Looking for a design for a small pump to add coolant flow to my engine design

[checkedout]

Wondering if you could point me to a design out there. I'm thinking of a small canister/piston style pump that I could add to my walking beam engine design (using the lever action of the beam as the driving force on the pump).

I have some 6063-T8 Aluminum stock that would likely work well for the pump body.

Anything simple out there? I'm sure I could come up with a design with rubber flappers and stuff like that, but if there's some pre-existing plan I could base my design off of (or double check my own work), I think I'd be much better off.

Your thoughts?

 

[mklotz]

A piston driven up and down in a cylinder equipped with inlet and outlet, each fitted with a ball check valve, will do the job fairly simply.

I'm curious. Why would a beam engine need coolant? Is it a Stirling?

 

[checkedout]

Sorry... I left out that detail.

Yes, it's a Stirling.
I'd like to help with efficiency so, I'm just spitballing ideas to water cool the upper part of the displacer cylinder.

 

[shred]

What kind of heat source are you planning on? Pumping losses will probably outweigh any gained efficiencies unless you run it really hot.

I'd start by just dunking the cold end in a tank of water first if air-cooling doesn't do it. If the water tank gets too hot, then look at active cooling.

 

[checkedout]

Sounds reasonable to me.

I'll stick with a basic form factor, and keep the frilly additional stuff for my next one.

or... maybe just get the thing running and add the extra parts later.

 

[Longboy]

Do a lift station pump and kill two birds! Cool the engine and show work by driving a water pump.

 

[mklotz]

Shred's concern is germane. With a small Stirling you don't have much spare power to drive a pump. Consider using a static cooler tower. The top of the engine water jacket is attached to the top of the tower and the bottom of the jacket to the bottom of the tower.

As the water in the jacket warms it flows into the top of the tower and the resulting partial vacuum pulls cold water from the bottom of the tower into the jacket. Obviously, when equilibrium is reached the process stops but I'm assuming this is a model engine not meant to be run for long periods of time.

 

[Longboy]

........Ya with a Stirlings beam moving fast a lift pump might not be ideal. But a lever actuated diaphram pump or pulley driven mag pump has possibilitys. Without knowing the size of the model you may find that its water jacket around the hot cyl. without coolent or a no flow pool around this cyl. will be enough heat rejection. My Robinson Twins Stirling runs fine without any coolent, an accidental discovery. Jerry Howell has plans for a model water pump of which you can adapt the concept to your own design but it is pulley operated.

http://www.jerry-howell.com/MagDrivePump.html