Landspeed bike with DIY gas turbine

[racket]

Hi Anders

LOL..........Zen and the art of turbine building , good name for a book ;-)

Cheers
John

[Johansson]

Ha! If I ever write a book it will either be named that or "Angle grinder masturbation - The lost art form". ;D

[turbochris]

angle grinder mastrubation? Is this what I have to look forward to when i come visit? What kind of safety gear would one need for that?

that's the funniest shit I heard all day

[Johansson]

Oops, didn´t mean to let you in on that one just yet. You´ll just have to wait and find out yourself... ;D

[Johansson]

I silver soldered the syringe needle injectors to the fuel manifold today.







Propane is used to test the injectors and see if they flow equally, I had to change a couple of injectors that were jammed but after that I got an even flow over all 18 injectors.



Here is the fuel manifold in place, you can see the injectors pointing down the holes where the vapour tubes will be later.

[racket]

Hi Anders

Nice work ....................just like a "bought one" :-)

Once the evaps are in place it'll be easy to position the injectors so that they spray onto the wall of the evap , try and position them so that the fuel "spirals ??" down the inner wall so as to "wet" all of the wall surface and maximise heat transfer .

Not much more to do now :-)

Cheers
John

[Johansson]

Will do.

I try not to think about how far away a startup is, only what I will do the next time I go to the workshop. Less stress that way, and a pleasant surprise the day I find out that the engine is finished.

[metiz]

The level of precision and detail on your engine is amazing! can't wait to see the completed engine.

[ernie wrenn]

HAPPY BIRTHDAY TO YOU.... It can be rented out as candles....

Nice job! Brazing those little lines can be a pain, they creat a cappillary effect and draw the silver and flux into them.

Those tubes looked a LOT bigger in the package..

Ernie

[racket]

Hi Anders

I know what you mean about not looking too far ahead , it can become overwhelming , one small step at a time is all any journey is made up of no matter how long it is.

You are getting close though ;-)

Cheers
John

[Johansson]

I made the propane preheat nozzles today, three 0.7mm OD syringes pointing into vapour tubes in the bottom part of the flame tube. Don´t know if they will provide enough heat but time will tell. (Or perhaps John...









Now both the main injector ring and the preheat nozzles are finished and its feed lines coming through the front plate. A bit trickier to assemble the engine now since I have to allign the feed lines with the holes in the compressor housing when I fit the NGV/flame tube to the shaft tunnel, but it´s doable.



Impingement nozzle in the making, 3mm hole in a 4mm stainless tube should provide plenty of air at 200bar pressure.

[racket]

Hi Anders

3 preheat evaps will do the job , some of the micro engines only have one , you're getting plenty of work done over the Easter break .

I'd be getting some sealing caps on those fuel/gas lines pretty quickly , one small bit of rubbish getting in there and you'll have a blocked injector :-(

LOL, they start getting harder to assemble , price we pay for sophistication ;-)

How is the airflow past the start gas manifold , is there sufficient radial clearance between it and the outer can for air to get to the evap inlets ?

Cheers
John

[Johansson]

Good to hear that the preheat injectors will do the trick!

I´ll make sure to seal the lines off with some vinyl tape, the problem is that they cannot be capped when removed or installed through the comp plate. One thing I could do if I get metal filings inside the fuel ring is to fit a neodynium magnet to it, that will make the filings stick to the ring walls instead of wandering off to the syringe inlets.

Just like in the Iron Man movies, the kids will love it! ;D

The preheat line is only 6mm thick so there should be no loss of air going into the vapour tubes covered by it.

What is your opinion about a temp probe mounted to the shaft tunnel inside the engine so I can monitor the radiating temps and estimate if the airflow to that region is high enough?

Would a glow plug be enough to ignite the propane or do I need a spark plug to set it off? Could a glow plug survive being fitted directly to the flame tube after the teritary holes?

Cheers!

[racket]

Hi Anders

Yeh , getting the plumbing in and out of the comp cover without anything being ingested is a problem , the only way I get around it is to always do it with the open end pointing downwards , it would be possible to "vacuum" the plumbing if the unfortunate does happen and a bit of rubbish gets in there .

A probe would be a good safety measure for that first spoolup , but you'd need one with 200 deg C capability for the wiring just to cope with T2 temps .

The rather fragile glow plugs in the micro engines seem to survive in the primary zone , a more robust "diesel" one shouldn't have a problem

Summertime spoolup is a definite possibility, a very nice job of the build :-)

Cheers
John

[Johansson]

Luckily for me I always fit the plumbing with the open ends downwards, hopefully I have managed to keep them clean so far.

If one or more injectors gets blocked there is no harm done, the engine cannot get damaged by this as far as I can see.

I´ll see what I can do about the internal temp probe, if it turns out to be too tricky I think I´ll pass for now.

My thought was to use an RC engine glow plug since it is very small and can be fitted completely inside the engine casing, do you think it could be fitted in the flame tube lid without being overheated? That would make things a bit easier for me since I won´t have to route the wiring past the flame tube.

A first spoolup before the summer is over would be nice.

Cheers!