Design and Stress Analysis of Extraterrestrial ... - The Black Vault

I
a
It is necessary that n > 1l. Ifthis is not the case, calculations
should be performed in gzeater detail with allowance for the plastic
flow of the material.
Laminated fuel elements
'"
A
A laminated fuel element whose diagram is presented in Fig. 2.19
is installed freely in, a housing. The quantities'E, a, At = t -to
are given. Find ax .
I
As is apparent rrom the figure, :the temperature gradient is
symmetric with respect to the axis of the fuel element. Accor'ding
to the common method of finding thermal stresses, we fix the fuel
element rigidly in the axial direction (Fig. 2'.19b) and find strtxýs
a1 from the reactive forces hrising from such a bracing:
"Jz • Ea 'A
,(2.27)
The factor 1/(1 - i) is introduced because of the two-dimerIaional
stressed stjte of the plaýta.' A detailed derivation of t~his form.ula
for a plate will be given in Chap'er MV.
, I
The application of a bopd leads to a violhtioh of the boundAry
conditions of the freely installed iplate. We reproduce the condA,.!ons
by the appliqation of a force which is equal and opposite to the
reactive force in the fixing:
Stress from this force is
M21
" Ealbdy.
-h"2
hI2
5'- 1 L'E IV .1, (2.28)
I -s1 - ,h (I - Oh bh -l
* 12