Steam Condenser Design / Layout – Steam engine exhaust

[Steve WithnellParticipant @stevewithnell34426]

I'm thinking about building one of these so I have "clean Steam" to go up the boiler chimney. These things seem to have three connections, one is the drain to empty the tank of the "dirty" oil/water condensate, one is the "clean" steam exhaust. Those I understand. The third connection is the input exhaust steam direct from the engine. This one I'm not sure how to deal with.

Should it be kept at the top of the tank and out of the water? Anyone got any pictures of the internal tank design?

TIA

Steve

[Steve WithnellParticipant @stevewithnell34426]

[MICHAEL WILLIAMSParticipant @michaelwilliams41215]

Hi Steve ,

I need to know more exactly what you are looking for :

A condenser reduces the steam to water and there is no exhaust at all . There may be additional functions in a condenser system to separate oil but only to make the output water clean enough to reuse .

To condense water is easy and there are many practical designs of condenser .

A separator on the other hand filters out the oil from the steam but little condensation occurs and the input steam leaves again still being steam . The filtered oil is drained off usually as a waste product .

Removing oil from steam without much pressure loss is more tricky and the common systems are :

Jet separators , perforated metal filters and containers of very loose spongy material . For exotic applications there are also granule filters and cyclone and centrifugal separators .

Michael Williams .

Edited By MICHAEL WILLIAMS on 09/04/2012 11:24:22

[Steve WithnellParticipant @stevewithnell34426]

THis is what caught my eye, but not sure what's happening inside! Basically I want clean steam up the boiler chimney and the oil captured as is suggested here:

http://www.mainsteam.co.uk/condensers.htm

Steve

[MICHAEL WILLIAMSParticipant @michaelwilliams41215]

Having a second look . Description on that site could be interpreted two ways .

Edited By MICHAEL WILLIAMS on 09/04/2012 16:14:40

[MICHAEL WILLIAMSParticipant @michaelwilliams41215]

Device shown seems to be like a full size jet or cyclone separator but much simplified . This is how full size ones work :

Steam in through the high level side connection , steam out through the top connection . Steam is always confined to upper zone of tank and does not pass through condensate .

Steam issues from side connection as a weak jet but immediately slows down as goes into the big void in top of tank . This causes oil and droplets to fall as 'rain' down into sump zone leaving cleaner steam to continue on and out of top connection .

Entry jets are usually tangential so that steam makes several spiral circuits before leaving giving more opportunity for droplets to fall together with some mild centrifugal separation . There are usually also various deflectors .

Drain valve has a pipe leading down to very near bottom of tank .

Probably on a model separator working at very low exhaust pressures a simple straight in entry nozzle and one simple deflector would do all that was needed .

[Sub MandrelParticipant @submandrel]

I have seen a decription of one of these for a loco. You need to keep the steam speed HIGH not low otherwise you will have no blast to draw the fire!

The way the one I tread about works is that the steam whirls around the chamber before exiting at the top through the blast nozzle. The oil is flung to the sides where it drains down.

Neil

[WearyParticipant @weary]

There is a description and sectional drawing of a cyclone oil separator as fitted to a 3.5" gauge 'Charles' In Model Engineer 9 Feb. 2001 Vol.186 No.4139 Pages 123/4.

Regards, etc.,

Phil

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