trng dung mo hinh MIKE 21FM danh gia tic citing dm nook xa tir nha may nhiet dien Thang Long den khu vkrc lay nuac

Transcription

1 Tap chi Khoa hoc DHQGHN: Cac Khoa hoc Trai dat va Mei tnemg, Tap 32, SO 3S (2016) trng dung mo hinh MIKE 21FM danh gia tic citing dm nook xa tir nha may nhiet dien Thang Long den khu vkrc lay nuac D4ng Dinh Doc 1,*, TrAn NgQc Anh''2, TrAn Ng9c Vinhl 1 Trung tam DOng luc hoc Thfzy khi Mai trtrbng, Tnrenzg Dgi h9c Khoa hoc Ty. nhien, DHQGHN 2 Khoa Khi tuvng Thety van & Hai throng h9c, Tnthng flai h9c Khoa hoc Tu nhien, DHQGHN Nhan ngay 08 thing 8 nam 2016 Chinh sira ngay 26 thang 8 nam 2016; Chip nh4n clang ngay 16 thang 12 nam 2016 Tom tat: Hien nay co rat nhieu cac nha may nhiet dien da va dang ductc xay dung ten ca nuac, dic biet la a cac tinh co sin nguon tai nguyen than di nhu Quang Ninh, Thai Binh hay Ninh Thuan. Viec nghien cuu dinh gia lan truyen nhiet cho cac nha may la thuc su can thiet do nhiet do cua nuac lam mat se gay anh huang trot tiep den Ming suit cua nha may. Bai bao nay thuc hien nghien ciru dinh gia lan truyen nhiet do tic dong cua nuac xi dm nha may nhiet dien Thang Long. Trong thiet ke cua nha may [1, 2], doing 'Ong xa nuac nong cua nha mayduqc clit 6 thug/rig luu song Man, trong khi do cira but nuac lam mat lai Tat ha luu song Man khu vuc Vinh Cita Loc. Vi vay, nh6m nghien tiro Ta. thuc hien tinh toan va danh gia tae dong do lan,truyen nhiet bang phucmg phap mo hinkhoa. Nhom tic gia da sir dung b0 tong cu MIKE 21FM ket hcrp vii thou dia khao sat do dac cac yeu to dia hinh, thily hai van tai khu Arc nghien ciru. Vbi bien do nhiet chenh loch gala nuac but va nuac xa nho han 8 C duqc coi la bat lcri doi vii hieu suit cua nha may, ket qua tinh toan cho thay clang nuac nong xi a thucmg hru song Man da gay anh huang truc tiep tai nhiet do nuac tai vi tri cira hut, dac biet vao miia he khi trieu rut. SO luang gia nuac tai vi tri cira hot vucrt nguirng trong thing cao nhat la 153 gia vao thing VII. Tic khoa: Mike 21FM, lan truyen nhiet, nhiet dien. 1. Gioi thqu chung 1.1. flat van de Lan truyen nhiet trong mei trikmg nuerc la met bai toan co. ban va quan tr9ng doi vii thiet ke xay dung cac ding trinh xa thai nuac nong ra mei tnrong,noi chung, nha may nhiet dien not rieng. Nguon nuac nong nay se khien nhiet de nuac khu vuc xa tang len keo theo cac su thay doi ve moi trirong &Ong thai tic &Ong trer *Tac gia lien he. DT.: dangduc@hus.edu.vn 56 lai chinh vi'ec van hanh cua nha may nl vi tri dm lay nuerc nam trong khu,vuc anh huang. Van de danh gia tic deng ye moi tru?mg tiz nuac xa nay da ducfc de,c4p troll* nhieu nghien tiro va la met yeu cau bat buec de xay dimg cac cong trinh nay. Trong bai bao nay se di sau trinh bay khia canh tic deng tai chinh ban than su van hanh cua nha may. Vi du tai Nha, may nhiet dien Thang Long la met dien hinh de lam bai toan mau cho cac nha may nhiet dien khac. Theo thiet ke, nha may nhiet dil Thang Long (xa Le Lgi, huyen Hoanh Be, Quang có vi tri cua xa nuac nong tai thugng luu cau Da Trang Oren song Man) va cua hint mac a phia

