The Origin of Shear Turbulence
Journal Title: INCAS BULLETIN - Year 2017, Vol 9, Issue 4
Abstract
Previously, the turbulent flows were studied as they have been disregarding their origin, and without looking into some of the details of the mechanism of turbulence production and sustainment. This approach focusing its attention particularly on the details of the fluctuating motion superimposed on the main motion led to most of controversial and misunderstood results from which the law of equal action and reaction, and the circulation-conserving were excluded. The paper is aiming at removing these drawbacks and presenting the turbulence phenomenon as a mechanical process triggered off at the beginning of motion. The fluid as deformable continuum without a definite shape must be guided by some physical surfaces, where the rotor-translational motion approximation is more suited than the no-acceleration parallel flow approximation. The main features of shear turbulence are described by means of the mechanical prototype of a perturbed rotor-translational motion continuously self-accelerating at wall and conserving the mass and angular momentum.
Authors and Affiliations
Horia DUMITRESCU, Vladimir CARDOS
Relativistic Contact-Wall Effects at Start-up
General relativity describes the physical force of gravity and its relation with the space-time structure. The fundamental physical insight behind the theory of general relativity is that the effects of acceleration cann...
The laminar boundary layer on a rotating wind turbine blade
The present paper describes a method to calculate velocity profiles in the boundary layer of rotating blade. A differential approach is used to solve the laminar boundary layer equations. The effects of tip speed ratio,...
Theoretical and numerical method in aeroacoustics
The paper deals with the mathematical and numerical modeling of the aerodynamic noise generated by the fluid flow interaction with the solid structure of a rotor blade. Our analysis use Lighthill’s acoustic analogy. Lig...
The analysis of the process tending towards equilibrium in transitional and turbulent wall flows
Starting from the integro-differential formulation (IDF) [1], [2] of the basic conservation equations in wall flows, the authors perform a qualitative analysis of the microscopic-macroscopic domain. According to IDF, the...
Fluidic Elements based on Coanda Effect
This paper contains first some definitions and classifications regarding the fluidic elements. The general current status is presented, nominating the main specific elements based on the Coanda effect developed speciall...