Hybrid Ship Pulse Detonation Turbine to DC Electrics

Hello Folks from Boat Design

This is SeaBird, and it has been along time since I was last here. Ok couple of quick updates;

1) New updated website with tonnes of new data and pictures. please have a look at www.seabirdadventure.com

2) Actually have a working 125KW prototype in test runs now, whew. Will be posting video footage and all kinds of new data very soon.

3) Still using waste oils but using 90% H2O2 as the oxidizer for both pre-fuel heat and detonation oxidation of the waste oil.

4) Due to the combustion temperatures hitting 5900F, sigh, needing to rebuild the turbine elements using poly-alloys:idea:.

Well that's all for now, been a long time.

Cheers, SeaBird

 

I've got six gallons of used engine oil if you want it.

 

Good luck....

Most Tesla turbines have an efficiency of about 60% where a good conventional turbine can be close to 90% or greater, depending on size. There are other practical problems with the Tesla concept, the first being that the rotating speed of the turbine is limited by the shape of the disks. When a disk is of a constant thickness you can't spin it very fast. Moreover, a Tesla turbine has the highest temperature at the outer rim of the disk and this induces high stress in the disk bore. If you are using the machine as a compressor it isn't as bad, but as a turbine, the higher temperatures are a problem. Warpage of the disks after shutdown is common problem with the Tesla concept. Very high speed is necessary to achieve high efficiency in a Tesla machine, but the basic geometry precludes that.

As to pulse detonation, Pratt & Whitney and GE are being funded to the tune of multiple millions to develop the concept and there are inherent problems having to do with combustion stability and problems with part power operation that are being found. DARPA has spent a bundle on the technology an seems to be cooling on the concept.

What you are doing all sounds good but if you want to power a boat efficiently you would do well to find a more mature technology and develop that as opposed to starting from zero.

 

Hello Mark, and Thank you

Right now I've got several hundred gallons of waste oil so I'm all good there right now, but thank you for the offer.

Cheers

 

Hello Yellowjacket, your points are well thought out

The Tesla design seems to be working quite well, at this point I'm using 440 stainless, highly polished laser cut disk platters with all the inner platter pieces cut from the same material to minimize thickness variances.

On the speed issue I've got 17.75" platters you can see these on http://www.seabirdadventure.com/photos/category/17-pictures-of-the-tesla-turbine that are spinning at a constant speed of 7254 rpms which through a 4.03:1 transmission give a reduced rotation of 1800 rpms for the 125KW AC generator.

Though this is relatively high rotational speed for the disk pack that weighs 168lbs it does not cause over-stress on the materials.

The best way I solved the platter warpage problem is to use multiple compression bolts, also hi-grade stainless, that are used to compress the pack by using a specific lbs torque and a torque pattern during assembly.

On the PDE, well I haven't spent 100's of millions but have had some early and "preliminary" success with the initial prototypes that I have built. My plan is to publish the video on this work on this Youtube channel http://www.youtube.com/user/seabirdadventure The video has been shot but I need to now get it edited and then will publish here.

My goal is to 1st push the Tesla Turbine efficiency as far as I can take it and I may still use a impulse or reaction turbine later on but due to the impulse gasses I'm producing I still believe that the laminar method will be best. On the current prototype the reactor gases are moving at 1200m/s when they impact the blades, strength is an issue.

Cheers, SeaBird

PS thank you again for your interest.

 

Good god, 90% H2O2 is way up there on the list of things I would never want on a boat! How are you keeping it contained?

Wouldn't red fuming nitric acid be safer?

What's the spacing between the plates on your turbine?

 

Some nice information on your site.

More links on the aircraft topics:

http://en.wikipedia.org/wiki/DARPA_Falcon_Project


http://en.wikipedia.org/wiki/Pulse_detonation_engine

I'm not sure what that is.

Googled it.

Hydrogen peroxide
http://www.ehow.com/list_6187449_effects-heating-h2o2-stability.html

 

Hello Cthippo and kach221

Thank you for your questions, Actually 90% H2O2 is not as bad as the press says if you are careful with it, where as re fuming nitric acid is truly nasty stuff which many years ago I accidentally generated due to the retort getting out of temperature range.

