Watercooling and flow: is there such a thing as too much flow??

[tlandauer]

Sounds very good, buy what about the K.I.S.S. Cooling system?

[lt130th]

Sounds very good, buy what about the K.I.S.S. Cooling system?

LOL. Be sure to read my previous comment as facetiously as it sounds. But I live in the same state as the member I replied to, & it is HOT here this time of year so sometimes stupid ideas for staying cool start to sound less stupid, haha. I don't know if it's common most places but the majority of grocers around here all stock dry ice, and they are regularly sold out in the summers.

[tlandauer]

Yeah, I hear you, in So Cal the weather can be just as hot, so the motor/ESC starts out at 90* already. Any measure that can cool them is good.

Sent from my D6708 using Tapatalk

[runzwithsizorz]

The issue this creates has to do with energy. First you need to power that pump. That means adding the weight of an extra battery, unless you want to cut your run time down from 7 minutes to 5 minutes by running a pump off your main LiPo cells. That weight means your powertrain is being taxed a little more which will also shorten your run time & increase the heat in the electronics that you were trying to make cooler. Also the pump & its power source will add temp's to the interior of the hull. Everything has a cost when dealing with energy, and you never get out what you put in, due to friction & other variables. So you try to do something to improve a system but only make things worse or no change at all...unless you want to drag a weightless, frictionless barge behind the boat, covered in solar cells, & mount the pump outside the hull...

GOPR0041.JPG

I have a show boat that I often let sit on the water for up to an hour. after a couple of pass's, and I let it sit idle once again, I will activate a pump for a minute or so to cool things down, using a third channel. The boat has 3 temp probes, and telemetry. The pump is a diaphragm type so it needs no priming. Will operate on 4 to 12 volts, weighs 1.2 oz , and is 1.4 cu. in. Works on milliamps, heat is minimal.
NEVER SAY NEVER!

[lt130th]

[ATTACH=CONFIG]134746[/ATTACH]

I have a show boat that I often let sit on the water for up to an hour. after a couple of pass's, and I let it sit idle once again, I will activate a pump for a minute for so to cool things down, using a third channel. The boat has 3 temp probes, and telemetry. The pump is a diaphragm type so it needs no priming. Will operate on 4 to 12 volts, weighs 1.2 oz , and is 1.4 cu. in. Works on Milliamps.
NEVER SAY NEVER!

So you avoid generating too much extra heat by running the pump for only a short burst, and your actual run time of the boat is a couple SAW passes? Does the pump have a dedicated power source? If not, this could be an answer to pump cooling an FE boat under these circumstances. How does the third chanel trigger the pump (electronic switch or mechanical like a servo)? The heat generated by the pump and the power consumed required would be minimal due to the short interval, however, the additial mass is still there (albeit seemingly insignificant). The more Watts or horsepower in the powerplant, that 1.2oz becomes more neglible, of course (horsepower to weight ratio). For example, I've seen twin FE HPR's that do 130mph with a pump that is on, constant, over the duration of the run. Those are SAW boats that run for 2-3 minutes. Then you find yourself wondering how much faster you can go if you ditch the extra weight. The age-old battle. Of course it can be done. The science doesn't change (like running an oscillating fan in a closed room for a period of time), but rather the application & terms of use. I don't know that any pump would be viable for reducing temp's (beyond the typical setup) in a common 4s-6s setup that is used for sport running.

[dmitry100]

kfxguy: How do you think is the best way to setup the cooling lines for twin SF or T180 type Esc's? I always figured keeping the shortest path is the way to go... but now I'm thinking it might be a good idea to have both ESC's use both lines equally (like style #3).

-- Dual cooling lines --
Style #1 (Keeping both inlet/outlets completely separate to each side) which is what I have right now:
(Inlet 1) --> ESC 1 --> Motor 1
(Inlet 2) --> ESC 2 --> Motor 2

Style #2 (I see these on some T180 setups):
(Inlet 1) --> ESC 1 --> ESC 2 --> Motor 1
(Inlet 2) --> ESC 1 --> ESC 2 --> Motor 2

Style 3 (Benefits of each ESC having both inlets equally):
(Inlet 1) --> ESC 1 --> ESC 2 --> Motor 1
(Inlet 2) --> ESC 2 --> ESC 1 --> Motor 2

[runzwithsizorz]

So you avoid generating too much extra heat by running the pump for only a short burst, and your actual run time of the boat is a couple SAW passes? Does the pump have a dedicated power source? If not, this could be an answer to pump cooling an FE boat under these circumstances. How does the third chanel trigger the pump (electronic switch or mechanical like a servo)? The heat generated by the pump and the power consumed required would be minimal due to the short interval, however, the additial mass is still there (albeit seemingly insignificant). The more Watts or horsepower in the powerplant, that 1.2oz becomes more neglible, of course (horsepower to weight ratio). For example, I've seen twin FE HPR's that do 130mph with a pump that is on, constant, over the duration of the run. Those are SAW boats that run for 2-3 minutes. Then you find yourself wondering how much faster you can go if you ditch the extra weight. The age-old battle. Of course it can be done. The science doesn't change (like running an oscillating fan in a closed room for a period of time), but rather the application & terms of use. I don't know that any pump would be viable for reducing temp's (beyond the typical setup) in a common 4s-6s setup that is used for sport running.

