IMPROVING TEMPERATURE DISTRIBUTION EFFICIENCY USING A SWIRLING AIR JET
DOI:
https://doi.org/10.31650/2786-6696-2025-14-103-109Keywords:
aerodynamics, turbulent flows, swirling jet, temperature, excess temperature, temperature attenuation coefficient.Abstract
Effective control of thermal processes in air flows is an important condition for improving the energy efficiency of ventilation and heat engineering systems. The aim of the study is to analyze the processes of reducing excess temperature in an isothermal free swirling air jet, followed by the improvement of approaches to regulating the thermal characteristics of the flow. The relevance of the work is determined by the need to enhance the energy efficiency of ventilation systems and heat engineering equipment through the optimization of temperature fields. The main task consisted in analyzing the processes of thermal decay, calculating the corresponding coefficient, and constructing temperature profiles in cross-sections of the jet. To simplify the mathematical description, a temperature attenuation coefficient was introduced, which makes it possible to more clearly assess the dynamics of heat dissipation. A quantitative study of axial temperature distribution was carried out, dependence graphs were constructed, and the nature of changes in different jet zones was determined. An efficient method for calculating relative temperature values in arbitrary cross-sections was proposed. To account for the influence of gravitational forces on the development of the thermal field, the dimensionless Archimedes number was applied. The temperature distributions in the jet were described on the basis of a generalized analytical model similar to the Schlichting model, adapted to thermal problems. The results of the study are presented in the form of generalized graphical dependencies and formulas with correction coefficients. A comparison of experimental observations with analytical modeling results demonstrated a high degree of agreement between the obtained data and theoretical predictions. The analysis also covers the formation of turbulent thermal structures during jet cooling. The possibility of regulating the temperature profile by changing boundary conditions and initial parameters is shown. The obtained conclusions can be effectively applied in the design of ventilation systems, heat engineering equipment, and energy units, where the uniformity of temperature distribution in the air environment is critical. The presented results provide a foundation for further research on nonlinear heat transfer effects under external disturbances and will contribute to the development of algorithms for automatic microclimate control in enclosed spaces.
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