2 D.D. flue va nnk. / Tap chi Khoa hoc DHQGH7V: Cac Khoa hqc Trai c#at va MOi &won, Tdp 32, SO' 3S (2016) ha luu so vii cua xi (gin khu vuc lung chinh) [1, 2]. Khoang each gift cua xa va cfra hint chi khoang 2, 6 km (theo, duemg song), khoang each khong qua xa, ket harp vori dieu kien thily trieu khu vuc co bien do lan. Do vay nguy ca khu vuc dm hitt se chit,' tic dong bed dong nuac nong xa ra cita nha may khi trieu rat. Hi@i tucmg tich nhiet tai khu vuc hint la mot van de lien quan nut tiep tai ding tic van hanh nha may, anh huang lan tai hi8u suit lam 1.2. Khu vuc nghien citu Dv an Nha may Nhi't dien Thang Long 600MW xay dung tai xa Le Lgi, nam phia Dong bac huy0 Hoanh BA, tinh Quang Ninh (Hinh 1) da dugc Thu tuang Chinh phu cho phep dau to theo van ban so 26/TTg-CN ngay 05 thing 01 nam Theo thik ke [1-3], nha may nhilet dien Thang Long co 2 to may, moi to may c6 ding suit 300MW, khi hoat dong nha may se can cung cap mot Luang nuac lam mat binh ngtmg cling nhu xa ra moi twang nuac nong sau lam mat khoang m3/h (tucmg ducmg 27.6m3/s, hoat dong &Ong thi hai 2 to may). Nhi'0 do nuac lam mat tai dm hut theo thiet ke khoang C, nguon cap nuac lay to khu vuc phia &Ong bang tai xi mang, gin nga 3 song Man vinh Cfra Luc. Nguon xa nuac ruing sau khi lam mat binh ngung se ducyc, thai ra song Man, nh* do nuac xa theo thiet ke khoang 34 C. Nguon nuac nong xa ra moi twang se gay nen sv gia tang nhi't do cue bo tai vi tri cua xa, lugng nhiot nay se lan truyen ra xung quanh va co nguy co anh huoug tai vi to cua hut nuac lam mat dm nha may. Hi@t suit van hanh cua nha may phu thuoc rat lan vao sv duy tri dugc nh* do chenh l&h AT ttfi da gifra nuac cap va nuac xa (AT > 8 C). Trong nghien cfru nay, khi nh* do nuac tai vi tri cfra hut Ian hon 32 C thi se gay ra bat lgi cho sv van hanh cua nha may. Do vay can phai c6 nghien cuu danh gia the dong cua nuac xa tai nguon cap trong dien 164n hi0 trang theo thiet ke va de xuat cac giai phap nham on dinh nguon nuac mat tai cfra hut. Vi tri Nha may Nh* din nam,canh luu vuc song Man ye phia Bac cau Da Trang thuoc duang vanh Dai phia Bac not vii TP. Mang Khu vuc nghien cfru thuoc \ding ha luu cac con song Trai va song Man. Khu vuc thugng luu cac song nay dugc ngan beri cac dap nuac ngan man va cap nuac sinh hog, nong nghi0 cho khu vuc thugng luu, cu the: tren song Trai c6 dap Wing Ho co nhiem vu cung cap nuac sach cho ngueni dan Thi tan Trai va cac \rang phi,' can, tren song Man thi dap Da Trang co nhilem vv ngan man dong thi cung cap nuac sach cho ngtrai dan khu vuc xa Thong NhA0[4]. Hirsh 1. So do khu vuc nghien ciru tinh town danh gia lan truytn ith* nha may nhi* dien Thang Long.

3 58 D.D. Dar va nnk. /Tap chi Khoa hqc DHQGH1s1: Cac Khoa hoc Trai ctdt viz Mai Intern, Tap 32, Sá 3S (2016) Phtrong phi!) nghien ctiu tinh town lan truyen nhiet bang ding cu mo hinh town MIKE 21FM 2.1. Khai quat ve cong cu mo hinh MIKE 21FM Tr& the giai da có nhieu cac mo hinh se de tinh toan, mo phong qua trinh lan truyen nhi8t trong m6i tnrong mac khu vuc gan ba, khu bai tam, khu nuoi tong thily san va di)/ thuoc vao doi tuong, mijc dich nghien ciru, vi8c ap digig cac loai m6 hinh tinh toan cong khac nhau. MOt so mo hinh pho bien c6 the k8 den: MIKE cila ViCen They luc Dan Mach (DHI), m6 hinh POM, SMS cila Hoa Ky, Delft3D cua Dai hgc cong ngh8 Delft, Ha Lan... CS Viet Nam, trong nhfing nam gall day, hiking nghien ciru, xay dung va sir dung mo hinh trong nghien cuu thily dong luc mei truemg dang rat dugc quan tam. Trong do nhing nghien ciru, dien tra, tinh toan o nhi8m mei tnrang Wing vinh va khu vuc yen bien - khu vuc tap trung cho yen