HEAT FLUX MEASUREMENT OF URBAN BOUNDARY LAYERS IN KYOTO CITY AND ITS PREDICTION BY CFD SIMULATION

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1 EAT FLUX MEASUREMENT OF URBAN BOUNDARY LAYERS IN KYOTO CITY AND ITS PREDICTION BY CFD SIMULATION Kazuya Takahash 1, arunor Yoshda 2, Yuzo Tanaka 3, Norko Aoake 1 and Fuln Wang 1 Eghh Inernaonal IBPSA Conference Endhoven, Neherlands Augus 11-14, 23 1 raduae Suden, Dep. of Urban and Envronmenal Eng., Faculy of Eng., Kyoo Unversy 2 Prof., Dep. of Urban and Envronmenal Eng., Faculy of Eng., Kyoo Unversy, Dr.Eng. 3 Yamaake Corporaon, M.Eng. ABSTRACT In he summer of 22, measuremens were smulaneously performed o nvesgae he characerscs of hea flow n urban areas a hree locaons n Kyoo cy: 1) a commercal urban area mxed wh low-rse radonal resdenal buldngs ha represens he urban area of Kyoo, 2) an unversy campus area wh a lo of green zones, and 3) a plaza covered wh a concree slab whch was used as a reference pon of measuremen. ea flux of boundary layer over he hree locaons and he surface emperaures of buldng walls and srees were measured o nvesgae he urban hermal envronmen. For he analyss, a new smulaon code was developed by combnng unseady sae hea conducon of buldng walls and grounds, radaon hea exchange beween hem, and arflow by CFD (Compuaonal Flud Dynamcs). By usng hs code, he hermal envronmen of he urban areas such as ar emperaure, humdy, wnd velocy, and boundary layer hea flux was predced and compared wh he measured resuls. I was found ha hs model could predc he real hermal envronmen of he urban area. Usng hs code, he effec of addonal green on roofs and grounds can be nvesgaed n order o mgae urban hea sland and o mprove urban hermal envronmen a he sree level. INTRODUCTION I s a well-known fac ha he urban ar emperaure s gradually rsng n all ces and some effecve measures are needed o mgae. Several facors are repored o be he cause of he emperaure rse, such as dmnshng of green area, low wnd velocy due o hgh buldng densy and change of sree surface coang maerals. owever urban plannng based on he predcon of urban envronmen ncorporang he effecs of hese facors s under developmen (Wllamson e al., 21). A lo of researches have been performed on he measuremen and he analyss of urban envronmen, however, here are few researches ha compare measured and smulaed hea flux over urban areas and smulaneously measured hermal envronmens of several areas wh dfferen opographcal feaures. Such comparave measuremen and smulaon mehod enable he analyss of he facors ha nfluence he urban envronmen. In addon here are many researches regardng urban hermal envronmen smulaon, however, here are few researches n predcng by combnng 3-dmensonal CFD smulaon model and unseady sae hea conducon of buldng walls and grounds. Moreover few of hem compared he smulaed resuls wh he measured resuls and verfed smulaon accuracy (arayama e al., 22). The purpose of hs research s: 1) o clarfy he nfluence of local opologcal feaures on urban emperaure and humdy: 2) o compare sensble and laen hea flux characerscs of he urban areas wh dfferen amoun of bul and green area: and 3) o predc urban hermal envronmen by developng a new numercal smulaon model combnng ar flow and emperaure calculaon by CFD and ransen hea conducon calculaon of buldngs and grounds. MEASUREMENT OF EAT FLUX, TEMPERATURE AND UMIDITY We measured he sensble hea flux and he laen hea flux ranspored from he urban surface o he upper amosphere, and he emperaure of buldngs walls and srees a hree ypcal ses. The frs se s a cenral par of Kyoo cy (Se U) whch s brslng wh medum hegh commercal buldngs manly. The second se s a unversy campus (Se C) wh much greenery such as a green cour, and a hll covered wh ample green, called M. Yoshda Yama, s closely locaed easward. The hrd se s a cy-hall plaza (Se R) covered wh concree pavemen and s used as a reference measurng se for he presen and fuure analyss. Turbulen sensble and laen hea fluxes were calculaed based on eddy correlaon mehod, namely by he followng equaons (Tukamoo e al.,). = ρcwt ' ' (1) P l E = Lw' Rq ' (2)

