• Version
• 143 Downloads
• 2.51 MB File Size
• 1 File Count
• December 8, 2016 Create Date
• December 8, 2016 Last Updated

National Advisory Committee for Aeronautics, Technical Notes - Hydrodynamic Impact Loads in Smooth Water for a Prismatic Float Having an Angle of Dead Rise of 40°

Direct—reading design charts are presented for 21LS—T almninum—aJloy
flat compression panels having longitudinal straight—web Y—section
stiffeners. These charts make possible the direct determination of the
stress and all the panel proportions required to carry a given intensity
of loading with a given skin thickness and effective length of panel.

Design charts for wing compression panels have been presented in
several different forms. (See references 1 and 2.) In reference 3, a
form was developed which permitted the direct selection of proportions
for given values of the principal design conditions ~ intensity of
loading, skin thickness, and effective length of panel. This form also
made possible the ready determination of the proportions having minimum
weight to meet these conditions. The charts presented in reference 3
covered TBS-T alwnimzm—alloy flat compression panels having longitudinal
straight—web Y—section stiffeners. Similar charts for alps—m aluminum—
alloy panels with formed Z—section stiffeners are presented in reference It
and direct—reading design charts for 2hS—T alumimm—eJloy Y—stiffened
panels are presented herein.

Direct—reading design charts for 2148—!!! aluminum—alloy flat com—
pression panels with longitudinal straight—web Y—section stiffeners
having the properties and proportions given in tables 1 to 6 are pre—
sented in two forms in figures 2 to 11. In the first form (figs. 2 to 6),
the design conditions of intensity of loading, effective length of
panel, and skin thickness are incorporated in the ordinate Pi/ts and
the abscissa —£}’-_-. This form, having the design conditions incorporated
in the ordinate and abscissa, is the more useful for most design purposes
because the curves are more widely spaced and. interpolation is more
straightforward. In the second (alternate) form (figs. 7 to ll), the
average stress at failure '61: is plotted against Pi/ts as was done in
the summary plots of reference 5.