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https://sites.google.com/view/icacm18/program/ NEW UNIVERSAL CLASSIFICATION OF FLUID FLOWS STRUCTURAL COMPONENTS Yuli D. Chashechkin A.Yu. Ishlinskiy Institute for Problems of Mechanics of the RAS Conventional mathematical classifications of fluid flows (potential - vortex by Euler, laminar - turbulent by Stokes-Reynolds, Prandtl’s boundary layer), based on an analysis of the solutions of the corresponding systems of equations, play an important role in both theoretical and experimental fluid mechanics. It is necessary to emphasize an important feature of known classifications – they are based on either reduced or constitutive systems of equations. The development of mathematical methods of analysis, computers and information technologies allow to operate with complex systems of differential equations and to make a universal classification of the components of fluid and gas flows. The new classification is based on the analysis of complete solutions of the system of fundamental equations, including the equations of state and the differential equations of mass, momentum, energy and matter transport. Different rates of energy exchanges in flows are analyzed. The system is characterized by a ten-parameter Galilean transformation group, showing compatibility of the system with the basic principles of physics. New spatio-temporal scales invariant classification of fluid flows components, which includes fine ligaments, waves, and vortices is given. In case of infinitesimal motions, the family of the complete solutions of the linearized and non-linear systems of the fundamental equations for weakly dissipative media contains regular and singular perturbed functions, which are calculated for internal waves of different types. The calculated flow patterns compare with schlieren visualization of flows around oscillating and uniformly moving bodies in stratified tanks. Recommendation on improvement of compatible calculations of flows and experiments with the fluid and gases are discussed. References. 1. Chashechkin Yu. D. Differential fluid mechanics – harmonization of analytical, numerical and laboratory models of flows: Mathematical Modeling and Optimization of Complex Structures”. 2016. V. 40. P. 61-91. DOI: 10.1007/978-3-319-23564-6-5 2. Chashechkin Yu. D. Singularly perturbed components of flows – linear precursors of shock waves // Math. Model. Nat. Phenom. 2018. V. 13. No. 2. P. 1-29. https://doi.org/10.1051/mmnp/2018020 3. Zagumennyi I.V. Chashechkin Yu.D. Unsteady vortex pattern in a flow over a flat plate at zero angle of attack (2D problem) // Fluid Dyn. 2016. V. 51(3). P. 343-359. https://doi.org/10.1134/S0015462816030066 4. Chashechkin Yu. D., Zagumennyi I. V., Dimitrieva N. F. Unsteady Vortex Dynamics Past a Uniformly Moving Tilted Plate // Topical Problems of Fluid Mechanics - 2018, Prague. February 21 – 23, 2018. Proceedings. 47 – 56 (2018). DOI: /10.14311/TPFM.2018.007 5. Chashechkin Yu. D. Waves, vortices and ligaments in fluid flows of different scales // Phys. Astron. Int. J. 2018. V. 2(2). P. 105-108. https://doi.org/10.15406/paij.2018.02.00070