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For those who are interested in checking my working (I make no guarantees that I'm not a big old dummy making stupid mistakes), here's my steam turbine spreadsheet. A few notes: 1. Superheating is not considered, the turbine is assumed to be running on wet steam. 2. At present, it only does a...

I notice you can get foaming PLA filament. Could one do lost-foam method using a 3D print like that?

If there is pressure drop across the rotor that is doing work on the shaft there is reaction occurring, though it might be happening via a different mechanism from a parsons turbine...

Could you link the papers? I'm having trouble conceptualising how the Tesla turbine can act as a reaction turbine.

In an impulse turbine (and the Tesla turbine is one, as there is no change in pressure within the rotor) all of the change in enthalpy happens in the nozzles. Essentially, the nozzle expands and cools the gas, which results in an increase in the tangential component of the gas velocity. The...

It's certainly true for a bladed turbine. I think the point is probably moot anyway because Tesla turbines with supersonic tip speeds in steam are probably beyond the capabilities of most materials, the wheel will just explode. Instead use more reasonable subsonic speeds (which also.will better...

There's nothing to be gained using C-D nozzles if you don't want supersonic gas velocity. Note that the turbine is spinning, it sees only the difference in velocity between itself and the gas, so there shouldn't be shockwaves on the rotor even when the impinging gas is travelling at supersonic...

ADHD struck (damn me and my malfunctioning neurons) and I've spent a bunch of time I could have been doing stuff I'm supposed to do (like work) making a steam turbine design spreadsheet. Something that came up from this is that the speed of sound in steam is quite a bit faster than air: even at...

I've used borax as a bronze flux many times and my crucibles are holding up OK. It does seem to corrode the surface somewhat at the level the metal reaches, but the effect is very minor in my case and I think I could do countless pours without issue. Possibly the reason I get away with this is...

Indeed, and it runs at a peripheral velocity equal to about 1/2 the velocity of the steam being discharged from the nozzles, whereas a Tesla turbine needs to have a peripheral velocity almost equal to the velocity of the steam. So the De Laval needs less gear reduction and is subject to far less...

My thinking is pretty much the same. Though here's a question, where is the seal on a pump which works by having a very tight clearance between a long cylindrical piston and its mating cylinder, like one of your injection pumps?

I think your policy of picking your battles is a good one. I'd much rather be using my limited mechanical skills on something fun in the shop than crawling under my car, getting covered in dirt and scuffing my arms up trying to remove a faulty alternator pulley... which is the position I found...

You'd need a double-ended ignition coil, but those are easy to find as they're used in all kinds of small 2 cylinder engines.

In that case don't forget about filling up the crankcase volume so your crankcase compression ratio is high enough. You might have to use flywheel type crank just to take up the volume.

If your engine is 2 stroke, how is scavenge pressure provided?

Do you have the convergent part of the nozzle too? It's not in the drawing.

Curious that it won't start if too advanced. Is it kicking back in that case, like ignition is way too early? Regarding the exhaust spooge, it kind of sounds like your engine is wet stacking, which can be a problem for full sized diesels too. Usually a symptom of the load being too light for...

A bit of a tangent, but has anyone tried a De Laval turbine? Seems like a better match to normal RPM ranges and retains the simplicity of a pure impulse turbine. Though you would have to make a multitude of tiny blades.

I spent today doing some odds and ends parts of the engine project. The crankcase has been drilled and tapped for mounting brackets so I can bolt it to a base, I made a new washer for the timing gears, put the nylon cap on the front end of the cam, and made a starter dog and driver. After...

Have you tried advancing your injection timing? 20 degrees?