![]() ![]() Therefore, all materials in the cooling loop must be corrosion-resistant.Ĭopper and many other common materials are not compatible with DI water and will contaminate it. In fact, to a varying degree, it will dissolve everything to which it is exposed. Called the "universal solvent," DI water is one of the most aggressive solvents known. The very lack of ions also makes this coolant unusually corrosive. ![]() Applications that require the use of DI water are found in industries such as:Ĭare must be exercised when using DI water. The lack of ions in DI water eliminates both of these problems. The arcing can damage sensitive control electronics in the equipment being cooled. Second, it eliminates the risk of electrical arcing due to static charge build up from the circulating coolant. This will degrade cooling efficiency and system operating performance. First, it eliminates mineral deposits which block the coolant flow. However, deionized (DI) water has chemical and electrical properties that make it the optimal choice for cooling when the liquid circuit contains micro-channels or when sensitive electronics are involved.Īs the name implies, DI water has an extremely low concentration of ions which imparts important performance attributes. ![]() Tap water meets the needs of most liquid-cooling applications. When using deionized water in cold plates or heat exchangers, stainless steel tubing is recommended. The fittings should be nickel-plated and the evaporators should be nickel-brazed. When using deionized water in a recirculating chiller special high purity plumbing is needed. It is necessary to use a corrosion inhibitor when using water that is virtually pure. The carbon dioxide in air will dissolve in the water, introducing ions and giving an acidic pH of around 5.0. Deionized water will pH at approximately 7.0 but will quickly become acidic when exposed to air. However, as water's resistivity increases, its corrosivity increases as well. Deionized water is an excellent insulator which is why it is used in the manufacturing of electrical components where parts must be electrically isolated. ![]() Compared to tap water and most fluids deionized water has a high resistivity. The deionization process removes harmful minerals, salts, and other impurities that can cause corrosion or scale formation. (See Table 1.) Most cooling systems are compatible with water or glycol/water solutions but require special plumbing for compatibility with deionized water or a dielectric fluid such as polyalphaolefin (PAO).ĭeionized water is water that has had its ions removed, including sodium, calcium, iron, copper, chloride, and bromide. When using deionized water or other corrosive fluids, however, stainless steel is generally recommended since it is more corrosion resistant than other metals. Copper is compatible with water and glycol/water solutions and aluminum is compatible with glycol/water solutions, dielectric fluids, and oils. Based on these criteria, the most commonly used coolants for liquid cooling applications today are:īy selecting a compatible pairing of heat transfer fluid and wetted materials you'll minimize the risk of corrosion as well as optimize thermal performance. Some other requirements for a heat transfer fluid may include high thermal conductivity and specific heat, low viscosity, low freezing point, high flash point, low corrosivity, low toxicity, and thermal stability. Heat transfer fluid compatibility is critical in ensuring long-term system reliability. ![]()
0 Comments
Leave a Reply. |