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

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where B is a coefficient;<br />

n is the exponent equal to 0, 1, 2, with uniform heating,<br />

linear <strong>and</strong> quadratic variation in the temperature gradient, respectively.<br />

We further assume that the temperature <strong>of</strong> the shell isiconstant<br />

throughout its thickness.<br />

SS<br />

is<br />

As indicated, the relative strain <strong>of</strong> an eiement during heating<br />

determined by formula<br />

88t+8 • y,<br />

S~y<br />

where stis<br />

Sis<br />

<strong>of</strong> its deformation.<br />

tt<br />

the thermal strain <strong>of</strong> a free element;<br />

the elastic strain <strong>of</strong> an element due to the constriction<br />

For a cylindrical shell relative strains in the circular<br />

direction e = e + C are substantial <strong>and</strong> are easily converted<br />

to radial strain w with formula w - re., ginally<br />

W=Wt+Wy.<br />

Free thermal strain wt is<br />

known (Fig.:5.14d):<br />

w=rv= raAt.<br />

It is also known that the stress in the shell creates the7 elastic<br />

component <strong>of</strong> total thermal strain in the element w-. Finding it<br />

involves considerable difficulties.<br />

t|<br />

Elastic component <strong>of</strong> shell strain is<br />

for a temperature problem.<br />

fdund by common procedures<br />

a) We impose on a cold shell rigid bonds in the form <strong>of</strong> a<br />

rigid housing <strong>and</strong> then heat it to temperature t. <strong>The</strong>rmal expansion<br />

<strong>of</strong> the shell does not occur, compressive stress arises in it, <strong>and</strong><br />

on the surface a reaction from the rigid walis in the form <strong>of</strong> pressure<br />

•Rt" <strong>The</strong> same eff'z;6 tn be obtained if we compress a shell exp<strong>and</strong>ing<br />

to wt =rcAt by external pressure up to the initial parameter.<br />

522

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