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Author Topic: Steam Jet Engine  (Read 30780 times)

rathikrishna

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Re: Steam Jet Engine
« Reply #50 on: December 04, 2010, 01:54:33 pm »

Oh..its a great stuff...and Sir is that engine in to   Pratt & Whitney JT3D or   JT8D-219  ...?  thanks for the detaled photograph...
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flashtwo

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Re: Steam Jet Engine
« Reply #51 on: December 04, 2010, 02:22:20 pm »

Hi,

Being in facitious mode - some would say it has less to do with the Whitney part of the company! {-)

It has more in common with the Rolls Royce Trent 900 in that it lacks any lubrication oil ! {-)

Ian.
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flashtwo

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Re: Steam Jet Engine
« Reply #52 on: January 18, 2011, 07:59:43 pm »

Hi all Mayhemers,

Just a quick note to say that "Vital Thrust", with its experimental steam jet engine, will be on its first outing to the Ally Pally London Model Engineering Exhibition this coming Friday, Saturday and Sunday.

It will be on the Blackheath Club stand at the kind invitation of SteamboatPhil.

Hope to see some of you there.

Ian.
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mogogear

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Re: Steam Jet Engine
« Reply #53 on: March 09, 2011, 03:44:05 am »

And what exactly happened at the debut of the JET  ????

I hope that photos were taken...as this has been an interesting topic to find!
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flashtwo

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Re: Steam Jet Engine
« Reply #54 on: March 09, 2011, 10:06:46 am »

Hi Mojogear,

Vital Thrust was shown a lot of interest at the exhibition, particularly by professional engineers whose attention was caught by the title of the exhibit being "Rankine Cycle Jet Engine", the Rankine being the heat engine cycle employed by power stations as opposed to the Brayton cycle of gas turbine jet engines.

One combined cycle (gas turbine plus steam turbine) power plant engineer wondered if the steam jet engine could be scaled up to replace a gas turbine, one advantage being the elimination of the gas turbine compressor losses (30%?).

Another engineer appreciated the lack of high tolerance machined parts (apart from the water feed pump), unlike a gas turbine that has to be carefully constructed, and also no balancing requirement, since the engine wasn't rotating.

A marine engineer pointed out that the engine had zero torque (something that I had not appreciated), because of its lack of rotating parts, which might be an advantage in marine propulsion.

There was a trio of professional boiler engineers, who normally worked on major supercritcal boilers; they were fascinated by the novalty of the engine and you could "hear" their brains ticking over as to the industrial applications that the design might hold.

I had a long discussion with an industrial chemist about the difficulty of transfering the high velocity energy of the gas flow into the slower moving water flow. This is the major problem in applying the engine to boat propulsion, without using a power turbine and a propeller.

Thanks for your interest

Ian
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flashtwo

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Re: Steam Jet Engine
« Reply #55 on: July 04, 2011, 06:51:13 pm »

Hi Mayhemers,

Just a note to say that I've not given up on "Vital Thrust" and its steam jet engine.

I've recently managed to source some 3/8th inch stainless tube in "small" quantities, so that a higher temperature boiler can be constructed and also a stainless tube welder that can do the couple of joints that I need. The original copper boilers were always on the verge of failing with the extreme steam conditions of 720degC and 20Bar.

As you can see from the Flash steam plant control thread, I been concentrating on getting the new vertical monotube boiler working. Now that job is nearly finished I shall be back on the jet engine project.

Ian.
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flashtwo

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Re: Steam Jet Engine
« Reply #56 on: October 04, 2011, 08:20:17 pm »

Hi Mayhemers,

At last things are moving again (literally) with “Vital Thrust” (VT).

I have heeded the advice of benjaml1 and gondolier88, and have tried directing a pure steam jet through the water, although, to be honest, I did expect the steam to condense before any energy transfer took place – not so as it turned out.

The new flash boiler has been built out of stainless steel tube (2x 3 metres 3/16th inch) for the hottest parts and copper (1x 6 metres 3/16th inch) for the cooler. The new boiler weighs in at 1.4kg which somewhat less the 2.6kg of the original.

Welding has been avoided by ensuring the silver soldered joint between the lengths are at the boiler rear and are shielded against the direct flame of the burner.

The outlet is a threaded collar with 15 turns per connecting pipe, again to avoid welding and to enable the steam nozzle connecting pipe to be removed.

 The steam nozzle (again threaded) is replaceable to enable different sizes to be experimented with – 1 and 2mm currently.

I’ve strapped an augmentor tube to the underside of VT (after extensive rebuilding of the hull) and directed the steam jet through it.

Using stainless, I’ve been able to run the boiler with very low feed flow from the electric pump without worrying about melting the pipe.

The boiler contains 500mm of copper pipe through which the butane/propane liquid fuel is vapourised before passing through an external gas cooler and then on to the gas control valve.

