> Mr. Lamar,
>
>
> I have read with interest the articles about turbo compounding. I am not
> an engineer but I have served in the US Navy as a Machinists Mate and
> worked for many years as an automotive mechanic. Somewhat of a gear
> head, I guess. While I spent only 3 years in the USN, their ?A? school
> for the rate, and my service at sea made quite an impression. It has
> always made me wonder about the amount of energy wasted by current
> automotive technology. When I was active, most propulsion was by high
> pressure steam but its efficiency was quite remarkable.
>
>
> A basic steam cycle started with pure, de-oxygenated water that was
> pumped at around 1600 PSI into a boiler. What came out the other end was
> 1200 PSI dry steam at around 900°F. It was then routed through a nozzle
> block to a high pressure, steam turbine where a great deal of the heat
> energy was converted to rotary, mechanical energy. The exhaust of that
> turbine was then directed to a low pressure turbine where additional
> heat energy was converted and the resultant exhaust (that at this point
> was basically saturated steam under a partial vacuum and at about 70°F)
> was collected in the main engine condenser where it was pumped through
> another heat exchanger located in the boiler exhaust stack to allow the
> condensate to be preheated before returning to the feed pumps where the
> whole cycle started over. 1200 PSI of pressure and more importantly,
> 800°F+ of heat removed. From a 6 inch steam line we generated around
> 40,000 Hp at the screw if my memory serves. (Please remember this is a
> REALLY simplified description)
>
> In and internal combustion application, chemical energy is again used to
> create heat energy that in turn is converted to mechanical energy for
> use in our transportation systems. Along the way, MOST of the heat
> generated (the actual energy, the ?good stuff?) is wasted by radiating
> heat from the engine surfaces, radiators, condensers, exhaust and now
> catalytic converters. I have always wondered why there is not a great
> deal of focus on the capture and use of this energy!?
>
> In the compound engine, an attempt is being made to finally do this and
> it seems like a step in the right direction. My question is this. Why
> stop at a single turbine wheel? Outside of weight and space, which may
> be more than compensated for by the extra mechanical energy generated,
> what keeps us from exploring something like a multi-stage turbine being
> developed to convert some of the currently wasted energy? I would prefer
> this not be long winded. Are you aware of any experimentation in this
> area?? It would seem that the exhaust temps on the Wankel rotaries would
> be an ideal source of energy to boost efficiency.
>
> Anyway, enough rambling, I really like your website. It is extremely
> informative. I have a dream to built a rotary powered kit some day, but
> I also have a wife that has a dream of a closet full of nice clothes?..
>
> Merle Zingg
>
> If I could get the first turbine to fly again I could die a happy man.
> I don't understand why the entire world does not understand what you just
> described.
>
> Rumor has that Boeing is working on it for UAV use. Mazda should be
working
> on it all out as the rotary is uniquely suited to turbo compounding
> as it has no exhaust valves which were the Achilles heal of the early
> 1950's turbo compound engines. It should be Mazda's highest priority
> as it holds the potential of reducing the world wide automotive fuel
consumption
> by 5% or more. Lots more in the case of aircraft engines. The amount
of money saved by
> this technology world wide is many MANY orders of magnitude more than
what
> it would cost to develop.
>
> Wives they can be hand brakes sometimes. There is no question about it.
> --
> Paul Lamar ...No rotor no motor.
>
Mr. Lamar, on his website, wrote:
"The power in the Mazda Wankel rotary engine exhaust has been talking to
us for 30 years. It has been saying. 'Hook me to turbine, hook me to a
turbine, hook me to a turbine.'"
Merle Zingg wrote:
"Why stop at a single turbine wheel? Outside of weight and space, which
maybe more than compensated for by the extra mechanical energy
generated, what keeps us from exploring something like a multi-stage
turbine being developed to convert some of the currently wasted energy?"
Yet, in the turbocompounding thread here on the AREN Newsletter, Mr.
Lamar warns us that developing turbocompounding will take millions of
dollars.
So, since I am new here, fired with passion for turbocompounded rotaries
and unencumbered by an engineer's caution, asking, "what if we took the
results of other peoples' spending millions of dollars and apply it to
the turbocompounder?"
Specifically, what if we used the turbine sections of the small jet
engines used for Very Light Jets (VLJ's)? Specifically, the turbine
sections of the Williams FJ33 or the Pratt & Whitney PW600 series?
Here is a an outline of the exterior of the Williams FJ33:
http://s12.photobucket.com/albums/a234/JacobPotts/Atom/Turbocompound/?action=view¤t=Williams_FJ33_Engine_001.jpg
<http://s12.photobucket.com/albums/a234/JacobPotts/Atom/Turbocompound/?action=view¤t=Williams_FJ33_Engine_001.jpg>
Here is a cutaway of the Pratt & Whitney PW625:
http://s12.photobucket.com/albums/a234/JacobPotts/Atom/Turbocompound/?action=view¤t=PW625_Cutaway_002.jpg
<http://s12.photobucket.com/albums/a234/JacobPotts/Atom/Turbocompound/?action=view¤t=PW625_Cutaway_002.jpg>
Here is a closeup of the PW625 turbine section, behind the combustor:
http://s12.photobucket.com/albums/a234/JacobPotts/Atom/Turbocompound/?action=view¤t=PW625_Cutaway_001.jpg
<http://s12.photobucket.com/albums/a234/JacobPotts/Atom/Turbocompound/?action=view¤t=PW625_Cutaway_001.jpg>
Now, why in the world do I make such an outlandish suggestion?
1. Mr. Lamar, in the AREN website, has already adapted an existing
design, an automotive supercharger, for a "single-stage"
turbocompounder. I am following his example of adapting existing
structures to new uses.
2. Williams and Pratt & Whitney have already spent the millions of R&D
money that none of us have, to make a multistage turbine, out of
material that already can withstand the high temperatures and transonic
velocities of a rotary engine's exhaust.
Suggestion 1:
Position the turbine section of the VLJ engine of your choice right
outside the P-Port exhausts of the rotary, at a right angle to the
e-shaft of the rotary. The exhaust from the first P-Port would hit one
side of the turbine, and that from the second P-Port would hit the
opposite side. That way, the maximum energy from the rotary will blast
straight onto the turbine blades.
Suggestion 2:
Transmit the power recovered by the turbine to the prop(s) by either
mechanical or hydraulic means.
Doubtless my suggestion is riddled with problems, so critique away!
If there are better existing turbine assemblies, suggest away!
Sincerely,
Les Nordman :-)
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