Better as coolant, water or water/ethylene glycol mix? urgent!

[richard027]

Hi all

I am working on a guarded heat plate that is cooled with a heat exchanger type arrangement through the cold plates above and below the test specimens.

My question is this - I have to choose a coolant, the cooling unit has text on the side that recommends either water or water and ethylene glycol in a 60/40 mix. This coolant is to be at constant 15 degrees celsius. Which option would be best? Should I add a surfactant if I use water?

Initially I was going to test both, the water then the mixture but the existing test apparatus is quite fragile and I am afraid that running many tests will break it and I don't have a lot of time on the apparatus. Any advice or alternatives will be greatly appreciated and I'm sorry if this is very long-winded, it's my first post.

I would appreciate some quick responses as I have to make a decision tomorrow!

 

[waross]

On the one hand, if the flow rate of the coolant may be a limit, compare the specific heat of water and the specific heat of ethylene glycol mix and calculate the needed flow rates for each.
On the other hand, you mentioned broken test apparatus. Consider the implications of a water leak versus an ethylene glycol leak.
yours

 

[quark]

A 60/40 mix of ethylene glycol is an overkill for a 15⁰C coolant and will rob you of energy. Water is the best coolant upto 6⁰C. Further, ethylene glycol is a toxic substance and you should take care of it if the statute recommends.

 

[bewdley]

No match. Water, absolutely. Go to Glycol/water only for sub-zero (centigrade) jobs.

 

[richard027]

Hello again,

Thanks to everyone who responded. I have went with water on the basis of the advice given, thanks again for the tips!

Richard