Finally, the submerged equipment also requires rework, which makes using a two-phase system much more expensive. The price starts at an average of $130 per liter! Secondly, to use Novec you need an absolutely leak-proof tank with a system of increasing pressure compensation. However, the two-phase cooling system based on Novec has a number of drawbacks that make its use in home mining practically impossible, and in industrial mining it is associated with disproportionately high costs for organizing such a system. You can read more about how Novec liquid immersion cooling systems work in this article: Novec and Coolant liquids comparison - why we stick to our own formula. Due to the natural evaporation, condensation and cooling of the fluid, the system does not need internal circuit pumps, complex and expensive heat exchanger and some other elements. The above-mentioned compositions do not have the highest boiling point, which correlates with the operating temperature of the elements and effective heat transfer. Remarkably, in the two-phase cooling system, only fluorocarbon fluids can be used, filling it with oil makes no sense.

Most often, the 7000, 71 compositions are used for the two-phase system. It should be said that Novec has proven itself in two-phase and single-phase cooling systems for mining equipment. In recent years, 3M has even managed to create an image of Novec as a 'specially modified fluid for miners,' which has only increased its credibility, combined with the company's 120-year history. It is transparent, nonflammable (used for extinguishing fires in electronics), odorless, has various boiling points, excellent dielectric properties, and is compatible with most components of computing equipment. The latter was regularly criticized for its ozone-depleting substances and indirect effects on global warming, so in 1996 it was replaced by Novec, devoid of the shortcomings of its predecessor.įluorine-Novec is truly unique in many ways. It gave the world transparent duct tape, magnetic audio tapes and Fluorinert, a fluorine-containing refrigerant. Novec is a product of the American industrial chemicals corporation 3M. Novec fluid may be the best, but it's expensive So what is the best liquid for immersion cooling of computing equipment? Let's find out. But behind the loud names there are well-known variations: synthetic polyalphaolefin oils, organosilicon oils, fluoro ketones and others. Please refer to the following table of degree of toxicity.Over the past few years, dozens of compositions have appeared in the world under the label 'the best liquid for immersion cooling'. It is usually expressed as 'LD50' (50% Lethal Dose). Generally speaking, this test determines the amount of a substance that constitutesĪ lethal dose when administered at one time to a test animal. LD 50 is over 5,000 mg/kg for both males and females. There is slight inflammation of the conjunctiva,īut to a far lower degree than that caused by typical detergents. Number of test subjects: 20 (Japanese Society for Cutaneous Health)Ībsolutely no effect on the cornea or iris. Silicone fluid was applied on a patch to the inside of a human subjects' upper arm and the reaction observed with a microscope after 24 hours. ☌ for viscosities below 20 mm 2/s, and approximately 0.36 cal/g.The specific heat of DM-FLUID is 0.39-0.47 cal/g The values are comparable to common organic compounds that have low specific heat. The specific heat of silicone fluid varies somewhat depending on viscosity, but is generally about one-third that of water. ☌ at viscosities below 20 mm 2/s, and roughly 3.7-3.8x10 -4 cal/cm.The thermal conductivity of DM-FLUID is 2.4-3.5x10 -4 cal/cm Although thermal conductivity increases with higher viscosities, it becomes nearly constant at viscosities above 100 mm 2/s. The thermal conductivity of dimethyl silicone fluid is lower than that of common organic compounds (nearly the same as that of benzene and toluene) and is roughly 25% that of water. Viscosity change rate by temperature (0☌ - 50☌) Thermal Conductivity Temperature - kinetic viscosity change of silicone fluids

Mineral oil viscosity vs silicone oil