Best Facade Best Practice for Double Skin Facades WP4: Simple Calculation Method
Overview on WP4: Simple Calculation Method Background: assessment of the thermal behaviour and energy-efficiency of naturally or mechanically ventilated double skin facades only possible by using (complex) simulation tools Goal: development of an assessment method: - integratable into assessment methods of the EPBD / harmonized with CEN standards - sufficient accuracy of thermal behaviour and energy performance - usable for construction guides Main work to do regarding the assessment method: - approximation of the airflow in the facade interspace - adaptation of the utilisation factor of the solar gains to different facade systems - comparison to results from simulations in different climatic regions
Overview on WP4: Simple Calculation Method Deliverables: (paper version + interactive usable internet tool), month 24 - D7: simple calculation method (module for the integration in the extended ISO 13790/EN 832) - D8: energy design guide for the assessment of the influence parameters of DSF in the early planning phase Contributions: - coordination + presentation of results to CEN: FhG-IBP - assistance in approximation of airflow + temperatures in the facade interspace: IWT, ULUND, BBRI - validation tasks (existing monitoring results), functional trend scenarios dependent on the external influence parameters (temperature, solar radiation, wind) to be integrated as rules of thumb where required, documentation of application of method at selected test examples: MAB, NKUA, DIMGLASS, ENTPE, ULUND, WSP, Skanska - provision of monitoring data of built examples: industry partners
Literature review A literature review was done, only some general data is available
Development of an EP calculation method A monthly based calculation approach, based on the concepts for glazed buffers in ISO EN 13790 will be developed. Existing simplifications from literature review will be used
The CEN Model
The DIN approach
The WIS approach www.windat.org
WIS/ Platzer DIN V 18599 Φ qi,e Φ qe,w Φ u I s I s Φ s,tr Φ abs,p Φ s,sd Φ s,u Φ s,opak Φ abs,u Φ u = Φ abs,u +Φ abs,p +Φ qe,w +Φ qi,e Φ u = Φ s,u - Φ s,tr - Φ s,opak The formula for ϑ u versus Φ u is the same in both approaches but not the calculation of Φ u
Φ u Φ qi,e Φ qe,w I s I s Φ s,tr Φ abs,p Φ s,sd Φ s,u Φ s,opak Φ abs,u Φ Φ abs, u = τ e, e A j α I Φ abs, p = τ e, e Ap α e, p j s I s U P R qi, e = Aw I s qi, e = Aw I s ( g e τ e, e ip ) Φ s, u = Aue g eff, ue FF, ue I Φ s, tr = FF, iu Aiu g eff, iu FF, ue τ e, ue s I s Φ qe, w = τ = τ e, e e, e A A w w F F F, w F, w I I s s q e, w (1 g w ρ ) w Φ s, opak = 0 Φ u = (ΦΦ abs,u +Φ abs,p +Φ qe,w +Φ qi,e ) F S F Ce F Fe Φ u = Φ s,u - Φ s,tr
Balancing of a zone Φ u Φ qi,e Φ qe,w I s I s Φ s,tr Φ abs,p Φ s,sd Φ s,u Φ s,opak Φ si Φ T,u Φ abs,u WIS/ Platzer DIN V 18599 Φ = (1 F ) F si u s in Φ u F Ce F Fe Φ u ΦT u = HT ui ( ϑu ϑ ),, i Φ sd = I v + τ F e, e Cp F α Fe e, p F Ce A p F s U ( F p Cw R pu g ) w F Fw A w Φ s, tr = I s τ e, ue FF, ue g eff, iu FF, iu Φ s, opak = 0 g a g A tot eff = FW FV min FS g iu + (1 a) g
