DIY Tesla Impulse Turbine

[Toymaker]

Instead of endlessly arguing/discussing which engine is more efficient, perhaps we could get back to the main subject of post #173, that being the method of generating electricity from a TT at full RPM.

 

[HMEL]

As has been pointed out, there are no practical TTs available for efficiency tests. They're mostly (perhaps all) one-offs and hobbyists creations.

Comparing power station, or ocean-going ship sized steam turbines to all the desk-top TTs is a bit of apples to oranges comparison. Study a desk-top sized power station turbine and I'm quite certain you'll find the efficiency drops considerably. For several fluid flow reasons, axial steam turbines don't scale down very well.

Several studies indicate TT rotor efficiencies can exceed 90% Wiki Tesla Page. Seems reasonable to believe that TTs have substantial growth potential. Because of their low manufacturing cost, I can see where TTs might be a good choice for residential power production.

I read the Wiki Page and found it to be very misleading. All heat engines are compared against the carnot cycle. As the primary tenant in thermodynamics is work and heat are equivalent , enthalpy is derived from these concepts. Boundary conditions are important. You can calculate an engine efficiency or a cycle efficiency. The wiki page uses these interchangeably in their analysis. I have yet to see any telsa calculations that demonstrate an efficiency of anywhere near 60%.

 

[steve schwartzkoph]

can anyone point out any uses of Tesla Turbine in the real world, a real product, not just a toy or a demonstration model ?

I posted this in May of 2023: "About 23 years ago when I was running my business, we built what I believe to be a true Tesla Turbine.
The Discs were 20" diameter and I believe there were 19 of them. They were no vanes or blades on them and just relied on the boundary layer of the Discs to rotate them. We made the first of 60 units and they were powered by a huge parabolic dish that turned water into steam from the sun. It even had a condenser to reclaim the water from the steam".

 

[Richard Hed]

I posted this in May of 2023: "About 23 years ago when I was running my business, we built what I believe to be a true Tesla Turbine.
The Discs were 20" diameter and I believe there were 19 of them. They were no vanes or blades on them and just relied on the boundary layer of the Discs to rotate them. We made the first of 60 units and they were powered by a huge parabolic dish that turned water into steam from the sun. It even had a condenser to reclaim the water from the steam".

OK, but what did it do?

 

[steve schwartzkoph]

OK, but what did it do?

Powered an electrical generator.

 

[The Ignoble Troll]

OK, so my point is this, the Tesla Turbine isn't used anywhere for anything for a very good reason, its inefficient, and there's no getting around that fact (hence not even the military would use it), so it never ceases to amaze me that people keep on building demonstration models of something that isn't practical, its a jee-wiz parlor trick engine with no applications, and a really lousy way of getting into actual turbines. its not like building a flame-licker engine that has no applications, in that case you've at least accomplished building most of the parts needed for an IC engine, but with the Tesla Turbine you haven't made a single blade, and that's what turbines are all about, gas or fluid flow around blades; aerodynamics, fluid dynamics, and thermodynamics, which are all extremely interesting and fascinating topics, but the Tesla Turbine doesn't get you there. my "rant cast" for the day, sorry, over-and-out...

Jet engines were the same due to flat compressor blades which caused minimal compression until someone figured out that they needed the blades to be tapered...


Work like Toymaker's work has an excellent chance of unlocking an overlooked detail that would let the turbines function as mathematics predicts...

 

[The Ignoble Troll]

As has been pointed out, there are no practical TTs available for efficiency tests. They're mostly (perhaps all) one-offs and hobbyists creations.

Comparing power station, or ocean-going ship sized steam turbines to all the desk-top TTs is a bit of apples to oranges comparison. Study a desk-top sized power station turbine and I'm quite certain you'll find the efficiency drops considerably. For several fluid flow reasons, axial steam turbines don't scale down very well.

Several studies indicate TT rotor efficiencies can exceed 90% Wiki Tesla Page. Seems reasonable to believe that TTs have substantial growth potential. Because of their low manufacturing cost, I can see where TTs might be a good choice for residential power production.

Are you familiar with FES?

 

[Toymaker]

Are you familiar with FES?

I know FEA = Finite Element Analysis,...but I'm a blank on FES.

 

[The Ignoble Troll]

I know FEA = Finite Element Analysis,...but I'm a blank on FES.

Sorry, Flywheel Energy Storage.


A cylinder(flywheel) is placed in a vessel under vacuum with non friction bearings. At one end of the cylinder is a set of coils.


The design seems exactly like you are after.


The coils can act as a motor to accelerate the flywheel to crazy speeds which it maintains almost indefinitely. To use the power, the same coils act as a generator and suck out the rotational energy.


They operate at tesla turbine speeds, if I remember correctly, and are highly efficient.


In terms of converting the high speed of the turbine into electrical power without a geared transmission - I would check out FES designs.


Your sketch is similar to these things.

