Uf- and �-calculation

for window frame sections and IG spacer according to EN ISO 10077-2

with WinIso2D

Short description

Sommer Informatik GmbH Sepp-Heindl-Str. 5 83026 Rosenheim Phone: 0049 – (0)8031 – 24 88 1 Fax: 0049 – (0)8031 – 24 88 2 Email: info@sommer-informatik.de Internet: www.sommer-informatik.de

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Content

Content.................................................................................................................... 1

Preparing the CAD drawing..................................................................................... 2

Converting the DXF drawing ................................................................................... 3

DXF conversion with a macro (batch file) ................................................................ 8

Creating WinIso2D project and calculating the Uf-value according to EN ISO

10077-2 ................................................................................................................... 9

Calculation of � (Psi, linear thermal transmittance) of IG spacer according to EN

ISO 10077-2 .......................................................................................................... 19

Graphical results.................................................................................................... 21

Uf and Psi automatically ........................................................................................ 23

Façade profiles and other special geometries etc. ................................................ 24

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Preparing the CAD drawing 1. The DXF import into the DXF-Converter is optimised for DXF files from AutoCAD.

DXF file from other CAD solutions can be used too. But additional steps could be necessary.

2. 1 unit in AutoCAD should be 1 mm.

3. Only constructively necessary lines (delete hatches, dimensioning, inscriptions etc.)

4. No polylines, no blocks (AutoCAD command "xplode")

5. Move drawing to first quadrant (+x and +y) or set back to origin

6. Additionally it is useful to draw a rectangle around the section defining a layer of internal and also external air as well as the length of the panel or glazing. You can also already define within the drawing the areas of reduced radiation and convection in internal corners. All the geometry specialties descript in EN ISO 10077-2 might be easier to already do in AutoCAD instead of doing it in WinIso. Only advanced user of WinIso should do it there.

(sample dxf2.dxf)

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Converting the DXF drawing 1. Reasons for the convertion:

a. converting non orthogonal lines and circles into steps b. closing material contours c. reducing number of elements

2. The following suggestions are only exemplary. Depending on the target of the

calculation, the size of the section or the details of the section other steps might be necessary. The following steps are exemplarily for a PVC window section (the section will be installed with WinIso: dxf2.dxf)

3. Open DXF file with the DXF converter (windxf.exe or DXF converter in the main window of WinIso). Please pay attention that the drawing should be closed in the CAD software before to avoid file conflicts.

4. Edit curves (circles, arcs, curves etc.)

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5. Linking lines (this command is only necessary to ensure the correctness of the next step)

6. Apply important lines (this command is necessary to keep important lines on their position when using the next command)

7. Allign lines to raster (this command moves all lines which are shorter than defined before to raster. This reduces the number of elements.)

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8. Convert diagonal lines to stairs

9. Linking lines (this command is only necessary to ensure the correctness of the next step)

10. Apply important lines (this command is necessary to keep important lines on their position when using the next command)

11. Allign lines to raster (this command moves all lines which are shorter than defined before to raster. This reduces the number of elements.)

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12. Editing open lines

13. Linking lines

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14. Check number of elements Depending on the WinIso version you are using (Standard 500x500 or Professional 1000x1000) and the complexity of the section the number of elements after the conversion should be ca. 100x100 up to 400x400. On one side it is necessary to add additional elements later in the Editor for a correct calculation and on the other side a higher number of elements only increases the time for the calculation without a higher correctness of the results. To small and many elements can lead to problems with the convergence too. Instead of the conversion with 0,25 mm steps and raster a conversion with 0,50 mm or even 1,00 mm can be used too. For very big sections as wall-roof-joints for example even much bigger elements can be used. On the other side for very fine sections as IG spacer with very thin metal layers much smaller elements are necessary to avoid overlaying of lines/stairs.

15. Save file (maybe with a different file name)

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DXF conversion with a macro (batch file) The commands descript in the capture before can be put together in a batch file (macro) for a more effective conversion.

Macro editor �

Using a double click or the arrow button the commands on the left side of the editor can be put together to a batch file on the right side. With "Save" the batch file can be saved to be used later with the button "Load". With "Execute macro" the single commands defined before will be done automatically. When the conversion is done the editor will be closed and the converted file can be saved.