cac hoat dong kinh to alas con, ngtrai da, dang dugc lien hanh. CO rat nhieude tai tinh toan qua trinh phat tan va lan truyen nhi8t trong yang song, cira song yen bien hay ngoai khai có 51 nghia lan ph ic vu khoa hgc va dan sinh nhu "Tinh toan truyen nhiet teen he th6ng song Tra Ly tinh Thai Binh khi trung tam di8n luc Thai Binh lay nuac lam mat", (king m6 hinh MIKE 3 tinh toan lan tiny& nhi8t cho nha may nhi8t di8n Quang Trach", "Mo phong qua trinh lan truyen nhiet cua nuoc lam mat nha may nhit dien 0 Mon"... Phucmg trinh ca ban trong MIKE 21/3 la phuang trinh 2/3 chieu ap dung cho chat long khong nen dugc, trung binh Reynolds tea phucmg trinh Navier-Stokes tang \Teri cac gia thi8t Boussinesq va ap ltrc thily tinh. Mien tinh toan dugc rofi rac hoa sir dung phucmg phap th8 tich hue han (Finite volume method). Theo chieu mat phang cac phan ter cif) the chia thanh phan tam giac hoc phan ter tir giac hoc kat hap ca hai lai phan ter Ouch phi cau trocunstructured mesh). Theo chieu dimg cac phan tit dugc chia co cau tine dua then cao trinh, dia hinh hoac ket hgp ca hai. [5, 6] Tr& ca sa da dugc nhieu de tai khoa hqc sir dung va hem chimg v8 tinh khoa hoc va do tin cay ves k8t qua dm mo hinh [7-13], nghien can da lea chgn mo hinh MIKE FM Couple trong be mo hinh MIKE dm Vin Thily hrc Dan Mach (DHI) de tien hanh nghien ciru, tinh toan lan truyen nhi8t cho khu vuc nha may Nhiest dien Thang Long Xiiy dung m6 hinh tinh toan lan truydn nhiet khu vuc nha may nhiet dien Thang Long Cac buck thief lap, xay dnng mo hinh tinh toan they dong luc va lan truyen nhi8t cho khu vuc xa thai tea nha may Nhi"8t di8n Thang Long dugc ini8u to trong Hinh 2. Met dot khao sat do Trung tarndong luc hgc They khi Mei trtrang da dugc to chirc nham khao sat do dac bo sung cac so li8u v8 dia hinh duai mac va cac you to thily dong luc hoc tai khu Arc nghien ciru trong thai gian tir 08/07/2015 den 13/07/2015. So liou dau 140 (Thuthip xt HO qua da 1 khan sat tong gum va I., UM sat no sung) Xay dung mien tinh toin Thiet kip him tinh roan IshOog dat Gia thiot bo thong so ma blab Thiet Itip bien tinh Man MA phang CliC kith ban Diinh gia kot qua tinh loan Hinh 2. Khung thgc hien tinh toan danh gia lan truy'n nhit cho khu vuc xa va cap ntrac cua nha may nhit dien

4 D.D. Dix va nnk. /Tap chi Khoa hpc DHQGHN: Ctic Khoa hqc Trtii cat va Moi triton, Ttip 32, SO' 3S (2016) BAN DO DIA HINH KHU VI,fC NGHIEN CVU maw"...a IMO X THONG HAT ,L01111 Chi, gal * Nhd mft Xi Pang VI Ill CU hirt.xa uerm X3g ahuyen Kthil tri nha n16y law vvc Go dia hinh Hinh 3. Ban do cao se.) khu v,rc nghien ciru Si; lieu phyc vu tinh toan - Da lieu dja hinh: Binh d6,dia hinh khu vgc nghien ciru dugc thu thap Dim co dia hinh day bien tsr le 1: [9] va ktt hgp vai so lieu dia hinh dugc do dac thgc, to qua dect Ichao sat bo sung. MOt mo hinh so do cao vai do phan giai 10x10m da dugc xay chmg cho khu vi,rc tinh toan (Hinh 3). - Du lieu khi twang tin:1y van: So lieu thing chay: Deng chay ten cac song do vao Vinh Cira Luc: teen cac song Man, song Trai, Dien Vgng luu lugng trong thori Ick do dac khong lorn. Dac biet, ten cac song, Man va song Tr6i deu co ding trinh dap ngangan sat vai khu vkrc nghien cfru., Cac dap ngan nay c6 tac dung ngan man va cap nuac (nuac sinh hoat, nong ngh4) cho cac khu vgc dan cu xung quanh, do d6 neu khong mua, luu lucmg tren cac