2 U2 U1 U4 Un1 U3 Un3 n c Un2 s Us1 Us2 Us3 Se U Se R U5 U6 measured pon :hea flux m 5m 1m (Un1 o 3):emperaure, humdy(norh pavemen) N (Us1 o 3):emperaure, humdy(souh pavemen) (n,s,c,r):ground surface emperaureground Fgure 1 Map of Se U and he vew of he conducon se wh a crane Cn2 Cn1 N playground Cn3 A Cg1 Cg3 Cg2 Se C Cg4 Cn6 Cn4 Cn5 measured pon :hea flux m 5m 1m (Cn1 o 6):emperaure, humdy(far from rees) (Cg1 o 4):emperaure, humdy(near rees n he couryard) Fgure 2 Map of Se C and he vew of he campus couryard The wnd velocy flucuaon w ' and emperaure flucuaon T ' were measured by a hree-dmensonal ulrasonc anemomeer and humdy flucuaon q ' by an nfrared absorpon hygromeer. These values are defned as he flucuaons around he average value of each varable, whch was obaned by averagng recorded daa of 6 mnues. The measurng nsrumens were hanged by a crane rased on a buldng consrucon se. Amospherc emperaure and humdy nsde he ses were measured a he hegh of 1.5m and he surface emperaure of buldng walls and srees were measured by a handy radomerc hermomeer. Boh measuremens were carred ou manually by movng around he ses. The measuremens were conduced from 1: o16: on July 21s and 28h, 22. The measuremen pons of Se U and Se R are shown n Fgure 1, he measuremen pons of Se C are shown n Fgure 2. ea flux Each se s hea flux of July 21s and July 28h are shown n Fgure 3 and 4. On boh days, he sensble hea flux of Se U s 15 o 3W/m 2 and s abou 4% o 5% of he ne radaon. The laen hea flux of Se U s whn he range of -5 o 5W/m 2 and s average s approxmaely zero. We defne he ground surface hea flux = - - l E, whch s he resul of ne radaon subraced by sensble hea flux and laen hea flux l E. s abou 4% o 6% of he ne radaon n any perod. Wh respec o Se C, he sensble hea s abou 1 o 15W/m 2 on July 21s when he ne radaon s small and abou 15 o 2W/m 2 on July 28h when he ne radaon s large. The sensble hea flux of Se C s abou 3% of he ne radaon of each day, and s abou 5 o 1W/m 2 smaller han ha of Se U. The laen hea flux l E of Se C s 5 o

3 15W/m 2 and s abou 1W/m 2 larger han ha of Se U. The reason for hese phenomena can be he nfluence of he greens surroundng Se C and hs assumpon wll be valdaed by CFD smulaon laer n secon 3. The rao of, l E and on July 21s and July 28h o he ne radaon from 1: o 16: s shown n Fgure 5 and Fgure 6. The rao of urbulen hea flux, whch s he sum of and l E, o he ne radaon of Se U and Se C s abou 5% on boh days. The urbulen hea flux rao of Se R s abou 2%, whch s much smaller han ha of Se U and Se C. The rao of laen hea flux o he ne radaon of Se C s abou 2%, and he laen hea flux rao of Se U and Se R are abou zero. Thus, we can conclude from he measuremen ha he reason for lle laen hea flux on Se U and Se R s due o less green. Temperaure dsrbuon Fgure 7 and 8 show he average ar emperaure of several measuremen pons, whch are 1.5m above he ground of Se U and Se C, on July 21s and 28h. In addon he average values of hese emperaures from 1: o 16: are also shown n hese fgures. We defned T u as he average ar emperaure of sx measuremen pons on Se U, T c, g as he average emperaure of pons Cg1 o Cg4 on he par of Se C ha are close o couryard rees, and T c, n as he average emperaure of pons Cn1 o Cn6 on he par of Se C ha are apar from he rees. The average T c, n from 1: o 16: s.2ºc lower han ha of T u on July 21s and s.9ºc lower han ha of T u on July 28h. The emperaure dfference s greaer on July 21s han ha on 28h. The wnd on July 21s was from he souh where no much green area exss and on July 28h was from he eas where he green hll exss. Therefore he nfluence of green area on July 28h s greaer han ha on July 21s and hs mgh be he reason of he dfference. The average of T c, g from 1: o 16: s smaller han ha of T u on boh days, and he emperaure dfference s smlar for boh days. The reason of hs smlary can be due o he assumpon ha green area domnaes he emperaure close o self. 8 Se U Se R Se C Daa loss 1-1 Fgure 3 ea flux componens (July 21) 8 7 Se U Se C Fgure 4 ea flux componens (July 28) 1% 1% 8 Se R % 6% 4% 2% % Se U Se C Se R Fgure 5 Average rao of hea flux componens o ne radaon (July 21) 8% 6% 4% 2% % Se U Se C Se R Fgure 6 Average rao of hea flux componens o ne radaon (July 28)

