Turbine Hydro?

[NoJoy]

Has anyone seen or tried this type of conversion. I would like to see the R/C version become more "life like" and a turbine engine would do the trick. Since the engines exist for jets and helicopters, what would it take for a 1/8 scale hydro. If this topic has been covered before, please show me the link.
Thanx.

[martin richards]

I can't remember whether it has been covered here but I seem to remember that the "experts" weren't to keen on the idea of water spray in the turbine. I can imagine a Miss Bud with the turbine screaming across a pond and that raises the thought of noise problems as well:eek:

[NoJoy]

Water Spray in the turbine could be a problem. The noise problem I am not too worried about. Thanx for the input though.

[pimp_squeak]

so long as you had the turbine appropriately shielded from bow spray it would be fine....

[Umi_Ryuzuki]

No one has ever explained their concern about water in the turbine. The exhaust turbines are designed to quickly vent the expanding gasses and the faster the gases are vented, the faster the turbine spins. It is not like jet engines are falling off airplanes in stormy weather.

The real Miss Budwieser is constantly being pummeled by 20-30 foot rooster tails. Never seen the engine have any problems. The only time they add extra protection on the turbine intakes is when they run in salt water. So obviously water gets into the engine compartment and the turbine.

There is a thread on a Turbine Miss budwieser model here, and it is currently up for sale.
http://www.rcuniverse.com/forum/Turbine_powered_miss_bud/m_1746461/tm.htm
Also check the links in the thread to MHZ, and their custom made exhaust turbine for powering boats.

If the guy that promised me a micro turbine had followed through, I would have gotten a boat running years ago. I had someone lined up to build the boat, and the person who was supposed to build the jet engine and exhaust turbine power transmission had my money.
I still hold that over him to this day. And once in a while show him where he can get parts. :rolleyes:

[thething84]

water spray in the turbine wouldn't be that much of a problem as long as it was only light spray. as the engine runs that hot that it would just turn to steam giving more air to burn. however alot of water would ba a problem. would need to properly sheald the intake so that water will not get in but air can

[Umi_Ryuzuki]

I e-mailed a couple of manufacturers just to gather and verify any information people would like to share on Turbines and Moisture/Water Ingestion.

The question:
Recently people have made proposals for turbine powered boats over
online bulletin boards. Some people have expressed concern about the
turbine ingesting water.

Could you expand on the abilities of micro turbines to tolerate moisture,
water spray, and complete submersion during operation, or catastrophic
sinking.



The ingestion of water will stop the engine immediately. The rapid drop in
metal temperature may warp or damage some metals in the turbine. The
bearings may or may not have to be replaced.

Water spray will at minimum, slow the engine down. Since water does not
compress, if any gets inside the front wheel the engine will stop, or, may
come apart in a mini explosion.

That's our opinion
FT

Frank Tiano Enterprises
3607 Ventura Drive East
Lakeland Fl 33811

www.franktiano.com website




I have asked for a better definition of "mini explosion". :confused:

:p
Umi

[CG Bob]

Research the archives and look for the January 2004 ssue of Marine Modelling International. On page 18, the following article starts: "Gas Turbines - The Future?". Excerpts from the article follow.
Wren gas turbines conceded that a large volume of water entering the turbine at speed would cause damage to the compressor, but this would be a relatively low cost repair and the main components of the engine would not be damaged.
The main question I asked was this: what would the effect be on the metal casing and turbione blades of a massive and sudden drop in temperature such as that would occur if the boat flipped over? The informed reply was that this sort of incident would not result in destruction of the unit. This reply was also the one received from AMT based in Amsterdam. AMT also said that in all such acccidents the compressor and bearings would be damaged and need replacing but compared to the total cost of the engine the cost of repairs was minor.

[NoJoy]

How much is the Turbine Miss Bud going for?