song nay do vao Vinh Cfra Luc rat nho, c6 the coi bang khong. Trong thoi gian khao sat da xuat hien nhimg can mua vita va nhe (ngay 10/07), tuy nhien lugng nuac tir cac song do ve Vinh la khong clang ke (qua quan sat lugng nuac tran qua mat dap). Do ten \rung tinh toan khong c6 tram thfiy van nao do luu lugng dung chay tai 3 song Man, song Trai va song Dien Vgng nen nh6m nghien ciru thkrc hien khoi phuc dung chay tren 3 con song d6 den bien tinh toan cua mo hinh teen cac con song. Vic khoi phuc dugc thkrc hie'n bang mo hinh mua -clang chay, et-mg la mot mo dun dugc tich hgp trong bo mo hinh MIKE cna DHI la Mike NAM. BO thong so mo hinh da dugc ke thira tir thong so dugc tinh toan cho luu Arc song Cau [6], day la luu vuc lan can va co dieu kin dia 1ST to nhien tucrng to yeti khu vkrc nghien cfru, vi vay phuang phap tuang to dugc sfr dung de tinh toan khoi phuc thing chay, cung cap bien dau vao cho mo hinh. Nh* iih* do khong khi trong thoi gian do dac dao dong trong khoang tir 27 C den 35 C (hinh 4). Nhiest do mr6c do dac tai vi tri cau Bai Chay dao dong tir 28 C den 30 C (Hinh 4). Su Phan tang nhiest do theo do sau IA khong Bang Ice, cu the: tai vi tri Cau Da Trang (vai do sau 3m), chenh lesch nhi'et do lan nhat tang mat va tang day trong then ky quan trac khoang 1 C; tai vi tri cang gan cfra hut (do sau 4m) co nh* do chenh kch gift tang da.?, va tang mat khoang 1 C, tuang to voi vi tri tai cau Bai Chay.

5 60 D.D. Dtic va nnk. / Tap chi Khoa hoc DHQGHN: Cac Khoa hoc Tali dat va Mai triton Tap 32, So 3S (2016) Tow Torn Ws Trtuae-Oar ~do ielanomi peg q Hinh 4. Nhi't do khong khi va nh*do nuac 3 tang tai cau Bai Chay. St) lieu hai van: Muc nuac tri6u thap nhat tai vi tri cau Bai Chay la H=-0,92m, cao nhat la H=+1,3m, do lan thily trieu dao dong khoing lm tir ngay 8 den ngay 11, to cuoi ngay 11 den ngay 13 co do lon khoang 1,5-2m. (Hinh 5). Do vi tri an Da Trang va cau Bai Chay gin nhau, dia hinh khong qua chenh loch nen che do nitre nuac tai 2 vi tri la twang dong vii nhau (hinh 5). DO man tai vi tri cau Rai Chay dao dong trong khoang 26-29%o, chenh loch do man giira cac tang dm nuac khong ding k6, nho hail 2%0 (Hinh 6). Tai vi tri cau Da Trang, do man dao dong trong khoang 18-23%0, chenh loch do man giira cac tang cila nuac nho khoang 2%o (Hinh 7) cau BaiONey Hinh 7. DO man 3 tang cita nuac tai eau Da Trang. ThoM kst kiem chirng mo hinh So Wu dung de hem chung mo hinh gom: so HO mtrc nuac, nh* do, do man tai 2 vi tri cau Da Trang va cau Bai Chay du9c do dac qua dot khao sat thang 7/ Thiet lap mó hinh lan truyen nhiet Pham vi mien tinh T6ng d*1 tinh mien tinh toan la 891=2. Giai han phia tren cac song: song Man la dap ngan man (khoang cach tai cira hut khoang 11 km); song Trai la dap Dong Ho (khoang each den dm hut khoang 6 km), song DiZn Vong la tir cau Dien Vong (khoang each den vi tri cua hut khoang 13 km). Gieri, phia bien: phia &rig la dueng vao dao Tuan Chau va Dao Tuan Chau, phia Nam la cac bien long ngoai bien, cach tram Hong Gai 3.3 km.mot so cac ding trinh cang nha may xi mang Thang Long, Ice dm bang tai nha may xi mang Thang Long, ke dm bang tai nha may xi mang Ha Long da dugc dua vao luai tinh town ooma Hinh 5. S6 lieu muc nuac thtrc do tai cau Bai City va cau Da Trang. Hinh 6. DO man 3 tang cila nuac tai chin cau Bait. Chay. Hinh 8. Lu6i tinh 2D trong MIKE 21FM.

