Dan's Uniflow Steam Engine

[@michaelbauers8800]

Probably the most interesting model steam engine I have seen on youtube!

[@officialbritishtaxpayer5609]

A very clever arrangement and also a superb example of engineering.

[@colsanjaybajpai5747]

As usual fantastic. Ingenious arrangement

[@gary.solexa]

Clever blend of technologies in a very neat setup. Superb!

[@TheRedBaronDSI6]

Incredible engineering! Happy to have stumbled across this hidden gem.

[@HistoricSteamTV]

Solinoid activated steam engines make so much sense. Very nice work, I hope to be able to eventually build a 15kg 12v charging unit.

[@dude-hh9db]

I haven't seen any better small scale steam engine on the WWW. This is outstanding.

[@kyleb3754]

Exceptional engineering and creative solutions. Thank you for posting!

[@chasbader]

I love this video. Where can I buy one? My dream machine is a steam powered fatbike or trike... Ride it in the winter on the trails up here in Alaska. Throw some twigs in the boiler and go another 100 miles. Efficiency isn't an issue because we have a lot of wood. If I can't buy the engine, can you help me obtain or make the parts?

[@josepablolopezaguado6191]

Amazing! I'd like to be like you some day!

[@Lumpeeks]

Really nice job. I read about your efficiency measurements. I'm curious on what cut-off ratio it ran during the test. Or if you have some results with maximum possible expansion ratio (1:10 guess). If you ran at full throttle like 1:2 cut-off timing then going to 1:10 should bring 40% more efficiency, going from 10% to 14% overal. If valve travel allows (bigger scale) then exceeding 1:20 expansion will start attacking 20% overal efficiency. Thanks

[@wanglydiaplt]

Please tell me more! I'm struggling with design of a 3 cylinder poppet valve engine and it looks like Dan has been there done that much better than I ever could!. Are plans or kits available?

[@thebrokenbone]

beautiful job!

[@glassjb]

Anything I think of Dan's done

[@Doodlebud]

Ray Maxwell! Is that you!? I did my first engineering co-op with you!

[@ray3maxwell]

Yes that is me. Which company did you work for...Creo?

[@Latheman666]

Brilliant !

[@stevecummins324]

Wondering if it might be possible to guide a piston in a bore by replacing piston rings with hydrostatic slide bearings placed around the piston? Such bearings would move up and down with the piston. . if clearance between bearings and cylinder walls are tight, there'd be a minuscule flow out of such bearings. A small steam receiver could be built in the piston, and so to could flow resistors to provide the bearing stiffness. the air receiver would to have a source of high pressure fluid... a small non return valve to above the piston, could charge the air receiver up to full pressure on each working stroke. there would be a need to pressurise the receiver before running.. such could be done by a similar non return valve communicating to the exhaust post. A shut of valve in the exhaust and connecting the boiler directly to the exhaust would force steam into the receivers such an arrangement of hydrostatic bearings, would also ease the choice of materials that can be used for piston, and cylinder liner... of great benefit would be the avoidance of need for materials to be different/suitable to rub against each other, due to the clearances inherent in hydrostatic bearings. .. It becomes feasible to make both piston and cylinder liner out of invar. if both are made out of invar there is no problem with differential expansion along the cylinder bore. that should help keep the clearances tight, and also avoid bore wear.

[@amarug]

beautiful!

[@bigass197]

What are the materials he was talking about- what carbon composites and what ceramic ? Graphite maybe and what ceramics ? Plz more info :)

[@howardduckington6177]

bigass197 here you go this is the website to it www.kimmelsteam.com/gelbart-uniflow.html

[@bigass197]

+cameron bohard - Thank you :) !!

[@gregorymalchuk272]

@@bigass197 Polyamide with a certain % of graphite. Basically nylon with 10% or 15% graphite powder suspended in it. That's for the cylinder liner.

[@EitriBrokkr]

So when does the coil release the inlet valve?

