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====Summary==== In a [[ThreeDimensionalConfigurations/RiemannTypeI#Try_Again|separate discussion]], we have shown that, as viewed from a frame that "tumbles" with the (purple) body of a Type 1 Riemann ellipsoid, each Lagrangian fluid element moves along an elliptical path in a plane that is tipped by an angle <math>~\theta</math> about the x-axis of the body. As viewed from the (primed) coordinates associated with this tipped plane, by definition, z' = constant and dz'/dt = 0, and the planar orbit is defined by the expression for an, <table border="0" cellpadding="5" align="center"> <tr> <td align="center" colspan="3"><font color="maroon">'''Off-Center Ellipse'''</font></td> </tr> <tr> <td align="right"> <math>~1</math> </td> <td align="center"> <math>~=</math> </td> <td align="left"> <math>~\biggl[\frac{x'}{x_\mathrm{max}} \biggr]^2 + \biggl[\frac{y' - y_c(z')}{y_\mathrm{max}} \biggr]^2 \, .</math> </td> </tr> </table> <table border="0" cellpadding="10" align="right" width="30%"><tr><td align="center"> <table border="1" align="center" cellpadding="8"> <tr><td align="center"> ''Tipped Orbit Frame'' (yellow, primed) <br /> </td> </tr> <tr> <td align="center">[[File:TippedAxes03.png|350px|Tipped Orbital Planes]]</td> </tr> <tr><td align="center"> Given that b/a = 1.25 and c/a = 0.4703 for our chosen [[ThreeDimensionalConfigurations/ChallengesPt2#Example_Equilibrium_Model|Example Type I Ellipsoid]], we find that, <math>~\theta = - 1.18122 ~\mathrm{rad} = -67.68^\circ</math>. </td> </tr> </table> </td></tr></table> Notice that the offset, <math>~y_c</math>, is a function of the tipped plane's vertical coordinate, <math>~z'</math>. As a function of time, the x'-y' coordinates and associated velocity components of each Lagrangian fluid element are given by the expressions, <table border="0" cellpadding="5" align="center"> <tr> <td align="right"> <math>~x'</math> </td> <td align="center"> <math>~=</math> </td> <td align="left"> <math>~x_\mathrm{max}\cos(\dot\varphi t)</math> </td> <td align="center"> and, <td align="right"> <math>~y' - y_c</math> </td> <td align="center"> <math>~=</math> </td> <td align="left"> <math>~y_\mathrm{max}\sin(\dot\varphi t) \, ,</math> </td> </tr> <tr> <td align="right"> <math>~\dot{x}'</math> </td> <td align="center"> <math>~=</math> </td> <td align="left"> <math>~- x_\mathrm{max}~ \dot\varphi \cdot \sin(\dot\varphi t) = (y_c - y') \biggl[ \frac{x_\mathrm{max}}{y_\mathrm{max}} \biggr] \dot\varphi </math> </td> <td align="center"> and, <td align="right"> <math>~\dot{y}' </math> </td> <td align="center"> <math>~=</math> </td> <td align="left"> <math>~y_\mathrm{max}~\dot\varphi \cdot \cos(\dot\varphi t) = x' \biggl[ \frac{y_\mathrm{max}}{x_\mathrm{max}}\biggr] \dot\varphi \, .</math> </td> </tr> </table> We have determined that (numerical value given for our [[ThreeDimensionalConfigurations/ChallengesPt2#Example_Equilibrium_Model|chosen example Type I ellipsoid]]), <table border="0" cellpadding="5" align="center"> <tr> <td align="right"> <math>~\tan\theta</math> </td> <td align="center"> <math>~=</math> </td> <td align="left"> <math>~ - \frac{b^2 \beta \Omega_2}{c^2 \gamma \Omega_3} = -2.43573\, , </math> </td> </tr> <tr><td align="center" colspan="3"><b><font color="red">This definition of tan(θ) is inconsistent with all others!</font></b></td> </tr> </table> where, as has also been specified [[ThreeDimensionalConfigurations/ChallengesPt3#betagamma|in an accompanying discussion]], <table border="0" cellpadding="5" align="center"> <tr> <td align="right"> <math>~\beta</math> </td> <td align="center"> <math>~=</math> </td> <td align="left"> <math>~ - \biggl[ \frac{c^2}{a^2 + c^2} \biggr] \frac{\zeta_2}{\Omega_2} = +1.13451 </math> </td> <td align="center"> and, </td> <td align="right"> <math>~\gamma</math> </td> <td align="center"> <math>~=</math> </td> <td align="left"> <math>~ - \biggl[ \frac{b^2}{a^2 + b^2} \biggr] \frac{\zeta_3}{\Omega_3} = +1.80518\, . </math> </td> </tr> </table> We also have determined that, <table border="0" cellpadding="5" align="center"> <tr> <td align="right"> <math>~\biggl[\frac{x_\mathrm{max}}{y_\mathrm{max}} \biggr]^4</math> </td> <td align="center"> <math>~=</math> </td> <td align="left"> <math>~ \frac{a^4 (c^4 \gamma^2 \Omega_3^2 + b^4 \beta^2 \Omega_2^2)}{b^4 c^4(\gamma^2\Omega_3^2 + \beta^2\Omega_2^2)} ~~~\Rightarrow ~~~\frac{x_\mathrm{max}}{y_\mathrm{max}} = 1.26218 \, , </math> </td> </tr> <tr> <td align="right"> <math>~{\dot\varphi}^4 </math> </td> <td align="center"> <math>~=</math> </td> <td align="left"> <math>~ \frac{a^4}{b^4 c^4} \biggl(\gamma^2\Omega_3^2 + \beta^2\Omega_2^2 \biggr) (c^4 \gamma^2 \Omega_3^2 + b^4 \beta^2 \Omega_2^2) ~~~\Rightarrow ~~~ \dot\varphi = 1.59862\, , </math> </td> </tr> <tr> <td align="right"> <math>~\frac{y_c}{z_0}</math> </td> <td align="center"> <math>~=</math> </td> <td align="left"> <math>~ -\sin\theta ~~~\Rightarrow~~~~ \frac{y_c}{z_0} = -0.92507 \, .</math> </td> </tr> </table>
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