Best liquid for IC sprayer

[mpg99999]

Someone recently told me that they where using ethyl alcohol on a homemade Intercooler sprayer (similar to the NX nitrous sprayer kits, but with water, or in this case, alcohol instead. Same thing that the new subaru wrx sti has). Would ethyl alcohol work better? I know water has a higher specific heat, but what about the heat of vaporization? What numbers to I need to look at to figure this out? Thanks.

-Mike

 

[patprimmer]

Ummmm

Ethyl alcohol is quite flamable. If it sprays over the intercooler, then vaporises then hits a red hot exhaust, there is a slight but I expect unreasonable risk of an engine bay fire.

I think a mix of 50/50 alcohol and water sprayed inside the intercooler is what you might be thinking about.

Please do a search on water injection as this subject has been discussed add nausium in the past

Regards
pat

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[mpg99999]

Yeah, I forgot to ask about the whole flamability thing. I thought of this as well. I am not asking about alcohol or water injection.

-Mike

 

[obanion]

A methanol/water mix would work better than straight water. You want to keep the mix under the flammibility limit though. Under 40% should do the trick. It will smell very strong of methanol (pleasant sweet smell) when in use.

 

[mpg99999]

So why would a methanol mix work better? What information do I need to look at to figure stuff like this out? Heat of vaporization?

-Mike

 

[drwebb]

Why indeed?

Heat of Vaporization:
Ethanol 204 cal./g; b.p. 78.5 C
methanol 263 cal./g
Water 540 cal./g; b.p. 100 C

The water absorbs 2 times the heat, but at 21% higher temperature.

 

[obanion]

Evaporation rate.

Pour water on your hand, wave it in the air. Pour methanol on your hand, wave it through the air. The methanol will make your hand feel COLD, the water won't.

 

[ozgurinal]

Methanol vapor may be dangerous to inhale. you should take it into account.
Methanol vaporizes faster than water so that it abosorbs more heat than water in that temprature.
Water has bigger latent heat of vap but if you spray more methanol you can eleminate this advantage of water.

 

[obanion]

Sure methanol fumes are bad if you put your head over a contrainer of it and inhale deeply for a few minutes.

The whiff of smell you will catch from using it on a IC won't hurt you.

Methanol will evaporate and cause cooling. Most of the water will just go through the intercooler, through the radiator, into the engine compartment.

Depends on humidity too. If you live in a very dry climate, water would work great by itself. If it's humid, methanol will help the cooling greatly.

 

[patprimmer]

If the methanol evaporates, and the water does not, you still get flamable gas.

Methanol has some cumulative effects as a toxin.

I will look up an MSDS on both methanol and ethanol.

By the way, ethanol is also toxic, but because we have been injesting it for thousands of years because of it's intoxicating effect, we accept the toxicity. I believe that if it were invented today, it would never pass FDA as a food additive.

Regards
pat

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[patprimmer]

This link might help

http://www.syndel.com/msds/denatured_ethanol_msds.html

Regards
pat

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[patprimmer]

So might this one

http://www.msdssearch.com/DBLinksN.htm

Regards
pat

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[drwebb]

"By the way, ethanol is also toxic, . . . I believe that if it were invented today, it would never pass FDA as a food additive."

Was it Hipocratus (Hippocratus? Hypocrattis?) that observed 'The difference between medicine and poison is the dosage'.