I’ve managed to get a very good water flow through the external tube, the velocity of which will always be relative to the boat – the faster the boat, the faster the water will enter the tube and be accelerated. In theory, with the steam jet velocity at hundreds of MPH, the water should still be accelerated even if the boat is travelling fast.

Obviously hull drag will be a speed limiting factor, but it will be interesting to see the performance on open water rather than in my test tank.

Tomorrow I shall fit a small rudder in the water jet flow and then down to Herne Bay model boat pond for a fun test run.

The attached photographs show the original boiler with its flow tube; the new boiler with its steam outlet going through a flanged collar; a close up of the steam jet nozzle: the general arrangement in “Vital Thrust” and the last photograph shows the external gas cooler.

Ian.
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flashtwo

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Re: Steam Jet Engine
« Reply #57 on: January 08, 2012, 11:55:13 am »

Hi,

"Vital Byte" and "Vital Thrust" will be exhibited at the annual London Model Engineering Exhibtion 20th to the 22nd January, Ally Pally. They will be on Stand S, "A Team Boatyard" alongside the 14ft HMS Daring and other large "items".

Looking forward to having a good old chin-wag.

Ian.
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kno3

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Re: Steam Jet Engine
« Reply #58 on: January 08, 2012, 11:45:57 pm »

Have you tested it on the pond yet? I'd be interested to hear about how it performs. A video would be great.
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vtsteam

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Re: Steam Jet Engine
« Reply #59 on: February 28, 2013, 08:47:21 pm »

Fascinating thread by Flashtwo, but regretably no report of results in the boat. Have the results been posted somewhere else on the forum?

 Thanks!

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flashtwo

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Re: Steam Jet Engine
« Reply #60 on: March 01, 2013, 02:39:00 pm »

Hi,
 
Martin took a video in 2010 at Wickstead and posted it on You-Tube under "Steam Jet boat".
 
I'm afraid there was an incident on its very first run when the electric water pump blew its fuse and the boat had to be rescued by a certain person in waders, who unfortunately interpreted the boiler burner flame as indicating that the boat had caught fire. Subsequently, he pushed the boat under water to douse the flames and in doing so saturated all the boiler lagging.
 
I managed to dry out all the electronics and put the boat back on the water (see video), but the saturated boiler lagging made the boat very heavy and absorbed a lot of the burner heat.
 
I have subsequently made many modifications to the system to try out various ideas and have come to the following conclusions:-
 
1). As a pure jet, the combined steam/combustion gas exhaust (at 240mph) contains mostly kinetic energy and little momentum. It is the momentum derived force that accelerates the boat.
2). The kinetic energy only becomes a force when it impinges on something not rigidly connected to the boat, e.g. another model boat on the pond, or a turbine on the boat.
3). The engine "stalls" if its exhaust is restricted by too much water, i.e. exhausting under water.
4). If a pure steam jet is used against the surrounding water most of the energy is lost by condensation, i.e. little kinetic or momentum is exchanged between the steam and the pond water.
 
Any pure jet propulsion system becomes more efficient the faster the vessel travels, because the relative speed between the vessel and exhaust velocity decreases and less energy is expelled in the kinetic form and more as momentum. This is why jet aircraft require full throttle on take-off and throttle back when upto speed where they are more efficient. For passenger aircraft the momentum is increased by using fan engines (contained props), which accelerate a large mass of air by-passing the engine core. Fighters still use a pure jet engine for high speed.
 
The only way to extract the energy, for the boat, is to gradually extract the kinetic energy without stalling the engine. One could put the gas exhaust through a highly geared turbine driving a conventional prop or, alternatively, gradually introduce water droplets that could pickup the kinetic energy. This way, the engine shouldn't stall and the kinetic energy will be recovered.
 
In the video, you may notice the unconventional "rudder". This is of my own devising and vectors the force by using the "Coanda" effect. The "Coanda" effect was discovered during the development of the first jet aircraft in 1910. The rudder was successful and doesn't restrict the exhaust, especially when going straight ahead.
 
The steam jet engine has extreme steam conditions of 710degC and 20bar, and the back end of the boiler runs at temperatures in excess of 910degC (the melting point of brass). Silver soldered joints do not survive!
 
I still want to develope the concept, but I must finish my monotube boiler boat first (see "Edwardian Steam Boat "thread). The monotube boiler has been successfully developed and is to transferred from my experimental boat "Vital Byte" to the new launch.
 
Thanks for your interest.
 
Ian
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vtsteam

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Re: Steam Jet Engine
« Reply #61 on: March 01, 2013, 06:24:35 pm »

Ian, thank you very much for following up and explaining more about how it works, both in practice and theory. I've noticed the same kind of thing, back  few years ago when I built pulse jets. Well I should say similar kind of thing, not the same.

