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If the blade height is too low there will be high boundary layer drag losses (by necessity) and it also becomes very difficult to avoid high leakage losses.

gas turbines develop far more shaft power than steam turbines for a given net output, it would not be unusual for 60% of the power developed by the turbine stages to be used driving the compressor. Also the working fluid is less dense, in large part due to lower pressure ratios. So the volume...

Heh no. I just get obsessed with something technical and have to understand it sometimes.

I published it here: https://www.homemodelenginemachinist.com/threads/steam-turbines-spreadsheets-and-a-few-observations.36226/ It works without superheat, but there are occasional issues with calculating the steam density if the steam condenses too much in the stage. Note that my spreadsheet...

What's your superheat temperature? I'll feed in to my spreadsheet for an equivalent deLaval turbine and see what answer we get.

You might not have encountered a case of them, but they do exist: From what I've read about 150 m/s is the practical limit for liquid pumps, due to high stress on the impeller and heavy erosion (possibly due to Cavitation?) of components at higher speeds. Though that doesn't rule out some...

I think those higher speeds are for compressors. Gases being less dense than liquid put less stress on the impeller

The reason it's like this is your ludicrous pump impeller tip speed from the high RPM of the tesla turbine. Honestly this is kind of the problem for most single stage turbines, they want to spin way too fast for most loads aside from turbocompressors and electric generators. What will happen is...

Yes it is fluid density

This covers it pretty well. https://www.nuclear-power.com/nuclear-engineering/fluid-dynamics/centrifugal-pumps/eulers-turbomachine-equations/

Being that a centrifugal pump is not a positive displacement machine, the flow rate will be set by many variables, most notably the amount of restriction on the flow at the inlet and outlet. You can get an idea of the amount of pressure the impeller can generate at a given flow rate by using...

I was wondering how you'd do this, it looks good!

Basically what Roger said. 'Conventional' 2 strokes always have the problem that the exhaust port must be uncovered before the transfer port so as to blow down the exhaust pressure before scavenging begins. If you only have one piston (or two, 180 degrees out of phase) the exhaust must...

You can build your own. What you need is an ignition coil (almost any will do) a hall effect sensor module, a magnet, a battery, a suitable power transistor (a MOSFET or IGBT) and some resistors. Basically the hall effect sensor output would be used to control the gate of the power transistor...

Wouldn't you offset the exhaust piston crankpins a bit so the exhaust opens first but closes around the same time as the intake? I suppose that makes the balance issue even stranger.

The iron I use is Chinese made, grade FC250 which I understand to be a Japanese standard about the same as class 40. So it should be quite like dura-bar. I just flame mine with a torch to red heat briefly, then allow to air cool. In fact I don't even use a fixture, I just spread the ring over...

I have had plenty of success with a ductile iron cylinder and grey iron rings. I suspect the reverse configuration (ductile rings, grey liner) would also work, and grey iron for both rings and cylinder certainly does as demonstrated by automotive practice. I don't think ductile iron rings would...

Interesting idea. I think the main challenge with it will be the quality of the dowel pins, I know a lot of them are somewhat 'tri-lobed' due to flaws in the centerless grinding.

The area you point to at the top of the cylinder is a screw thread. Or do you mean further in near the hole? Anyway the main issue appears to be the plunger, I can see low spots on it where it was not burnished by the cylinder during running. I will lap the cylinder again to be sure it is as...