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Stirling Cycle Water Purifier

Solar energized sterling cycle heat pump water purifier.
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This will be hard to explain. You might want to try to draw it. Think of a cylinder with a piston inside, oriented vertically for discussion purposes, closed at both ends so that movement of the piston can pressurize both sides. The piston is attached to a motor to move it up and down.

On the left side for discussion: A tube coming out the bottom goes to a regenerator at the bottom. At the top of the regenerator is a manifold. One outlet from the regenerator goes into the upper part of the cylinder. Another outlet goes through a small heat exchanger set up as a target for a solar tracking fennel lens. The exit of this solar collector goes into the top part of the cylinder. On the upstroke of the piston, the manifold directs gas from the cylinder straight to the regenerator. On the down stroke, the manifold directs the gas through the solar target.

So far this is essentially a sterling engine, however instead of a power cylinder there is a tube coming out of the hot side that goes into a heat exchange condenser trough a valve. The condenser is submerged in fluid in the bottom half of a box (call it the evaporator). The gas flowing through the condenser then goes through a pressure reduction device, extracting energy in the process, and the exhaust gas is blown into the evaporator. A tube connects the evaporator to the bottom of the cylinder through a valve. On the upstroke the condenser valve is closed and the evaporator valve is opened. The opposite occurs on the down stroke.

The whole device can be insulated to reduce heat loss.

Theory of operation: 1: On the down stroke, gas is pushed through the regenerator to extract heat from it, and then is heated in the solar collector. This causes it to try to expand and increases the pressure in the system. Some of the gas is pushed into the condenser where the increased pressure causes pressure induced condensation. The heat of condensation is transferred to the evaporator fluid. Condensate flows to a drain, essentially a vertical tube with a fishing float that can pull up a needle valve when the fluid is high enough. 2: On the upstroke, gas is pushed through the regenerator to give heat to it, this causes the gas to contract, lowering the pressure and pulling gas from the evaporator into the cylinder. This gas is replaced by gas from the pressure reduction device and evaporation of the fluid. The energy extracted from the pressure reduction device can be injected into the evaporator fluid by stirring it.

Note the energy collected from the solar collector is pumped into the evaporator several times in the recycling of heat of condensation. The “at cost” energy input is the energy needed to move the piston back and forth. This consists of friction on the piston and air resistance going through the regenerator.

cjacks, Oct 12 2005

US Pat Applcn 20040159536 http://appft1.uspto...=stirling+AND+kamen
some more here [ConsulFlaminicus, Oct 12 2005]


       Wouldn't the best place, for the energy extraction, be before the condensor instead of after it, and improving the heat removal in the condensor instead of relying on compression?   

       Methinks you will get few to understand this unless a drawing is submitted. I don't follow your comment //the energy collected from the solar collector is pumped into the evaporator several times in the recycling of heat of condensation//.
My drawing sketch shows the evaporator is open to air with an outflow pipe from the pressure reduction device pumping condensed gas into it.
Ling, Oct 12 2005

       sp: Stirling   

       Some guy was apparently on US 60 minutes with this recently? [link] to patent.
ConsulFlaminicus, Oct 12 2005

       The theory is that the increased pressure in the condenser causes condensation at a lower temperature than the fluid in the evaporator. The latent heat is thus transferred to the fluid in the evaporator. The lower pressure in the evaporator enhances evaporation taking up the latent heat to be circulated back to the condenser. The whole device is insulated and heats up, as it does so the partial pressure of the gas that is water vapor increases, increasing the ratio of latent to sensible heat, increasing efficiency.
cjacks, Oct 13 2005


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