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72 lines
2.8 KiB
72 lines
2.8 KiB
\chapter{Conclusions}
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\begin{enumerate}
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\item {A simple three degree-of-freedom code, \SLAP ,
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has been written to approximate the eccentric impact response
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of a deformable body.
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Nonlinear load
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displacement characteristics and friction effects are included. The
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code has been verified experimentally and analytically. The code
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interfaces with Department
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1520 plotting codes to provide convenient
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graphical output.}
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\item {The secondary impact velocity of a body
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can be conveniently estimated using only the length
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and radius of gyration. Slapdown (velocity at secondary impact higher
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than the primary impact velocity) cannot occur for length to radius of
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gyration ratios less than two.}
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\item {The amount of energy absorbed in the initial impact is the most
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important parameter associated with the nose spring characteristics.
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For linear elastic springs, the
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spring rate (stiffness) of the nose spring is unimportant.}
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\item {Friction, for geometries and coefficients reasonably associated
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with transportation casks, has a small effect on secondary impact
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velocity. There is an optimum value (one which minimizes the
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secondary impact velocity) of coefficient of friction based on the
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load displacement characteristics of the nose spring and on the object
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geometry. Sufficient
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friction can increase the severity of the
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primary impact
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to values greater than those
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experienced for the flat side impact. This can make the
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primary impact at a shallow angle the controlling impact event.}
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\item {The following scaling parameters have been verified for nonlinear
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as well as linear load displacement characteristics (one G field
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neglected):}
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\end{enumerate}
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\begin{table}
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\begin{center}
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\caption{Summary of Relationships for Scale Model Testing}
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\makeqnum
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\begin{tabular}{||l|c||}
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\hline
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\multicolumn{1}{|c}{Parameter}
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&\multicolumn{1}{|c||}{Scaling Relationships}\\
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Geometry and & \\
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Initial Conditions: &\\
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\quad Overall Length & $l_{sm} = l_{fs} \times (Scale)^{1}$\\
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\quad Mass & $M_{sm} = M_{fs} \times (Scale)^{3}$\\
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\quad Moment of Inertia & $I_{sm} = I_{fs} \times (Scale)^{5}$\\
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\quad Spring Constants & $K_{sm} = K_{fs} \times (Scale)^{1}$\\
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\quad Initial Velocity & $V_{sm} = V_{fs} \times (Scale)^{0}$\\
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\quad Initial Angle & $\theta _{sm} = \theta _{fs} \times
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(Scale)^{0}$\\
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\hline
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Results: & \\
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\quad Linear Accelerations & $a_{sm} = a_{fs} \times (Scale)^{-1}$\\
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\quad Angular Accelerations & $\alpha _{sm} = \alpha _{fs} \times
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(Scale)^{-2}$\\
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\quad Linear Velocities & $V_{sm} = V_{fs} \times (Scale)^{0}$\\
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\quad Angular Velocities & $\omega _{sm} = \omega _{fs} \times
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(Scale)^{-1}$\\
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\quad Linear Displacements & $\Delta _{sm} = \Delta _{fs} \times
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(Scale)^{1}$\\
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\quad Angular Displacements & $\theta _{sm} = \theta _{f} \times
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(Scale)^{0}$\\
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\hline
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\end{tabular}
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\end{center}
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\end{table}
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