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KiTQUANGHliNCOU VA ONG DUNG XAY DU''''NG THUAT TOAN VA CHU QNG TRJNH TINH S6NG DU''''QNG TRONG KENH CUA TRAM THUY DIEN ThS Pham Thanh Nam ''''; KS Nguyin Ddv Hanh '''' Tim tat BSi bSo trinh bay tdm tit kit qui ng[.]
KiTQUANGHliNCOU VA ONG DUNG XAY DU'NG THUAT T O A N V A C H U - Q N G TRJNH TINH S N G DU'QNG TRONG KENH CUA TRAM THUY DIEN ThS Pham Thanh Nam '; KS Nguyin Ddv Hanh ' Tim tat: BSi bSo trinh bay tdm tit kit qui nghien cim xay dung thuat toSn vS chuong trinh tinh sdng duang (che khdng on djnh thay doi gap) kenh cda trgm thdy dign Thugt todn va chuang trinh tinh toSn nSy IS edng cg huv ich tra gidp eSc giing vien, sinh vidn vS ky su nganh XSy dung edng trinh thdy dSo tgo, nghidn ciru khoa hgc vS thiet ke cdng trinh Summary: This paper summarizes resutis on the algorthm and programme development for calculation of positive surge in channels of hydro power project (the rapidly change unsteady flow in open channel) The algorthm and programme will help engineers, lectures and students of the hydraulic structure department in trainning works, investigation and the design NhSn ngSy 10/8/2011; chinh sua 08/9/2011; chap nhdn dSng 30/9/2011 Dgt van de Trong edng tde linh todn va thiit k i cac trgm thiiy dien va nhifl difn, ngoai linh toan c h i df thiiy lye Irgng thdi dn djnh, cdn phdi giai quyet bdi loan ddng khdng dn djnh d cdc cdng trinh d i n nudc nhu kenh hd, dudng ham, giing diiu dp, dudng dng tudc bin va kenh xa Ody la bai loan phirc lgp Ve mat eg sd ly lufn, dd Id he phuang trinh vi phan ca ban cua ddng ehay (phuang trinh dpng lugng vd phugng trinh lien lyc), nhung vifc gill he phugng trinh ndy de dgt mire d f chinh xde yeu e l u thi edn phai Hip tye nghien cipu odi vdi ddng khdng dn djnh tren kenh hd eua trgm thuy difn (dgc bift Id sdng duang), mang bdn chit eiia sdng gidn dogn (ddng khdng dn djnh biin ddi glp) nen eae phuang trinh lidn tye vd phuang tfinh dpng lugng, md la sy djch chuyin eua sdng gidn doan, khdng phai la hf phuang trinh Saint-Venant, ma dugc viet cho mdl doan ddng chiy ed chira sdng gidn dogn Mpt sd eg quan tu v i n nude da thyc hifn viee tinh loan c h i dp khdng dn djnh dpc luyin ndng lugng cua trgm thiiy difn bang Microsoft Excel hoac viit chugng trinh tinh loan dgn gidn cho ttrng hgng myc cdng trinh, md chua d chugng trinh phin mim ddng bp Trong dd, nhu d u linh todn, thiil k i , thim tra, kiim djnh d e d n g tfinh thtiy dien, nhiel difn nude, khu vyc vd trgn qude te lien quan d i n bai lodn Ihtiy lye ddng khdng dn djnh thay ddi g l p dpc luyin nang lugng khdng ngirng tdng cao Bdi bdo ndy trinh bdy cac k i t q u i nghien cii-u xay dyng thuft loan d i viit chugng trinh phin m i m tinh todn sdng dugng cao nhit frong kenh dan cua trgm thiiy difn Thuft lodn va chugng trinh tinh lodn ndy Id d n g cy hO-u i d tfg giiip cdc giang vien, sinh vien vd ky su ngdnh Xdy dung d n g tfinh thiiy ddo tgo, nghien ctru khog hpc vd thiet k i edng trinh ' Khoa Cdng trinh thiiy Trudng Dai hoc XSy dung E-mail: giangnguyen9@yahoo.com TAP CHi KHOA HOC CONG NGHE XAY DUNG 5610/9-2011 57 KiTQUANGHliNCOU VA ONG DUNG Sdng kenh dan d a tram thuy difn - Cac phu>o>ng trinh ca l>an Thyc te ky ttiuft quan tdm den vifc xdc djnh eao tfinh ldn nhit d t h i hinh thdnh, kit qua d a vifc d t tai dot ngdt tren kenh dan, tir dd xde djnh dugc chieu cao cua tudng bdn eua kenh d i n , d i tfanh nude trdn khdi bd