ET Westbury flash boiler

[Russell FurzerParticipant @russellfurzer50760]

I have been poring over ETW and Benson's FS books. Both refer to this boiler as suitable for a diffuse burner ( and show a drawing of the burner, which had appeared in ME 1770 ( 1935). The boiler design does not appear in that issue and I can't find it in the index.

Benson says that he knows of no actual examples.

Has anyone built one? If so, how did it go?

Would the water drum mean that it needs to be treated as a pressure vessel and inspected/ certified etc ( I understand flash units do not)?

Does anyone know the original ME article that the design appeared in?

russ

[Russell FurzerParticipant @russellfurzer50760]

[Trevor Drabble 1Participant @trevordrabble1]

Russ,

For your information , this drawing is shown as fig 5.2 in the Benson book which I am about to put on sale. On page 69 of the same book fig 5.8 shows a design for an ETW diffused flame burner which may be suitable. Suggest you may find it useful if you could get to talk with Phil Abbott of the Blackheath Model Boat Club. Believe he also may still be the straight running secretary of the MPBA. Contact may be possible via our companion Model Boats web site ? Certainly Ive always found him to be a very helpful and knowledgable chap on the subject of flash steam. With respect to certification of the boiler, I would assume it would depend upon its bar-litre capacity , a point which I am sure Phil or any MPBA club boiler inspector would be able to clarify.

[cParticipant @c]

Your boiler diagram is reproduced on page 523 of issue 1777. Whilst a design for it was not published in ME, you may find the accompanying text useful.

Chris.

[Russell FurzerParticipant @russellfurzer50760]

Thanks guys.

a second Itech search found that article in 1777. Dunno why it didn't appear first go!

Russ

[Ady1Participant @ady1]

From no 2998

Flash steam hoilers
For a steam plant which is required to operate under the same conditions continuously (as in most marine
models) the flash steam boiler is very suitable for all except the smallest sizes. The boiler itself is the easiest
to make (not necessarily so to design) as it is just a length of tube (copper is all right for low superheat, and
stainless steel for the luxury article) with water pumped in at one end and steam extracted at the other. There
is no worry about safety as the tube will stand very high pressure, and the
amount of water in the tube is small even if it does burst.
The pumps for supplying the boiler are most conveniently driven by the
main engine in the very small plants, and can be identical in design and construction to the pumps used on
models of more conventional dimensions. The pump for my 10 in hydroplane is 1/16 in. bore and stroke
adjustable from 0 to 0.2 in., and has been used mostly on 0,1 in. stroke. It is of normal design with 1/16 in
stainless steel ball valves and rotates at one sixth engine speed, the engine being 0.2 in. bore and stroke single cylinder single-acting. When using pond water for boiler feed, filtration is essential; I have found cloth between two layers of fine gauze effective, and the area of filter should be as large as possible to ease the load on the suction side of the pump

[Ady1Participant @ady1]

From no 2589

[Ady1Participant @ady1]

I would guess that some means of atomising water from the supply side from the pump would make it easier and faster for converting water to steam…(surface area stuff)

Don't kno much about it at all though

[Ady1Participant @ady1]

A newer product which increases surface area for flash steam?

corrugated stainless steel tube

[MICHAEL WILLIAMSParticipant @michaelwilliams41215]

Hi Ady1 ,

(1)Nobody has ever reported trying it but it is possible in principle to burn a fuel/air mix direct in the water and obtain near 100% heat transfer with low pollution levels in a very small unit .

(2)Flash steam engines have been designed and actually built with no boiler as such – heated cylinder head or micro boiler on cylinder head can do it all .

(3) You mention atomising . Similar concept is to raise steam in an auxilliary boiler and then superheat in a secondary boiler . Raising wet steam from water and superheating steam are two different things really and need separate thinking .

For a simple flash boiler this could mean an entry section of large diameter pipe coils with slow flow rate and a secondary section of small diameter pipe coils with rapid flow rate .

Primary section gets milder heat and secondary section gets the more fierce heat .

Regards ,

Michael Williams .

[Ady1Participant @ady1]

Flexible 6mm stainless tube seems to be easy and cheap to get in the USA, 25feet for 16quid and useable to 800 degrees C

[Author]

Posts