Empirical experience with graphite under vacuum
Meeting started with Lee's presenting heating/stress calculations for
a) Copper (Cu) & SS sleeve
b) Graphite (C) & SS sleeve
c) Tungsten (W) block
d) Graphite core & Tungsten sleeve
His whole presentation can be seen here
The calculations show that either W block and C core + W sleeve should
work for both scenarios: Operational + Accidental.
The W block seems to be the simplest configuration and the
recommended length is 24 cm.
However, the W + C core has the lowest temperature rise due to C core.
Kamran pointed out the possibility of having a higher residual dose rate
in the enclosure due to W usage. W has the potential to create longer
live isotopes than graphite.
On the other hand, graphite presents problem with oxidation, for
instance. Kamran recommended that if this option is chosen, that the
sleeve be made with a container surrounding the graphite. During the
manufacture process, the graphite should be packed while purging inert
gas, such as argon, to significantly reduce the Oxygen content. This
raised another concern, when Rob Reilly pointed out that if the graphite
in inserted in this container, the rise in temperature by beam hitting
the core would increase the pressure inside this volume.
1) Rob Reilly will investigate the mechanical aspect of using W. Explore
the options in creating a flange with SS & W transition in order to
explore the W block option.
Depending on how successful this process it, he will inform Diane who
will run MARS with this configuration and present the residual dose,
stars distribution with beam and W.
Next meeting: 11/30/2010, 1:00 pm. Bungalow.
PS. Please send any correction for this minutes to me.