[@gregorymalchuk272]

At a variable point in during the downstroke. Early for maximum expansion and economy, late for maximum power. The governor acts on the length of them the admission valve is opened (cutoff governed). I assume he is using a microcontroller to operate the governor.

[@whatever11ization]

Wonderful!

[@chicoxiba]

I love steam

[@wanglydiaplt]

Bashvalve??

[@gregorymalchuk272]

The piston bashes the intake valve open, but an electromagnet holds it open and controls the cutoff by determining how long it stays open.

[@andydingley3746]

Needs a microphone!

[@Zenas521]

and sub-titles.

[@matteroftim3]

I didn't really understoot the need of the valve of the piston.

[@DoRC]

Eduard Voicu the valve in the piston allows it to up stroke without having to push against increased pressure in the cylinder.

[@Lumpeeks]

It is also a good trick for a neutral operation in clutch less car installation. When throttle pedal is released the steam input is closed with external valve and the engine can keep "breathing" without counter force. The only drawback is that the cylinders gets cooled.

[@gregorymalchuk272]

Ordinary uniflow engines tend to have to operate with a condenser. If they operate at atmospheric exhaust, they have to have auxiliary exhaust ports to relieve the excessive recompression because the exhaust ports close too early as the piston comes up. This valve allows exhaust to continue to exit on the up stroke while maintaining the uniflow path of steam for high efficiency, the best of both worlds. It's a brilliant idea.

[@union310]

That knock should not be there

[@valeriyreiter4199]

Mechanical valve gear is more simple, more rigid and cheap. And uniflow engine requires additional valve for condesate removing

[@stevecummins324]

+Feuerkrieg NordMeer Why the concern over condensate/extra valve? For *this* design the inlet valve can also work as a pressure relief valve- any condensate trapped on an exhaust stroke will lift the inlet valve, and cause the condensate to be pumped back into the steam inlet. That avoids hydrolocking and it's damaging cylinder over-pressurization better than other designs. It's also incredibly easy to adjust the cut off. to blow of condensate run with more than 100% cut off. With both inlet and exhaust valves open at same time, condensate and steam will flows straight into the exhaust.

[@valeriyreiter4199]

steve cummins Only if you have a starter. If engine is large enough, inlet pressure can be more than 120 bar, so engine must be turned back and forth until the condensate will not be pushed out by live steam. Another thing is it can be efficient only in short RPM range. In low RPM you need more to reduce heat losses, but in high RPM you need almost clean cylinder. In single expansion cut off may reduce steam consumption a little bit, but in compound engines VVT for inlet and exhaust is necessary, I think. P. S. Sorry for not the best english

[@gregorymalchuk272]

@@stevecummins324 Exactly. This style of valve prevents the excessive recompression on atmospheric exhausting uniflow engines. And the electronic control allows easy and accurate control of timing, power, and efficiency, and would work well in transportation applications where the computer controlling the throttle and cutoff could automatically use full admission and low throttled pressure for starting, and then change over to full pressure and partial admission of steam cutoff once up to speed.

[@gregorymalchuk272]

@@valeriyreiter4199 Uniflow steam engines have highest efficiency of all reciprocating steam engines. More than most compound expansion types, and with much simpler operation and construction, and much better part load performance than compound expansion types. Uniflow steam engines were the last state-of-the-art technological advances in steam engine technology before they were finally surpassed by other technologies in the 1940s and 1950s.

[@baklazanivanovich7566]

int not a Uniflow Steam Engine because only 1 side valve intake!!!!!

[@gregorymalchuk272]

The critical part of "uniflow" is the unidirectional flow of steam from one end of the cylinder to another, so as to prevent condensation of fresh steam by cold cylinder walls which were cooled when the previous steam charge was exhausted through the same port at the same end of the cylinder.

[@MrRinghoe]

Hi Dan, very nice build ! If you just let it run on compressed air, let's say at 8 bar, how many watt´s will it develop ?