DeST 8 DeST Building environment design simulation software DeST(8): combined simulation of naturaland mechanical ventilation By Zhang Ye, Zhang Yufeng, Song Fangting, Ya Da and Jiang Yi Abstract It is very important to understand the building ventilation conditions, because ventilation and infiltration affect building environment directly and instantly. Ventilation in buildings includes natural ventilation and mechanical ventilation. They are essentially the same and often occur at the same time, so need to be considered together instead of separately. Explicates the uniform network model and the solving method in the building simulation tool - DeST, which is developed from the multizone airflow network model and the pipe network model. Provides mathematical models for commonly used building components and achieves coupled simulation of natural ventilation and mechanical ventilation. Gives some case studies to illustrate how to solve the problems in designing building ventilation systems by DeST and indicates the significance of using simulation tools for ventilation design. Keyword natural ventilationmechanical ventilationairflow network modelstatic pressure 1979 100084 (0106789761 zhangye0@mails.tsinghua.edu.cn 004-1-31 005-01-05-1 -
- - 1 1.1 [1~] 30 DeST airflow model thermal model 50 [3] 1.
Tjbaou [4] DeST.1 0 [5] a)comis [6~7] b)contam [8] c)breeze [9] d)natvent [10] e)passport Plus [11] f)aiolos [1] a),b),c) d) e)f) Kendrick sequential coupling [13] [14] Hensen ping-pangonion [15] 1-3 -
onion 1 EnergyPlus COMIS COMIS [16] [16] ping-pang TRNSYS COMIS TRNSYS COMIS-TRNSYS TYPE 157 TYPE 56 onion [17] s 1 min 1 h [18]. a) b) CONTAM [8] CONTAM DOE- [19] 3 3.1 DeST DeST - 4 -
- 5 - a) b) 3
3 3 A [0] N + 1 B N B A + 1 bj ni ni aij = 1 bj ni ni 0 b n j i A n A N i gi = q i i g i i q ρ ( av av 1 1) Z p1 p = + ht hp + ρgdz 0-6 -
p 1 p ρ v h t h p hp a 1 a Z a ρu d 3 u A d u A a = = 3 ρv v da va d u v a a DeST CFD 3 1 AG = Q T AP = DH H = SGG +? gz -DH -? P v A G kg/sq - 7 -
P PaH PaDH PaS P PaZ r kg/m 3 v g P v i ρ p vi = cos( αi) ai vi vi cos( αi1) ai1 vi1 v i1 4 v v α i1 α i 0 i1 i 90 a i1 a i Q = 0 5 Q 5-8 -
Z DeST 3. B N + 1 A N B A A A A= [, ] A A t l t G l l G A A A Q 5 I 0 l = Gl + S S t = l S Gt G = G l G G G DH t DH = DH l pvt Zt pv = Z = p vl Zl rt r = rl t = l 3 A p = S G G + r gz DH p T t t t t t t t vt A p = S G G + r gz DH p T l l l l l l l vl AA ( S G G + r gz DH p ) = SG G + r gz DH p T l t t t t t t vt l l l l l l vl T B =, f A A I l B f ( B N) B Bf ( SG G+ r gz DH pv) = 0 6 5 G 6 B N B N 6 S S = S( G) l - 9 -
F = Bf ( SG G+ r gz DH p ) G A A l T 5 = = Bf Gl I F S DH ( pv) = Bf( SG + G G ) B G G G G l v S1 S1 S1 G1 sign( G1) G sign( G) GB sign( GB) G1 G G B S S S S G sign( G ) G sign( G ) G sign( G ) 1 1 B B G1 G G G G = B G SB SB SB G1 sign( G1) G sign( G) GB sign( GB) G1 G G B sign( G j ) j l T f F G 6 3.3.1 p = SG 7 S = SG ( ) 8 G 7 8 DeST S - 10 -
DeST 7 S a (a) l ρv p = λ d 7 S λl S = 9 dρ A λ l ρ d ' ε 68 0.5 λ = 0.11( + ) d Re λ = λ + λ < ' ' λ = λ λ ' ' 0.85 0.008 0.018 10 0.018 ε Re = vd ν v ν 101.3 kpa 0 1. kg/m 3 ν =15.06 10-6 m /s (b) ρv p = ζ Pa 7 ζ S = 11 ρa ζ ζ ζ T - 11 -
6 6 I 1 1 1 6 T 6 II ρ v3 v3 l ρ v3 v3 p1 p3 = ζ pv 13 + λ 1 d ζ p 1, p3 1,3 v 3 3 λ l ρ d ρ v v 1 p 3 3 v13 = 1 l ρ p1 p3 = ( ζ + 1 + λ ) d v v 3 3 ζ ζ p > p v > 1 3 3 0 ζ 7-1 -
[1] S 7 CQ kgpa n G = C ( p) n 13 Q 1 1 n n Q S = C G /s n n 0.5 1 n 0.5 n 1 n 0.6 0.7 [8] GB 7107 86 DeST C n Q S 7 p G = CA d 15 ρ ρ S = ( CA) d A DeST C d Cd [~4] C 0.65 C 0.8 [8] Per Heiselberg d C 1 [5] d - 13 - d
AchakjiTamura [8] 17 Ae 0.6 S G = Ae 0.6 p 17 1.39 S = 18 A e Ae As h d A e Ae = As(0.089 h)(1.0 0.14 d) Ae = As(0.083 h)(1.0 0.4 d) d 01 /m DeST As h d b [6] DeST S S S 9( g ρ ) ( WC ) ρ = 8 d mg a 1/3 ( G ) b ( g ρ ) 8 ( ) Hg ρ sign 9 = b 4/3 Gb Gb WCd ρm 19 1/3 0 W, H C d ρ m ρ G a, Gb G = G + G 7 a b - 14 -
