Stirling Cryocooler
Posted: Tue Jun 23, 2009 9:49 am
Hi All,
I am no expert with Stirling Engines and I will be glad to get some
expert help from the senior members here. Please help. Thank You
A week ago I completed setting up a Alpha Stirling engine using a
friends lathe machine. I actually wish to run it as a cryocooler or
heatpump. The engine consists of the following parts.
a) Two copper cylinders with epoxy-graphite pistons - Maximum
cylinder capacity is 20 ML of air volume at full stroke per cylinder
b) Regenerator - A Stainless Steel cylinder (2 inch by 2.5 inch)
tightly packed with steel wool
c) Heat Exchangers - The hot and cold heat exchangers are made out of
two very thin aluminium tubes (1inch * 2.5 inch)
d) The crankshaft is connected to the cam such that one piston moves
90 degrees ahead of the other piston.
e) The flywheel is made of cast iron which is connected to a 120 watt
8000 RPM motor.
When I connect power to the motor, I expect the cold heat exchanger
to absorb heat and the hot heat exchanger to release heat and
therefore function as a heat pump. But the trouble is, both the heat
exchangers are getting pretty hot. The heat exchanger and cylinder
connected to the follower piston gets much more hotter than the heat
exchanger and cylinder connected to the leading piston. The
regenerator feels slightly warm to the touch.
Could someone please tell me what I'm doing wrong. Why is'nt the cold
end cooling down? I'm at the end of my wits now. Every ounce of help
I can get will be greatfully accepted. Thanks a ton in advance
I thought I got everything figured out theorectically. But when I put
my ideas into practise, boy was I wrong.
Basically I started out wanting to make my own Stirling cryocooler. I
have been working very hard spending long hours learning every little
information I could find on the Internet. I learnt that the Alpha
configuration gives the best performance and so I thought that I had
better utilize that for my Stirling Cooler.
I am no expert with Stirling Engines and I will be glad to get some
expert help from the senior members here. Please help. Thank You
A week ago I completed setting up a Alpha Stirling engine using a
friends lathe machine. I actually wish to run it as a cryocooler or
heatpump. The engine consists of the following parts.
a) Two copper cylinders with epoxy-graphite pistons - Maximum
cylinder capacity is 20 ML of air volume at full stroke per cylinder
b) Regenerator - A Stainless Steel cylinder (2 inch by 2.5 inch)
tightly packed with steel wool
c) Heat Exchangers - The hot and cold heat exchangers are made out of
two very thin aluminium tubes (1inch * 2.5 inch)
d) The crankshaft is connected to the cam such that one piston moves
90 degrees ahead of the other piston.
e) The flywheel is made of cast iron which is connected to a 120 watt
8000 RPM motor.
When I connect power to the motor, I expect the cold heat exchanger
to absorb heat and the hot heat exchanger to release heat and
therefore function as a heat pump. But the trouble is, both the heat
exchangers are getting pretty hot. The heat exchanger and cylinder
connected to the follower piston gets much more hotter than the heat
exchanger and cylinder connected to the leading piston. The
regenerator feels slightly warm to the touch.
Could someone please tell me what I'm doing wrong. Why is'nt the cold
end cooling down? I'm at the end of my wits now. Every ounce of help
I can get will be greatfully accepted. Thanks a ton in advance
I thought I got everything figured out theorectically. But when I put
my ideas into practise, boy was I wrong.
Basically I started out wanting to make my own Stirling cryocooler. I
have been working very hard spending long hours learning every little
information I could find on the Internet. I learnt that the Alpha
configuration gives the best performance and so I thought that I had
better utilize that for my Stirling Cooler.