Talk:Flow through nozzles

jet

I notice that jet, the gem, is completely absent from Wikipedia! There's a bit about it here. It's the source of the term "jet black". — Hippietrail 00:37, 17 May 2004 (UTC)

More commonly used definitions should be noted

This article should at least note the fact that most chemical and mechanical engineers as well as many thermodynamicists more commonly define the parameter z as being (k − 1) / k, where the isentropic expansion factor k = c_p/c_v, rather than (c_p − c_v) / c_p. In fact, in my entire career 45+ years as a chemical engineer, I have never seen before seen z defined as it is in this article.

I think the definition of z should be changed to the more common usage that I noted above. What do others think? - mbeychok 05:50, 17 March 2006 (UTC)

• Where did the equation for the ideal velocity acquire the number 8 in front of the square root sign? It is incorrect and I am deleting it.
• The R in the equation as it now stands is NOT the "common gas constant", rather it is the specific gas law constant for a specific gas R_s. It is related to the universal gas law constant R thus: R_s = R/M where M is the molecular weight of the specific gas.
• The equation should include the integer 2 in side the square root sign.

Unfortunately, this very incorrect equation has now been spread all over the world as evidenced by how many hits it get when searching for "gas jet" on Google. I have decided to rewrite this stub completely. - mbeychok 19:57, 17 March 2006 (UTC)

Article has been completely re-written and re-named

I just finished redoing this article completely and expanding it as well. - mbeychok 07:35, 18 March 2006 (UTC)

merge to nozzle

I think this article has a strange title. I think this could be solved by merging into nozzle which is a bit weak atm. --MarSch 14:34, 13 April 2006 (UTC)

Good idea, but I think it might be even better if we merged Flow through nozzles, nozzle and De Laval nozzle. And perhaps called the resulting article "Rocket nozzles" as differentiated from the many other uses of nozzles? - mbeychok 15:36, 13 April 2006 (UTC)

Merged with other articles

This article has just been merged into a new article, Rocket engine nozzles, along with de Laval nozzle, Nozzle, and Exhaust velocity. - mbeychok 03:13, 15 April 2006 (UTC)

What the? You do know they aren't only used on rockets? They're used on jet engines, and they're also used on various chemical and fluid processing systems. Don't you think you should have discussed this?WolfKeeper 04:02, 15 April 2006 (UTC)

WolfKeeper: On Talk:Flow through nozzles some days ago, User:MarSch said he thought that Flow through nozzles should be merged with Nozzle. I responded that I thought it was a good idea and suggested that perhaps we should also merge them with De Laval nozzle. No one objected to that idea, although admittedly it was only out there for a few days. Why did I feel it was a good idea? Because after studying the three articles, it was quite obvious that they were about 98 to 99 percent devoted to the use of nozzles in rocket engines and jet engines and they overlapped each other. Earlier today, I also queried the Village Pump (see here) as to how to merge three articles and followed their advice on how to do it. After the relevant material was extracted from the three articles .. there were only a few words left related to non-rocket and non-jet engine topics.

You are quite right that nozzles are also widely used in various chemical and fluid processes ... but those three articles did not discuss those uses to any extent other than a few words. What we need now is an article entitled simply "Nozzles" and devoted entirely to non-rocketry and non-jet engine uses. Yes, I was quite aware of that and I have decided to start work on such an article in the next few days (see my To Do list on my user page at User:mbeychok). Would you like to join me in that? Or would you prefer to tackle it yourself?

I will watch for your response here on your Talk page. Regards, - mbeychok 04:55, 15 April 2006 (UTC)

There's lots of ways to skin this cat. The architecture was poor to start with, but I'm sorry the current one seems to have become worse. For example, the idea that turbojet nozzles should be discussed under an article called Rocket engine nozzles is just wrong. Making bold changes is one thing, but something like this needs more thought.WolfKeeper 05:25, 15 April 2006 (UTC)

Wolfkeeper: Please take about 10 minutes to read the new article Rocket engine nozzles slowly and carefully. Don't pre-judge it by its title only. There is no mention at all in the article's text of turbojet nozzles .. nor of any specific rocket engine or jet engine for that matter. As you will see, the article simply has some bit of history on De Laval nozzles and otherwise it is devoted to explaining how the De Laval (or convergent-divergent) nozzle generates supersonic linear exhaust velocities and thrust.