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Creating WinIso2D project and calculating the Uf-value according to EN ISO 10077-2

1. File/New… (only necessary in versions older than 5.0)

2. File/Import/Load dxf file… (The drawing already needs to be converted as descript in the capture before. Files saved with the DXF Converter only have one layer left, the Layer01. If an original drawing is already orthogonal layers can be switched off here (hatches, dimensioning etc.)

3. The number of elements should be far below the maximum number of the WinIso-Version you are using (500x500 bzw. 1000x1000)

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4. Choose cavity algorithm

The algorithm without "2004" only uses one equivalent conductivity for the air in a cavity, the algorithm with "2004" uses two different conductivities in x- and y-direction.)

Choose materials / Material database

On the right hand side of the material database are the materials (project materials) to be used in the current project. On the left hand side you find the global materials which are installed together with the software. The most common materials for windows, doors and facades you will find in the material group "2_EN ISO 10077-2". If you are using this materials the Word export automatically checks the conformity of the used materials with 10077-2. With a double click or using the arrow button the global materials can be put together for the current project. The materials ND (not defined) and ADIABAT (adiabatic boundary) are always to be found in the project material list.

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5. Fill CAD lines Always fill all solid materials first and than the boundaries. Keep the cavities as last.

a. Choose material from the pull-down-menu

b. select cell within a contour

c. push the F4 key (= Fill CAD lines)

d. …keep doing so with all solid materials

e. fill internal and external boundaries (F4 or F3)

6. Filling cavities with 10077-2 air with Edit/Assign material

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7. Switch off CAD lines and show edging (This helps to easier find small cells with wrong material etc.)

8. Close cavities with openings 0-2mm to the boundaries or to each other (Edit Bearbeiten/Separate cavities <=2mm (10077)) (this command is only available from version 5.0 and higher)

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9. In Version older than 5.0 the separating of cavities <= 2mm has to be done manually with a thin layer of a material with a low but not to low conductivity (PVC or EPDM)

10. Fill slightly ventilated cavities to internal or external air > 2mm and < 10 mm (depth > opening) with the material "air 10077-2 (Auto, SVC)". In versions older than 5.0 it has to be done as descript in the next point.

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11. ! Only versions older than 5.0! Calculate the equivalent conductivity for slightly ventilated cavities (2 mm, <10 mm, depth > opening)

a. Close cavity with solid material (e=0,9) and fill it with "air 10077-2 (Auto)"

b. Calculate the project

c. Open window "Info about cells…"

d. select a cell in the cavity

e. Read equivalent conductivity = 0,047 W/mK (if conductivity is different in x- and y-direction choose the one of the main heat flow direction or calculate the average of both)

f. Open material database

g. Choose any material and make a copy of it. Move the copied material into the project materials and click change. Rename it into for example SVC and change conductivity to a value twice as big as calculated before = 0,094 W/mK.

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h. Fill the created SVC material into the cavity and remove the solid

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12. Define geometry according to EN ISO 10077-2

a. Length of panel: 190 mm (measured from the edge of the frame not the gasket), (Change column width)

b. Depth of panel in frame: max. 15mm

c. Gap between frame and panel: min. 5mm

d. End of project (frame and pane): adiabatic or just end of section

e. If not already defined the areas with reduced radiation and convection in the drawing you need to define it now in WinIso

13. Define additional elements in areas with big columns or lines (panel etc.) Mark with your mouse an area over profile and panel and go to Edit/Automatically split

Choose "Splitting to x mm" and type the size of the additional elements, choose "Selection" and click OK. (The size of the elements should be defined that a further halving of the size is not relevantly influencing the result of the heat flow)

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14. Calculate: Calculate/Start with random temperatures or Attention! Watch convergence (max. 0,03mK and 0,03%, better 0,005mK and 0,005%)

15. Uf-calculation according to EN ISO 10077-2

a. f

PPD

f llUL

U∗−=

2

TQ

L D

∆=2

with: i. Q total heat flow W/m ii. L2D two-dimensional conductance W/mK iii. �T Temperature difference internal/external K iv. Uf Uf-value of the frame section according to 10077-2 W/m²K v. UP U-value of the panel W/m²K vi. lf width of the frame section (projected width) m vii. lP length of the panel from the edge of the frame section m

b. U-value panel: select cell in the panel (at Rsi = 0,13 m²K/W �

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c. Select a cell in the panel at the edge of the frame section (here on the right hand side of the frame section) � (gaskets and other will not taken into account)

