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Sunray Diversion Thermal Engine

Divert sunrays to create a changing difference of temperatures
 
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[Edited for clarity (I hope)] 1. At least two insulated compartments serve as the expansion/compression chambers. Preferably these will be transparent.
2. In each chamber there is some coolant (say the safest Freon alternative).
3. Each chamber has controlled valves to stop or enable gas flow between the chambers.
4.a The chamber is heated by concentrating sunlight. 4.b. For catching the light and transfering it to heat - (i) If the chamber is transparent, then inside there is a dark colored material (i.e. a metal sheet, or smoke particles)
(ii) if the chamber is not transparent then the light is concentrated on an external section which is dark colored, and which is not insulated, so that the gas inside heats up.
5. For cooling,
(i) either via cooling fins when sun is not concentrated on the chamber and fins (this is the simplest)
(ii) or via heat-bridge which is electrically connected during the cooling phase but disconnected during heat phase
(iii) or via a coolant sent into the chamber during the cooling period.
6. The alternating heating and cooling cause the gas inside to alternatively compress and expand or to alternatively liquify and evaporate.
7. The pressure changes in the chamber move a piston.

It is like a "flame eater" engine, but instead of hot flame alternatively entering the chamber or cool air entering it, this motor uses the concentrated sun rays alternatively being focused on different sections of the engine, in order to create the movement.

The concentrated sunrays (with Fresnel or hyperbolic mirrors or using clear plastic tubes filled with water used as "magnifying glasses", or whatever other idea is used to concentrate the sunlight) are alternated to switch the phase of the chamber from heating to cooling. When the sunrays are focused into the chamber, (and on its cooling fins) it heats the gas inside. The rays are then deflected to the other chamber, while this chamber cools (or is actively cooled).

Possibly cooling elements of various sources could be "sent in" during the "compression" cycle, and it would still be worth the output.

==============================

An even more interesting motor of this sort could be a section of pipe with several one way air pressure valves. Heating up the sections in succession would cause a continued flow of gas - with air being the easiest

(In a way, this would be analog to linear electric dc motors).

==============================

Going even further - Perhaps making the compartments alternating phase in quick succession, would create perhaps an "AC" motor of gas. (of course this is only an analogy - it would be gas flow and not electric current, but perhaps this can be done at an ultrasonic level, and with ionized gas, would directly create an alternate electric current ...)

pashute, Jan 24 2011

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       /deseminate / What you do with a seminal idea?
bungston, Jan 24 2011
  

       /deseminate/ Or perhaps what happens to the hyperbolic?
bungston, Jan 24 2011
  

       it's like you are trying to invent a whole new culture of technology complete with new terminology and new basic principals. possibly the wording of this idea was translated somehow. An "AC motor of gas" is at best a mixed metaphor.
WcW, Jan 24 2011
  

       Don't underestimate the power of a Metaphor ...
8th of 7, Jan 24 2011
  

       Ooh, Metaphor power. Now we're talking.
There'll be Metaphor-powered cars next...
neutrinos_shadow, Jan 24 2011
  

       I'm not entirely sure I've understood the idea, but if I have, it's the coke can motor.
marklar, Jan 25 2011
  

       edited for clarity (I hope).   

       desemination deseminated.   

       What's "the coke can motor""? (I see only Stirling engines in a coke can - almost nothing to do with this idea)
pashute, Jan 25 2011
  

       Already baked. Look up "striling engine". There is also a very recent version developed for the purpose of solar energy, it uses a collector dish to concentrate light to the engine. Looks like a sat dish with an engine instead of receiver at the focal point. The engine itself is packed with extremely high pressure gas to maximize effects. It's been a year or two since reading about the project, they may have statistical data by now.
AutoMcDonough, Jan 25 2011
  

       I would think that a small reflector that was geared in time to the cylinders would allow the engine to be "in time" which would also allow an efficient stationary collection system. The addition of a centrifugal system of timing modification would make the engine efficient in a wider window of speeds. There is the need for a substantial heat sink, the ocean, or a geothermal sink of some sort. Using ambient air is going to greatly reduce efficiency and total output in the kind of conditions where a motor of this sort is going to be worth its salt.
WcW, Jan 25 2011
  

       Having not read the idea (honesty is my vice), I may have missed this. But, if this were developed on a trans-national basis, the enture solar-refocussing issue would be solved.
MaxwellBuchanan, Jan 25 2011
  

       Max please read the idea! I believe it is worth a serious discussion!   

       WcW - why so? Solar towers have been built around the world, one near my parents at the Weitzman Institute is said to give very good results. They use various types of Stirling and other heat engines.   

       Theoretically there is almost 1kW of power in 1 square meter on a clear day. That's not something to be pushed aside.   

       The Stirling moves the air with a displacer from the heat accepting location to the heat dissipating location, using inertia of the movement caused by the original expansion of AIR from heat. In this idea, instead I move the source of heat altogether. Since it is concentrated sunlight, a very tiny movement (of a mirror) is enough to remove the heat and divert it to the next cylinder. Shouldn't take much more energy than was being put into the Stirling for displacing the air to the cooling area. Should it? Why can't we have an intelligent discussion here?
pashute, Jan 30 2011
  

       Alternating where the 'hot' part is takes up a lot of energy because of the heat capacity of the surrounding material.   

       This might work well on a small scale with glass chambers and thick black smoke as a working fluid though. But it would be less efficient the bigger it was.
mitxela, Jan 30 2011
  

       You have a black substance that looses heat to its surroundings quickly (copper painted black). It gets bombarded with sunlight and quickly the whole thing heats up, gas expands and piston pushes out. None of the heat can escape without first working on the insulated air.   

       A tiny move of the mirror diverts the light to the next cylinder, and opens a gate to allow flow of heat out of insulation layer (perhaps a set of copper "switches" connecting to cooling fins.   

       Or: Even easier: This could be more like a Rankine cycle with butane. The light concentrates on the lower are boiling the butane. Pressure pushes the piston, but, JUST AS IN THE STIRLING, the gas reaches an area with cooling fins and chills down, while the light has been stopped.   

       This is not like the minto wheel, it's a steam engine using the pressure to push a piston, not the change of center of gravity.   

       [Marklar], to which coke can motor are you referring?
pashute, Jan 31 2011
  
      
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