Talk:Perfect fluid

From Wikipedia, the free encyclopedia

WikiProject Physics This article is within the scope of WikiProject Physics, which collaborates on articles related to physics.
Stub This article has been rated as Stub-Class on the assessment scale.
??? This article has not yet received an importance rating within physics.

Help with this template This article has been rated but has no comments. If appropriate, please review the article and leave comments here to identify the strengths and weaknesses of the article and what work it will need.
This article has been automatically assessed as Stub-Class by WikiProject Physics because it uses a stub template.
  • If you agree with the assessment, please remove {{Physics}}'s auto=yes parameter from this talk page.
  • If you disagree with the assessment, please change it by editing the class parameter of the {{Physics}} template, removing {{Physics}}'s auto=yes parameter from this talk page, and removing the stub template from the article.

Yeah, merge it.---CH (talk) 01:27, 27 July 2005 (UTC)

Perfect Fluids and Incompressible fluids are different. A perfect fluid is an physical concept similar to an ideal gas. As the article says, there is no shear stresses or viscosity. These are frequently used in General Relativity. An incompressible fluid is one where the density does not vary, and div(u)=0. Incompressible fluids can have shear stresses and viscosity, and are therefore not "perfect". Incompressible fluids are often used in Fluid Mechanics and in Chemical Engineering. Due to the different definitions and usages of the terms, I would argue to keep the pages separate. Bluap 12:41, 28 July 2005 (UTC)

"Perfect Fluids and Incompressible fluids are different." Well of course, and it should be obvious that I know that. Where did I (or anyone) say otherwise? ---CH 02:47, 1 July 2006 (UTC)

Keep entries seperate. Perfect fluids are very compressible, in fact they are used as the source for most traditional cosmological models, whose main characteristic is that they expand.
Markdroberts (talk ยท contribs)

Well, the cosmological models the reader is most likely to have encountered in textbooks are dust solutions, which are perfect fluids with zero pressure. However, dust solutions are also very frequently used to model gravitational collapse, e.g. in the well-known Oppenheimer-Snyder model.

As for the merger, without reviewing I don't know who proposed this or why I thought it was a good idea. In June 2006 my reaction is that there are probably good reasons to have seperate articles on perfect fluids in physics in general and perfect fluid solutions in the sense of exact solutions in general relativity.

[edit] Students beware

I completely rewrote the Sept 2005 version of this article and thought I had been monitoring it for bad edits, but apparently not since I missed the comments in the preceding section. I am leaving the WP and am now abandoning this article to its fate.

Just wanted to provide notice that I am only responsible (in part) for the last version I edited; see User:Hillman/Archive. I emphatically do not vouch for anything you might see in more recent versions. I hope for the best, but unfortunately general relativity attracts many cranks, some of whom have been known to make various false claims regarding perfect fluids in gtr. In particular, several active WP editors are involved with fringe science research on alternative cosmologies and may edit this article to slant information in favor of their fringe viewpoint on topics allied to perfect fluids.

Good luck in your search for information, regardless!---CH 02:41, 1 July 2006 (UTC)