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

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Thus, the bend obtained from equation (5.14) is<br />

the shell as the result <strong>of</strong> its<br />

thermal loading.<br />

the total bend <strong>of</strong><br />

<strong>The</strong> procedure for determining w y <strong>and</strong> wp is shown in Fig. 5.111.<br />

Let us examine the stress <strong>and</strong> strain <strong>of</strong> the shell as a result<br />

<strong>of</strong> a given temperature gradient At.<br />

If the temperature gradient is a constant value, i.e., At const,<br />

then from equation (5.14) it is apparent that wIV = 0. <strong>The</strong>n<br />

w = w 0 + W = w ; w 0 = 0. Furthermore,<br />

Ehý Eh ast .<br />

r 2 D rD<br />

hence<br />

=wq-=raA; w' -w" =w'-W V= O;<br />

W =-raat+W 0;=O;<br />

W = W -- w=raAt.<br />

Thus, uniform heating <strong>of</strong> a free shell does not cause thermal<br />

stresses in it; shell deformation is equal to unconstricted thermal<br />

deformation.<br />

If<br />

the temperature gradient varies according to linear Iaw,<br />

i.e., Ar B 0 Blx, x it is apparent from equation (5.14) that<br />

w 1 Y=O; W•--w+Wq='w,,; U'-=-0;<br />

W Wq---!raAt--ra (B. + BIx);<br />

•dz.-=ra . 1 ; W"= 7A"' =w•IV=~O;<br />

w = - wy w= raAt =ra (Bo + 8 1 x).<br />

525

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