4 Fgure 9 shows he average ar emperaure of norh and souh sde of pavemen on Se U. (The norh sde emperaure s he average of pon Un1 o 3 and he souh sde s he average of pon Us1 o 3.) The norh sde receves he sunshne and he souh s n he shade. owever, he maxmum ar emperaure dfference of hese wo emperaures s only 1ºC. The reason can be ha hs man sree s wde and open o he sky and ar of boh sdes s mxed easly whn he urban canyon and wh he upper amosphere as well. In secon 3 we wll verfy wheher hese hypoheses are verfed or no by CFD smulaon. CFD SIMULATION In hs secon, we predc hea flux and dsrbuon of ar emperaure and humdy of Se U and Se C usng CFD smulaon and usng measured surface emperaure as boundary condons. Confguraons and szes of urban buldngs are modeled smlar o he real ones as much as possble. The calculaon resuls were compared wh he measuremen resuls and he smulaon accuracy was checked. Models Ths CFD smulaon uses he k-ε hree-dmensonal urbulen flow model mproved by Launder and Kao. ρ = cons. (3) u = x 1: Se U Se C(far from rees) Se C(near rees) 11: 12: 13: 14: Fgure 7 Ar emperaures of Se U and C (July 21) ρu ρuu P u j + = + µ ρg ( T T ) o x x x x 15: j j j (4) (5) ρct uct. p p T + = K + q (6) x x x j j j We assume he flud o be ncompressble (equaon-3), and solve he smulaneous equaons of conservaon laws of mass (equaon-4), momenum (equaon-5), and energy (equaon-6). We make pressure correcon usng he SIMPLE mehod. We evaluae generaon of waer vapor E due o ranspraon by rees on Se C (equaon-7), whch s he shaded par of Fgure 2 and wh a green hll n he eas (no shown). The hea absorpon by rees ranspraon s calculaed by he equaon (8) 16: average : 11: 12: 13: Fgure 8 Ar emperaures of Se U and C (July 28) (a) (b) (c) Se U Se C(far from rees) Se C(near rees) 14: 15: 16: average (Yoshda, S. e al.,). E = avnes = avnbaw( fa fs) (7) l E = LE (8) The leaf area densy s aken as he average of keyak (a Japanese ree) and camphor ree. Moreover, ar ressance by rees s also evaluaed by addng he erm (9) o he momenum equaon (5) and urbulence generaon and dsspaon by rees by addng he erm (1) and (11) o he k and ε equaon respecvely. ηc 2 dau /2 (9) ε η 3 Cau d j k (1) 3 η Cau (11) Boundary condons d j : norh pavemen(average of Un1, 2 and 3) souh pavemen(average of Us1, 2 and 3) 11: Fgure 9 Ar emperaures on pavemen (July 28) Inflow condons o he smulaon area were generaed as shown n Fgure 1. Frsly, a 12m long sandard urban dsrc block s made based on he urban characersc whch represens he wndward urban area for he smulaon area. Then en such sandard blocks were cyclcally conneced o form a wnd log-low roughness zone Regon-S beforehand calculaon Regon-S Regon-S... Regon-S Regon-S nflow boundary use he vercal dsrbuon ha ouflow boundary dose no change any more as boundary condons boundary condons by preparaory calculaon nflow boundary 12: 13: Regon-U 14: objecve zone Regon-U 15: objecve zone Fgure 1 Mehod o oban nflow boundary condons 16: average ouflow boundary

