Difference between revisions of "User:Tohline/2DStructure/ToroidalGreenFunction"

From VistrailsWiki
Jump to navigation Jump to search
Line 67: Line 67:
</table>
</table>
</div>
</div>
This set of coordinate relations appear as equations 2.1 - 2.3 in [http://adsabs.harvard.edu/abs/1973AnPhy..77..279W Wong (1973)].  They may also be found, for example, within eq. (10.3.75) of MF53; in [http://dlmf.nist.gov/14.19 &sect;14.19 of NIST's ''Digital Library of Mathematical Functions'']; or even within [https://en.wikipedia.org/wiki/Toroidal_coordinates#Definition Wikipedia].  (In most cases the implicit assumption is that <math>~Z_0 = 0</math>.)
This set of coordinate relations appear as equations 2.1 - 2.3 in [http://adsabs.harvard.edu/abs/1973AnPhy..77..279W Wong (1973)].  They may also be found, for example, on p. 1301 within eq. (10.3.75) of [<b>[[User:Tohline/Appendix/References#MF53|<font color="red">MF53</font>]]</b>]; in [http://dlmf.nist.gov/14.19 &sect;14.19 of NIST's ''Digital Library of Mathematical Functions'']; or even within [https://en.wikipedia.org/wiki/Toroidal_coordinates#Definition Wikipedia].  (In most cases the implicit assumption is that <math>~Z_0 = 0</math>.)


=See Also=
=See Also=

Revision as of 23:18, 15 June 2018

Using Toroidal Coordinates to Determine the Gravitational Potential

NOTE:   An earlier version of this chapter has been shifted to our "Ramblings" Appendix.

Whitworth's (1981) Isothermal Free-Energy Surface
|   Tiled Menu   |   Tables of Content   |  Banner Video   |  Tohline Home Page   |


Here we build upon our accompanying review of the types of numerical techniques that various astrophysics research groups have developed to solve for the Newtonian gravitational potential, <math>~\Phi(\vec{x})</math>, given a specified, three-dimensional mass distribution, <math>~\rho(\vec{x})</math>. Our focus is on the use of toroidal coordinates to solve the integral formulation of the Poisson equation, namely,

<math>~ \Phi(\vec{x})</math>

<math>~=</math>

<math>~ -G \int \frac{\rho(\vec{x}^{~'})}{|\vec{x}^{~'} - \vec{x}|} d^3x^' \, .</math>

For the most part, we will adopt the notation used by C.-Y. Wong (1973, Annals of Physics, 77, 279); in an accompanying discussion, we review additional results from this insightful 1973 paper, as well as a paper of his that was published the following year in The Astrophysical Journal, namely, Wong (1974).

Basic Elements of the Toroidal Coordinate System

Given the meridional-plane coordinate location of a toroidal-coordinate system's axisymmetric anchor ring, <math>~(\varpi,z) = (a,Z_0)</math>, the relationship between toroidal coordinates and Cartesian coordinates is,

<math>~x</math>

<math>~=</math>

<math>~\frac{a \sinh\eta \cos\psi}{(\cosh\eta - \cos\theta)} \, ,</math>

<math>~y</math>

<math>~=</math>

<math>~\frac{a \sinh\eta \sin\psi}{(\cosh\eta - \cos\theta)} \, ,</math>

<math>~z - Z_0</math>

<math>~=</math>

<math>~\frac{a \sin\theta}{(\cosh\eta - \cos\theta)} \, .</math>

This set of coordinate relations appear as equations 2.1 - 2.3 in Wong (1973). They may also be found, for example, on p. 1301 within eq. (10.3.75) of [MF53]; in §14.19 of NIST's Digital Library of Mathematical Functions; or even within Wikipedia. (In most cases the implicit assumption is that <math>~Z_0 = 0</math>.)

See Also

Whitworth's (1981) Isothermal Free-Energy Surface

© 2014 - 2021 by Joel E. Tohline
|   H_Book Home   |   YouTube   |
Appendices: | Equations | Variables | References | Ramblings | Images | myphys.lsu | ADS |
Recommended citation:   Tohline, Joel E. (2021), The Structure, Stability, & Dynamics of Self-Gravitating Fluids, a (MediaWiki-based) Vistrails.org publication, https://www.vistrails.org/index.php/User:Tohline/citation