[lowdive]

water spray into a turbine engine can actually be beneficial. i'm part of a group on yahoo for do-it-yourself gas turbines made from turbo chargers out of cars, trucks, whatever! and this discussion comes up from time to time. the guys talking about it are talking about it in a good way, though. in fact, there is such a thing as water injection for turbine engines. sucking water through to your combustion chamber allows you to cool the incoming air further as it is compressed (and thus heats up) for a larger expansion of gases at combustion. you also drop your TIT (turbine inlet temperature) which can save on the wear and tear of your turbine and let you run at higher throttle. the other side of this is that introducing water to your turbine will accelerate the oxidation of certain metals and what not. considering that airliners go through rain, sleet, hail and snow i don't think it's that big of a deal. the most common thing i think would happen from sucking in too much water is you flameout and become a sitting duck.

[Lewist]

i am currently working on an EDF jet boat (electric ducted fan)

Intial tests have gone VERY well, but unfortunatly i dropped the boat the other day and fractured the fan mounts and thrust tube. Its an easy fix but i will hold fire on photos and more information until it is fixed.

My hull is an ultra light shallow V hull (i may make a hydo soon) made from balsa and glassed with very light cloth. the hull weighed in at about 50 grams (its not big!) it then runs on a wattage power fan running a regular brushed motor and a 10 cell KAN1050 pack. the fan sits recessed into the hull with the thrust tube penatrating the transom at water level when the boat is at rest. it uses an air rudder to steer. this works well by itself.. the auw of the boat is about 350 grams with about 350 grams of static thrust. it scoots pritty well. But what i have done is added wings to ether side of the hull with outriggers (the boat is quite top heavy and prone to falling over in a bit of a breaze) to stablize the boat but the wing also gain aerodynamic lift lifting the hull clear of the water. when up at full speed the hull is basicly totaly clear of the water and it runs on the small outriggers and aero lift.

In the early runs i had the CofG too far forward so it was limiting the speed that the boat could acheive, however once i get it fixed i will move the fan a little more aft to get the cofg correct and she should be flying (quirte litterally!)

the boat should be capable of speeds between 30 and 40 mph (that is with a £8.00 brushed motor and and £15 pack of cells!!!!!!!!!)

with a brushless motor the sky is the limit!

i also am going to add "elevators" to the rear of the wings so that fine turing can be done on the go from the 3rd chanel on my TX!

I will post something soo..

PS it doesn't mind water ingestion either! just makes a cool noise!

[talonxracer]

The full size AV-8B Harrier uses water injection to cool the rolls-royce turbine while in a verticle ascent or descent. I would assume that a small amount of spray would not hurt a hobby sized turbine, but a full dunking or continued injestion of a rooster tail would cause at the least a flame-out. The blades on the impellers could see some deformation from the sudden pressure from the waters inability to be compressed. Alot of shock would be present, and that would be transmitted throughout the turbine, turbine mounts and the boat structure as well. Could cause alot of problems with whatever gearbox used to transmitt power to the prop as well. Lotsa drawbacks to consider, but it would sound cool as heck!

Doug

[hookpilot]

I flew CH-47 Chinooks for 24 years and performed many running water landings. On two occassions, we nearly flamed out one of the engines (Lycoming 3750hp turbines) from water ingestion. Water entering the engine as rain, fine mist is not a problem. Slugs of water are a big problem and can cause damage to the compressor section. Given the small size of a micro-turbine I'd also think that a good slug of water could rapidly cool the engine and cause warping. Maybe some sort of deflector like on the big boats might break up a wave or solid sheet of water and prevent a flame-out/damage. Just my $0.02 worth based on flirting with this for real. BTW, one of our guys did flame out an engine doing a running landing at max sink-rate, max speed. If you want to see the kind of spray we normally encountered, visit my website and see us put a Chinook in a freshwater lake at max sink speed and forward speed. Pretty impressive. Impact with the water usually locked the inertia-reels on our shoulder harnesses.

Mike
http://homepage.mac.com/hookpilot/PersonalPage.html

go to 'Flying 2" and see the fourth photo in left column. For size comparison, the rotor systems measure 100 feet from front to back, landing weight- 32,000 lbs on the lake - speed 35 Kts, vertical speed- ~200FPM down. (It's the Army's most expensive boat - $22 million)