Introduction

The test case comprises a 2-D box section, across which a uniform flow is applied. A passive scalar is introduced in a circular region at the start time, and transported across the domain. By looking at the profile of the scalar across the section, we can determine the characteristics of our time scheme selection.

Case set-up

The impact of the choice of time scheme is assessed by varying the ddt scheme entry of the fvSchemes file:

ddtSchemes
{
    ddt(phi)        <time scheme>
}

Boundary conditions

Velocity boundary conditions

Patch Type Value
left fixedValue (1,1,0)
right zeroGradient  
top zeroGradient  
bottom fixedValue (1,1,0)
frontAndBack empty  

Scalar boundary conditions

Patch Type Value
left fixedValue 0
right zeroGradient  
top zeroGradient  
bottom fixedValue 0
frontAndBack empty  

Initial field

Mesh

Case set-up

Results

Euler results

Time 1 Time 2 Time 3

backward results

Time 1 Time 2 Time 3

Crank-Nicolson results

Time 1 Time 2 Time 3