DIY jet engine - twin turbo first light off tests

This is raw and pretty much un-edited, what you see is the first proper light off tests of my latest engine. The throttle has yet to be calibrated, for safety the bypass return valve is wide open when the throttle position is 'idle', once i find the true start/idle position i'll set this with the burkert valve controller (after which i can eventually look for 100% and set this also)...starters are holding up well but get real hot after a few starts, aluminium clutches also holding out way better than the original carbon ones - so far had about 100 spin ups with little sign of overheat or wear. Found a pinhole leak near to the combustor drain, so that'll have to be pulled and repaired. Apart from that it's coming together nicely.. Softly, softly as they say :-)

Category:

Autos & Vehicles

Tags:

• +Jet
• +Turbine
• +Engine
• +Turbo
• +DIYgasturbines
• +twin
• +afterburner
• +reheat
• +dragster

[nickthesafe]

Back on the project again after a lengthy break - new start system has high pressure air nozzles on the turbines assisting the electric starters - the starting problems shown in this video were down to a safety cut out on the fuel system which kept tripping every time it lit up - it had three safety features on the fuel line of which the sensetive one has been removed. I admit it's a long movie but it sure helped me diagnose the problems!....

[7xchad]

what kind of elecctric motors spool the turbos fast enoughto start it? can they run reverse as i am using Holset "bastard" turbos that spin the opposite direction for mine.

[nickthesafe]

@7xchad Hi, they are Feigao brushless motors handling up to 1000w driven using 120A speed controllers who's PWM signal is derived from a pic chip programmed to gently ramp up the power so as to not overload the clutches reverse is easy by swapping around a couple of the three power leads.

[exspertwelder]

HHHHmmm thats the same set up that has been the main picture on the DIY yahoo group forever and the thing does not even run. I really don't see how that CC unit can support those two big turbos at the same time.

[nickthesafe]

@exspertwelder Hardly forever, I've only been working on it for four years!. And the numbers stack up as far as burner size, it's comparable to the allison 250 engine as far as mass flow and burner size / design. The flame tube with it's conical head swirler is also a feature of the allison... I could show you a video spitting flames and glowing turbines but that's not what this project is about, if you read the diygasturbines forum you'll know all about it. Thanks for looking.

[fab069]

this vid is too way long

[ben38619]

@nickthesafe what formula did you use for your combustor/flame holder?

[GliTCH11]

Dude, you are the fucking man. I know you'll have it running in a short while, but that's half the fun.

[highvoltagefeathers]

@nickthesafe I'm building a very similar engine, and the burner size looks about proportional to what I've seen in museums and other diy engines! I've looked at your blog and it seems as though you've got a pretty well-engineered burner-can too.

[stimps90]

I like:)

[exspertwelder]

I read it as I built one myself too. I was not saying anything negative about your work as I know it is dificult to get it all working right I was just making an observation is all...Thanks for the reply.