Search found 503 matches

by racketmotorman
Thu Jul 03, 2014 9:45 am
Forum: Unconventional, Multi-Mode and Hybrid Jets
Topic: Turbo cylinder?
Replies: 10
Views: 6674

Re: Turbo cylinder?

Turbos don't have a problem with "intermittent" flow to an IC engine unless the engine has less than 4 cylinders , if on a 2 cylinder engine then a large volume plenum is recommended to dampen out pulses ,I think I used a plenum of ~1.5 times engine capacity , the turbo rpm do change slightly as eac...
by racketmotorman
Fri May 02, 2014 10:39 pm
Forum: Gas turbine forum
Topic: Luc's Industrial Gas Turbines
Replies: 9
Views: 3545

Re: Luc's Industrial Gas Turbines

Hi Luc

LOL..............a simply little job ;-)

I'll think on it .

Cheers
John
by racketmotorman
Thu May 01, 2014 10:59 pm
Forum: Gas turbine forum
Topic: Luc's Industrial Gas Turbines
Replies: 9
Views: 3545

Re: Luc's Industrial Gas Turbines

Hi Luc Let me get this straight ....................you want to feed the output from the GT2560 into another GT2560 , this is even less likely to work , any freepower turbine will need to have a flow capacity twice the gas producers due to the lower gas densities and velocities achievable from the l...
by racketmotorman
Wed Apr 30, 2014 11:26 pm
Forum: Gas turbine forum
Topic: Luc's Industrial Gas Turbines
Replies: 9
Views: 3545

Re: Luc's Industrial Gas Turbines

Hi Luc Your GT4708R units aren't "working hard" , they're running rather cold so the relatively small turbine stage isn't a problem , once you get a turbine "working" with T I Ts of 900 C and above, the lowered density of the gases soon cause problems with undersized flow areas , we soon go into sur...
by racketmotorman
Tue Apr 29, 2014 10:25 pm
Forum: Gas turbine forum
Topic: Luc's Industrial Gas Turbines
Replies: 9
Views: 3545

Re: Luc's Industrial Gas Turbines

Hi Luc The GT2560R turbos won't work :-( With a 46.5mm comp inducer -1698 sq mms , we'd normally require a turbine exducer area at ~25% bigger , or 2122 sq mms or 52mm diameter , the GT2560R has a very small turbine wheel of 53mm inducer but with a 62Trim it only has an exducer diameter of ~41 mm .....
by racketmotorman
Tue Apr 29, 2014 10:14 pm
Forum: Gas turbine forum
Topic: Jet Snowmobile Project/Team
Replies: 35
Views: 7721

Re: Jet Snowmobile Project/Team

Hi Luc

Nice graphics :-)

Been in hospital for a couple of weeks so haven't been able to keep up to date on what you're up to .

Cheers
John
by racketmotorman
Wed Apr 09, 2014 3:59 am
Forum: Gas turbine forum
Topic: Jet Snowmobile Project/Team
Replies: 35
Views: 7721

Re: Jet Snowmobile Project/Team

Hi Luc The smaller first stage gap could be better due to the finer entrainment at that point not requiring a lot of air , downstream as the jet surface starts to get "rougher" the larger clearance will have the capacity to supply air into that rougher jet boundary layer . Have you looked at commerc...
by racketmotorman
Tue Apr 08, 2014 11:14 pm
Forum: Gas turbine forum
Topic: Jet Snowmobile Project/Team
Replies: 35
Views: 7721

Re: Jet Snowmobile Project/Team

Hi Luc LOL.....you're such a flatterer :-) ................heh heh , you should know I don't have an ego , flattery is wasted on me . Yep , making sense why you need those 2 ejectors now . Laminar flow downstream of the nozzle will keep backpressures to a minimum , is there any way you can add a cou...
by racketmotorman
Mon Apr 07, 2014 11:15 pm
Forum: Gas turbine forum
Topic: Jet Snowmobile Project/Team
Replies: 35
Views: 7721

Re: Jet Snowmobile Project/Team

Hi Luc Checkout the length of jet nozzle I used on my GT6041 http://jetandturbineowners.proboards.com/thread/78/garrett-gt6041-powered-kart?page=8 , I used a central " boss" tube and straightening vanes to produce a smooth laminar flow into the jet nozzle , the gases exiting a turbo exducer fed from...
by racketmotorman
Sun Apr 06, 2014 12:32 am
Forum: Gas turbine forum
Topic: Jet Snowmobile Project/Team
Replies: 35
Views: 7721

Re: Jet Snowmobile Project/Team

Hi Luc

From doing a few numbers your 2.9" nozzle should have been putting out ~40 lbs of thrust at 80,000 rpm even with those low temps , that very efficient comp wheel works a treat :-)

Yeh , industrial units need a big safety component , you got it pretty well spot on .

Cheers
John
by racketmotorman
Sat Apr 05, 2014 3:10 am
Forum: Gas turbine forum
Topic: Jet Snowmobile Project/Team
Replies: 35
Views: 7721

Re: Jet Snowmobile Project/Team

Hi Luc

What sort of P2 pressures were you running the GT4708 up to ??

Heh heh , ........800 C exhaust would have been "interesting" in that industrial use .

Cheers
John
by racketmotorman
Fri Apr 04, 2014 10:54 pm
Forum: Gas turbine forum
Topic: Jet Snowmobile Project/Team
Replies: 35
Views: 7721

Re: Jet Snowmobile Project/Team

Hi Luc LOL.....Theres no need for Jetspecs anymore , lotsa Youtube videos showing how to make a jet engine from a turbocharger using "stolen" info from the DIY Site .....................heh heh , its a pity most of them won't work properly though because the guys making the videos don't understand t...
by racketmotorman
Fri Apr 04, 2014 12:32 am
Forum: Gas turbine forum
Topic: Jet Snowmobile Project/Team
Replies: 35
Views: 7721

Re: Jet Snowmobile Project/Team

Hi Luc If only it was so easy to give simple answers to the Rules of Thumb question . ..........................there are just so many variable to consider,........... big turbo with narrow map high pressure capability vs small turbo with wide map but limited pressure , diesel vs petrol turbo , soph...
by racketmotorman
Wed Apr 02, 2014 10:55 pm
Forum: Gas turbine forum
Topic: Jet Snowmobile Project/Team
Replies: 35
Views: 7721

Re: Jet Snowmobile Project/Team

Hi Luc LOL.........I helped design Jetspecs , Jesse took my Rule of Thumb numbers from the Yahoo DIY Gas Turbines Site and put them into a workable Program , we spent months getting it "sorta right" , its not perfect but it does produce a working engine , so I'd still recommend a large combustor :-)...
by racketmotorman
Fri Mar 28, 2014 10:50 pm
Forum: Gas turbine forum
Topic: Jet Snowmobile Project/Team
Replies: 35
Views: 7721

Re: Jet Snowmobile Project/Team

Hi Luc The ABB turbos are very expensive :-( Yeh , Springer should be sued for false advertising , it really is all crap , just another poorly attempted money grab from unsuspecting guys wanting to build a turbine engine , thats why the DIY Gas Turbines Site was able to help out . Our thrust outputs...