Abstract

Skin friction drag reduction via turbulence manipulating implies a purposeful influence on a very complicated mechanism of vortical structure dynamics with wide range of scales and the disturbances localized in the wall vicinity. The goal of this research is to propose the complex unified approach for semi-empirical modeling of turbulent viscosity with possibility to take into account both simultaneous and separate influence of such factors as: streamlined surface relief (from macro ribs to microgrooves), uniform and intermitted microblowing, polymer additives injection and Large Eddy BreakUp devices. There are three principal advantages of the developed model: 1) It has hybrid structure, joining algebraic (in the wall region) and differential (in the wake region) modeling descriptions, that makes them very flexible in various cases of different turbulent flows prediction; 2) It is built on the base of common principles and its potential generalization to the case of heat conductivity modeling doesn't require the use of Reynolds analogy (incorrect in the vicinity of the rough surface) in the wall region of turbulent boundary layer; 3) The proposed approach is not limited by only RANS level of flow modeling, it can be effectively adapted for improving the near-wall subgrid turbulence model in frames of LES/DES techniques. The elaborated model due to its ability to take into account the mentioned above factors both independently and in different combinations demonstrate universal approach that allows to simulate simultaneous acting the different flow control methods, investigate their non-linear interaction and optimize geometric characteristics and operating conditions for searching the synergistic modes of functioning. The applicability of the developed model is proved by qualitative agreement of wide range of mentioned above kinds of turbulent flows predictions and the experimental results, obtained by different researchers. The proposed modeling approach can be recommended for its application in different research and engineering fields, associated with turbulence vortical structure manipulating.

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