Physics and engineering aspects of the Oak Ridge experimental power reactor Page: 4 of 5

I'ntctiOn of r.di il di..tance from the plasma center is
shown in Figure I..

Figure 5
Note that the abscissa is offset by 200 cm. The solid
curve shows the radial dependence of the heating due
to neutrons and geaa rays and the curve bearing the
tick marks shows the radial dependence of the heating
from neutrons only. The heat deposition occurs pre-
dominantly in the blanket followed by a somewhat
rapid reduction in the heating through the shield.
The effectiveness of the iron and the lead layers
in the shield in attenuating gamrea rays generated
in both the blanket and the shield and converting
them to heat in the shield rather than in the
cryogenic TF coil is shown clearly in the large
differences between the two cunes for these
materials. The structure in the two curves in the
iTF coil region shows the contributions to local
heating free the copper coil windings and their iron
enclosures.
The total fraction of energy deposited in the
blanket assembly is F9.81, which is consistent with
the design specification for 90% energy deposition
in the blanket. 'he graphite curtain and the shield
absorb 10.1% of the total heat, and the remainder
(<< 0.1%) is absorbed in the TI coil assembly.
Estimates of the radiation damage in the first
iron wall and in the first copper winding in the TF
coil are given ir. Table IV.

Table IV
Estimates of Radiation Damage

Hydro en Atoms Helium Atoms
dpa/year cm year cm3 year

1.89

First Iron Wall
4.73 x 10"
(56 appo)

1.47 x 10 t
(18 appm)

4.20 x 10-

First Copper Winding
in 'F Coil
3.75 x 1D12

8.71 x 10'

--------
I '--
6T-- --'-J
- _
- -LL-LLI

4

- -'
- ! I

'these results are continuous operation for one year at
a source neutron wall loading of 0.168 MW/rat. The
displacement cross sections used in arriving at these
values have thresholds of 40 eV for iron and 30 eV for
copper. At the assumed power level, the atomic-
displacement rate and the gas-production rate are low
and do not represent a significant level of damage to
either the first iron wall and, most certainly, to
the copper windings in the TF coil.
If these data are extrapolated to a wall loading
of 1.0 MW/m2, the atomic-displacement rate is 11.25
dpa/y, a value that is consistent with the rates
predicted by Kulciuski, Doran, and Abdou1 and by
Williams, Santoro, and Gabriel.'2 It should be noted
that in both References 11 and 12 stainless-steel alloys
rather than just iron were used in calculating the dpa
rates. Correspondingly, the hydrogen- and helium-
production rates in the first iron wall increase to
2.82 x 1019 hydrogen and 8.80 x 101" helium atoms per
year, respectively. These values correspond to 334
and 104 appm per year, respectively, and are consis-
tent with values obtained by Abdou and Conn5' in their
comparison of radiation damage in several first-wail
materials. At the higher wall loading, the dpa and
gas-production rates are still low in the TF-coil
windings.
Conclusions
The energy production and conversion systems
aspects of the ORSL-EPR described in the text were
developed from a broad scoping study performed pre-
viously. Detailed physics and engineering dcsi:n :ie
ahead. The effort thus far his been to locate the liFf
in a very complex multi-dimensional parameter sp2cc.
This task is complete. The EPR as described will be
capable of producing several hundred thermal t.cpawatts.
With scaling; marginally it proved beyond that prese :tly
predicted, a demonstration of breakeven will be
achieved. The blanket, shield and cooling systes are
sufficient to nake the heat available at a hitl temper-
ature datum and to shield the cryogenic systems 11e
excessive inputs as well as provide suitable biological
protection.
Acknowledgements
The authors express their gratitude to all the
EPR design team participants. In particular, M.
Roberts has continuously encouraged the work. Dis-
cussions with R. G. Alsmiller (Neutron Physics) :.nd
J. D. Callen (Thermonuclear Division) were Host
helpful.
References
1. N. A. Uckan, K. T. Tsang, .1. D. Callen, "Toreida
Field Ripple Criteria for Large Tokamaks," paper
#6, session A4, this Conference.
2. S. 0. Dean, et.al., USAEC Report Wash-1295 (1974).
3. N. P. Busharov, et.al., "Chemical Sputtering of
Graphite by 1i Ions," I. V. Kurchatov Inst.
Report, Moscow (1975) (in Russian).

,,o va

Upcoming Pages

Here’s what’s next.

upcoming item: 5 5 of 5

Show all pages in this article.

This article can be searched. Note: Results may vary based on the legibility of text within the document.

Tools / Downloads

Get a copy of this page .

Citing and Sharing

Basic information for referencing this web page. We also provide extended guidance on usage rights, references, copying or embedding.

Reference the current page of this Article.

McAlees, D.G.; Bettis, E.S.; Huxford, T.J. & Marcus, F.B. Physics and engineering aspects of the Oak Ridge experimental power reactor, article, January 1, 1975; Tennessee. (https://digital.library.unt.edu/ark:/67531/metadc865751/m1/4/ocr/: accessed May 26, 2019), University of North Texas Libraries, Digital Library, https://digital.library.unt.edu; crediting UNT Libraries Government Documents Department.

International Image Interoperability Framework (This Page)