FLAIR Tutorial 5: A room with sunlight

This tutorial models a three-dimensional room, consisting of two windows, one closed, one open and an open door. Sunlight is coming at -30 degrees in the Z-X plane to the room through the closed window as shown below. The patches showing on the floor and the wall are the projected sunlight shadows. This case shows how to set the sunlight object.

Setting up the model

Start FLAIR with the default room

The FLAIR VR-Environment screen should appear, which shows the default room with the dimensions 10mx10mx3m.

Resizing the room

Adding objects to the room

a. add a door

X: 1.0 M

Y: 0.0 m

Z: 2.0 m

X: 0.0 m

Y: 0.0 m

Z: 0.0 m

b. add the open window

X: 1.0 m

Y: 0.0 m

Z: 1.0 m

X: 0.84 m

Y: 5.0 m

Z: 1.2 m

c. add the sunlight window

The Shapemaker default screen

The List of shapes

Length (X) - 3m; Width (Y) - 5m; Height (Z) - 2.7m

Please note that the wall where the window is located is largely controlled by the Angle between the ray direction and X axis as follows. It is obvious that the window can be only on the West wall if 0 degree in XY plane is specified and on the East wall if 180 degree in XY plane is specified.

The Sunlight Object parameters

The Sunlight object

To activate the physical models

a. The Main Menu panel

FLAIR always solves pressure and velocities. The temperature is also solved as the default setting.

The 'Models' page of the Main Menu.

b. To activate LVEL turbulence model

Select 'LVEL' turbulence model

To set the grid numbers and to solver parameters

in X-direction to 20 cells

in Y-direction to 30 cells

in Z-direction to 15 cells

The 'Geometry' panel

You can click on the 'Mesh toggle' button, on the main control panel to view the grid distribution on the screen.

The grid distribution

Set the total number of iterations to 300 on the Numerics panel

Running the Example

To run the PHOENICS solver, Earth, click on 'Run', then 'Solver', then click on 'OK' to confirm running Earth. These actions should result in the PHOENICS Earth monitoring screen. To the end of the calculation, the monitoring display would be as shown below.

EARTH monitoring screen

As the Earth solver starts and the flow calculations commence, two graphs should appear on the screen. The left-hand graph shows the variation of solved variables at the monitoring point that was set during the model definition. The right-hand graph shows the variation of errors as the solution progresses.

Viewing the results

The iso-surface contours at temperature of 20.12 degree C

Saving the case

Once a case has been completed, it can be saved to disk as a new Q1 file by 'File - Save working files'. The Q1 and associated output files can be saved more permanently by 'File - Save as a case'.