5 large unform urban area. The assumpon of law of exponen n vercal dsrbuon of horzonal wnd velocy and urbulen energy was appled o he nflow of he model. We defne hs as S-condon. Afer checkng ha how much change occurred n vercal dsrbuons of horzonal velocy, ar emperaure and urbulen energy along he flow drecon, we found hese vercal dsrbuons became almos consan afer ar passed hrough egh blocks. Therefore we adoped hese dsrbuons as he nflow boundary condons for he smulaon model. Fgure 11 shows hese condons obaned. hegh[m] emperaure hegh[m] urbulen energy[m 2 /s 2 ] hegh[m] horzonal wnd velocy[m/s] The green hll s suaed 2 meers eas of he measuremen pon on Se C. Beween he measuremen pon and he green area here s a resdenal buldng zone. We defne hs as Case-1. As a comparson wo cases were smulaed. Namely Case-2 s 5% less green area han Case-1 and Case-3 s no green area. For hese cases he nflow condon-s was appled. The dsspaon rao n urbulence was calculaed usng Equaon (12). Ths s derved based on he assumpon ha generaed and dsspaed urbulences are balanced a he nflow boundary. The boundary condon of log-law was appled n calculang sress on surfaces. The op and sde of smulaon area was assumed havng a free-slp boundary. The hea ransfer coeffcen on surfaces was aken o be 11.6 W/m 2. The ar emperaure on he op of he analycal area was fxed a he emperaure measured by Kyoo Meeorologcal Deparmen. ( α 1).5 U s z ( z) = C k( z) α z z z z ε Calculaon of hea flux (12) In CFD smulaon sensble and laen hea flux was evaluaed by he followng equaons (Murakam, S.). T = ρcwt ' ' = K (13) p z µ C p K = (14) P r k = (15) 2 µ C ρ ε C l E = Lβα ( f f ) = LρD (16) w a s m z µ D = (17) m ρs c Smulaon resuls The smulaon was performed only for he me of 12: on July 28h and he resuls were nvesgaed. The surface emperaures measured on he buldng walls and grounds are shown n Table 1 and 2. The Fgure 11 Inflow boundary condons smulaon resuls of he ar emperaure of Se U are shown n Table 3. The average dfference beween measuremens and calculaon (measuremen values are subraced from smulaon values) s +.9ºC. The average dfference among he locaons where boh sunshne and shade appear (Us1 o Us 3) s +1.6ºC and hs s greaer han ha (+.3ºC) of he locaons where only sunshne appears (Un1 o Un 3). The smulaed ar emperaure a he hegh of 45m above he ground s 34.6ºC. Ths s exacly he same as he measured value. These resuls demonsrae ha he ar emperaure nfluenced by he hea exhaused from buldngs and he ground surfaces can be esmaed well by CFD. The smulaon resuls of hea flux of Se U are shown n Table 4. The smulaed sensble hea flux s 197W/m 2, however, he measured s 329 W/m 2. The Table 1 Wall and ground surface emperaure of Se U surface emperaure mesured pon norh wall 36.4 norh wall of U2 souh wall 42.6 souh wall of U1, U3, U5, U6 wes wall 37.6 wes wall of U4 eas wall 37.7 eas wall of U2 ground( alley ) 57.7 ground( souh pavemen ) 46.3 s ground( norh pavemen ) 61.4 n roof 6.5 p Table 2 Wall and ground surface emperaure of Se C surface emperaure mesured pon norh wall 36.8 norh wall of C souh wall 41.4 souh wall of C wes wall 42.6 wes wall of C eas wall.5 eas wall of C ground 52.2 average of Cn1 o 6 and Cg1 o 4 roof 45.2 average of Cn1 o 6 and Cg1 o 4 Table 3 Temperaures of Se U M - Measuremen; S - Smulaon. Un1 Un2 Un3 Us1 Us2 Us3 average Se U(M) Se U(S) dfference Table 4 ea flux of Se U a he hegh of 45m M - Measuremen; S - Smulaon. sensble hea flux urbulen energy k[m 2 /s 2 ] Se U (M) Se U (S)

6 smulaon resul s abou 4% less han he measured value. In Fgure 12 he dsrbuon of sensble hea flux a he hegh of 45 m s shown. We can see que much dfference exss and hs s due o complex urban buldng confguraons. In our calculaon he buldng beng under consrucon was modeled as a srucure formed by seel beams and columns, however, hs srucure may cause more effec on ar flow han smulaed. Ths problem wll be furher nvesgaed n fuure The smulaed ar emperaures of Case-1 (Se C), Case-2 (5% less green area), and Case-3 (no green area) are shown n Table 5. In Case-1, he dfference beween smulaed and measured emperaure of he locaons beng apar from he rees (Cn1 o Cn6) s +.5ºC, and ha of he locaons whch are close o he rees (Cg1 o Cg4) s -.8ºC. The average emperaure of he pons beng apar from rees (Cn1 o Cn6) of Case-2 s.2ºc hgher han ha of Case-1 and for Case-3 s.4ºc hgher han Case-1. These resuls show ha he ar emperaure of he pons beng apar from rees (Cn1 o Cn6) s lowered wh he ncrease of green area n he drecon of wndward. Ths agrees wh he measuremen resuls prevously shown. SIMULATION COMBININ RADIATION, CONDUCTION AND CFD The measured surface emperaures of buldngs and ground were used for CFD smulaon menoned n he former secon. Snce no surface emperaure s avalable for predcng envronmen of a gven urban area, we have developed a new smulaon code whch can smulae by combnng CFD calculaon wh surface radaon exchange calculaon and unseady sae hea ransfer calculaon of buldngs walls and grounds. Calculaon procedures are as follows (Fgure 13). 1) Inal emperaure: Calculang nal surface emperaures on he bass of unseady sae hea ransfer by gvng 3 days meeorologcal daa of ar emperaure, solar radaon and long-wave radaon. Ths mples ha ar emperaure dsrbuons n he urban space and radaon exchange are negleced n surface emperaure calculaon. 2) Condon seng a me j: Provdng meeorologcal daa a me j and evaluang he surface emperaures based on a me j-1 as nal condon. 3) Radaon exchange beween surfaces: Calculang hea absorbed a each surface elemen consderng muual reflecon of drec sunbeam and sky radaon, and long wave radaon beween all he surfaces. The shor wave absorpvy of a wnd pane s se.9, and.2 for wall and ground surfaces. The average absorpvy was calculaed by assumng he rao of me(j+1) Fgure 12 The dsrbuon of sensble hea flux a he hegh of 45 m Table 5 Temperaures of Se C M - Measuremen; S - Smulaon. average of Cn average of Cg amosphere(h=45m) Se C(M) Se C(S) dfference ( S-M ) green area 5% no green area radan energy surface emperaure buldng daa weaher daa calculaon of muual radaon exchange caluculaon of hea conducon of sold maeral calculaon of arflow, ar emperaure and humdy(cfd) emperaure wnd velocy urbulence energy 92 Fgure 13 Calculaon of hea conducon

7 he pane and wall surface area s.2 :.8. Long wave absorpvy s se.9. 4) Unseady sae hea ransfer: Calculang or updang he emperaures of wall and ground a me J+1 by solvng he 1-dmenssonal unseady sae hea conducon equaon. 5) Calculaon process: Proceedng seps from 2) o 4) a every one mnue and ar emperaure s updaed by performng CFD calculaon every 6 mnues. Smulaon case The dae and he place for he smulaon s from 1 o 16 o'clock on July 28h a Se U. Buldngs walls are composed of morar (12.5mm), normal concree (225mm), and morar (12.5mm). The room ar emperaure s condoned o be 26 C. The ground s composed of asphal (5mm), gravel (15mm), and sol (8mm). The boom sde of he ground was assumed o be hermally nsulaed. Dscusson of calculaon resuls Fgure 15 shows he surface emperaures of he walls and he ground. The average dfference beween smulaed and measured emperaure of eas walls s +.2 C and he average (smulaed - measured) dfference of all drecon walls s -.4 C. The maxmum dfference beween smulaed and measured emperaure of he ground surface s 1.7 C and he average dfference of all he measuremen pons s 2.1 C. Fgure 16 shows he smulaon resuls of urban ar emperaure. The dfference beween he smulaed and he measured ar emperaure s from -.8 C o +3.5 C and he average s.5 C. Snce he measuremen pon Us1 has lower measured emperaure han oher pons, large dfference rangng from +.7 C o +3.5 C exss. The dfference of oher measuremen pons s from +.8 C o +1. C and he average s +.3 C. As menoned above he smulaon resuls agree wh he measured values que well. Ths means ha hs smulaon can be used as a ool o analyze he nfluence of buldng shapes and urban confguraons on urban hea sland and o mprove he urban envronmen by predcng he effec of varous urban desgns or feasble modfcaons. CONCLUSIONS Inensve measuremen of urban envronmen was performed ncludng ar emperaure, surface emperaure of buldng walls and srees, solar radaon, long-wave radaon, sensble hea flux and laen hea flux, and he resuls were compared wh smulaon resuls. We can summarze he conclusons as follows. 