Kraton Water-cooled XL Kraton

[Arrmadog1990]

The extra coolant capacity is just a heat battery, and a heavy one at that. The idea isn't to store heat with extra coolant, what you want is to move heat via the radiator and get rid of it. You are using a flexible Tygon type tubing, which will handle any thermal expansion in your low-volume system. Keep it simple and easy to maintain. Remember, your car gets shaken up like that beer can your grinning buddy just handed you when you bash, so a bled system without air space (reservoir headspace) will survive the abuse without pump cavitation and stall, and boy do impeller pumps stall.

As far as chems go, knock yourself out (for science!). Be careful, you're going to get that stuff all over your car eventually, and you don't really know what's going to get eaten by the additives. A full scale car motor produces tens of kilowatts of heat, and a RC motor produces a couple of hundred at peak. A 5% improvement on the car's thermal efficiency is a lot of heat, but the same gain on the puny RC car system is single digits- so I argue the effort isn't worth it. Again, keeping it simple makes sense.

Ahhhh this makes sense very good info my dude thanks !! Ya I’m not gonna mess with the additives didn’t really think about the lines being able to expand!! This is perfect I like simple and no heavy reservoirs!

Honestly I believe temps will be worse imho. Just a prediction based on what I see on boats.
Air flow around cans is pretty efficient in these designs, but only one way to find out

When taking temps, check the front and back of the motor, don't fall into the cooling mantle trap like a lot of folks do.
The water mantle is physically isolated with rubber gaskets and relies on water/air transmission.
If all works, it's an ok indicator, but it will misguide if there are issues in water circulation.

10-4 will do sir! Also I hope your wrong lol like you said only one way to find out! And we gonna find out that’s for sure !

+1 on avoiding a coolant tank/revivor. I think keeping it much like a 1:1 car's cooling system is ideal.
I don't believe you would have any issues with expansion due to the flex in the lines and if temps got to 180+ you have other issues anyway...

Perfect! I’m officially doing away with the reservoirs you guys have convinced me and ya definitely trying to stay well under 180 Hahahha

 

[rotauq]

As a PC watercooling & RC nerd i've done this before. Used the same pump btw. I did attach a tiny reservoir directly to the pump inlet. At this scale a closed system is better.
My conclusion was it's cool, but not cooler than aircooling.
The added weight=more load=more heat and the limited cooling capacity can't disperse all the heat.
It will remain closer to ambient temperature for a few minutes and then the water/coolant will get too hot, exceeding the cooling capacity.

Seen many good comments already, so don't know what i should still add.

 

[Arrmadog1990]

As a PC watercooling & RC nerd i've done this before. Used the same pump btw. I did attach a tiny reservoir directly to the pump inlet. At this scale a closed system is better.
My conclusion was it's cool, but not cooler than aircooling.
The added weight=more load=more heat and the limited cooling capacity can't disperse all the heat.
It will remain closer to ambient temperature for a few minutes and then the water/coolant will get too hot, exceeding the cooling capacity.

Seen many good comments already, so don't know what i should still add.

Ahhhhh dammit !!! Ya I was afraid of that. Water getting heat soaked and the radiator not able to keep up. What radiator were you using ?

 

[rotauq]

Ahhhhh dammit !!! Ya I was afraid of that. Water getting heat soaked and the radiator not able to keep up. What radiator were you using ?

I went looking for it and found it in the basement. It was this 80x80 radiator (including a 80x80x15 fan, not on the picture):

 

[Arrmadog1990]

I went looking for it and found it in the basement. It was this 80x80 radiator (including a 80x80x15 fan, not on the picture):
View attachment 174096

Woooord well I hope mine works better!! Hahahah but your scaring me a little here my guy

 

[rotauq]

Woooord well I hope mine works better!! Hahahah but your scaring me a little here my guy

I hope so too, but don't get your expectations up too high. You're running 2x high rpm fan's so maybe that will do the trick...
Certainly test the concept first before you spend too much money on it

 

[LibertyMKiii]

One other factor I learned from automotive racing with high revving 8k-9.5k rpm motors is that the water pump speed can be an issue also. If the water passes through the radiator/heat exchanger too quickly the ability to cool the water is reduced.

You could slow the pump down with PWM via an Arduino board and motor driver, but then again we are adding more failure points...

Hopefully that is a non issue.

 

[Arrmadog1990]

One other factor I learned from automotive racing with high revving 8k-9.5k rpm motors is that the water pump speed can be an issue also. If the water passes through the radiator/heat exchanger too quickly the ability to cool the water is reduced.

