Example2 Turbulent Flow between Parallel Plates

General

  • The steady-state analysis is applied to the fluid which is flowing at the constant velocity between the parallel plates.
     

  • The fluid velocity distribution, the turbulent flow energy distribution, and the fluid velocity vectors are solved.
     

  • Unless specified in the list below, the default conditions will be applied.
     

  • Obtain this session's project file. (Save the project file before open)

 

Analysis Space

Item

Setting

Analysis Space

2D

Model Unit

mm

 

Show Results

Item

Setting

Solver

Fluid Analysis [Bernoulli]

Analysis Type

Steady-State Analysis

Laminar Flow/Turbulent Flow

Select Turbulent Flow

Meshing Setup

General Mesh size: 1[mm]

Model

The material of Air (000_Air) is set to a rectangular sheet body. The boundary conditions of inlet and outlet are set on the left edge and the right edge respectively.

The solid wall outer boundary condition is automatically applied to the top and bottom edges where the boundary condition is not set.

 

Body Attributes and Materials

Body Number/Type

Body Attribute Name

Material Name

0/Solid

pass

000_Air(*)

* Available from the material DB

Boundary Condition

Boundary Condition Name/Topology

Tab

Boundary Condition Type

Setting

Inlet/Edge

Fluid

Inlet

Forced Inflow
Specify fluid velocity
50[m/s]

Outlet/Face

Fluid

Outlet

Natural Outflow

 

The Reynolds number calculated from this model form, material property, and fluid velocity is about 33104. The turbulent flow is analyzed as the number is large.

Generally, the laminar flow transitions to turbulent flow at the Reynolds number in the order of 1000.

 

Viscosity μ=1.82e-5[Pa s]

Density ρ: 1.205[kg/m3]

Kinematic viscosity v=μ/ρ=1.82e-5/1.205=1.510e-5[m2/s]

Fluid velocity V=50[m/s]

Distance between plates L=0.01[m]

Reynolds number Re = V*L/ν=50*0.01/1.510e-5 = 33104

Results

The distribution of the fluid velocities is shown below.

 

 

A graph below is given by selecting [Graph on edge] after right-clicking an edge near the outlet.

 

 

Unlike [Example 1 ] where the laminar flow is analyzed, the fluid velocity changes suddenly near the wall surface. The velocity is flat near the center.

 

The analysis result of K_turbulent flow energy is shown below.

 

 

The turbulent energy near the wall surface is high.