p p p= Sa Ga Ga p= Sb Gb Gb DeST Hensen onion DeST onion sequential 4 4.1 DeST 15 W/m 7 13 4 m 40 mm - 15 -
7 1 m 1 5 8 4 1. 0.5 0.5 4 /W/m K 40 0.564 1.515 0.81 3.100 3 1 0.5 h -1 3 19:00 7:00 5 1 10 1 456 4 1 h / = 5 57 730 >30 180 894 543 614 340 A 67 615 699 1371 719 B 419 680 637 1336 599 5 h / = 5 57 730 >30 180 894 543 614 340 A 613 879 994 105 160 B 67 899 106 995 14 6 3 h / = 5 57 730 >30 180 894 543 614 340-16 -
A 70 948 941 109 33 B 693 938 93 107 36 0.5 h -1 30 500 h 30 150 h 30 50 h 6 155 89 8 A 9 B 89 30 35 7 30-17 -
4. 4..1 10 1 1 1 11 1 1 1 10 11 4 5 6 7 8 1 3 9 10 11 1 1 1 m1m 4mm DeST 7 7 1 3 4 5 6 7 8 9 10 11 1 /mm 50 50 50 50 50 500 400 50 50 50 50 30 /mm 00 00 00 00 00 400 50 00 00 00 00 50-18 -
/m 5 5 5 1 1 5 5 5 1 1 5 5 8 p = 5 10 G 3.38 10 G+ 00 8910 8 1 3 4 5 9 10 m 3 378 656 717 430 436 864 979 /h 9 345 31-33 161-151 -3-184 -0-41 1 9 11 10 Pa 8.7 6.0 13.4-1.9-1.7 4..4 13 1 3 1 3-19 -
13 14 (m 3 /h) 3500 3000 500 000 1500 1000 500 0 1 3 4 5 6 7 8 9 10 11 1 13 14 14 p G G 8 = 5 10 3.38 10 + 00 1516 4000 3000 (m 3 /h) 000 1000 0 1 3 4 5 6 7 8 9 10 11 1 13 14 15-0 -
(Pa) 0 - -4 1 3 4 5 6 7 8 9 10 11 1 13 14-6 -8 16 1 15 16 4..4 17 17 1 17 p = G G+ 8.4968 10 1.1768 10 984.9 η = 6.5898 10 8 G + 3.57594 10 3 G + 33.6439-1 -
10 h -1 10 h -1 17 1 35000 (m 3 /h) 30000 5000 0000 15000 10000 5000 0 1 1001 001 3001 4001 5001 6001 7001 8001 18 1919 0 1 17 (Pa) 700 600 500 400 300 00 100 0 0 5000 10000 15000 0000 5000 30000 35000 m 3 /h 1 19 - -
(kwh) 35000 30000 5000 0000 15000 10000 5000 0 4058 6133 7174 33009 1 0 5 1 James W Axley. Residential passive ventilation systems: evaluation and design. AIVC Technical Note 54.. 00,0(3) 3., 004,34(9) 4. 000(4) 5 Musser A M. Multizone modeling as an indoor air quality design tool. Health Building, 000() :455~460 6 Annex 3 1997a, COMIS 3.0 with IISiBat User Manual, 31st October 1997, IEAECBCS Annex 3, Multizone Air Flow Modelling 7 Helmut E Feustel. COMIS An International Multizone Air-Flow and Contaminant Transport - 3 -
Model, LBNL-418 8Dols W S, Walton G N.. CONTAMW 1.0 User Mannual. NISTIR 6476 9 BRE.BREEZE 6.0f User Manual. Building Research Establishment, Watford,UK,1994 10 Svensson C. The NatVent Programme 1.0 User's Guide. J&W Consulting Engineers, Malmö, Sweden,1998 11 Balaras C A, Alvarez S. Passport Plus Version.1 User s Manual.University of Athens, Greece, 1995 1 Allard F. Natural Ventilation in Buildings: A Design Handbook. James& James, London, UK, 1998 13 Kendrick J, An overview of combined modelling of heat transport and ai rmovement, AIVC Technical Note 40,1993 14 Hensen J L M. Modelling coupled heat and airflow: ping pong versus onions. Proceedings of 16th AIVC Conference, 1995, 1. 53-6 15 Malcolm Orme.Applicable models for air infiltration and ventilation calculations. AIVC Technical Note 51,1999 16 Sahlin Per. On the effects of decoupling airflow and heat balance in building simulation models. ASHRAE Trans, 003, 109().788-800 17 Haasa A, Weber A. COMIS v3.1 simulation environment for multizone air flow and pollutant transport modeling. Energy and Buildings, 00 (34): 873 88 18,,,. DeST 1 DeST, 00434748 19 DOE- Engineers Manual. Version. 1A. 198 0.. 1993.1-14 1.. 1994.65 ASHRAE. ASHRAE Handbook Fundamentals001 3,. 1986 4Allard F, Haghighat F.. Airflow through large openings in buildings. Technical Report of IEA/ECB-Annex 0: Air Flow Patterns Within Buildings, CH1015 Lausanne, Switzerland, 199 5Heiselberg Per. Characteristics of airflow from open windows. Building and Environment 001 (36) 859-869 6 Allard F, Dorer V B, Feustel H E, et al.fundamentals of the Multizone Air Flow Model - COMIS, AIVC Technical Note 9, 1990-4 -