 

[peterl95124]

I posted this in May of 2023: "About 23 years ago when I was running my business, we built what I believe to be a true Tesla Turbine.
The Discs were 20" diameter and I believe there were 19 of them. They were no vanes or blades on them and just relied on the boundary layer of the Discs to rotate them. We made the first of 60 units and they were powered by a huge parabolic dish that turned water into steam from the sun. It even had a condenser to reclaim the water from the steam".

so you prototyped this, and abandoned it after you measured the efficiency and decided that even solar panels which are pretty inefficient would generate more electricity ???

 

[steve schwartzkoph]

so you prototyped this, and abandoned it after you measured the efficiency and decided that even solar panels which are pretty inefficient would generate more electricity ???

I built the Prototype to my customers design and specifications. Somebody else built the parabolic dish to generate the heat and turn the water into steam. My customer did the testing. I have no idea how the testing went or if any of the other 60 units were built. I think their goal was power generation in third world countries.

 

[Lloyd-ss]

Instead of endlessly arguing/discussing which engine is more efficient, perhaps we could get back to the main subject of post #173, that being the method of generating electricity from a TT at full RPM.

Just an observation:
It is almost like there are 2 threads going on here. First, @Toymaker 's original hands-on efforts to build a TT in his shop. And then a second, more esoteric thread, in the parlor, with gentleman's smoking jackets and tobacco pipes and brandy, discussing the theory, practicality, and philosophy of the TT and similar devices, which add minimal assistance to the original intent of Toymaker, who is out in the shop getting his hands dirty.

Both are good discussions, but separate discussions. Just my tongue in cheek outside observation.

 

[The Ignoble Troll]

Just an observation:
It is almost like there are 2 threads going on here. First, @Toymaker 's original hands-on efforts to build a TT in his shop. And then a second, more esoteric thread, in the parlor, with gentleman's smoking jackets and tobacco pipes and brandy, discussing the theory, practicality, and philosophy of the TT and similar devices, which add minimal assistance to the original intent of Toymaker, who is out in the shop getting his hands dirty.

Both are good discussions, but separate discussions. Just my tongue in cheek outside observation.

More like pointy sticks then cigars, lately, but your point is well taken.


I think Toymaker has an incredibly neat project and goal. Not just something to sit under a plexiglass case but a functional apparatus. Poopooing the exstistential functioning of a tesla turbine isn't particularly useful when someone is actually working on cracking the elusive egg.

 

[Lloyd-ss]

In college I thought I knew what I knew. I have been diligently learning in my 50 years since college, (just because I love to learn), and I now realize that even though I now know so so much more, I also know that I really know so so much less.

@Toymaker , I think we are all interested in your project, and are all hoping you find it (at least) enjoyable. Like so many of the challenging projects on this forum, you are doing something that other mortals would never even attempt.

I am in the crowd watching and cheering from the sidelines.

 

[clockworkcheval]

In Zürich I seem to remember public transport buses ran with FES, and given the hilly town this was very effective.

 

[The Ignoble Troll]

Just to clarify I'm thinking just the motor designs plus maybe a magnetic coupler to allow slip, would be virtually bang on to the high-speed needs that Toymaker is after. I don't think he would need the flywheel.

@clockworkcheval
Really neat they were used in busses, they age a lot better then Li batteries, but I had never heard of them used in vehicles! That's incredibly clever. I wonder how they took joistling into account.

 

[The Ignoble Troll]

https://www.researchgate.net/figure...r-for-flywheel-adapted-from-85_fig7_350838094

 

[Lloyd-ss]

Aren't the electronics needed to tame the variable frequency and voltage output from a high speed alternator like toymaker sketched in post #173 already somewhat available. They may not yet cover the broad range that @Toymaker is ultimately looking for, but who knows what is being developed.
Just Googling for AC to AC variable frequency and variable voltage Input And Output Convertors yields some interesting results.

BTW, I have not seen any rare earth magnets polarized as you drew in #173, but I have used several round magnets together with 2 strips of steel to fashion a bar with that type of polarity. The magnets "resisted" being grouped as needed for that application.

 

[The Ignoble Troll]

Aren't the electronics needed to tame the variable frequency and voltage output from a high speed alternator like toymaker sketched in post #173 already somewhat available. They may not yet cover the broad range that @Toymaker is ultimately looking for, but who knows what is being developed.
Just Googling for AC to AC variable frequency and variable voltage Input And Output Convertors yields some interesting results.

BTW, I have not seen any rare earth magnets polarized as you drew in #173, but I have used several round magnets together with 2 strips of steel to fashion a bar with that type of polarity. The magnets "resisted" being grouped as needed for that application.

@Toymaker is an electronics (retired) wizard. I think it's form over function that he is after, because he seems highly capable of taking care of the function.

 

[The Ignoble Troll]

Tesla turbine that includes aerfoil blades

https://phys.org/news/2010-05-bladeless-turbine-tesla.html