6 D.D. flirt vet nnk. / Tap chi Khoa hoc DHQGHN: Cric Khoa hoc Trai djt va Mot trztenzg, Tap 32, So 3S (2016) Thiet kip lit& tinh toan MIKE 21FM Luai tinh toan phi eau trac dua tren cac phan ter tam giac tuyen tinh, lubi tinh dugc,chia thanh 4644 o luai tam giac c6 dien tich phan to nho nhat 1.000m2, lchoing each gifra hai nut tinh nho nhat khoang 30m. Khu vuc ngoai bien, c6 dien tich phan ter nho nh't m2 (khoang each gifia cac nut tinh trung binh ter / m)(Hinh 8). Dieu kien bien & dieu kien ban dju Dieu kien bien Bien muc, nuac (cac bien phia bien): Sir dung they trieu tai tram Hong Gai nam 2015 (doi von tnrong hap hien trang) va they trieu du tinh vai b0 hang so,dieu dugc phan tich ter they trieu tram Hong Gai. Bien dong chay: dong chay trong song dugc lchoi phut bang mo hinh they van MIKE NAM, Om 3 bien tai dap acing Ho, dap song Man va cau Dien Yong. Bien nhiet do va do man: Su dung so lieu trung binh dugc cung cap ter cac mo hinh du bao toan cau. Cac so lieu tinh toan cac kith ban se dugc thong ke to so lieu nhieu nam tai tram Bai Chay. Cac dieu kien khi tugng khac: nhiet do khong khi, do,am, luang mua, boc hai trung binh thang nhieu nam tai tram Bai Chay dugc sir dung trong cac ket qua tinh toan. Dan vi to van da thiet lap mo hinh ngoai su trao doi nhiet trong nuorc, c6 xem xet tai su trao doi nhiet von m8i twang khong khi. Dieu kien ban ciciu Dieu kien ban du dugc thiet lap la muc nuac trung binh, van toe (long chay va nhiet do tai cac bien tinh toan tea mo hinh Kiem cluing mo hinh tinh toan lan truyen nhiet Viec hi'eu chinh mo hinh dugc thuc hien so sanh ket qua tinh toan von ket qua thuc do cac yeu to they luc (mix nuac), nhiet de va dikman cua nuac tai 2 dia diem la eau Da Trang gan vi tri cua xa nuac so vai thiet ke va cau Bai Chay trong khoang thin gian do dac khao sat ter 08/07/2015 den 13/07/ tueDo (m"31strni 0-TinkTeen ionntsj Lou iuong hnh toan 8 thuc do Um Bo, Chay 3000 H-ThucOo Pm) "*. N Tinterain IS OA WOO ono , we num** loin & hue do imi 13sithsy WOO A Hinh 9. K6t qua hien chinh luu *mg tinh toan tai tram Bai Chay. Hinh 10. K6t qua hien chinh mkrc nub tinh toan tai tram Bai Chay o. 4, C77-13 WOO CO/30 07-ta Hinh 11. K6t qua hien chinh 'we mak tinh town tai cau Da TrAng. CS.ThucDo [ronts;rn].. 0-TiohToan irn"3/0] Luu luong hnh toan & thuc do tat Bar Chay I 2000 Muc nuoc Mal loan a thuc do tar cau Da 7 rang Hinh 12. K6't qua Wu chinh luu lugng tinh toan tai tram Bali Chay.

7 62 D.D. Dirc va nnk. / Top chi Khoa hoc DHQGITIV: Cac Khoa hoc Trai ctat va Moi trvemg, reip 32, So 3S (2016) Napaeftemcimulwo -.1,1*011 kidolliblu Ft) - lan tai 2 diem. Do d6 co the sir dung be, thong so mo hinh nay de ap dung cho tinh toan lan tntyen nhiet tir dung nuac xa cita nha may Nhiet dien Thing Long den cira hut cita nha may. Hinh 13. Ke't qua hiou chinh nhiot do nuac tinh toan tai au Di Tring. N SO ,04K, Hinh 14. KOt qua hiou chinh nhiot do tinh toan do tai tram Bai Chay. Wadi Ilowdo On 0.4 DONA tlebtdo BO [LOIN Hinh 15. K6t hiou chinh do man tinh toan tai tram Bai Chay ftebelt01 TO.groll Nam.. dm Di I' *a - Hinh 16. K6t qua hwu chinh do man tinh toan tai cau DA Trang. Ket qua hieu chinh cho thay (Hinh 9-16): Duemg qua trinh mvc nuac tinh toan bang mo hinh kha tucmg dung va chink xic vii duemg qua trinh thvc do tai 2 diem cau DA Trang va cau Bai Chay. Duang qua trinh nhiet do tinh toan kha sat vii duang thvc do vii bien di) chenk lec nhiet dq gicra 2 duang khong qua 1 C Or diem cau Bai Chay va 'thong qua C or diem cau Da Trang. Tucmg tv vii do man, ket qua tinh toan chenh Lech vii thkrc do khong qua 3. Clic kich ban tinh town danh gia lan truyen nhi?t nha may nhi?t din Thing Long 3.1. Xcly dung kich ban tinh