On 5/22/19 12:49 AM, Christian Corti via cctalk wrote: > On Tue, 21 May 2019, Patrick Finnegan wrote: >> Plumbing (unless you're doing aisle containment or RDHx) shouldn't run >> through the IT space in the data center. > > So how exactly do you attach a modern water cooled rack system to your > cooling water system if not using plumbing?
So how are data centers cooled with water now? Does the water cool coldplates directly? I've had only a couple of instances where cooling water was used. In the case of CDC mainframes, it was used to cool the condenser coils in the refrigeration units (located in the mainframe). I believe that Cray initially used the same guy that CDC used to fabricate the cooling tubing. I recall visiting the Honeywell plant in Phoenix not long after they took it over from GE and the engineers there were tinkering with a direct water-cooling setup--water circulated in each rack (connected by what was probably vinyl tubing, I don't recall, only that it was translucent), with copper diaphragms serving as the interface between the water and the semiconductors. I recall from comments made that algae was a problem and adding an algicide to the cooling water tended to corrode the copper diaphragms. To the best of my knowledge, this was a test setup--it certainly had an impressive instrumentation unit with multiple CRTs and neon thermometer-type displays. The most extreme example I ever ran into of cooling was the ETA-10 supercomputer--cooled with liquid nitrogen, supplied by a cryostat. I don't recall what cooled the latter. --Chuck