kenh Hinh dudi ddy md ta sy hinh thdnh vd phdt triin sdng dugng kdnh cd ma sdt, d t phy tdi dpt ngpt va todn bp Hinh 1-a the hifn trang thdi ctia ddng dn djnh ban day trgn kdnh din Dudng mat nudc vd tdn thit ma sdt da dugc tinh todn Khi d t phy tdi dft ngft, sdng xa dugng Idm ndng cao mue nudc ve phia thugng luu duge hinh thanh, nhu Hinh 1-b Theo nhu-ng quan sdt thdng thudng, mgt nudc ab g phia hg luu ctia day sdng gan nhu nam ngang Nhu vfy, dau sdng vugn den hd ehua, dudng mgt nudc tren todn bp chilu ddi kdnh se nim ngang (Hinh 1-c) Tuy nhien, the tich nudc bj tich Igi tren kenh d i n v i n tdng len d i n din se phdi di qug d i u sdng d i lap dly vdo khoang tugng irng vdl abc Do tdc dpng ndy vd dnh hudng ciia ma sdt, chieu cao sdng vd vfn tdc sdng se gidm r l t nhanh trdn dudng di din hd chti-a Hgn ttii nu-a, sdng vugn den hd chira, vfn tdc ctia ddng chiy kenh phli Ihl hifn sy giim d i n ttr gid trj eye dgi tgi hd chira den gid trj khdng tgi cudi kenh din, a dd khdng d n thdo luu lugng nu-a Ket q u i Id, nude se tich Igi den cao trinh Idn n h i l tgi cudi kdnh din (Hinh 1-d), ddi sau liic d i u sdng den hd chira [13], cpt nwirc vjn t6c Dirt-ng m0t msdi l-l6 chira Otrirng m$t nu-tyc cua sAng xi difo-ng dAu sbno vifcm wAgo t^OU) ^ Im (13) Tinh gid tfj Bo,,j, ttr d c phugng trinh tfen ta d : (14) o ( / ) = * + '«.(''o,o+AAo(/)) + Budc 2: Tinh Vs,o(ii) i l n thif hai theo cdng thirc: g"o.o J ^ go(,).A^o(,| S,0(ll) ^'otn (15) (0,o„ Thay gid trj Vs,o(ii) vdo phugng trinh d i linh Aho(ii)lln thti- hai theo cdng Ihii-e: ^otii) =- (16) 2m Tinh gid trj B L , , theo cdng thire: (17) K(ii) = ^o.o + "f-^otn) Tilp tye Ifp Igi trinh ty tinh todn nhu budc cho d i n cdc gid trj da tinh dugc Aho vd Vs,o d hai budc ke x l p xi bing (vgi sai sd cho phdp) thi dirng qud trinh lgp Od chinh Id hai gid trj ehlnh xdc can Hm ctia chieu eao sdng Aho vd vfn tde sdng Vs,o a thdi diim ban d i u , sau e l t phy ldi d f t ngfl vd hodn todn, lgi tuyin O ctia b l dp lye Cao trinh dinh sdng nghjch dugng sau d t phy tai dpi ngpt vd hodn todn, tgi tuyin O ctia be dp lyc: V'„=V„,+Ah^ (18) - Mddun 2: Xdc djnh Ahi vd Vs.i d- tuyen k i tiep vdi tuyin O ctia be dp lyc Logi d vfn ldc sdng Vsj, ttr d c phuong trinh tren, Itiay co„,, = (b + m.h„ „ ).h„ „ , vdi n = 1, ta d phuong trinh hf qui sau: ^43(5,„-i-m.AA,) {B,„+m.Ah,) (2/^„AQ, + V -V W, (19) ?«i,o + Budc 1: Gdn Ahi g v l phli cua phugng trinh (19), lan thip nhit, bing Aho da linh dugc d mddun 1, ttpc Id: Ahi VP (D = Aho, se linh dugc Ahi VT (D d ve trdi ctia (19), iln thip nhit; Gid tri W, dd dugc Hnh; Bi.o dugc tinh theo cdng thirc B, „ = (b + 2.m.h, „ ) + Budc 2: Tiip lyc gdn i l n thir hai Ah, VP OD = Ahi VT(I), se tinh dugc Ahi VT(III d ve trdi ctia (19), i l n thir hai TAP CHi KHOA HOC C O N G NGHE XAY DUNG 5610/9-2011 61 KiTQUANGHliNCOU VA ONG DONG Tiep lyc lap Igi trinh ty tinh toan cho cac budc tiip iheo, tuangtiJ-nhu budc 2, cho den gid trj eiia Ahi a hai ve ciia phugng trinh (19) x l p xi bang (vdi sai sd cho phdp) thi dirng qud trinh lap Dd ehinh Id gid trj ehinh xae d n Hm eiia chiiu eao sdng Ahi Thay gid trj Ahi vdo d c phuang trinh cd dgng (14) vd dang (6), se tinh dugc V^, + Bude 3: Tinh thdi gian truyin sdng nghjch dugng tip luyen O den luyin (Ali) Iheo d c phuong trinh da neu Lap Igi d c h tinh d mddun d i tinh chieu cao sdng Aha, vfn tde sdng Vs,2 t?i tuyin nam ke tiip vdi tuyin vd thdi gian truyen sdng tip tuyin d i n tuyen Ata Lam tiip lyc nhu vfy eho cdc tuyin sau den tuyin N d d i u kenh ndi vdi hd chti-a Tgi tuyen N, tinh dugc chieu cao sdng AhN Chii y ring, mac dii theo gia thiit Id sdng khdng d sue d n , ede kit q u i tinh todn ein phai thoi man diiu kifn sau: AA„ < A/,„_, ; ^Q„ > Aa_,; F, „ < K, „_,; A?