But back to the H2O2 questions, I am using high grade stainless steel line fittings and tanks with nitrogen tanks for pressure. As long as you do not get metal impurities into the H2O2 it is really quite safe.

H2O2 does catalyze in quite a spectacular way when metals such as Ag are added to it and yes if you start a reaction you had better have the correct pressure relief and heat dissipation equipment set up. See http://www.seabirdadventure.com/tes...e-archives/earth-friendly-forms-of-propulsion

However even if the H2O2 goes into a runaway reaction it only generates pressure and steam no flame, second however though, the steam is 975F so who needs flame

Cheers, Seabird

 

On the other hand, RFNA won't explode spontaneously like H2O2 will. You don't need a relief valve, more like a blowout disc.

Oh yeah, and whatever you do, don't get any on you!

 

WOW!!! and people give me grief for talking about propane.

Glad to see your work and wish for you the best success, I carry the Tesla Turbine banner every chance I get. I think it has great potential on the cold side of things.
Will stay tuned in to your website.

Thanks
Ron

 

Hello again to cthippo and Ronl

comment on the RFNA, which stands for "Run Fast Nasty Acid", it does go boom when combined with glycerol at higher than 24F and then the acid gets on everything.

But in all seriousness the H2O2 is not all the bad, initially I had the special suit, gloves mask, shields etc. But after working with it for a few months I started getting a little lazy and didn't use my gloves, always you my mask though, and got a little on my fingers. Initially I freaked out as my fingers turned white and I mean, Titanium Dioxide white, but it turns out that a little actually caused no permanent damage and after a few hours everything was all good again.

Now this does not mean anyone should do this, I'm just lazy.

I got 3 video shorts on film, not finished, that will show all this. So soon you'll all be able to watch this.

Cheers, SeaBird

 

I didn't quite follow what you were saying on your website. Is the Tesla turbine feeding air to the PDE or converting the output of the PDE to mechanical energy? How are you going to cool the PDE?

 

Hello cthippo, I'll try to answer...

When I started building the PDE Turbine I needed the fuel "waste oil", oxidizer "H2O2 exhaust", pressure "from catalyzing chamber and ignition "Plasma injector".

I run the 2H2O2 through a catalyzing chamber to break it down into 2H2O "in the form of steam" and O2 "pure Oxygen". This reaction yields a great deal of heat and pressure, 790F, 1200m/s respectively.

The heat is used to preheat the waste oil, the pressure, steam and O2 is all used to premix and charge the PDE tube and create a detonation in the form of a pulse, the pulse in turn spins the Tesla Turbine and additionally causes a vacuum in the PDE tube thereby drawing in the next pulse of gasses for detonation.

So first answer is the PDE output drives the Tesla Turbine. Second answer, primary through duty cycle, the lower the duty cycle of the PDE the more time it has to settle out the heat, in addition the output from the catalyzer is about 5000F cooler then the PDE device, so all the input gasses help to cool the device also.

Cheers, SeaBird

 

Hello cthippo, Few pictures for you on the H2O2 50%

Here is some of the testing done with the 50% H2O2, the testing with the 90% was all on video so when that gets done I'll post this also.

I will try to re-do some of the tests seen here and on the web site at http://www.seabirdadventure.com/photos/category/23-hydrogen-peroxide-testing
for the 90% as soon as I can with photos for you folks to see the difference between the 50% and the 90%. :idea:

Cheers, SeaBird

 

Hello Kay9, Thought I'd show you some picture updates

:?:

I think you mean see anything on the turbine? If so here are some, updated and some older, pictures of the 125KW prototype that is currently built and being tested. These pictures are shown with the 50% H2O2 running, I will be posting some new ones with the system running on 90% H2O2, here is the link

http://www.seabirdadventure.com/photos/category/17-pictures-of-the-tesla-turbine

Let me know what you guys think, cheers SeaBird