You could slow the pump down with PWM via an Arduino board and motor driver, but then again we are adding more failure points...

Hopefully that is a non issue

I was thinking about this as well thinking I could run lower power to the pump to slow it down and one of the reasons why I wanted the pump pressurizing a reservoir and having the water jackets feed off of that because I think it would decrease the pressure from the pump a little bit and make stuff move a little slower but ya I guess I won’t know until I start recording data after it’s running. I think my motor is a 2080kv

 

[Monster Dork]

With that little pump, there are enough restrictions in the system to prevent any problems with dwell/contact time for heat transfer. You've got the most powerful 40mm fans out there doing the work. That part's gonna be okay. So let's see it already!

 

[Arrmadog1990]

With that little pump, there are enough restrictions in the system to prevent any problems with dwell/contact time for heat transfer. You've got the most powerful 40mm fans out there doing the work. That part's gonna be okay. So let's see it already!

Hahaha I’m trying!! Hopefully get a test run this weekend if I get my controller and receiver soon sir soon!!

 

[jkflow]

The flow issue is probably no issue at all. The little nipples restricting flow through the rather large reservoir around the motor. That is what will naturally restrict flow and allow for heat exchange.

 

[Arrmadog1990]

The flow issue is probably no issue at all. The little nipples restricting flow through the rather large reservoir around the motor. That is what will naturally restrict flow and allow for heat exchange.

Perfect this is great to hear and I’m hoping this to be true ! Just hope my radiator is sufficient which in my mind with the high rpm fans it should be good! Really hope I get a test run in this weekend !

 

[Ginglehopper]

Perfect this is great to hear and I’m hoping this to be true ! Just hope my radiator is sufficient which in my mind with the high rpm fans it should be good! Really hope I get a test run in this weekend !

You can always get another radiator and stack them or something, right?

 

[Arrmadog1990]

You can always get another radiator and stack them or something, right?

Yessir I’m prepared to try that if this one won’t keep up! Just be hard to fit another one I’d like to do another one of the same size but that may not be feasible time will tell gotta get some temp numbers and runs in to see where the system is at as far as cooling capability and go from there! Really hoping I don’t need another one lol

 

[Arrmadog1990]

I know I said I wasn’t doing the reservoirs anymore but I already had them mounted and they look awesome lol and since they are mounted I might as well try them and see here’s a pic!

 

[Arrmadog1990]

Plumbing is done just have to put some gorilla glue on the lines where they go into the reservoirs and have my brother wire my fans and water pump to a connector for the 3s battery! I’m feeling a test run this weekend my dudes!! Hopefully I can make the damn body fit

 

[Monster Dork]

You made some interesting choices by pressurizing one reservoir (series plumbed) and running parallel with a splitter to your motor cooling blocks. I hope you can get out this weekend for some test runs, I'm anxious to see your results!

 

[Arrmadog1990]

You made some interesting choices by pressurizing one reservoir (series plumbed) and running parallel with a splitter to your motor cooling blocks. I hope you can get out this weekend for some test runs, I'm anxious to see your results!
View attachment 174267

Bruh that’s great hahahahaha I’m glad your ready hopefully I won’t disappoint!! Good eye 👁 on my plumbing I’m pressurizing the one reservoir mainly so I can have both of the feed lines to the water jackets getting fresh cool water from the reservoirs rather than having them in series and the second water jacket getting hot water from the first jacket. I also wanted to possibly drop the pressure from the pump a little bit by doing that but I’m not totally convinced it will work like that but ya like I said mainly for the first reason! Then the other reservoir is obviously just a low pressure return reservoir for the radiator return and the pump to suck from!

 

[ChemEng]

One other factor I learned from automotive racing with high revving 8k-9.5k rpm motors is that the water pump speed can be an issue also. If the water passes through the radiator/heat exchanger too quickly the ability to cool the water is reduced.

This is just not true. Increasing coolant flow will result in better heat transfer performance.

If the flow rate is too low, you will not achieve full turbulent flow which is required for good heat transfer. Increasing flow rate past that will have little benefit, but will not have a negative effect on heat transfer.

 

[LibertyMKiii]

This is just not true. Increasing coolant flow will result in better heat transfer performance.

If the flow rate is too low, you will not achieve full turbulent flow which is required for good heat transfer. Increasing flow rate past that will have little benefit, but will not have a negative effect on heat transfer.

That is good to know.
I believe the real source of the issue from the automotive side must not be the speed of water flow, but spinning the water pump too fast was creating cavitation....