The study examines the velocity decay processes in an isothermal free swirled air jet to improve methods for controlling the aerodynamic characteristics of air flows. The objective is to intensify the velocity decay in the supply air of an isothermal free swirling jet, determine the decay coefficient, and analyze axial velocities by constructing their profiles in cross-sections. To simplify calculations, the velocity decay coefficient “m” is introduced. The decay coefficient is determined, an analysis of axial velocity distribution is conducted, and corresponding graphs are constructed. A comparison of experimental data with theoretical models is performed. The features of turbulent structures formed during the decay process are investigated. The possibilities of regulating jet dynamics by modifying input parameters are considered. The obtained results can be used to optimize processes in various technical and industrial applications, including ventilation systems, gas dynamic installations, and energy complexes.
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