The temperature difference, total heat flow, lengths right and left or above and below the selected cell will be automatically shown in the Uf-window.

d. Choose whether the frame is on the left hand or right hand side (or above or below the selected cell

e. Apply last measured U-value of the panel with "Apply"

f. Calculate Uf with the button "Calculate"

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Calculation of � (Psi, linear thermal transmittance) of IG spacer according to EN ISO 10077-2 1. The calculation of Psi works quite similar to the calculation of Uf but with the

original IG. The IG can be defined as a single WinIso project and imported into the frame. For the import you need to choose the far left cell on the top of the panel. The IG will be imported to the right and below from that cell.

2. Calculate: Calculate/Start with random temperatures or Attention! Watch convergence (max. 0,03mK and 0,03%, better 0,005mK and 0,005%)

3. ggD lUlfUfL ∗−∗−=Ψ 2

TQ

L D

∆=2

with: i. Q total heat flow W/m ii. L2D two-dimensional thermal conductance W/mK iii. �T Temperature difference internal/external K iv. Uf Uf-value of the frame section as calculated before v. Ug U-value of the IG W/m²K vi. lf width of the frame section (projected width) m vii. lg length of the IG measured from the frame edge m

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4. Calculate the Ug of the IG

5. Select a cell in the IG at the edge of the frame section �

6. Apply the last measured U-value (Ug) with "Apply"

7. Type in manually the Uf of the frame section as calculated before into the correct field (top/left or bottom/right)

8. Calculate Psi with the button "Calculate"

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Graphical results

materials

isothermal lines (blue = 10°C, red = 13°C)

temperatures To show the internal and external air white change the range of temperatures as shown below.

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heat flow (blow low, red high) used materials:

Material R (m²K/W)

T (°C) Q(gesamt) (W/m)

10077 konform

****ADIABAT**** 0,000 0,000 1 Luft außen 0,04, 0°C, 80% 0,040 0,000 X 1 Luft innen 0,13, 20°C, 50% 0,130 20,000 X 1 Luft innen 0,20, 20°C, 50% 0,200 20,000 X 1 Luft 10077-2 (Auto) X Luft 10077-2 (<=2mm) X 1 Luft 10077-2 (Auto, LBH) X 1 Kalibrierpaneel 0,035 X Material L

(W/mK) Mue 10077

konform 3 Alu (Si-Leg.) 160 160,000 X 4 Polypropylen 25% GF 0,250 X 5 EPDM 0,250 X 2 Float 1.0 1,000 X 90% Argon fest 0,027 X 6 Butyl 0,240 X 6 Polysulfid 0,400 X 6 Silicagel 0,130 X

Te = 0 °C Ti = 20 °C Rsi = 0,13 m²K/W Rsi = 0,20 m²K/W Rse = 0,04 m²K/W lf = 110 mm lg = 190 mm Ug = 1,1 W/m²K Uf = 3,2 W/m²K �g = 0,115 W/mK

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Uf and Psi automatically When using the functions Uf and Psi automatically it is not necessary to replace the IG with the calibrating panel. The software does that automatically. Just select a cell within the glass. The function Uf automatically is automatically calculating the Uf, the function Psi automatically is automatically calculating the Uf and than the Psi. Both functions do save an additional file with the calibrating panel. This file has the same path and name as the original file but the extension "_panel.f2d". The length of the panel or IG will be measured automatically from the end of the panel/IG to the first contact of the panel/IG with a solid material. So the lengths are not quite correct when gaskets or other parts of the frame run over the actual edge of the frame. This has to be changed manually in the calculation window or in the project itself.

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Façade profiles and other special geometries etc. When calculating frame sections with IGs on both sides of the section the steps are the same as descript before. But in the Uf or Psi calculation window the lengths and width of frame, panel and IG has to be typed in manually.

Please pay attention that the calculated Psi is the result for both spacers on each side.

The function Uf and Psi automatically is measuring the lengths correctly automatically.