1. Tools for Integrated Design ID seminar 24-26 October Christian Hviid Industrial PhD-student Birch & Krogboe

2. Agenda Tools package LightCalc Technicalities Glazing and shading input from WIS Combined BuildingCalc and LightCalc Technicalities Controls: daylight, glare (blænding), temperature iDbuild Parameter variations Tool for integrated design Live show

3. Complexity Room

4. Tool development BuildingCalcLightCalc Thermal simulation Daylight simulation BuildingCalc + LightCalc iDbuild Integrated Design of Buildings

5. Development objectives Room level Quick and intuitive input Accuracy comparable with much more advanced programs High calculation speed Facilitates consequence-guided design process

6. Look and feel

7. LightCalc Capabilities Daylight on room level Standard overcast sky or weather data Accepts material input from user or from Window Information System (WIS) database European glazing and shading products A quick tool for daylight design Limitations One room model, one window

8. Skies Sky subdivision Up-side down sky for ground reflectance The Perez sky model is a mix of clear, intermediate, and overcast sky created directly from weather data.

9. Technicalities L: patch luminance (lm/m 2 Sr) ΔS: solid angle (Sr) ξ : incidence angle σ: visible proportion of sky patch τ: transmittance I: direct normal irradiance (W/m2) η: beam luminous efficacy (lm/W) Ray-tracing Radiosity B: radiosity E: emitted energy R: reflectance F: form factor

10. WIS input

11. WIS input 2 WIS report For 10 slat angles – 10 reports

12. New database entry

13. Glazing and shading database

14. Case

15. Daylight factor 10000 lux outside and 200 lux inside is a DF 2% A standard for measuring daylight friendly design

16. LightCalc – overcast day Calculation time: ~1min on Pentium M 1.8Ghz With overhang Without overhang

17. Validation Relative error: ~30%

18. LightCalc – sunny day Without blinds With blinds at cut-off angle

19. Validation Relative error: ~20% Relative error: ~10%

20. BuildingCalc + LightCalc Capabilities Energy consumption on room level Separate ventilation, heating, cooling, lighting Indoor thermal climate Hourly values for daylight Multiple possible system controls daylight, glare, temperature, natural ventilation A tool for integrated daylight and thermal design Limitations One room model, one window

21. Technicalities Thermal node model Temp. in the wall Wall surface temp. Air temp. Ext. temp. Heat gain to air Heat gain to building structure

22. Shading control Overhang, blinds, screens Slat angle, β Outside Inside Slat distance, d Slat width, w Profile angle, p Cut-off angle

23. Glare control Glare is almost directly related to the amount of daylight the occupant receives in the eye A threshold of 20% means that 20% will be disturbed

24. Control flow Is it too hot and/or too much light? Shading is lowered Blinds are adjusted to cut off angle Simulation hour t yes Is it still too hot? Simulation hour t+1 yes no Excess temperatures If specified: 1.Windows are opened 2.Ventilation is increased 3.Cooling is started

25. BC+LC results

27. Hourly values 1st week of January Integrated values

28. Validation

29. iDbuild Capabilities Systematized parameter variations using BC+LC Presentation of variation results Limitations Still too slow

30. Parameter 2 Parameter 1 Method – setup Variation 1 Variation 2 Reference Parameter 3 Variation 1 Variation 2 Reference Lower value Higher valueReference value No of simulations: 1 3 5 Reference systems Var.1 systems Var.2 systems

31. Method – work flow Decide on a reference Decide on which parameters we would like to change Enter values for variation 1 and variation 2 Click simulate Evaluate results Repeat with new reference if desired

32. Method – results Results Param.1Param.2Param.3 Var.1 Refer. Var.2 Var.1Var.2 Refer. One parameter variation

33. Case

34. 4x6x3 m room with 2 persons Window height (above working plane) Shading 1.2m 2.0m 1.6m Dbl glz Variation 1 Variation 2Reference Dbl glz w/ ext blinds Dbl glz w/ AntiSun Cooling Mechanical Night cooling No cooling

35. Evaluation settings What should we measure the results up against? Winter: 21-23C Summer: 23.5-25.5C 1.5 L/s pr m2

36. Window parameters

37. Cooling parameters Mechanical cooling

38. Results – glazings Clr dbl glz Ext blinds AntiSun

39. Energy and comfort

40. Results – window height

41. Results – cooling Mech. None Night

42. Energy and comfort Cooling is required in winter to keep temperature below 23C…

43. Final results

44. Conclusion on case For the specified indoor climate parameters: Use external shading Use window height of 1.2m And handle the overheating with night cooling The sum ≠ one parameter + another param. Achieving low-energy class 2 for offices is not easy, but this is the only way for no extra costs… Is a temperature range of 2°C for indoor class I not too strict with regards to energy?

45. Limitations Mixing multiple parameter variations requires multiple references If the effect of two variations are opposite, it is invisible before another reference has been made System variations have to be made separated from the rest of the variations ( in line for changes… )

46. Additional info Prerequisites Installation of runtime libraries ~100MB Or Matlab technical programming language We are now in version 2.5.1 but are constantly improving Version 2.6 is expected to be faster