Vamoose, with a little research I found this engine not exactly the same, but it does use expanding gas to move a piston and works as a pump.The temp is in the range of 180f so its not a rankin cycle.It does use water as a cooling agent so it is kind of like a cross between the solar rocker stirling and the drinking bird.
http://thefraserdomain.typepad.com/ener ... heat_.html
The Energy Blog
June 12, 2007
Low Level Heat Powers Low Cost Hydraulic Engine
Deluge, Inc. has developed a thermal hydraulic engine that is now ready for commercialization. The company has just successfully completed long term field testing of the technology, and has obtained patents on the design in nearly 40 industrialized countries world wide.
The Natural Energy Engine™, requires no combustion, operates virtually silently, and generates no emissions. Developed over the past 10 years, it operates by utilizing low level heat energy, 180°F (82°C) is suitable for many applications, from solar, geothermal, or any other heat source, including waste heat from existing processes.
The main components of the engine system are quite simple – a piston/cylinder and a heat transfer system. The cylinder contains a piston and a working fluid, and depending on the application may have a module to reposition the piston after each stroke. The heat transfer system comprises heat exchangers, a system to circulate the heat transfer fluid (typically water), and a simple circulation controller.
The key difference between a traditional combustion engine and the NE Engine is that the NE Engine relies on the transfer of heat to, and its subsequent removal from, a working fluid within the cylinder. As the working fluid is heated it expands, providing the pressure to drive the piston, and is subsequently cooled to complete the cycle.
“It is a thermal hydraulic engine,” says Brian Hageman, the inventor of the Natural Energy Engine. “It uses the same principles of expansion and contraction from heat as a thermometer, and uses the expansion to create powerful hydraulic pressure in a manner similar to an automobile’s brakes.”
The Company projects that engine configurations can easily be priced at 60-85% of power systems that produce equivalent output.
The NE Engine creates mechanical energy in a three step process:
Step 1: Heated water is collected – for many applications 180°F is suitable.
Step 2: The hot water enters a heat exchanger where the heat is transferred to a working fluid. The working fluid, typically liquefied CO2, has a very high coefficient of expansion, meaning that it expands and contracts significantly, based on its temperature, while remaining in a liquid state. As the working fluid is heated, it expands, pushing a piston in the engine’s cylinder.
Step 3: Cooling water – generally in the range of 100° lower than the input water, with varying differentials depending on the application – then enters the heat exchanger causing the working fluid to contract, readying the piston for another stroke.
Proof of the engine’s operating principles was first demonstrated at the U.S. Department of Energy’s Rocky Mountain Oil Testing Center in Wyoming, where a prototype engine successfully pumped crude oil from underground formations using geothermal energy as the sole source of heat for operation.
In early 2006, Deluge embarked upon extensive field testing, conducting a multi-engine long term test under varying conditions in Kansas fields, and completed well over 100,000 hours of continuous operation over more than a year. The results exceeded even Deluge’s expectations in terms of reliability, costs, and performance.
Bumpkin…