Glazing outside: Glazing inside: Brüstung: A = 27,39 m³ A = 18,26 m³ A = 9,13 m³ g _I_ = 0,76 g _I_ = 0,54 α = 0,6 t e,e = 0,73 ρ e = 0,074 F Fe =F ue =0,95 g eff,sommer = 0,30; g eff,winter = 0,41 F Fw = F ui =0,81 g eff,sommer = 0,21 g eff,winter = 0,29 obstructions, shading, framing, dust is missing U P = 0,6W/m²K R Pu = 0,13 W/m²K Building elements in the gap: A = 27,39 m³, α = 0,4 Ansatz Dr. Platzer DIN V 18599 Φ abs,u Φ abs,p Φ qe,w Φ qi,e Φ u [W] Φ u [W] Φ s,tr Φ s,u Jan 479,87 18,72 248,98 49,30 517,97 463,69 178,72 642,41 Feb 543,86 21,21 282,18 55,88 587,03 525,52 202,55 728,07 Mrz 799,79 31,19 414,97 82,17 863,28 772,82 297,87 1.070,69 Apr 999,74 38,99 518,71 102,71 1.079,10 699,80 269,73 969,52 Mai 1.015,73 39,61 527,01 104,36 1.096,36 710,99 274,04 985,04 Jun 1.103,71 43,04 572,66 113,39 1.191,32 772,58 297,78 1.070,35 Jul 935,75 36,49 485,51 96,14 1.010,03 655,01 252,46 907,47 Aug 783,79 30,57 406,67 80,53 846,01 548,64 211,47 760,11 Sep 783,79 30,57 406,67 80,53 846,01 548,64 211,47 760,11 Okt 655,83 25,58 340,27 67,38 707,89 633,71 244,26 877,97 Nov 319,92 12,48 165,99 32,87 345,31 309,13 119,15 428,28 Dez 271,93 10,61 141,09 27,94 293,51 262,76 101,28 364,04
ϑ U = Φ U + ϑ ( H e H T, ue T, ue + V, ue ) + ϑi ( T, iu ) + H H V, ue + H T, iu H Dr. Platzer: H v,ue = 2 0,34 n V n Sommer = 2 h -1 n Winter = 30 h -1 DIN V 18599: H v,ue = 0,34 n ue V u n ue = 10 h -1 Temperatur Platzer DIN V 18599 DIN V 18599 ϑ i ϑ e Φ u ϑ U Φ s,u ϑ U Φ s,u ϑ U [ C] [ C] [W] [ C] [W] [ C] [W] [ C] Jan 19,5-1,3 517,97 1,2 463,69 5,3 517,97 5,6 Feb 19,7 0,6 587,03 3,1 525,52 7,2 587,03 7,6 Mrz 19,9 4,1 863,28 6,9 772,82 11,4 863,28 11,9 Apr 20,4 9,5 1.079,10 19,6 699,80 15,4 1.079,10 17,5 Mai 20,5 12,9 1.096,36 22,3 710,99 18,2 1.096,36 20,3 Jun 20,7 15,7 1.191,32 25,1 772,58 20,9 1.191,32 23,1 Jul 20,8 18,0 1.010,03 25,6 655,01 22,1 1.010,03 24,0 Aug 20,6 18,3 846,01 24,7 548,64 21,7 846,01 23,3 Sep 20,6 14,4 846,01 21,8 548,64 18,6 846,01 20,2 Okt 20,3 9,1 707,89 11,3 633,71 14,7 707,89 15,1 Nov 19,9 4,7 345,31 6,4 309,13 9,4 345,31 9,6 Dez 19,7 1,3 293,51 3,2 262,76 6,4 293,51 6,5
Basic measured datas from VERU
Validation 100 90 80 70 Control criteria ventilation wings: ϑ outside < 10 C: Wings closed ϑ outside > 10 C: Wings opened Öffnungszeiten Lüftungsklappen GDF Öffnungszeit [%] 60 50 40 30 20 10 0 Jan Feb Mrz April Mai Jun Jul Aug Sept Okt Nov Validationperiode May 2005 to March 2006 Dez
Validation Comparison of the measured daily mean values of air temperatures in the GDF gap versus the outside 30 20 Außenluft GDF Temperatur [ C] 10 0 Summer mode -10 Winter mode -20 0 30 60 90 120 150 180 210 240 270 300 Zeit [d] Investigation period May 2005 to March 2006
Validation Monthly mean values of outside air temperature and air temperature in the gap of the GDF (measurements versus DIN V 18599) Messung 18599 n = 10 h -1 n win =30h -1, n Som =2h -1 n win=0h -1, n Som =15h -1 ϑ e ϑu Φu ϑu ϑu ϑu [ C] [ C] [W] [ C] [ C] [ C] Jan -6,20 4,90 463,69 1,4-1,8 5,7 Feb -3,10 7,00 525,52 4,3 1,2 8,4 Mrz -0,10 9,70 772,82 8,0 4,6 12,6 Apr 699,80 15,4 17,8 14,5 Mai 12,30 17,20 710,99 17,8 20,0 16,9 Jun 16,30 19,10 772,58 21,3 23,4 20,6 Jul 16,70 18,90 655,01 21,0 22,8 20,4 Aug 14,50 16,80 548,64 18,7 20,4 18,0 Sep 13,80 17,10 548,64 18,1 19,8 17,4 Okt 8,80 13,90 633,71 14,5 12,1 17,7 Nov 1,60 9,00 309,13 6,9 4,7 9,9 Dez -2,60 5,70 262,76 3,3 0,8 6,5
Main results so far - The DIN/CEN approach fits well the measured data if ventilation rates are known - few information on ventilation rates is available - project investigations has to be concentrated on this issue - some extra validation for different facades should be done (WIS versus DIN/CEN)
Planned validation (WIS vs. DIN/CEN) Monthly mean values of air temperature in the gap of the GDF s