This is obviously not a race, or saw boat, just a little eye candy out on the lake, especially when the sun starts going down, she has a lot of lights which I can also control remotely. She is a heavy 13lb. 33in. deep vee, but still capable of 45+. She is powered by a Neu 1527, 2300kv and 13000mah 4s, with a 300amp complete Eagletree system attached to a 900mhz transponder. With a larger prop she can heat up pretty quick, in spite of having 4 water pick-ups, but it's fun as heck for a minute or so. Receiver, lights, pump, servo, and *electronic* 7 way switching device is powered by a 2700mah 2s with a regulator, (6.5volts). I can SEE the temps drop when I engage the pump on the Seagull dashboard screen attached to my TX, and/or my laptop.
Mind you, this set up can really only be used, (realistically) in the manner of which I am using it. Just one of my many toys. DOBY was correct, "more is better" kinda explains why many years ago a friend and I put a 327ci in the back seat of his Corvair.

[kfxguy]

kfxguy: How do you think is the best way to setup the cooling lines for twin SF or T180 type Esc's? I always figured keeping the shortest path is the way to go... but now I'm thinking it might be a good idea to have both ESC's use both lines equally (like style #3).

-- Dual cooling lines --
Style #1 (Keeping both inlet/outlets completely separate to each side) which is what I have right now:
(Inlet 1) --> ESC 1 --> Motor 1
(Inlet 2) --> ESC 2 --> Motor 2

Style #2 (I see these on some T180 setups):
(Inlet 1) --> ESC 1 --> ESC 2 --> Motor 1
(Inlet 2) --> ESC 1 --> ESC 2 --> Motor 2

Style 3 (Benefits of each ESC having both inlets equally):
(Inlet 1) --> ESC 1 --> ESC 2 --> Motor 1
(Inlet 2) --> ESC 2 --> ESC 1 --> Motor 2

I'll post in my build how I'm going to do it. Im waiting on a fitting I need that I ordered yesterday from ose store. It's already on the way to me.

[dmitry100]

kfxguy: ok cool. Btw, do you think electronics are put under more stress when the stingers are set to any angle besides neutral? I have noticed my temps go down a bit after changing it back to neutral from either slightly positive or negative. So should I make less use of the negative stinger angle or keep it neutral and just rely more on the Cg? And just to be sure-- stinger angle is measured from the top-most edge of the 2nd to the last (transom) step, right?

[kfxguy]

kfxguy: ok cool. Btw, do you think electronics are put under more stress when the stingers are set to any angle besides neutral? I have noticed my temps go down a bit after changing it back to neutral from either slightly positive or negative. So should I make less use of the negative stinger angle or keep it neutral and just rely more on the Cg? And just to be sure-- stinger angle is measured from the top-most edge of the 2nd to the last (transom) step, right?

I know the electronics are more stressed if you have the stinger set negative and the boat is running wet. With the stuff I've messed with, neutral worked good for going really fast and a little positive worked well for going mode really fast efficiently. There's a lot more to it than that but that's the short of it.

[MarkF]

Too much water flow is when your water lines pop off inside the boat and start filling your boat up with water. There is a point where you have to much pressure from too good of water flow. I had a 10s saw mono do this and yes I had zip ties on all the fittings. When that didn't work we stuck a piece of antenna tubing inside the water line trying to constrict the flow and zip tied that but still no luck. It turns out the tubing itself was too soft and the pressure was trying to blow it up like a balloon. So more water flow is always better, until it causes a problem.

Mark

[nichismo]

did you completely skip the OP? more flow is contradictory of pressure increase.... ESPECIALLY when the cooling system isn't even a closed loop that's been bled of remaining air, something impossible with our boats....this is scientific fact.... if the situation you presented indeed occurred at some point that you experienced or witnessed it, assure yourself that flow was not the root cause

[Brewbud]

Lines a poppin! Unregulated high flow trying to squeeze through small lines = high pressure. I had this happen on a brewing system with silicone lines. Reducing the flow at the output end increased pressure and caused the 1/2" silicone line upstream to swell up like a 4 foot balloon and pop. Pretty funny to see. Fortunately it was a water line and not a beer line at the time!

Lesson learned - entire system must be designed to handle the maximum pressure ..... or uhhh...don't touch that valve right dere

[lt130th]

A few key terms will help everyone communicate effectively on this subject. Fluid traveling through a tube follows the principle of mass conservation. The result is that the product of the density, velocity & cross-sectional area of the mass entering the tube is equal to the product of the density, velocity & cross-sectional area of the mass exiting the tube. Therefore, if you change any one of these variables at a time, at one end, variables will have to change at the other end. And for FE boating cooling systems we can assume desity remains constant. Keep this rule handy in your mind during this discussion.

[zooma]

This has me worried about using a "Y" fitting inside the boat. One leg goes through the ESC and its exit fitting. The other leg goes through the cooling jacket and its exit fitting. The cooling jacket seems to have much reduced flow. So, is all the water going to exit through the ESC path, leaving the motor to overheat. If so, should I use a restricted size exit on the ESC line to force water through the cooling jacket line?