Plus 2.X:3D-Objects

General Information

Figure 1: The 3D-Object

WUFI plus offers the possibility to model 3D thermal bridges. In this chapter the procedure is explained using the easy example of a thermal bridge you can see in the picture on the left.

Figure 2: The Input Mask

A new 3D Object can be created by clicking on the "New" button in the 3D Objects section. The newly created Object appears in the Navigation Tree and can be edited then. The whole input mask looks like shown in Figure 2.

Measures

The first step is inputting the right measures along x, y, and z axis, this is done in this part of the input mask.

Figure 3: Measure-Input

For each change of material, a new division must be created and dimensioned. This can be done by using the "New", "Delete", "Copy" and "Insert" button. According to Figure 1, input should look like this:

Figure 4: Finished Measure-Input

Figure 5:Materials

Materials and Boundary Conditions

The second step is to assign the right materials and boundary conditions. First, requested materials need to be selected from the database using the "Add" button. In this case brick and concrete is chosen (see Figure 1).

Figure 6:Materials and boundary conditions along the x-axis

In principle to assign a material or boundary condition to the right element, choose the division, select the material or boundary condition and click onto the element.

X-Axis

If this is done in the x-axis tab, the procedure is the following:

• Imagine you look at the 3D-Element in direction of the green arrow in the picture.
• Imagine you "cut your element into slices" along the measurement units. As you can see in Figure 6 you get five "slices" (or divisions): Boundary Condition on the outside, 1,2,3 and Boundary Condition on the inside.

Figure 7: First Division-B.Cond.

• It is started with the uppermost division, the Boundary Condition (B. Cond.)[1]. After clicking onto it, this "slice" is displayed in the picture below. The first division is the Boundary Condition i.e. the outer air so "climate" [2] is selected and then it is clicked onto the elements you see in the picture below[3]. Doing so outer climate is assigned to them and they turn blue.

• 

  Figure 8: Second Division
  Next the second division is selected, this is section 1 in Figure 6 above. Obviously the whole area is brick, so brick is selected and then assigned to the elements by clicking onto them. The outer elements remain untouched, they are adiabat, there is no heat exchange happening through them as they are only the continuance of the walls.
  
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  Figure 9:Third Division
  After that, the third division is chosen, this is area 2 in Figure 6. This "slice" of the wall has both a brick and a concrete part. The outer parts are brick, the inner one is concrete.
  
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  Figure 10: Fourth Division
  The fourth division (area 3 in Figure 6) gets concrete assigned to its middle part and as the two outer areas are inner air, they belong to "Zone 1:Heated Zone".
  
• Last the fifth division remains untouched, it's adiabat.

Figure 11:Input Y-Axis

Figure 12:Input Z-Axis

Y-Axis and Z-Axis

If the input made for the x-axis was right, input for y and z axis is right to automatically. However check it, to make sure everything is correct. If everything was done correctly input should look like the input in Figure 11 and 12

Graphic Window and Monitor Positions

Figure 13: Graphic Window

After finishing all tasks above the display of the 3D Element should look like this.
There are a couple of operations in the graphic window:

• Number 1
  • Rotating around X, Y and Z Axis (use left and right mouse for different directions)
  • Centering the display
  • Zooming in (left mouse) and out (right mouse)
• Number 2: The elements to be shown can be selected user defined.
  • It is possible to display all elements
  • Also only selected materials (i.e. ONLY concrete or ONLY masonry)can be displayed
  • It can be decided whether only one layer should be displayed (Select this layer on the left side in one of the tabs (X,Y,Z) and choose the desired division.
• Number 3: Display of boundary conditions can be switched off, if you do so, only the "solid" materials are displayed.
• Number 4: You can set monitor positions. Click the button and another window opens up where you can enter coordinates. Note, that these coordinates belong to the coordinate system that was used to input the 3D-Object, e.g. the one shown in Figure 1. If monitor positions were defined, they are displayed as dots in the picture on the down left side of the input window. For these monitor positions temperature is calculated during and values can be found in the export-section after a calculation.

"Initial temperature" and "Show fine division"

Figure 14: "Initial temperature" and "Show fine division"

• Before a calculation the initial temperature of the elements can be set
• Show fine division: During a calculation temperature distribution in the different layers and divisions of 3D element is displayed and can be looked at. If "Show fine division" is checked, the display is smoother but the calculation is slower.