water cooling

[daddz]

i have decided to go ahead and water cool one of my headline motors with copper coated steel tube used by a local hydraulic shop. i want to see what others think of the idea? question first
is the copper coated steel tubing going to affect the magnets?
is it worth finding and getting some copper tube shipped in at about twice the cost?
i have several choices of tube size from about 8mm od down to 4mm od, im going with the smaller size i think to have more contact area, small as it be.
the plan is to coil the tube around the motor starting about 15mm from the end of the casing and going right up to where the motor changes shape, with both ends of the tube extending between 8cm and 15cm behind the motor all depends on which part of the frame i mount the tank on.
which would be better?, a loosely wrapped coil around the motor with gaps between each wrap/twist? or a tightly wrapped coil with no gaps between each loop?
whichever is used im planning to use some sort of silastic or computer heat sink paste in the middle part of the coils, so there are no air spaces and for better heat transfer with a 2 part metal bonding agent at the ends to keep it all in place.
i have several options to use as water tanks, or if i can find it a small old gearbox cooler but i doubt the air flow would be enough to be worth using it at the speeds i ride.
water flow i have a fish tank pump that runs on 24v its pretty small and should do the job ok even at the slower flow rate due to the lower voltage, or i will get one of these http://www.buyincoins.com/item/34689.html
the water tank will be mounted behind the motor, at this stage im thinking of using a metal flask or one of those metal drink bottles that hold about 750mls of water, or even an empty aerosol can, i have a few options and ideas for that like an old sla battery with the insides removed.
camera has been fixed so here's a pic of the motor its going on.

 

[knighty]

what's the motor casing made of ?

you really need a mechanical fixing there (welding) to get decent heat transfer

4mm pipe it too small for decent heat transfer too, do with 10mm

a more powerful pump would help too, 4litres/min max is a bit slow

for a radiator, look at PC water cooling radiators, you'll easily be able to get fans to fit too!



but, a lot easier, and probably even more effective if you can't weld the pipes to the motor case is just better air cooling - you could thermal epoxy some fins onto the motor, to increase surface area, add a cowling (tube) around it to focus the air path, and then add a hefty blower fan

you could probably even get a DC controller for the fan motor, to run it on/off/up/down as needed depending on the temperature of the motor

 

[daddz]

thats another option but im keen on using water, even if just as an experiment that will only cost a few bucks to complete. also i feel more capable of finishing this with my skills than molding a cowling from scratch, so is it really worth trying or not? cost wise its cheap as chips to do the water setup with what i have at hand, to mold something i would need to buy all the needed parts and a fan and switch.
another option ive mulling over is to have it as a 100% loss system and just pump water through it every minute or so when needed, ie, going uphill pulling a loaded trailer, or use gravity fed to save having a pump.
i thought the smaller tube would be more suited to the flow rate and allow more actual contact to the motor shell? which im guessing is cast alloy of some sorts. maybe instead of a tank, i use several pc water coolers hooked together? or even simpler would be another coil or two of the same or larger tubing? and the pump hooked up somewhere in between them all.
putting this on my trike so i have plenty of room and another kilo of weight wont be a problem, and that will be mostly water.

 

[Cowardlyduck]

Try air cooling mate, it works well.
http://endless-sphere.com/forums/viewtopic.php?f=30&t=56965&start=100#p1009434

Cheers

 

[knighty]

for the cowling, you just need a big bit of pipe... plastic will do fine

for the fins, just measure about how long they need to be, and then by some copper sheet (or whatever) on ebay

water cooling by wrapping the motor with pipes is a waste of time tbh... it would work if there was a big temperature difference between the motor and the pipes... but you want to try and keep the motor as cool as possible so that's not much good for you... you just can;t get good enough contact between the motor case and the pipes :-(


I guess, if your heart is really set on water cooling, you could wrap the motor as tight as you could with the pipe (doing 1 coil at a time) then add a load of thermal epoxy (a lot) the idea being that by the time you've finished there won't be any air gaps between the pipes and the motor case, just thermal epoxy... but it would be hard to do and not make a mess / guessing it'll cost a fair bit for all that thermal epoxy!

 

[h0tr0d]

Forget about water, just oil cool it
https://rnmentropy.wordpress.com/2014/02/26/oil-cooling-with-nanofluids/

Two holes on the motor, redline oil, oil pump and a PC radiator
http://www.redlineoil.com/product.aspx?pid=25&pcid=18

 

[Drunkskunk]

Yes, Steel will effect the motor. you're experience field weakening, which will give you more RPM but cost you some torque. How much would be hard to calculate. Copper will be less, but a coil of conductive material around the motor is still an inductor. it will effect the motor, though maybe not enough to notice. Really, for thermal conductivity, you should use Aluminum tubing. An even better idea would be a single "tube" or some form of water jacket that only looped around the motor once, giving you maximum surface contact with the motor.


I agree with others, air cooling would be better. Oil cooling would be second best. But it can't hurt to try your idea.

 

[daddz]

im in three minds at the moment, i think water has the best potential to remove heat quickly, so im tossing up between a fan and cowling ( not keen on extra wires), a drip fed water system to remove heat as needed (going uphill towing a load) by just washing the motor down with a slow feed of water (water getting on the phase wires is only concern and i will need to move the controller)) or the third which im leaning towards, is to make a water jacket out of poly pipe attached simply with silastic. (finding suitable size may be tricky)
after attaching the external controller yesterday and several climbs on the hills around here the motor was about as hot as when the old cyclone internal controller would cut out, but i did go extremely hard testing it, so im pretty sure i need to do something to tow a load without worrying about heat buildup.

 

[ioo]

hi,
because you have an in-runner motor it is good your idea with water cooling. i use water cooling to my motors too.
my method it is : i take an O-ring rings and put it on one and other extremity of the motor and after i put an external custom made cylinder ( it is not important it is aluminum or fiber glass made .... ) because the water not have much time to warm so much because travel it is very short and the space from 2 cylinders it is big to have good cooling . on the external cylinder need to make 2 holes one for intake the water and other for out.
it is a simple method and it works , i drive my motors at 50-60 Amps continues.

 

[daddz]

not sure when this will get finished now :| lots of major changes in the household leave me with little coin to spend and maybe moving house before the year ends.