Turboshaft?

[elventu]

I bought it!
I have another question.
I found a marine turbocharger (from Volvo Penta) on ebay at the right price (~230€ shipped), from what I understood it is better for us to have a turbine scroll with a big a/r like the turbocharger used in engines like boat, generator etc, it seems to be in good conditions.

May it be a good choice?
I'm thinking that if it is of the right dimension for my project I can focus on it instead of using the smaller unit that I have, but that comes from engines that needs faster spooling (and thus smaller A/R).

[racket]

It could be a good choice , but depends on exactly how the turbo is configured , without details of wheel sizes etc etc , its hard to say .

[elventu]

Nov 18, 2018 19:53:56 GMT -5 racket said:

It could be a good choice , but depends on exactly how the turbo is configured , without details of wheel sizes etc etc , its hard to say .

I'm searching for informations on the web, but even with the OEM numbers I can't find anything useful.
I asked to the seller if he can take some measurements.
It must not be a huge turbo, it comes from a 140/190hp 2.4 diesel, it is the marine version of the Volvo V50 turbocharger.

Crossing some numbers, it is a Garrett gta2056v unit.
Maybe tomorrow I have useful informations.

On the ebay there are a lot brand new unknown make turbocharger.

Maybe 100/120€ for a new T04E means something in terms of quality...?

[elventu]

www.ebay.it/itm/NEW-Universal-T3-T4-T04E-63-50-A-R-Turbolader-Turbocompressore-T3-Flange/223085745358?hash=item33f0f254ce:g:4psAAOSwBWJbYrYT


www.ebay.it/itm/Volvo-Penta-D3-130-160-190-Turbo-Turbocharger-for-marine-boat/183510786178?_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20160908105057%26meid%3Df80c1518c72042f1bc0e5c69fb564a51%26pid%3D100675%26rk%3D3%26rkt%3D15%26sd%3D223085745358%26itm%3D183510786178&_trksid=p2481888.c100675.m4236&_trkparms=pageci%3A11929f72-eb9b-11e8-b6df-74dbd18039b1%7Cparentrq%3A29998cd61670aa16a5229368fff5f8a1%7Ciid%3A1

[racket]

The turb scroll looks fairly "fat"

[enginewhisperer]

I don't think that will make enough pressure to start a turbine engine, but it will blow a lot of air!

[elventu]

Nov 18, 2018 21:30:30 GMT -5 racket said:

The turb scroll looks fairly "fat"

Too much or it can do the job?

[elventu]

I hope it starts at least a small one.
I'm curious.

Nov 18, 2018 21:54:04 GMT -5 enginewhisperer said:

I don't think that will make enough pressure to start a turbine engine, but it will blow a lot of air!

[elventu]

I asked the seller for the turbine and compressor diameter and it seems he don't want to give me an answer.
So...
Maybe I decide to start with the turbocharger I already have.

The dimensions are similar between the two, it is a Garrett T2 and a KKK K26, maybe the K26 it is better, but from what I remember it have some wear on the compressor tips, the garret is in perfect shape.

At now I can't pick up them, so I'm working on the rest of the design.

[elventu]

I spent some time searching about the fan I bought.
It comes from a HP server fan assembly.

For sure isn't an automotive part...but..
It seems it push some air.

youtu.be/8BXZKXlKVQw

youtu.be/5LXWPuEZH3s

[elventu]

Today I built the electric control for the engine.
A simple circuit to avoid errors in the starting sequence (I call it anti-stupid system), in cascade to make possible the opening of the gas solenoid valve must be met three conditions, there must be oil pressure, the fuel flow control valve must be closed, and then the starting fan can be activated (in parallel with the ignition circuit) and the general gas solenoid valve opens.

Tomorrow I have to add to the board some other parts, a couple tension regulator for the tachometer instrument and the spark generator and some other things.

[elventu]

First step for the tachometer!
I connected all the stuff and do a short try to read my template, 50x black and white bands printed on a 120mm diameter.
It seems that the band are too small for being correctly detecded by the optical switch.

Tomorrow I try to do a better job, maybe with a different print.

[elventu]

The tachometer seems to be functional.
For the moment I can't try it with high frequency signal, because I'm limited to the ~4200rpm of my mini-mill and I haven't any usable disk of a diameter bigger than 120mm.
Then I tried to modify the template, initially I tried to make the 50x white band thin, but without result.

At the end I tried with a new template with 16+16 black and white stripes and it read them with no problem.

When I have the engine running I were able to see if it is functional at full speed.

If interested, on Ebay there is the frequency meter I have bought.

The system is made from six parts.
The frequency-meter (it is able to show rpm simply dividing the signal with the in-built divider), the Omron E3X, its optical fiber, and the tension regulator (I used a simple 7809 for the instrument​ and a step-up to rise and stabilize the 15V for the Omron, and a 1W-680 Ohm resistor (pull-up) for the signal.

[elventu]

Ignition coil, ignition cable and the oscillator circuit just arrived.

Maybe in the evening I can make some sparks!

[elventu]

Yesterday I put togheter the spark generator circuit!

After having some trouble caused by the mechanical education (always put all the washers that comes in a mounting kit! And I put the plastic washer under the screw that connect the collector of the power transistor, isolating it from the circuit...), now I have a functional spark generator.
I tried it with an old spark plug with the ground electrode removed, it works perfectly.
It gives me an arc up to ~6mm long, with less than one Ampere drain from the battery!
Not the powerful unit on the market, but for an engine running on LPG I think it is more than enough!
Yesterday arrived also the 12V-200W for the oil pump, in next days I have to design the coupler for the pump.