1)ENERGY: In a typical modern electric utility plant, nearly two thirds of the energy in fuel is discarded in the form of waste heat, on top of which there are significant transmission line losses. So an energy conversion efficiency of about 34 percent is fairly typical of a modern conventional powerplant. Older plants are even worse.
NEW TECHNOLOGIES: Micro-turbine generators are said to be as much as 50 percent efficient, and micro-turbine sales jumped to 1,200 units last year, from 300 the year before. Drawbacks are high capitol cost per kilowatt, and they can only run on a very limited range of fuels.
The ramjet generator (see ramgen.com) now in the development stage at Ramgen Power Systems Inc. is anticipated to be as high as 67 percent efficient, and it can run on a variety of fuels. Its primary drawback is once again capitol costs, due perhaps in large part because typical ramjets must be run at supersonic speeds in order to be fuel efficient, and spinning a disk at supersonic speeds for thousands of hours is no small engineering feat. However, if Ramgen can pull it off, this could be an important new energy technology, and we wish Ramgen all the best.
THE BLASTWAVE JET CO. APPROACH:
Part of our propulsion system (prime mover) is an innovative variant of the
Pulse Reactor valveless pulsejet that was developed in the Advanced Research
Division of Hiller aircraft under Senior Research Project Engineer Ray Lockwood,
(about whom it was noted in the book ‘Vertical Challenge The Hiller Aircraft
Story' by Jay P. Spencer) "Probably understood more about unsteady flow
than anybody else in the United States." and the U.S. led the world in
this technology.
The bottom line is that with Blastwave Jet engines we can produce a sub-sonic tipjet rotor-powered electric generator that is safe, really cheap and simple, and uses off the shelf components.
The basic engine is very clean-burning and efficient, but there are a few design parameters to keep in mind. One is that while a relatively compact unit size is appealing, the mechanical advantage (and so efficiency) increases with increased rotor diameter.
And to create a truly efficient system that is well into the 90 percent range, it is necessary to use engine heat for space and water heating, and to use that same heat to drive ‘gas absorption cycle' chillers for air conditioning.
Lastly, at the Sandia National Lab(Livermore, CA April 27 1988) pulse combustion
workshop, our new friend, visiting scientist Kazuo Saito from Toshiba Corp.
of Japan asked the following important question: Where do you put this district,
or neighborhood utility system?
For crowded Japan, there was only one answer: under the street. It should be
no more difficult than putting in a septic tank. Perhaps less so. This would
work in the U.S., too.
THE BOTTOM LINE: Aside from major profits, incentives include using the ‘excess'
heat from electric power production to heat and cool our homes and commercial
buildings, which in turn lessens global warming, (dramatically reducing carbon
dioxide, sulfur dioxide and nitrogen oxide ‘greenhouse' gasses), improves
on our trade imbalance, and helps preserve finite global resources for the next
generations of people around the world.
THE BLASTWAVE SR (SUPERSONIC RAMJET)
The basic ramjet is kind of like lighting a firecracker in the middle (or end)
of a tube. The blast goes out of either end, and not much changes unless the
ramjet is moving at high subsonic, or supersonic speeds.
The Blastwave Supersonic Ramjet concept is different in that it employs a re-entrant 'bourda' inlet, a central reflector cone, and a series of internal reflector surfaces that act as a one-way aero valve. This keeps the flow direction always moving from inlet to outlet. Internal detonation waves are channeled out the exhaust, with no chance to move upstream. The trick is to be able to do this without the substantial cold-drag penalty associated with the conventional ramjet flame-holder, which combusts at sub-sonic speeds. The scramjet, on the other hand, combusts at supersonic speeds. Keeping the fire lit is the challenge there.
The Blastwave Supersonic Ramjet concept is different in that only a portion of low is subsonic, but this hot fuel-rich core thoroughly mixes with and ignites the lean-burn supersonic flow.
Other unique characteristics include a built-in ceramic VPJ (valveless pulsejet) which acts as both diffuser and igniter. It only produces about 40 pounds of thrust, but provides sufficient airflow to initiate subsonic ramjet operation. Externally, it looks like a streamlined football, and it is quite compact for a 40 pound valveless pulsejet. Also under study is an external co-flow shroud design that induces cylindrical airflow to increase mass flow and decrease velocity, for noise control.
The bottom line is that if we can build this engine, then we will have a jet that costs only a fraction of what it takes to build a turbojet, and perhaps more importantly, the Blastwave SR (Supersonic Ramjet) could be operated on fuels that cost a fraction of what is required to run a turbojet.
As to the question of whether or not an engine such as we've just described is even feasible, only time (and a lot of work) will tell.
As to the jet electric power generator concepts previously discussed, I am absolutely certain that it can be done with technology that exists today, and would go a long way toward building a better tomorrow.
-Ed Lockwood