toan Tren co so phan tich cac dac diem khi Wong thity van, dia hinh, nguon lay nuac lam mat va vi tri dat cira hut, cira xa nha may. Cac kich ban duai day dugc, tinh toan nham danh gia lan truyen nhiet, khuech tan nhiet den vi tri cira hut nuac lam mat theo cac lieu chi: Tinh toan vii he so khuech tan gay bat lai nhat tai nhiet do tai cira hat theo yeu cau thiet ke. - Tinh toan cho 4 mica trong nam (theo cac pha thity trieu Ichac nhau: trieu cao, trieu trung binh, trieu thap) va chi tiet cho timg thang trong 1 nam,dien hinh (day khong phai la nam cvc loan ye cac gia tri, cac dieu kien bien au dugc lay trung binh thang nhieu nam, do vay trong dieu kien thuc to neu cac yeu to dau vao nhu: nhiet do moi tracing, nhiet do nuac... kin bat thuang thi cac ket qua se theo chieu huomg bat 1cri va ngtrcfc lai.) - Cac gia tri ve vi tri va cac thong s6 v'e lugng xa, lucmg hut dm nha may theo thong so thiet ke khi van hanh 2 to may: 99400m3/s (tuang ducmg 27.6m3/s). Tir cac tieu chi tren, cac kich ban dugc hra chun tinh toan nhu sau: - KBA: Kich ban dia hinh hien va ding suit hut/xa van hanh theo thiet ke nha may yeti cac he,so khuech tan khac nhau de hra chon he so khuech tan gay bat lcri nhat tai nhiet di) tai cira hut rank lam mat vii so lieu that do khao sat thang 7/ KBB: Kich ban dia hinh hien, trang va cling suit hut/xa van hanh theo thiet ke nha may yeti trieu cao, trieu trung binh, trieu thcip va thai gian 4 mita trong nam (xuan, ha, thu &Ong) Mo phong lan truyen nhiet cac kich ban tinh toan.

8 D.D. Dtic vii nnk. / Tap chi Khoa hpc Ctic Khoa hpc Trai ctat va Moi truying, Tip 32, Sd 3S (2016) KBC: Kich ban dia hinh hi'en tang va ding suat hilt/xi van hanh theo thiet ke't nha may yeti nam dien hinh (gom cac pha trieu cao, thap, trung binh). Kich ban C tinh toan viii nam co,thily trieu dien hinh. Trong chu6i chu ksr,nhieu khoang 18,61 nam co 1 nam co trieu dien hinh. Trong chuoi so lieu mirc nuac tai Hong Gai to nam 1980 den 2015 thi nam 2005 có narc nuac trieu dien hinh Ke't quit vet thcio ludn Kich ban A tinh toan viii so lieu dia hinh hilen trang va thiet ke cua nha may viii so lieu do dac thing 7 nam 2015 (Hinh 17). Chay kich ban viii cac he s6 khac nhau (he so khuech tan dao dong tir den 10), ket qua tinh toan cho thay: yeti he so khuech tan D=0,001 cho twang nhi'et do bat loi nhat tai cua hut va D=10 cho truirng nhiẹt do it bat loi nhat. Tuy nhien, du,trong trtremg hop bat lcri nhat hay it bat lqi nhat thi nhi'et do tai cira hut van bi anh hung beri dong nuac tir cua xa cua nha may nhi'et dien Thang Long, tai day xay ra tinh trang tich luy nhie t, nhi'et,do tang cao khi trieu rat, dat Binh tai chan trieu va giam dan khi pha trieu len. Trong throng hop bat lgi nhat (Hinh 18,19), nhiet do tinh toan cao nhat tai cira hut la 35.1 C, thoi gian duy tri nhi'et do tai cua hut cvc doan (bien do <8 C) khoang 10-,12h/ngay dem. Trong twang hop it bat lgi nhat (D=10), nhi'et do tinh toan cao nhat tai cua hut la 32.9 C, thgi gian duy tri nhi'et do tai cua hut eye doan (bien di) <8 C) khoang 4-711/ngay dem (Hinh 20, 21). Hinh 18. Truing nhiet do lem nhat tai vi tri cira hit veri D = 0,001. Hinh 19. Bi6'n trinh nhiet di) tai dm hitt (trdmg hop bat 10)..-4 Hinh 20. Tru&ng nhit do5 lem nhat tai vi tri cua hat yeti D = Hinh 17. K6t qua tinh toan nhiet dq tai cira hut viii 2 phucrng an KBA. Hinh 21. Bi6n trinh nhiet do Lai cua but (trdrng hop it bat

