AP19678220 "Nanofluid coolant on the basis of TiO2 for use in a hybrid solar collector"

According to the calendar plan for 2023 (Annex A), the operating conditions of the heat carrier for the hybrid solar collector have been determined, taking into account the climatic features and heat flows of the regions of the Republic. A methodology has been developed for the production of stable hybrid nanoparticles based on TiO₂ using water/ethylene glycol-based base fluids and combined dispersed phases (TiO2/ZnO, TiO2/Al2O3, TiO2/CuO, TiO2/MWCNT). In order to increase the stability of dispersion, the effectiveness of surfactants (CTAB, SDBS and Tween 80) at different pH values was experimentally evaluated. Taking into account the data obtained, a laboratory test bench was designed and assembled to conduct thermal-physical studies of nanostructures intended for use in a hybrid solar collector.

According to the calendar plan for 2024, the thermal-physical properties of stabilized nanostructures based on the TiO2/ZnO, TiO2/Al2O3, TiO2/CuO, and TiO2/MWCNT systems were studied. The laws of thermal conductivity, thermal conductivity, viscosity and thermal conductivity (temperature conductivity), which depend on the concentration of nanoparticles in the base fluid, were determined. Hydrodynamic studies on the flow modes of nanoparticles were carried out, the correlations of the Nusselt and Reynolds numbers were obtained as a function of particle concentration, as well as the patterns of pressure loss, which depend on the Reynolds number and the size of the solid phase, were established. The energy and exergetic efficiency of the hybrid solar collector was evaluated and compositions with the optimal ratio of nanoparticles and surfactants were determined.

According to the calendar plan for 2025, a set of accumulated experimental data on hybrid nanostructures based on TiO2 was analyzed and the model characteristics of heat and mass transfer in the range of temperatures and compositions characteristic of the conditions of operation of a hybrid solar collector were clarified. A theoretical generalization was made describing the hydrodynamic behavior and heat exchange of nanostructures in specific circulation modes in the circuit. Based on the results obtained, practical recommendations have been developed on the selection of nanosoil composition for a hybrid solar collector using thermal carriers based on TiO2, the methodology for its preparation, circulation modes and operating conditions.

Based on the results of the Study, 2 articles were published in peer-reviewed scientific publications indexed in the web of Science and Scopus databases and 1 article was reviewed by the reviewer, 3 articles were published in the domestic publication recommended by the State Technical University of the Republic of Kazakhstan, as well as a patent of the Republic of Kazakhstan for a utility model "installation for thermal and Physical Research of hybrid solar collectors" and a monograph "thermal properties of hybrid nanostructures" was published, recommended by the Academic Council of the University.