Hello to all. I have built my first tin can stirling engine by following Mr. Boyd's directions (thank you) and after some adjustments, I was able to get it to run. Next I plan to add some instrumentation to do some analysis (it's for a school project). Has anyone measured the hot and cold air temps and the pressure in the cylinders? I'm trying to determine if I can use a manometer or if I'll need a psi pressure gauge.
I use a non-contact infrared thermometer to measure surface temperatures on the engine. I have not measured pressures. You might be able to glean a little info by reading about this engine: http://stirlingengine.com/product/29
In case anyone is interested, I measured my tin can engine.
Air temperature inside displacer:
Hot air temp = 275 deg C
Cold air temp = 102 deg C
Gauge pressure in power cylinder:
Contraction stroke = -4 inches of water
Expansion stroke = +3 inches of water
Hi
Im very interested.
How did you measure? In practical I mean,instruments,pressure connections ....
The indication of more Contraction force than Expansion force
confirms the subjective "feeling",I have from experiments.
For the temperatures, I used type K thermocouples. I drilled a small hole in the top and bottom of the displacer cylinder and inserted the tip of the thermocouple into the dead air space between the displacer piston and the displacer cylinder.
For the pressure, I drilled a small hole at the base of the power cylinder and inserted a small (probably <2mm OD) metal tube. It’s in the dead air space between the power piston and the displacer cylinder. I then attached a plastic tube, shaped it into a “U” shape, filled it with water to make a manometer.
Good point Ian. My speed was 130 rpm. Is that about normal? Can I ask how you measured the torque? I need to do that with mine but haven't thought of a good method.
Thanks
I don't have a copy of Rizzo's book. Would it be possible for someone who has it to scan and post the picture? does anyone have a photo of their own torque measurement device? What values of torque are you all getting from your tin can engine?
If you just want to show the poweroutput you can attach a little dc-motor to the flyweel and a multimeter to show the poweroutput.
Voltage/revs or with a load (LED) amps/rev.
Check this for a cheap and easy rev.counter:http://stirlingengineforum.com/viewtopic.php?f=1&t=580
Best of luck with your project.
Jan
Next I plan to add some instrumentation to do some analysis (it's for a school project). Has anyone measured the hot and cold air temps and the pressure in the cylinders? I'm trying to determine if I can use a manometer or if I'll need a psi pressure gauge.