Oh well, in that case, Rocket Engine nozzles is exactly the right article name then, since it doesn't mention rockets at all. Oh yeah, and linking from jet engines to an article that doesn't mention jet engines is good why?WolfKeeper 06:45, 15 April 2006 (UTC)

You will also see that it includes an extensive "See also" section which includes Jet engine and the Category designations include the Jet engines category. I get the impression from your comments that you feel that jet engines have somehow been given short-shrift by this article. That certainly wasn't my intent. I simply took four overlapping articles about rocket nozzles that already existed and combined their content in a single article. I didn't think that was particularly "bold" and, with all due respect, I still don't think so.

It is now 11:20 PM in California and I will check here again in the morning for further dialogue. Regards, - mbeychok

I'm sorry, but I'm currently thinking there needs to be a revert or a major reorg of some kind; it's just not been well thought out at all.WolfKeeper 06:45, 15 April 2006 (UTC)

The general principle needs to be that the article name in some way relates to what's in the article. Right now, there's no connection. You've got a Rocket engine nozzle article that's not about rocket engine nozzles but contains de laval nozzle info, you've got a de laval nozzle article that's empty. The nozzle article which should be an overview you're planning to fill with stuff about fluid processing. I really truly do not understand where you are going with this; your edits seem bizarre.WolfKeeper 06:57, 15 April 2006 (UTC)

Wolfkeeper, please don't put words in my mouth. I did not say that the merged article was not about rocket nozzles. I said that it explained how a rocket nozzle creates thrust, and the De Laval nozzle is a prime example of that. What I did say is that the merged article doesn't mention or discuss any specific rocket engines of jet engines in any way. Neither did the original articles which were were merged. I think the title of the merged article is perfectly apropos to the explanation of how rocket nozzle work. - mbeychok 15:08, 15 April 2006 (UTC)

As for your comment about linking, I did not link "from" jet engines ... I linked "to" jet engines by including them in the See Also section. Please level with me and tell me if you have yet read the entire article. I repeat again, I simply merged the overlapping contents of articles which already existed. Reverting back to the original articles won't change the fact that they don't discuss turbojets or any other jet engines. Nor will it change the fact that they did not discuss other uses of nozzles. - mbeychok 15:08, 15 April 2006 (UTC)

I've looked at the mergers and I'm happy that flow through nozzle and exhaust velocity were merged into a bigger article. I don't think it was a good idea to redirect nozzle to rocket engine nozzle even though a large part of the text was about rocket engines. Mbeychok has already stated that he thinks there should also be a nozzle article for non-rocket engine uses so we are in agreement on that. According to the jet engine article, a rocket engine is an example of a jet engine, one which happens to be propelling a rocket. The jet engine article is also much further down the featured article path at a quick glance. It even discusses (engine) nozzles! I think it would be a good idea to consider jet engine as the main article and to try to use wikipedia:summary style to make everything which is too large a separate article, but also to make everything which is too small not a separate article. I have the feeling that rocket engine duplicates much of jet engine. Anyway... please comment. --MarSch 15:58, 15 April 2006 (UTC)

MarSch: I must say that I am surprised at your saying: I don't think it was a good idea to redirect nozzle to rocket engine nozzle even though a large part of the text was about rocket engines. Especially since it was your original idea to merge nozzle with Flow through nozzles. Here is your original idea:

I think this article has a strange title. I think this could be solved by merging into nozzle which is a bit weak atm. --MarSch 14:34, 13 April 2006 (UTC)

Have you changed your mind? - mbeychok 18:13, 15 April 2006 (UTC)