10 kW Ringbom-Stirling with generator for sale

[Aviator168]

http://cgi.ebay.com/10-kW-Ringbom-Stirl ... 2a0eaa595f

[vile_fly]

Working gas = Helium
Power piston = 130mm (5.10") bore
Displacer piston = 133mm (5.25") bore
Stroke = 31mm (1.22") for both
Swept volume = 407cc (24.8 cu. in.)
working gas temp-hot = 750 deg. C (1382 deg. F)
Displacer stroke control via interactively modulated variable damper gas spring
(stepper motor controlled needle valve)
Mean working pressure = 7 MPa (1016 psig)

Regenerator: sintered wire fiber
wire diam. = .076mm (.003")
porosity = 76%
material = 316 stainless steel wire

Shaft Power = 11.7 kW@1800rpm

[Aviator168]

Amazing. 15hp from a bit more than 400cc.

[Aviator168]

This engine is more powerful than the Lycoming O-540 per unit displacement

http://en.wikipedia.org/wiki/Lycoming_O-540

Does anyone know how heavy the stirling engine is?

[vile_fly]

Here's the pictures and data on the engine. It was a screen capture, so don't expect quality.

[vile_fly]

some more.....

[vile_fly]

some data.

[vile_fly]

more data.

[vile_fly]

"This machine is a propane gas-fired 10 kW Ringbom-Stirling engine powered electric generator. The first Ringbom-Stirling engine was first patented by Ossian Ringbom in 1908. The configuration is essentially a Stirling engine that has a free-piston displacer piston and a kinematic power piston. This machine is a modern embodiment of the original concept. It was designed, built and tested by me in 1988-1989 with the consultation and support of several other seasoned, experienced and well published Stirling colleagues including Dr. James Senft, (University of Wisconsin), David Gedeon (Gedeon & Associates), David Berchowitz (Global Cooling, Inc), Ken Cohen (Combustion System Consultant), Jon Scull (Designer), and Souran Monechehri (Stevens Institute) under a $985K DARPA contract with the US Navy."

" One of its many innovative design features is the Displacer Control Module (DCM), configured to be quickly removable from the engine via the removal of a single 7” expandable retaining ring (Snap ring tool included!). This provides access to all of the upper end components for service or complete & rapid replacement of the entire DCM for minimization of down time during service of the DCM. Another novel design feature lies in its novel control system designed to enable the engine to self-regulate its electrical power output in response to the demanded electrical load being demanded. This is accomplished with a stepper motor driven needle valve that varies the damping characteristics of the displacer piston in response to changes in electrical load induced speed changes of the crankshaft. The design details are set forth and explained in two technical papers published and presented at the 1988 & 1989 Intersociety Energy Conversion Engineering Conferences (papers available from them). Part of the development program also included the design and development of solid lubricated hybrid ceramic bearings. Pictures 7-12 include technical information but the uploading process has taken them out of sequence."

"The lower drive unit, consisting of the power piston, four-bar linkage, crankshaft and electric alternator was designed to eventually be housed in a lightweight composite cylinder pressure vessel but is currently housed in a high strength steel cylinder.

At the end of the 2-year development program in 1989, testing of the machine was not fully completed (as is often the case!). The engine was delivered to the Navy and subsequently purchased back in 1992 with the intention of completing its development. That was 19 years ago and due to other work, the machine has been stored untouched in my shop. It is for that reason that the decision has been made to offer it up for sale."

At the time that the funding was exhausted and the machine delivered to the Navy, it had been successfully run in reverse mode (motoring the engine with the alternator running as an electric motor) as a cryogenic cooler. This is the conventional means of proving out Stirling engine thermodynamics, kinematics and gas dynamics. A photo of the expansion space heat exchanger (the engine heater head) is shown at minus 101.2 0 F illustrating the machine’s cooling capability. The next phase of testing as a heat engine was not yet performed.

The 10 kW electric alternator is an ultra-high efficiency electronically commutated, permanent magnet brushless DC device from UQM Technologies (UQM.com). It also serves as the starter motor.
Total shipping weight estimate is ~500-700#. The engine is located in Parishville in northern NYS (13672). Batteries (six 12V automotive) not included! Steel frame is ~ 2' X 4'.

[Aviator168]

Is my calculation correct?

Heater: Finned tube. 2 pass
No. of tubes per circle 44
Tube ID 3.86 mm
Tube length (2 rows) 280 mm

Total heater exchanger area (gas side) 44 * 3.86 * pi * 280 * 2 = 298646.656 mm^2 = 2986.46656 cm^2

This is every large area for one cylinder.

[markombi]

Very, very interesting

[skunkworks]

I wonder if the 10kw rating is strictly the alternator rating. I wonder if they ever generated 10kw from the 400cc engine. Seems a stretch.

asm

[Aviator168]

Why not. Do the heat transfer math yourself.

[Ian S C]

According to the info,the shaft power is 11.7Kw, the generator is 95% efficient, the motor uses 900 W driving fans pumps and controls, sounds about right. Ian S C

[seanx]

I also have to buy a 5kW generator. Does anyone have?