Search found 333 matches

by JJG Koopmans
Sun Dec 22, 2019 3:20 pm
Forum: Live Steam
Topic: Lempor Blast nozzle design
Replies: 8
Views: 1617

Re: Lempor Blast nozzle design

For what it is worth, I used an orifice length of twice its diameter. As for their inclination, during the tests of Michaels front-end we found that the inclination that is mentioned by Lempor lovers choked the performance. I would like to suggest that a four-orifice unit should be seen as a bundle ...
by JJG Koopmans
Mon Dec 02, 2019 10:14 am
Forum: Live Steam
Topic: Which pressure gauge to use?
Replies: 27
Views: 4266

Re: Which pressure gauge to use?

Hi all, The report of the Committee on Locomotive Front Ends of the Master Mechanics Ass. of 1906 is also on line: https://babel.hathitrust.org/cgi/pt?id=mdp.39015012686153&view=1up&seq=253 This shows the diminished performance of petticoats. The other book of Goss is Locomotive Sparks, also online....
by JJG Koopmans
Fri Nov 29, 2019 2:12 pm
Forum: Live Steam
Topic: Which pressure gauge to use?
Replies: 27
Views: 4266

Re: Which pressure gauge to use?

About the four nozzles, it does not make sense to position them on the same level as a single orifice. The optimal distance is about 6-7 orifice diameters, so with 4 orifices they are closer to the chimney entrance. As for the petticoats, I wonder why nobody cares to look again at the Goss experimen...
by JJG Koopmans
Mon Oct 29, 2018 6:08 am
Forum: Live Steam
Topic: Using a steam indicator
Replies: 42
Views: 13100

Re: Using a steam indicator

Having done this exercise with a real steam locomotive, I might add some comments after reading the posts. As for the mechanics, make a new cylinderhead. Hole it, put the copper tube in, expand on the inside and solder it tight on the outside. My experience is that the condensed water in the tube pr...
by JJG Koopmans
Sun Jan 14, 2018 8:03 am
Forum: Live Steam
Topic: Union Pacific Big Boy in 3/4 Inch Scale
Replies: 122
Views: 54397

Re: Union Pacific Big Boy in 3/4 Inch Scale

@Rwilliams,
Thanks for the orifice data!
kind regards
Jos Koopmans
by JJG Koopmans
Mon Jan 08, 2018 7:44 am
Forum: Live Steam
Topic: Union Pacific Big Boy in 3/4 Inch Scale
Replies: 122
Views: 54397

Re: Union Pacific Big Boy in 3/4 Inch Scale

Highly interesting, thanks! Could somebody let me know what the internal diameter of the 8 exhaust orifices is of the original (1:1) locomotive? My drawing does not have that detail, thanks!
Kind regards
Jos Koopmans
by JJG Koopmans
Sun Sep 24, 2017 2:08 pm
Forum: Live Steam
Topic: Help Identifying & Valuing Train
Replies: 45
Views: 7936

Re: Help Identifying & Valuing Train

To give an idea about a working one:
https://www.youtube.com/watch?v=J-fVTjv70tI
kind regards
Jos Koopmans
by JJG Koopmans
Fri Jun 02, 2017 9:27 am
Forum: Live Steam
Topic: Help plumbing a vertical injector
Replies: 6
Views: 3174

Re: Help plumbing a vertical injector

Question for the injector users. If one puts the injector to one's mouth and blow through it would one feel suction
at the water inlet???
Kind regards
Jos Koopmans
by JJG Koopmans
Thu Apr 13, 2017 3:47 am
Forum: Live Steam
Topic: Stack exhaust design revisited: the 1 in 6 taper myth?
Replies: 281
Views: 44992

Re: Stack exhaust design revisited: the 1 in 6 taper myth?

In my thesis of 2005 I devoted one and a half page to the effect of the Strouhal number which has exhaust beat frequency in it. At that time I noted already the research outside locomotives indicated increased performance with pulsation. My point of view is that in design and momentum calculations o...
by JJG Koopmans
Tue Apr 11, 2017 5:42 am
Forum: Live Steam
Topic: Stack exhaust design revisited: the 1 in 6 taper myth?
Replies: 281
Views: 44992

Re: Stack exhaust design revisited: the 1 in 6 taper myth?

1) using someone's 1898 opinion is not a strong argument in a scientific debate 2) just Googling "pulsating flow diffuser" will give a load of articles with conclusions like: ".....(2) The time-mean pressure rise is larger than that in the steady flow, ..." just meaning that in a steam locomotive a ...
by JJG Koopmans
Sun Jan 08, 2017 5:53 am
Forum: Live Steam
Topic: Stack exhaust design revisited: the 1 in 6 taper myth?
Replies: 281
Views: 44992

Re: Stack exhaust design revisited: the 1 in 6 taper myth?

(@Law)As far as the Adams vortex blastpipe is concerned, it consists of two blastpipes of which the orifices are flattened into a bananashape. As such it allows flow between the blastpipes. It was generally considered successful, however, being a casting it could not be repaired from wear as welding...
by JJG Koopmans
Wed Jan 04, 2017 10:26 am
Forum: Live Steam
Topic: Running a British Injector above its rated pressure?
Replies: 29
Views: 5547

Re: Running a British Injector above its rated pressure?

Fred, Hot water is a problem for any injector, even for the 1:1 locomotives. The problem being that steam contains a lot of heat and has to be totally condensed for any effect. So above a certain water temperature there is insufficient condensation and the device will not work. kind regards Jos Koop...