1) The resuls of urban envronmen measuremen of a cenral cy whou much green and an unversy campus wh enough green show he exsence of dsnc ar emperaure dfference beween hese wo ses. The dfference can be well predced by CFD smulaon, however, measured hea flux a he hegh of 45m s 4% larger han he esmaed. One reason of hs dscrepancy may be due o oo much smplfcaon n modelng he buldng suaed n he measuremen se, bu hs mus be nvesgaed furher n our fuure work. 2) To predc he envronmen formed by an urban desgn or renovaon a new smulaon code QL,j QS,j T (oudoor) hea convecon Tso Tw1 Twn Ts hea conducon (1-dmensonal) Fgure 16 Smulaon resuls of ar emperaure of Se C (ndoor) T hea convecon Fgure 14 Calculaon mehod of unseady sae hea conducon Un1(S) Un1(M) eas wall(s) eas wall(m) wes wall(s) wes wall(m) souh wall(s) souh wall(m) norh wall(s) norh wall(m) Fgure 15 Smulaon resuls of wall and ground surface emperaure n, and s represens he locaons shown n Fgure 2.1 n(s) n(m) (S) (M) s(s) s(m)

8 combnng CFD smulaon, radaon exchange beween surfaces and unseady sae hea conducon of buldngs and he ground was developed. As good agreemen beween he measured and predced ar emperaures by hs code was obaned, hs smulaon code can be a ool for urban desgn and renovaon. In he presen nvesgaon hea generaed by human acvy or anhropogenc hea was no consdered. Alhough s no large n he presen cy because mos buldngs are low rse even n he cy cener and moble raffc s no heavy, we are plannng o nclude and analyze s effec n our fuure work. NOMENCLATURE a : Leaf area densy [m 2 /m 3 ](=.39m 2 /m 3 ) a w :Coeffcen of humdy conducon [kg/m 2 skpa] b : Evaporave effcency [-] C : umdy rao [kg/kg(da)] C d : Ressance coeffcen of he crowns of rees [-](=.5) C p : Specfc hea of ar [J/kgK] C : Model consan [-](=.9) D m : Coeffcen of urbulence dffuson[m 2 /s] E s : Seam amoun from leaves ranspraon [kg/m 2 s] f a : Paral pressure of seam [kpa] f s : Sauraon paral pressure of seam [kpa] g : Acceleraon [m/s 2 ] : The ground surface hea flux k : Turbulen energy [m 2 /s 2 ] K : Coeffcen of hea conducon [J/msK] 6 L : Laen hea of vaporzaon (= [J/kg]) P : Ar pressure [N/m 2 ] P r : Prandl number of urbulence[-](=.9). q : ea generaon [J/m 3 s] S c : Schmd number of urbulence[-] (=.9) : Tme [sec] T : Ar emperaure [K] T : Basc ar emperaure [K](=33) u : Velocy [m/s] U s : Wnd velocy on reference hegh [m/s] V n : Volume of he crown of rees [m 3 ] x : Space co-ordnae [m] α : Exponenal order[-](=.2) β : Coeffcen of volume expanson [l/k] ε : Dsspaon rae of urbulence energy [m 2 /s 3 ] η : The rao of he crowns of rees [-] µ : Coeffcen of vscosy [kg/ms] µ : Coeffcen of eddy vscosy[kg/ms] ρ : Densy of ar [kg/m 3 ](=1.176) Murakam, S. e al.,: Compuaonal Envronmen Desgn for Indoor and Oudoor Clmaes, Unversy of Tokyo Press, 2 Tukamoo, O. e al.,: Meeorologcal sudy noe No.199, 21, Meeorologcal Socey of Japan Tanmoo, J. and T. Kaayama: A sudy on urbulen flux n an urban and rural area based on a feld measuremen, J. Arch. Plann. Envron. Eng., AIJ, No. 513, 69-76, November 1998 Wllamson, T. J. and Evyaar Erell: Thermal performance smulaon and he urban mcroclmae: measuremen and predcon, Sevenh Inernal IBPSA Conference, Ro de Janero, Brazl, Augus 13-15, 21 Yoshda, S.: Sudy on effec of greenng on oudoor hermal envronmen usng hree dmensonal plan canopy model, J. Arch. Plann. Envron. Eng., AIJ, No. 536, 87-94, Oc., 2 REFERENCES arayama, K. and S. Yosda: Numercal sudy based on unseady radaon and conducon analyss, Predcon of oudoor envronmen wh unseady coupled smulaon of convecon, radaon and conducon -Par 1-, J. Arch. Plann. Envron. Eng., AIJ, No. 556, 99-16, June