A Stirling engine uses nothing more than heat to produce stirling energyA Stirling engine uses nothing more than heat to produce really cool energy. The fuel could be solar energy, waste industrial heat, cryogenics temperatures, a biomass furnace, geothermal heat,.. Basically, fuel is not critical; it'll run on anything that produces heat. Unfortunately, many think of a stirling engine as small toy like mechanism fascinating observers as it clinks along, its small size looking as though it could do no more useful work than to entertain its owner. If you've watched any of the dozens of stirling gizmo video's on you-tube, you probably came away with the impression that they were only toys. Not so; take a look at what a thermo stirling engine can do with a little sun shine. This is not a toy. A Stirling engine is an external combustion heat engine, that is, where the internal working gas or fluid is heated by an external source. The engine then converts this thermal energy to mechanical energy. By their very design, every heat engine must have a hot side and a cold side. The greater the temperature differences between the sides, the greater the potential for cyclic efficiency.
In the real world, the cold side of a heat engine must remain at close to its surrounding ambient temperature, but no lower than -300°F. Obviously, to reach thermal absolute zero (0 K) would be a historical achievement. The lowest recorded temperature was only -273.14999999955° C, wow!. In any event, improving stirling technology involves increasing source temperatures to achieve thermodynamic efficiencies. Obviously, the temperature's upper limit is restricted only by the material's limitations. To get an idea of the theoretical efficiency of a system, take the difference between the hot and the cold end and divide that by hot ends temperature. Of course, absolute efficiency is unachievable. Let's look at how they work. Some say, stirling engines are hard to understand. Not so! a simple example of the hot cold thing will help you understand the forces at work in these engine. Once you grasp this, you'll pretty much know how stirling engines work. Okay, do this: inflate a toy balloon, seal it, and put it in a refrigerator. What happens next? It begins to contract. Now remove it; the cold air begines to warm up and the balloon expands, the air inside just reacted to external influences; expanding and contracting. If this cycle could repeat itself fast enough, couldn't this energy be used to drive a mechanical device? See - easy.
Okay, instead of a balloon, visualize a glass tube - a sealed cylinder, within which a piston resides. The piston is permitted to move freely back and forth. Now apply heat to one end of the tube and the expanded heated medium (air or gas) drives the piston to the opposite (cold) end. Why? Because when a sealed in medium is heated, its pressure rises and work is preformed. Next, the medium begins to cool, the pressure is reduced and the piston returns. Simple! There are two Stirling heat engine categories; the power piston and the displacer type. The best way to picture these is to see animated examples of them at work. Click this animated engine link; then select Stirling to see of both types. Alpha Type Stirling engines contains one hot and one cold power piston. The high temperature heat exchanger encloses the hot cylinder/piston, while the low temperature exchanger encloses the cold cylinder/piston. Refer to the animated engines. Beta Type Stirling engines are single power piston engines. They are arranged on the same shaft as the displacer piston. A special-function the displacer piston is designed to move the working gas back and forth between the hot and cold heat exchangers.
Gamma Type Stirling device is a Bata engine. The power piston is attached in a separate cylinder alongside the displacer cylinder, although it is still connected to the same flywheel.
Power pistons change the volume between the working space and atmosphere. This piston provides the power. Displacers move the working gas from the hot area to the cold area. It has no effect on the engines volume. Something should be said about the contents of the engine; i.e., the internal gas or fluid that performs the actual work. The working gas can be air, helium, hydrogen, and others all of which are inexpensive and readily available.
Because a Stirling engine is an external combustion device, it has high thermal efficiency, multi-fuel capabilities and low pollution output. Hence it has the potential of becoming a major source of power.
Keep an eye on heat engine technology. Stirling energy, promises technological alternative energy advances for the near future. A Stirling engine is a unique device... thanks for stopping by  Custom Search
|
