On the two-dimensional steady turbulent flow of a compressible fluid far behind a solid symmetrical body. I. (Momentum transfer theory)

1949 ◽  
Vol 247 (1) ◽  
pp. 33-61 ◽  
Author(s):  
M.Z. Krzywoblocki
Keyword(s):  
Turbulent Flow ◽  
Momentum Transfer ◽  
Compressible Fluid ◽  
Two Dimensional ◽  
Transfer Theory ◽  
Symmetrical Body

Re-examination of vorticity transfer theory

1977 ◽  
Vol 354 (1676) ◽  
pp. 1-8 ◽  
Keyword(s):  
Momentum Transfer ◽  
Turbulent Diffusion ◽  
Constant Coefficient ◽  
Shear Flows ◽  
Turbulent Shear ◽  
System Of Equations ◽  
Two Dimensional ◽  
Exchange Coefficient ◽  
Loss Of Information ◽  
Transfer Theory

The averaging procedure required to generate the Reynolds equations for turbulent shear flows results in a loss of information. The system of equations is no longer closed, and additional assumptions are required. The classical closure assumptions are based on Taylor’s (1915, 1932) vorticity transfer theory and Prandtl’s (1925, 1942) momentum transfer theory. In this paper we show that the former is in a very fundamental sense incorrect in that only for very special forms of the eddy exchange coefficient (including a constant coefficient) does turbulent ‘diffusion’ of vorticity also conserve momentum. For expository purposes much of the discussion is centred on an idealized simple two dimensional wake in which momentum and vorticity are conserved transferable properties.

Concerning the velocity and temperature distributions in plane and axially symmetrical jets

1938 ◽  
Vol 34 (2) ◽  
pp. 185-203 ◽  
Author(s):  
L. Howarth
Keyword(s):  
Turbulent Flow ◽  
Momentum Transfer ◽  
Fair Agreement ◽  
Transfer Theory ◽  
Momentum Theory ◽  
Temperature Distributions ◽  
Plane Jets ◽  
Theoretical Results ◽  
Good Agreement

The calculations of the velocity and temperature distributions for the turbulent flow in axially symmetrical and plane jets are described.For axially symmetrical jets Tollmien's results derived from calculations based on the momentum theory are stated; the calculations on the basis of the modified vorticity transfer theory and on the vorticity transfer theory with symmetrical turbulence are carried out. Unfortunately it seems to be true that none of these theories provides results in good agreement with experiment for both the velocity and temperature distributions.For plane jets the results obtained by Tollmien and based on the momentum transfer theory are stated; the calculations on the basis of the vorticity transfer theory are carried out. The velocity distributions on both theories are identical and in fair agreement with experiment. In order to test the validity of the theories it is necessary to compare the theoretical results for the temperature with experiment. No results for the latter seem to have been published.

Analysis of Frost Growth through a Two-Dimensional Duct with Turbulent Flow

2008 ◽  
Vol 39 (4) ◽  
pp. 347-370
Author(s):  
M. Salmanpour ◽  
O. Nourani Zonouz ◽  
Mahmood Yaghoubi
Keyword(s):  
Turbulent Flow ◽  
Two Dimensional ◽  
Frost Growth

Level set-based topology optimization for two dimensional turbulent flow using an immersed boundary method

2021 ◽  
pp. 110630
Author(s):  
Seiji Kubo ◽  
Atsushi Koguchi ◽  
Kentaro Yaji ◽  
Takayuki Yamada ◽  
Kazuhiro Izui ◽  
...  
Keyword(s):  
Topology Optimization ◽  
Turbulent Flow ◽  
Level Set ◽  
Immersed Boundary Method ◽  
Immersed Boundary ◽  
Two Dimensional ◽  
Boundary Method

Modification of turbulence caused by cationic surfactant wormlike micellar structures in two-dimensional turbulent flow

2021 ◽  
Vol 933 ◽  
Author(s):  
Kengo Fukushima ◽  
Haruki Kishi ◽  
Hiroshi Suzuki ◽  
Ruri Hidema
Keyword(s):  
Turbulent Flow ◽  
Surfactant Solution ◽  
Turbulent Energy ◽  
Molar Ratio ◽  
Wormlike Micelles ◽  
Two Dimensional ◽  
Turbulence Statistics ◽  
Image Velocimetry ◽  
Set Up ◽  
Induced Structure

An experimental study is performed to investigate the effects of the extensional rheological properties of drag-reducing wormlike micellar solutions on the vortex deformation and turbulence statistics in two-dimensional (2-D) turbulent flow. A self-standing 2-D turbulent flow was used as the experimental set-up, and the flow was observed through interference pattern monitoring and particle image velocimetry. Vortex shedding and turbulence statistics in the flow were affected by the formation of wormlike micelles and were enhanced by increasing the molar ratio of the counter-ion supplier to the surfactant, ξ, or by applying extensional stresses to the solution. In the 2-D turbulent flow, extensional and shear rates were applied to the fluids around a comb of equally spaced cylinders. This induced the formation of a structure made of wormlike micelles just behind the cylinder. The flow-induced structure influenced the velocity fields around the comb and the turbulence statistics. A characteristic increase in turbulent energy was observed, which decreased slowly downstream. The results implied that the characteristic modification of the 2-D turbulent flow of the drag-reducing surfactant solution was affected by the formation and slow relaxation of the flow-induced structure. The relaxation process of the flow-induced structure made of wormlike micelles was very different from that of the polymers.

Computational Fluid Dynamics Techniques for Flows in Lapple Cyclone Separator

2005 ◽  
Vol 498-499 ◽  
pp. 179-185
Author(s):  
A.F. Lacerda ◽  
Luiz Gustavo Martins Vieira ◽  
A.M. Nascimento ◽  
S.D. Nascimento ◽  
João Jorge Ribeiro Damasceno ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Experimental Data ◽  
Computational Fluid Dynamics ◽  
Turbulent Flow ◽  
Reynolds Stress ◽  
Cyclone Separator ◽  
Two Dimensional ◽  
Stress Components ◽  
Computational Fluid Dynamics Cfd

A two-dimensional fluidynamics model for turbulent flow of gas in cyclones is used to evaluate the importance of the anisotropic of the Reynolds stress components. This study presents consisted in to simulate through computational fluid dynamics (CFD) package the operation of the Lapple cyclone. Yields of velocity obtained starting from a model anisotropic of the Reynolds stress are compared with experimental data of the literature, as form of validating the results obtained through the use of the Computational fluid dynamics (Fluent). The experimental data of the axial and swirl velocities validate numeric results obtained by the model.

Sign in / Sign up

Export Citation Format

Share Document