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

Function B(T) is found after determining function ' by graphic
and numerical differentiation.
As seen from the figure, the value of coefficient. B() is
Svariable in a certain segment -it corresponds to the segment of
Unsteady cree-i and is constant in the remaining segment - the segment
of steady creep. Function Q after a certain value grows
monotonically.. •Function p decreases shai'ply when J -near zero
and then, monotoni*aliy.
Thernrl' stresses
In studying thermal stresses we face two different problems.
The first problem is finding the thermal stresses -which appear
as a result of rapid heating or cooling of a junction or part. This
mode, although brief, corresponds to the -maximum temperature gradients
and, consequently, stresses. Decrease in these stresses can be
achieved by increasing unit firing time or starting time. For an
installation where the time must be minimal, stresses must be
designed for.
The second problem is
to calculate stresses which occur in
parts. as a- result of the effect of steady thermal fluxes and
their corresponding steady temperature gradients.
For very many elements this calculat16n.-is fundamental if
deformations corresponding ho these stresses do not go beyond the limits
of elastic. This calculation can be a reference for stress analysis
if thermal stre.-ses exceed the elasticity limit of the material
when plastic deformations accompanying these sti-esses dan not be
disregarded. Strength calculation for parts) in this ca~'e, must
be made with relaxation phenomena taken into account.
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