2 shaft bike project

[artsi]

Hi John

Thanks for advice. Actually i was planning to change the rubber lines to copper ones at least where hottest parts are.

What type of lines and fittings did you use in your bike and kart?

I bought the freepower wheel on local turbo rebuild shop. I don't know what turbo it's from. Inducter diameter is 170mm and ex 150mm tip width is ~20mm.

Cheers

Arto

[racket]

Hi Arto

Yep , copper pipe is good to use for the larger diameters , and I use automotive steel brake line for the smaller diameters, though have used copper for them as well .

Your freepower is a very large radial wheel , its probably from one of the "small" locomotive or marine turbos ............a good find :-)

Cheers
John

[artsi]

Hello guys.
It has been a while since the last post of this project. A lot of work has been done and the bike
Is ready now! 



Cheers, Arto

[artsi]

Here is some pictures of my latest gas generator build.
The engine is based of  holset hx55 turbo with 67mm inducer comp wheel. The combustor is reverse flow annular type with evaporators. 
It has done many ours of testruns and different configurations.
Biggest problems has been burned evaporator sticks. Replacing them with a inconel sticks solved the problem. I have kept egt temps 500-650c. Max boost pressure 3bar











Cheers,Arto 

[racket]

Hi Arto

Nice to see another bike nearing completion :-)

I'm a tad concerned about your gas producers NGV vanes not being tapered , ......once your gases pass through the NGV throats they then encounter a larger flow area which will then slow them down rather than maintaining velocity, there will be extra losses with this arrangement , also your evap tubes burning sorta indicates a bit too much length , how did you determine length and heating surface area ??

Cheers
John

[artsi]

Hi,John.

Thanks for the reply.

Good points there.

Actually i did make a new ngv section.

That picture is from the first version. Unfortunately i don't have picture of latest ngv.
I managed to salvage ngv vanes from big old turbo which have nice aerofoil and tapered shape.
Reason why i made this new ngv was due to high temps for early runs.
That could be partly caused by those badly shaped vanes like you mentioned.

I don't have much calculations for evaporator heating surface area. I just wanted to make very generous size combustor based on jetspecs. It could be a tad shorter but since it's running so well i might keep it that way. Those inconel600 tubes are holding pretty well too. For my experience the stainless steel evaps doesn't last very long at any combustor.

Cheers, Arto

[artsi]

Here is a video clip for running on idle:

youtu.be/gMseLRah5iM

Cheers, Arto 

[artsi]

And there's video from very first testrun of gas producer.

youtu.be/hXToWhzKJrI

Cheers, Arto 

[artsi]

Couple more pictures. 
I was so excited to get my bike to Finland's biggest motorcycle show last weekend. 
There were 57 thousand visitors during the weekend. 







Cheers,Arto 

[racket]

Hi Arto

Bike is looking good :-)

We only need ~6 inducer areas of heating surface for the tubes , so for your 67 mm inducer, ~21,150 sq mms of tubing surface .

I'll be looking forward to some "performance" numbers .

Cheers
John

[artsi]

Thanks, John

Ok, so i have 10mm id evap tubes and 190mm length.

So there are ~47728 sq mm of heating area.

That is over double times of area you suggested.

I will consider to make new shorter combustor if those evaps do fail in future.
Other option is of course to replace them with smaller diameter tubes.

Cheers, Arto

[racket]

Hi Arto

As long as the tubes are surviving, probably best to leave as is, you'll be getting very well vapourised fuel and good combustion .

But you might need to think about the flow area of those tubes though , generally ~10-12% of total flametube hole area is devoted to the tubes , thats only ~350-400 sq mms for a 67 mm inducer , at nearly 80 sq mms per 10 mm ID tube , thats only 4 or 5 tubes required , you might be getting combustion within the tubes.

Cheers
John

[artsi]

Hi. 

There is video of testing onboard starting system. 


youtu.be/WPUTtU_WUO4

Cheers, Arto 

[artsi]

I have been building this electric Starting system couple of months now. 
It uses a 1:8 rc buggy motor and esc. The motor gives power about 2.5kw with 22.2v lipo battery. 
It can easily spin the shaft about 30k rpm. From there the turbine accelerates to idle very easy. 

The starting clutch is bendix type witch i have made from brass and 13mm socket.

I really like this bike setup now. 
I can take it somewhere to ride with no external starting equipment needed. 

Next step would be making some sort of fadec autostart, but then my limited building skills take apart. 

Cheers, Arto 

[lukenz]

Hi Arto,

I was wondering if you would like to share a little more on the bendix clutch? Did you purchase the clutch from somewhere, if so where could I find one? If you manufactured it could you please share the details? 😎

Kind regards,

Luke