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Information × Registration Number 0222U002010, 0117U002714 , R & D reports Title Development of scientific bases of production and use of nanoliquids to improve the safety and efficiency of energy equipment, in particular of nuclear reactors popup.stage_title Head Bondarenko Borys Ivanovych, Доктор технічних наук Registration Date 09-02-2022 Organization The Gas Institute of the National Academy of Sciences of Ukraine popup.description2 1. The task of nanofluids (NFs) creating on the basis of Ukrainian natural aluminosilicates for use as heat carriers at boiling is set and solved for the first time. The expediency of their use as NFs for cooling superheated heat transfer surfaces is proved. 2. Composite NFs are proposed and created for the first time in the world, which provide the largest critical heat fluxes among the NFs known today. 3. The physical model of NFs boiling and the mathematical model of temperature distribution in a cylindrical rod are offered. Based on these models, an automated control algorithm was created, which was used to create a computerized unit for the study of heat transfer during NFs boiling. 4. Boiling curves and values of heat transfer coefficients for a wide range of developed NFs are obtained on this installation. Studies for most NFs have shown the absence of a "sudden" boiling crisis. This results in a reduced relationship between the decrease in heat transfer coefficient and the specific heat flux at boiling. In this regard, a separate concept was introduced - "crisis phenomenon" at NFs boiling. 5. The influence of various factors (nature and concentration of solid phase, shape and anisometry of particles, additives, dispersant, surfactants and electrolytes, the state of the heating surface) on the value of the critical heat flux at boiling NFs is studied. It is established that the values of CHF and the maximum achievable specific heat flux during boiling of aluminosilicate NFs are higher, the greater the anisometry coefficient of nanoparticles. This is due to the fact that as a result of the deposition of nanoparticles when boiling NFs with strongly anisometric particles, the surface of the heater becomes more porous and rough, and roughness and porosity dramatically increase the heat transfer surface area and the number of vaporization centers. 6. It was found that NFs based on attapulgite are more stable to long and multiple boiling-cooling cycles   Product Description popup.authors popup.nrat_date 2022-03-09 Close