Gas turbine RIB?

[Gasturbine59]

just about done now, doing ground runs and checking for oil leaks etc!,

[Gasturbine59]

[Xk59D]

that has win written all over it

[Gasturbine59]

Thanks, still got to try it in the water!

[two stroke mick]

Gas Turbine

Very Well done. Just a though. Given that the deck has been recessed to accomdate the turbine unit have you fitted a bilge pump into this recessed area to empty out any water that will gather at that location? Otherwise the sloshing of seat water could ruin your turbine unit.

Regards

TSM

[Gasturbine59]

Hi, yes thanks for that, I do in fact have a large capacity auto bilge pump right at the bottom of the transom, you can see it in the "disc and coupling" photo, as you say sea water and turbines, ......bad news!
rgds

[John Kennett]

Have you got some sort of cowling to go over the engine, or will you run it as it is?

[Gasturbine59]

Hi John, I don't have any cowling at present!, the idea is to try it on a nice flat calm sea and get an idea of wash and spray, then re-assess, see if it's required.

[John Kennett]

It's going to get at least damp, and salty, even if the sea is flat. Is anything going to be particularly vulnerable?

[Gasturbine59]

Well mainly the intake, salt water will damage the gas producer turbine, chemical reaction at 800deg C !, very corrosive to the wheels!, so very much an experiment , there are plenty of timex wheels available for these engines, (some consolation?)

[Bartol]

You can always do a rinse dry run (motoring) at the end of the day. Most seaplane operators do it and get very few corrosion problems on the engine itself. If you intend to run it a lot, I would suggest a simple U-duct inertial separator.
Flying for 10 years from Isle of Man in all sort of weather, we never had a sea-related issue with turbines.
All the best with your project!

[Gasturbine59]

Thanks Bartol , great to hear from the voice of experience , my turbine ops has all been land based and even operating near the sea , numerous water washes had to be carried out!, ..........understandably the owners of their expensive turbines didn't want to take any chances, but as seaplanes and hovercraft go, you are down there in the ogin !!!

[John Kennett]

You've got two main issues: proper swamping where you stuff the boat or a wave breaks over the side, and the less dramatic but possibly more insidious effect of salt spray penetration.

I hadn't thought about seaplanes or hovercraft, and I guess neither are likely to have a major swamping. Hovercraft certainly produce an impressive volume of spray which they obviously cope with though which is encouraging.

[Gasturbine59]

yes, thanks john, you're right, I have been swamped by a massive wave in a fletcher 17, totally unavoidable , saw wave coming but unable to avoid!, the trouble with gas turbines is the vast amounts of intake air they need to consume!, which makes any kind of filter too restrictive., I need a wave guard at the least, to prevent it ingesting solid water!, Lol,

[John Kennett]

Could you have an intake with a baffle, or would that be too restrictive?

[Gasturbine59]

hi John
yes, I think something simple like that, in fact probably just a box, open at the bottom!?

[Iron Dials]

Hi GT,
Sorry to be another "expert on the sideline".

Is there a possibility of exhaust gas ingestion (into the engine) a possibility? More a refining question I suppose, I'm thinking of boat at standstill, light following breeze at low speed (although you're probably not planning on low speed)
Could you ultimately duct the exhaust through the transom? Would back pressure be a starting issue?

Do you need positive airflow into the intake? Would the engine tolerate side facing or rear facing ducted intake, mounted above waterline?

Good luck with your first run, looking forward to reading about it.

[Gasturbine59]

not at all!, they are quite interesting projects as although apparently simple, they are technically challenging to fit in strange places!, lol, there can be no back pressure in the exhaust tubes, very intolerant , the gas plume emitting from the stacks is truly amazing!, it completely clears the boat there are no leaky fumes!, I've burnt the tree high above the boat, whilst testing!, you can inject raw high pressure paraffin straight into the exhaust duct!, this produces a massive cloud of white smoke, which can then be ignited (special ignitor req,d ), a sort of afterburner , very good for boat shows!........all good fun?

[Iron Dials]

Originally Posted by Gasturbine59

I've burnt the tree high above the boat, whilst testing!

Brilliant

[Gasturbine59]

I found this on ebay for £3500 in the states, it is the core of the engine, the two right hand wheels are the gas producer turbine, they are spline connected to the compressor assy on the left, the two wheels in the "center right",are the free turbine, directly connected to PTO, they are just "blown round" by the gas producer on their right