9 64 D.D. nnk. / Tap chi Khoa hoc DHQGHN: Ccic Khoa hoc Trai va Moi Throng, Ta'p 32, S'd 3S (2016) mii-trievcao CI cwt.,000.11/ms Meg COMM& XY.00, mItt PIPX X -X11-inek Cao [dog Ci - : : : 2r. 22 Hinh 22. Bien trinh nhiet c10 tai vi tri cira hilt 4 mila vai phucmg an trieu cao. Hinh 23. Bien trinh nhiet de! tai vi tri cfra hut 4 mila vai phucmg an trieu trung binh. revetdo- them 1-01-Tr.illt. I.. CI Cu Nui eil*cx.thang 1V-V,-Tne.11.1 lekop C) W11-4X-Trtx..11., (clip CI W.e100,Thang [4.4/ C) Cummul Lk.aucc - Cuarkst NhaeNtxX-Tn.r., % s6 gia bat lcri ca nam). Thai gian xay ra tink trang tich lfiy nhiet rcri vao pha trieu reit, luang nu& ming tich tren song Man bi thing thily trieu rut ra, tic dong true tiep tai dm hut. Trong pha trieu len, dong thily trieu thang the, day lucmg nuac nong tren song Man ye phia thuang luu, tong thai giin nay nhiet do tai hat dam bao,thiet ke. Ket qua nhu vay anh huang rat lan den viec van hanh chay cac to may va phat dien nha may. Kich ban C tinh tor tnrang nhiet cho 1 nam dien hinh, ket qua tinh tor cho thay, nhiet de tai hut duy tri bat khoang 840h/nam (trung binh 2.3h/ngay). Trow d6 thing VII co thori gian duy tri keo dai nhat 153h (trung binh 4.9hingay). ket qua cac kich ban, danh gia duac anh huang,cua nhiet do clang nuac xa den vi tri cung cap nuac lam mat theo timg thai diem hay theo terns maa trong nam, va tong the inh huang den nha may nhu nhiet de vi pham, thin gian vi pham, tong thai gian vi pham va thoi diem vi pham. Vi vay can dua ra cac giai phap de cai thi'en nhiet de tai hut nuac dam bao quy trinh van hanh nha may dat c8ng suat toi da 4. Ket Hinh 24. Bien trinh nhiet de) tai vi tri yen phuang an trieu thap hut 4 miia Kids ban B tinh tor \Teri cac trirang hop trieu cao, trieu trung binh va trieu thap. Vao inua he, ket hap dieu kien trieu cao, thai gian duy tri nhiet dos bat trong 15 ngay c6 the dat 98h (Prang ducmg 27% thori gir var,i hanh), v6i cac thai ks, trieu trung binh, trieu thap thoi gian bi anh huang tuang chiem 26% va19% thai gian van hanh (Hinh 22-24). Kich ban C tinh toan truang nhiet cho 1 nam dien hinh, ket qua tinh toan cho thay, nhiet de tai dm. hat duy tri bat lcti khoang 840h/nam (trung binh 2.3h/ngay). Tror,ig da thang VII c6 thai gian duy tri keo dai nhat 153h (trung binh 4.9h/ngay) (hinh 27-28). Tiing the:6 gian bat dm 4 thang (V-VIII) khoang tren 640h (chiem Nghien cfru da sfr dung be mo hinh MIKE 21FM de thiet lap va tinh toan lan tniyen nhiet cho khu vuc xa va cap nuac lam mit nha may nhiet dien Thang Long.,Ket qua tinh toan tir mo hinh cho thay tong, dieu kien hien trang, tai vi tri cira hut chac chan xay ra su tich lily nhiet, bien do nhiet giam thap that chi con khoang 3 C gay anh huang nghiem trong toi ding tac van hanh nha may. Tong s8 thin gian bat trong nam (At<8 C) khoang, 840h, trong do thang VII, la thing bat that vai 153h. T6ng thai gian bat lai dm 4,thang lchoang tren 640h (chiem 64% s8 gior bat lgi nam). Thai gian xay ra tinh trang tich nhiet hut rai vao pha trieu rut, lugng nuac ming tich tu tren song Man bi dong thily trieu rat ra, tac dong true tiep tai dm. hut. Trong pha trieu dong thily trieu thang the, day

10 D.D. Dtic va nnk. / Tgp chi Khoa hoc DHQGHN: Ccic Khoa hoc Trai clat va Mai truc'mg, Tap 32, So 3S (2016) luong nuac ming ten song Min ve phia thuang luu, trong then,gian nay nhiet do hilt dam bao thiet ke. Nhu vlay có the thay, viec bo tri vi tri cfra, xa va hilt la rat quan tong, anh huang lan den su van hanh cua nha may. Day la mot hru y lchuyen, cao cho cac du an nhiet dien trong thefi gian sap tali. LM cam an Nghien can nay duorc thuc hien tai Trung tam DOng hp hoc Thily khi Moi twang, Tngyng Dai hoc Khoa hoc Tv nhien, DHQGHN vi su tai trq ye kinh phi va cac thiet bi khao sat. Nhom thuc hien xin tan tong cam an su ho tq qust bau nay. Tai lieu tham khao [1] Thang Long 2x300 MW thermal power plant project, 6/2014, Thang Long 2x300 MW thermal power plant project (Jetty part), Design