It is very stimulating to think about still, and I'm grateful for all of the detail  you've posted, as well as your thoughts about it..
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hydragon

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Re: Steam Jet Engine
« Reply #62 on: December 25, 2015, 05:32:10 am »

Ian can you email me at hydragon@hotmail.nl,I want to ask you a couple of questions regarding the jet boat,thanks.
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flashtwo

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Re: Steam Jet Engine
« Reply #63 on: October 01, 2016, 10:52:16 am »

Hi Mayhemers,

Nothing is new......!

Just been looking through the Birmingham Library's Bolton and Watt Collection and have found this concept of a marine jet engine;_

MS 3147/3/553  STEAM BOAT MEMORANDA  WILLIAM CREIGHTON’S MEMORANDA AND SKETCHES  1815—1822
‘Envelope C – Propulsion; Dimensions’
29.  Sketches.  Patent Scheme.  Not dated.  Three sketches of boats propelled by air being blown out into the water at the stern.  The  first scheme features “farting out wind behind, the bubbles rising up an inclined plane to  make the boat go forwards!!!”

This document is with others dated 1815 to 1817.

I love the technical description "farting out wind behind" - I wonder if Frank Whittle would have described his jet engine as such (or perhaps not!)

Ian


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TailUK

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Re: Steam Jet Engine
« Reply #64 on: October 01, 2016, 11:23:34 am »

Last time I heard of anything like that some Japanese guys were driving them at American battleships!
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ballastanksian

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Re: Steam Jet Engine
« Reply #65 on: October 01, 2016, 03:30:05 pm »

Crikey, what with Geoff and his smoke generator system, various members experimenting with Computer based systems and your work on making a steam jet enegine, I reckon that we Model boat enthusiasts must be the most cerebral bunch in the historical/creative modelling hobby as a whole.

I hope you can upload some more footage of the VT family for us to see them in action.
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tutanka

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Re: Steam Jet Engine
« Reply #66 on: August 20, 2017, 10:02:21 am »

Await your results with great interest... :-))


Hello, I'm new user of tis thread. 
The PDX engine works in different manner.
We are talking od HBE=HYDROGEN BOND ENERGY.

HBE IS THE NEW SOURCE OF ENERGY.


HBE is very simple to understand and simple is build an working device similar PDX that use the thrust for run an hydroturbine for produce the electricity directly. We are talking of new type of chemistry that we can call Mechanical Chemistry. To the end HBE no need combustion but is released from water droplets when lost the electrons for impact.  You can use steam or compressed wet air as kinetic energy necessary for produce the HBE.
There are some example of HBE:


Henri Giffard - Steam Injector (very similar to PDX device)
Lord Armstrong/Michael Faraday - Hydro-Electric Machine
Peter Graneau - Arc explosion
Stan Meyer - Thermal Explosive Energy
Pistol Shrinp Effect
PDX device


All of these is made from HBE.. and I suggest to read papers made by Tucker Leavitt and Peter Graneau for open the mind to HBE. When you know how HBE is made you can build all device you want without limitations.



If you want watch an working HBE italian experiment https://www.youtube.com/watch?v=86ihwyJ63MU


Because HBE don't appear only for mechanical impact but also if water droplets are submitted to the infrared radiation


Infrared radiation from sun or thermal spark removes the bonding electrons from water droplets and are absorbed from air like an sponge..


Also the Stan Meyer Injector works in this manner!!

Cheers
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KNO3

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Re: Steam Jet Engine
« Reply #67 on: August 26, 2017, 07:59:04 am »

What is your video supposed to show? It is completely dark, one can't recognize anything going on.
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boneash

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Re: Steam Jet Engine
« Reply #68 on: August 26, 2017, 11:20:35 am »

About 2.3 mins you get some form of light production, presumably the infra red that Tutanka refers to.
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ballastanksian

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Re: Steam Jet Engine
« Reply #69 on: August 26, 2017, 06:02:57 pm »

If I were someone wishing to invest in this technology (like BMW who amongst others are now investing in electrolytics and hydrogas generation) I would be profoundly dissapointed in the dark and grainy footage. Get it properly lit with a description of how it works and then you will get lots of inerest and maybe investment. Most people watching such videos have neither the technical ability or accumen to build their own system so your friend is not at risk of loosing any patents pending/ IP rights.

It looks intriguing, but could look and sound so much more so  :-))
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tutanka

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Re: Steam Jet Engine
« Reply #70 on: August 26, 2017, 10:11:10 pm »


Mechanical impact or infrared rays released the electrons from water droplets..
inside PDX the steam condense inside the water and the water is anelastic like an wall.
The steam impacting with the water release the electrons that are absorbed from air like an sponge and HBE pushes the water under pressure..   In this condition HBE is released and you can obtain the thrust.
in my HV reactor I use infrared rays released from arc voltage..
When my breath sended inside the reactor comes into contact with the high voltage arc, it is released HBE generating light and heat..


Different ways same result
I hope that these words open your eyes.


Regards
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