11/127 manned flight engine.

[racket]

Hi Guys

A little teaser to brighten your Covid days :-)

My mate Andrew of the Bike Project ... jetandturbineowners.proboards.com/thread/34/motorcycle-project and I are looking at making a "manned aircraft sized" pure jet engine .

4lbs/sec mass flow and a guaranteed 200 pounds of thrust at "cruise" , with a bit more at "takeoff" power settings .

We've been exploring the purchase of some Mitsubishi TF15 turbocharger bits , 127mm-5inch inducered comp with a 175mm exducer on a 150/127 mm turbine wheel with a 1/2" dia quill .

The 127mm exducer is 28% bigger in area than my 12/118 engine's 112mm exducer , the 12/118's 3.3 lbs/sec X 1.28 = 4.22 lbs/sec ....plenty :-) the 12/118 produced ~175 lbs of thrust at "cruise" , multiplied by 1.28 = 224 lbs

An 11 inch outer casing seems to be as small as we can go whilst still providing enough flametube cross sectional area for the inevitable short length when using the standard turbine shaft .

Bearings ...............brass of course , cheap and totally reliable.

Fueling .................Racketjectors as per Andy Ms 10/110 engine.

Hopefully our sourcing of parts continues along as per plans and we can get it built this year :-)

Cheers
John

[turboron]

John/Andrew, exciting project. Can you share prices of the components?

Thanks, Ron

[racket]

Hi Ron

Once we've completed our sourcing I'll be only too happy to pass on information , at this stage I'm hopeful of building this first "Proof of Concept" engine for ~$3,000 with my free labour , this has got to be an "affordable" engine for Experimental Class Aircraft .

I feel the compressor wheel best suited to our needs will be the KTS billet # D171 , 7+7 blades , 45 degree backsweep , 11mm tip height , there are other KTS TF15 wheels which are a bit larger with extended tips etc , but "compactness" is important with this engine , and at a 52 Trim the D171 wheel is "just right" , the 11mm tip height is a tad less than I'd like but we'll live with it.

Cheers
John

[enginewhisperer]

I now have a CNC milling machine and a few other useful tools so should be able to help out with some prototype parts for this

[jetjeff]

Hi John,

This will be interesting,,,building a turbine large enough to power an ultralight is a "for retirement" dream of mine.

Any thoughts on a U shaped combustion chamber (similar to the Williams WR2 design)?  Or a combustion chamber that sits aft of the turbine wheel (similar to the Swedish PAL design)?  It seems with using the standard turbocharger shaft, you're constantly fighting complete combustion with such a short combustion chamber.

I know you like bronze bushings, but this will require a heavy battery (or multiple batteries?)to drive the oil pump.

I have a Williams turbine wheel, possibly from an F-107 engine.

Regards

Jeff

[racket]

Hi Jeff

Yep , I've been considering an "aft" combustor , Solar T62 type , I'll wait until I have the bits "in my hand" and make a decision , the beauty with an aero engine is that extra engine length isn't usually a problem .

Gotta be "brass" , those precision ball races are too expensive and I don't want to have to go through a whole development program just to get them sorted,......... standard turbo setup = no worries .

LOL, heavy batteries won't be a problem considering the fuel burn rate , this is going to be a short duration flight unless you've got very deep pockets to pay for the fuel :-(

That Williams wheel needs a nice modern compressor wheel on the other end of the shaft :-)

Cheers
John

[jetjeff]

Hi John,

Have you ever considered pressing the standard turbocharger shaft into an interference fit tube (say with a .125"+ wall thickness), to add several inches to the length of the shaft (and to increase the diameter of the shaft)?  You'd have to machine a spigot to accept the compressor.

1/2" quill diameter seems awful small for such a large rotor, plus you could design the engine exactly like your previous designs (with a longer turbine shaft, and longer combustion chamber.

Williams rotor shafts were hollow in design, and even I could make a tubular rotor shaft that works.

Regards

Jeff



 

[racket]

Hi Jeff

I'd only consider extensions as a last resort, we'd like "off the shelf" replacement parts for convenience .

LOL, they do those sized comps with 7/16" bores for fitting onto HX82 shafts used in tractor pulling turbos , I think I'd be wary of that skinny a shaft though.

If I'd been able to make reliable contact with Yili Casting I was considering using an axial turb wheel , but its almost impossible to get an email to them , with an axial turb I would have had to make shafts , so an ideal length would have been easy to achieve ...........but beggers can't be choosers , I'll use whats available , all we can hope for is that theres no stuffups with the supplier, we're keeping everything crossed :-)

Meanwhile I've been doing research and some initial work on the front cover pattern .

Cheers
John

[Chuks]

good news.... happy to hear we will be seeing another build from You.
what do you think about fitting our turbo charger compressor wheel
in an axial turbine wheel with turbo standard brass and thrust bearing?

[racket]

Hi Chuks

Standard turbo bearings should be fine , the large industrial turbos with axial turb wheels use "brass" .

Cheers
John

[Chuks]

I believe there will be better compressor configurations from KTS but because compressor wont fit our TV94 or HX82 turbine shaft there are automatically useless. but if we make our shafts things might be better.
just thinking.

[racket]

Hi Chucks

KTS do a large wheel that fits a HX82 turb shaft but the flow from the comp is too much for the turb wheel to cope with , we need a big hole out before we can have a big hole in .

Cheers
John

[racket]

Hi Guys

Bit of an update

Some TF15 turb wheels and CHRAs are hopefully on their way , Andrew has been taking care of them.

Meanwhile I've been doing some comp wheel hunting as the KTS wheels are proving to be rather expensive , I've found a billet comp manufacturer that does a similar wheel , 128/175mm , but I need to purchase 10 of them as thats MOQ , but the individual cost are much more reasonable ............wholesale price vs retail price , they may be a bit more "industrial" and not quite as high spec as the KTS "tractor pulling" ones , but with a 128 mm hole in the front , they'll provide enough air ............gotta keep costs down :-)

The comps will hopefully only take a month to arrive , but the heavier hot end bits a bit longer as they're a lot heavier and will need to probably come by sea

Cheers
John

[racket]

Hi Guys

For a X Project



And the "Standard" wheel



Cheers
John

[slittlewing]

More than a 5" Inducer.. This is going to be extremely impressive to see being built!!

Look forward to more updates

Cheers
Scott