[Amps] liquid cooling

[Ron Youvan]

Larry wrote:
> The recent discussion on water cooling amp tubes got me thinking. Again. 
> (not a good thing)
> 
> Basically I would like to play with liquid cooling but I can't/won't use 
> water. While I was still working, I worked on a multi-kilowatt amplifier 
> that was oil cooled. It went into the avionics bay of an aircraft where 
> all the rest of the equipment was also oil cooled.
> 
> As I recall, the oil looked and felt like mineral oil, but I'm sure the 
> military wouldn't use something that common and cheap and low flash 
> point. At the time, I pulled up the MSDS for the oil but no longer have 
> it and of course I can't remember the numbers.
> 
> K8CU talks about using ATF for cooling liquid here:
> 
> http://www.realhamradio.com/liquid-cooling.htm
> 
> Unfortunately, there is no indication in the article that he or anyone 
> else actually used ATF. Now ATF contains sulphur compounds that eat 
> silver plating and cannot normally be used in things like dummy loads 
> because of this property. However, a set of heat exchangers used for 
> tube cooling would not have that problem.
> 
> K8CU also mentions mineral oil and says it is not suitable due to the 
> low flash point. I have to wonder about that because for one I would 
> hope nothing in a system I would build would ever get hot enough to 
> worry about flash point and two, it probably won't flash anyway due it 
> being in a closed system with little or no free air/oxygen.
> 
> What I'm looking for is someone who has actually done liquid cooling 
> with something other than water. No, I have no interest in "flat earth" 
> theories, or what you think you remember from a thermodynamics class you 
> sat through 40 years ago. I want actual test results and operational 
> data from real world applications.

   The L3 company has a division that makes "MDC IOT" transmitting tubes, their date for 
these tubes indicates the cooling oil they use, which is a synthetic fluid.
-- 
    Ron  KA4INM - The next election, I know what is going to happen, I'm going to help.