Rough estimations from experiences VERU - monthly mean space temperature 3 (Summer) to 10 K (Winter) above monthly mean outside temperature - maximal space temperature appr. 15 to 20 K above max. outside temperature - minimum space temperature slightly above minimum outside temperature Baden - Autumm periode: mean space temperature 2 to 3 K above mean outside temperature, mean air velocity in the space appr. 0,2 m/s - Summer periods: mean space temperature 4 to 8 K above mean outside temperature, mean air velocity in the space appr. 0,3 to 0,4 m/s
Rough estimations from experiences Müller et. alli: - monthly mean space temperature and air velocity not recorded - maximal space temperature appr. 15 to 20 K above max. outside temperature - minimum space temperature not recorded RWE-Tower Essen Victoria Versicherung Düsseldorf 55 45 50 45 40 Temperatur [ C] 40 35 30 25 Te_mess Tg_mess Ti_mess Tg_model Temperatur [ C] 35 30 25 20 15 10 6 9 12 15 18 Uhrzeit [h] 20 15 Te_mess Tg_mess Ti_mess Tg_model 6 9 12 15 18 Uhrzeit [h]
Basic data from the PhD-work Ziller 150 bis 250 h -1 2 bis 5 K Approximation (per m length): 3m height x 0,5 m depth = 1,5 m³ 0,3 m/s x 0,5 m² = 0,15 m³/s Air change rate: 0,15/1,5 = 0,1 s -1 = 360 h -1
Other existing useful basic datas and contributions - BBRI: mechanical ventilated DSF and natural ventilated multi-storey DSF - Aalborg university: measurements at testing facility provided by ULUND - IWT: school in Baden sporadic measurements (already analysed) - Who is responsible for an approximation approach of the air flow rate in the gap (ULUND or IWT)??? - BBRI and IBP will work on some validations (CEN vs. WIS)
Energy design guide Innovative building concepts should be optimized by an integrated planning process. High performance facades in combination with regenerative energy service systems results in low demands
Additional to the heating & cooling calculation approach we need an integration of (day)-lighting effects P(t) Q = t Ende P () t dt P max t Anfang t 1 t äq t 2 t Q = P max t äq
Calculations approach Q Licht = N [ pn [ A TL,n (t n + t eff, Nacht, n ) + A KTL,n (t n + t eff, Nacht, n )] + Q n ] eff, Tag, eff, Tag, KTL, par, n = 1 Installed power Daylighthours incl. Control system Presens sensor Parasitary effects Daylight zone Zone without daylight influence
Daylighting indicated by an effective operation time Q Licht = N [ pn [ A TL,n (t eff,tag,n + t n ) + A KTL,n (t eff,tag,ktl,n + t n )] + Qpar,n ] eff,nacht, eff,nacht, n= 1 t t eff, Tag, KTL, eff, Tag, TL, n n = = t t Tag,n Tag,n F F TL,n Pr ä,n F Pr ä,n F Pr ä,n = 1 C A,n C Pr ä,kon,n Absensefractionin thezone Effectiveness of an absense control system t eff, Nacht, n F = 1 C C = tnacht,n FPr ä,n TL,n TL,Vers,n TL,kon, n Daylight delivery factor Factor of effectiveness for the control system
The interactive internet tool (an approach) E:\Hans\Fassadenauslegungstool\index.html
Expected contributions According to the contract: - coordination + presentation of results to CEN: FhG-IBP - assistance in approximation of airflow + temperatures in the facade interspace: IWT, ULUND, BBRI - validation tasks (existing monitoring results), functional trend scenarios dependent on the external influence parameters (temperature, solar radiation, wind) to be integrated as rules of thumb where required, documentation of application of method at selected test examples: MAB, NKUA, ISQ, DIMGLASS, ENTPE, ULUND, WSP, Skanska - provision of monitoring data of built examples: industry partners Manpower (Ph): IBP 600; ISQ 600; NKUA 350; LASH 350; BBRI 350; IWT 300 ULUND 150; MCE 100; Dimglass 50; WSP 50; SKANSKA 50 Themes: IBP procedure; ITW & ULUND approximation airflow; BBRI validation ISQ & NKUA & LASH design guide; industry partners informations