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Efficient Actuators for Alpha Stirling

Started by Bret Cahill June 22, 2017
The goal is an Stirling w/o a mechanical crank/flywheel.  Instead it'll have 2 electric actuators and a linear generator.

Supposedly a linear generator, a glorified shake light, can be 95% efficient.  I need an actuator that is pretty efficient as well.

The actuators need a to consume less than 100 watts and have a stroke of ~ 15 cm.

Since it is only for demonstration purposes it is OK if it is run off of software/USB.


Bret Cahill



On Wednesday, June 21, 2017 at 11:16:44 PM UTC-7, Bret Cahill wrote:
> The goal is an Stirling w/o a mechanical crank/flywheel. Instead it'll have 2 electric actuators and a linear generator. > > Supposedly a linear generator, a glorified shake light, can be 95% efficient. I need an actuator that is pretty efficient as well. > > The actuators need a to consume less than 100 watts and have a stroke of ~ 15 cm. > > Since it is only for demonstration purposes it is OK if it is run off of software/USB. > > > Bret Cahill
How do you propose to keep the gas sealed within the chamber? Eventual leakage of the gas from the seals is what dooms the Stirling Engine, if I recall correctly, especially if it's Hydrogen. Michael
> > The goal is an Stirling w/o a mechanical crank/flywheel. Instead it'll have 2 electric actuators and a linear generator. > > > > Supposedly a linear generator, a glorified shake light, can be 95% efficient. I need an actuator that is pretty efficient as well. > > > > The actuators need a to consume less than 100 watts and have a stroke of ~ 15 cm. > > > > Since it is only for demonstration purposes it is OK if it is run off of software/USB. > > > > > > Bret Cahill > > > How do you propose to keep the gas sealed within the chamber?
An "electric crank" allows the entire thing to be hermetically sealed. No moving parts extend out of the casing, only some wires. Same for some free piston. The biggest unsung advances in technology include servos so I'm hoping there are affordable linear actuators as well. Bret Cahill
On Sat, 24 Jun 2017 08:40:51 -0700, Bret Cahill wrote:

>> > The goal is an Stirling w/o a mechanical crank/flywheel. Instead >> > it'll have 2 electric actuators and a linear generator. >> > >> > Supposedly a linear generator, a glorified shake light, can be 95% >> > efficient. I need an actuator that is pretty efficient as well. >> > >> > The actuators need a to consume less than 100 watts and have a stroke >> > of ~ 15 cm. >> > >> > Since it is only for demonstration purposes it is OK if it is run off >> > of software/USB. >> > >> > >> > Bret Cahill >> >> >> How do you propose to keep the gas sealed within the chamber? > > An "electric crank" allows the entire thing to be hermetically sealed. > No moving parts extend out of the casing, only some wires. Same for > some free piston. > > The biggest unsung advances in technology include servos so I'm hoping > there are affordable linear actuators as well. > > > Bret Cahill
Dunno if your "electric crank" won't use more energy than it saves. Stirling cryocoolers use a pair of pistons in opposition with a spring in between. You end up being held to one frequency, but they work. -- www.wescottdesign.com
> >> > The goal is an Stirling w/o a mechanical crank/flywheel. Instead > >> > it'll have 2 electric actuators and a linear generator. > >> > > >> > Supposedly a linear generator, a glorified shake light, can be 95% > >> > efficient. I need an actuator that is pretty efficient as well. > >> > > >> > The actuators need a to consume less than 100 watts and have a stroke > >> > of ~ 15 cm. > >> > > >> > Since it is only for demonstration purposes it is OK if it is run off > >> > of software/USB. > >> > > >> > > >> > Bret Cahill > >> > >> > >> How do you propose to keep the gas sealed within the chamber? > > > > An "electric crank" allows the entire thing to be hermetically sealed. > > No moving parts extend out of the casing, only some wires. Same for > > some free piston. > > > > The biggest unsung advances in technology include servos so I'm hoping > > there are affordable linear actuators as well. > > > > > > Bret Cahill > > Dunno if your "electric crank" won't use more energy than it saves.
It doesn't have to be 95%.
> Stirling cryocoolers use a pair of pistons in opposition with a spring in > between. You end up being held to one frequency, but they work. > > -- > www.wescottdesign.com