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

ih
Fig. 3.31. Disk element and forces acting on it during
rotation.
-In a radial direction three forces act on the element:
centrifugal force applied at the element's center of gravity,
dPc = dnro- 2 =wo 2 r 2 hd?•,r;
the force applied to the internal surface of element (on radius r),
dP, = *,rhd--;
the force-- applied to the external surface of the element (on radius
r + dr),
dP;, = aP, + d (dP,) = -•rhd? + d (,rhdd?) =
,rhd? + d (:,rh) d?.
element.
In a circular direction two forces dP = hdr act on the disk
W'hile projecting all forces onto the vertical axis, we.obtain
dPc- dP- dPI-
2pIP sin d--0.
2
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