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AiRAVATA
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Hello. As a good mathematician, I'm having troubles reading some constants for a PDE.
I'm modelling an elastic rod using the equation
[tex]
\rho A U_{tt} - N U_{xx} + E I U_{xxxx} = 0,
[/tex]
where "[itex]\rho[/itex] is the beam density, [itex]A[/itex] and [itex]I[/itex] are the area and moment of inertia of the beam cross section respectively, [itex]N[/itex] is the prescribed axial load and [itex]E[/itex] is the Young's modulus." (Nayfeh and Mook)
Now, in the literature, I've found numerical values defined as
[tex]k_{\parallel} = \frac{A E_{\parallel}}{L},[/tex]
where "[itex]E_{\parallel}[/itex] is the Young (stretching) modulus, [itex]A[/itex] is the cross sectional area of the beam and [itex]L[/itex] is the length of the beam", and
[tex]k_{\perp} = \frac{3 E_{\perp} I}{L^3}[/tex]
where "[itex]E_{\perp}[/itex] is the Young (bending) modulus, [itex]I[/itex] is the moment of inertia of the beam cross section and [itex]L[/itex] the length of the beam".
My question is the following:
How does the quantities [itex]k_{\parallel}[/itex] and [itex]k_{\perp}[/itex] relate to [itex]N[/itex] and [itex]E I[/itex] on the PDE?
I'm modelling an elastic rod using the equation
[tex]
\rho A U_{tt} - N U_{xx} + E I U_{xxxx} = 0,
[/tex]
where "[itex]\rho[/itex] is the beam density, [itex]A[/itex] and [itex]I[/itex] are the area and moment of inertia of the beam cross section respectively, [itex]N[/itex] is the prescribed axial load and [itex]E[/itex] is the Young's modulus." (Nayfeh and Mook)
Now, in the literature, I've found numerical values defined as
[tex]k_{\parallel} = \frac{A E_{\parallel}}{L},[/tex]
where "[itex]E_{\parallel}[/itex] is the Young (stretching) modulus, [itex]A[/itex] is the cross sectional area of the beam and [itex]L[/itex] is the length of the beam", and
[tex]k_{\perp} = \frac{3 E_{\perp} I}{L^3}[/tex]
where "[itex]E_{\perp}[/itex] is the Young (bending) modulus, [itex]I[/itex] is the moment of inertia of the beam cross section and [itex]L[/itex] the length of the beam".
My question is the following:
How does the quantities [itex]k_{\parallel}[/itex] and [itex]k_{\perp}[/itex] relate to [itex]N[/itex] and [itex]E I[/itex] on the PDE?
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