„ > A/„_, (20) Thdi gian tmyin sdng nghjch dugng ttr luyin O tgi be dp lyc den luyen N tgi diu kdnh ndi vdi hd chira: T = YM,;n = \, ,N (21) n=l Cao trinh myc nude tgi tuyin N: V;,=V^,„ + A/i^ (22) dd: VN.O Id eao trinh myc nudc ban d i u eiia ddng dn djnh tgi tuyin N d dau kenh ndi vdi hd chira Cao trinh myc nudc lgi luyin N (VN) eung la eao tfinh myc nude lgi tuyen O (V^ ), ipng vdi luc t = T, tirc Id V^ = V^ Khi sdng nghjch duang truyin d i n tuyen N d d i u kenh ndi vdi hd chira, nd se bj phin xg, tgo thdnh sdng thufn dm, truyen xudng phia dudi, ve be dp luc Idm thip myc nudc Tuy nhien Iren thyc t i , sdng thufn dm Idm gidm myc nude ehi ton tgi (xult hifn) tren dogn diu kenh dan Sau dd, sdng thudn am suy thodi Idm denh mirc nudc len cao han cd eao trinh V^, tren dogn cudi cug kdnh dan Vi vfy, tinh toan eao trinh muc nudc bj denh ldn, Inh hudng (tdc dpng) eiia sdng thufn dm bj suy thodi, se gap nhieu khd khan o i tinh g i n dung, eoi thdi gian truyin sdng thuan am T' bang thdi gian truyin sdng nghjch duang T, (T' = T) vd cao trinh myc nude tgi be dp lye d quan hf tuyen tinh vdi thdi gian (Hinh 4) Tif dd, ta cd: ^o ^=n+[^o-%) (23) Theo (18): V,, = V^ „ -i- A/i^ , nen phuang trinh (23) trd ttianh: Vo,™«,=2V;;-V O) £ o- sf 0) c? , §'3!£-'6 5-c-^.o c c O -ro o o b-£ c ^0 ro S "c ' S -S £ ^ c £ -ro D)|_ o o ^ -* ^ c Si ID _" -ro 'X > i > ^• rt - ';9 o -ro Qo >, o Đ o ã^ã f -i c ã>; c -E ro _ o) c 1-ro ic-ro i±: 4(1) -ra Q) ^ E 2p o> • O O > — X ^ z CM X o ^ > 23 z z z CO Q -(l^ go)' 'tt! Zl to KiTQUANGHIiNCOO VA ONG DUNG Hodng Dinh Dung, Phgm Hong NhfL Vu Htru Hai, Nguyin Thugng Bing (1991), Tram thdy diin - CSc cdng trinh tren tuyin nSng lugng, Nxb Giao ttidng vgn t l i Hd Ndi Hd Sy Dy, Nguyin Duy Hgnh, Huynh Tan Lugng, Phan Ky Nam (2003), Cdng trinh tram thuy di$n, Nxb Xdy dyng, Hd Npi P.G Kixelep (1984), Si tay tinh toSn thdy luc (Luu Cdng Odo, Nguyin Tdi djch tir liing Nga), Nxb Ndng nghifp, Hd Npi Luu Di Try, Nhu Hifu Vu (1978), Nhung huhong cua cong trinh thdy cing - Phan Dinh Hde djch, Nxb Ndng nghifp lO.Vifn Khoa hpe vd Cdng nghf Cdng trinh thiiy (2010), Hd sg Ban ve thi cdng cdng trinh thtiy difn Td Lgi tinh Ldo Cai 11 M Hanif Chaudhry, Open - Channel flow PrenHce Hall, Englevi/ood Cliffs, Nevi/ Jersey 07632 12.Ven Te Chow, Ph.D, Open Channel Hydraulics, McGraw-Hill Companies, USA 13 Philip M Gerhart, Richard J.Gross, Fundamentals of Fluid Mechanies 14.Emil Mosonyi (1987), Low-Head power plants, Akadesmiai Kiadd Budapest TAP CHl KHOA HOC CONG NGHE XAY DUNG 5610/9-2011 65 ... sbng vnqn.il^l]6.Ch.i -VjiO (c) Hinh Su hinh thSnh vS phSt trien sdng xa duang trdn kinh cd ma sdf Trong thiil k i kenh d i n cua trgm thuy difn d n thiel phai xdc djnh ede tfj sd ldn nhil vd nhd... ehiiu ddng ehay vdi vfn ldc ban dau Vo va chieu sdu ban d i u Id ho V f n tdc sau sdng di qua (trong pham vi sdng) Id V (Mui ten lien net tuang irng vdi sdng thufn chiiu ctia vfn tde sdng trimg... lugng eiia ddng ehay ban d i u Qo = Vo.cuo vd gid trj luu lygng cua ddng chdy sau sdng di qua (trong vimg sdng) g = K.((»„ + A / i '' ) , la cd phygng tfinh xde djnh luu lugng sdng: ^Q = Q„-Q