description. [2] Thang Long 2x300 MW thermal power plant project, 6/2015, Description of water supply and drainage part. [3] Ging ty c6 phan nhiet dien Thing Long, 5/2008, Bao cao dinh gii tic dong mei truentg b6 sung, du an nha may nhiet dien Thang Long 2 x 300MW. [4] Trung tam Deng lvc hoc Thity khi M6i tnrerng, 2015, Bio cao tong ket nhiem vu "Dinh gia tic dong cila nuerc xi lam mat nha may nhiet dien Thing Long den khu vvc cap nuerc va de xuat giai phap". DHI Water & Environment, Mike 21 Flow Model, Hydrodynamic ModuleScientific Documentation. DHI Water & Environment, Mike 21 Flow Model, Mud Transport ModuleScientific Documentation. Vien Tai nguyen & Moi truing bien, 2006, Xay dung me hinh Ian truyen chat o nhiem cho Vinh Ha Long Vinh Bai Tir Long, bio cao tong ket Dv an. [8] Hoing Thi Hang Nga, 2013, Sir dung mo hinh Mike 21 &nit gia qui trinh lan truyen nhiet \rung cira song tra 1Sr dueri anh hue:mg cita nha may nhiet dien Thai binh 2, LuAn van Thac si, DH KHTN. [9] Le Hoang Anh, 2013, Dinh gia anh huang tir thing thai nu& lam mat cita nhi may dien hat nhan Ninh ThuAn 2 den mei tnthng nuerc va sinh thai khu vvc xung quanh, luan van Thac si, DH Thity lqi. [10] Vien khoa hoc Khi tic:mg - Thity van vi Mei twang, 2007, Mo phi:mg qua trinh Ian truyen nhiet cita mrerc lam mat nha may nhiet dien O Mon. [11] Ngo Thi Nhip, 2011, Ong dung mo hinh toin nghien cunt Ian truyen nhiet nuerc thai ctia nha may nhiet dien Phi Lai, Luan van thac si Mei tnthng, Tnrimg Dai hoc Thily lqi. [12] Nguyen Van Lai, Le Dirc Wan, Nguyen Quang Minh, Tinh toan truyen nhiet tren he thong song Tra tinh Thai Binh khi trung tam dien lvc Thai Binh lay nuerc lam mat, Trung tam thity van img dung va ks, thuot moi trtrong. [13] Pham Van Tien, Le Qu6c Huy, TrAn Duy Hien, Klnrang Van Hii, 2013, Ung dung mo hinh Mike 3 tinh town lan truyen nhiet trong nuerc bi'en khu vtrc nha may nhiet dien Quang Trach. Vien Khoa hoc Khi tuong They van va M6i trtremg-vu Khoa hoc va Cong nghe, BO Tai nguyen va Mei tnremg Assessing the Impact of Heated Cooling Water Discharge on the Intake of Thang Long Thermal Power Plant by MIKE 21FM Dang Dinh Ducl, Tran Ngoc Anh 1,2, Tran Ngoc Vinhl Center for Environmental Fluid Dynamics, VNU University of Science, 334 Nguyen Trai, Hanoi, Vietnam 2 VNU University of Science, 334 Nguyen Trai, Hanoi, Vietnam Abtracts: Nowadays, an increasing the number of thermal power plants have been built in Vietnam, especially in the provinces where are available coal resources such as Quang Ninh, Thai

11 66 D.D. floc va nnk. / Tgp chi Khoa hgc DHQGHN: Cac Khoa hgc Trai ddt vci Moi trtrang, rdp 32, Si; 3S (2016) Binh or Ninh Thuan. The study of assessing the impact of heated cooling water discharged from the outlet on the intake of thermal power plants is extremely necessary because of the temperature of water has significant fluence to the power of plant. According to the design, Thang Long Thermal Power Plant (TPP) (Le Loi commune, lioanh Bo district, Quang Ninh province) has cooling water outlet located at the upstream of Da Trang Bridge (on Man river) and has cooling water intake (inlet) situated at downstream from the outlet (near the main channel) [1.2]. Therefore, the author has applied the MIKE 21 model to simulate hydrodynamic and thermal transfer for the Thang Long thermal power plant. With range of water temperature larger than 8 C is negative for the power of plant, the results of study shows that the heated cooling water discharge in the river upstream has definitely impact to the intake of thermal power plant, especially, the most impacted is July with the total contravened time of 153 hours. Keywords: Mike 21FM, lan truyl nhiet, nh*