I KHOAHQC MAIJMJM'''' IJM DANH GIA DAC TINH PHAN T 4NG M,4N X I N G CUA S 6 N G vt'''' QUA SO LIEU TH^rC OO VA CONG THUC THVC NGHIE Do Die Hai Vifn Khoa hgc Thuy Icri miin Nam Tdm Wit Dgc linh phan tdng mdn[.]
I KHOAHQC MAIJMJM'IJM DANH GIA DAC TINH PHAN T.4NG M,4N X I N G CUA S N G QUA SO LIEU TH^rC OO VA CONG THUC THVC NGHIE vt' Do Die Hai Vifn Khoa hgc Thuy Icri miin Nam Tdm Wit: Dgc linh phan tdng mdn da mpt cua sdng phv thudc vdo chi dp ddng chay my vd ddng chdy thuy Iriiu Phdn lich dgc linh phdn tdng cd the dtfa vdo sd lieu thuc dng vdi cdc cdng Ihuc gidi lich kinh nghifm hogc md hinh todn 3D hay 2DV Trang npi dung bdi bdo n^ buac ddu xdc dinh dugc ddc linh phdn ldng man da cm song Hgu qua cdc sd itfu thtfc man Iheo chliu sdu ddng chdy Kit qud nghien ctiu ban ddu ndy hy vpng se md mpt hu&ng nghien ciru mdi vi ca chi phdn ldng mgn cho cdi- cira sdng ven bien DBSCL de phl/c vti nhu cdu lay nudc nggi (hot ngpt) cho ndng nghifp hay nudc sinh hogt hodc lay nudc mgn la tdng day cho nudi trdng thdy sdn Tir khda: Xdm nhgp man ndng dp mgn phdn ldng mgn, cira song Hgu, nhdnh Dinh An, nhdnh Trdn Di, trieu len (HWS) trieu xudng iLWSh Summar\: The salinity slralification feature of an estuary depends on the regime of river and tidal flow Stratification feature analysis can be based on actual observed data with empirical analytical formulas or 3D or 2DV mathematical models In the content of this paper, initial characteristic of salinity siratificalion ofthe Hau estuary are initially determined through actual salinity observed data according lo the water depth This initial research resuh is expected to introduce a new research approach about the salinity stratification mechanism for Ihe coastal estuaries of the Mekong Delta to ser\e the need of fresh water intake (fresh water taking) for agriculture or domestic water or take brackish saline water bottom for aquaculture growing Keywords: Saline intrusion, salinity concenlration salinity stratification, Hau estuary, Dinh An branch, Tran De branch, high tide (HWS) low tide (L WS) f>^T VAN Dfe Xim nhjp mjn tai viing ciia sdng cd quan h? mJt thiel vdi chi dg thuy ddng lyc hgc Cic pha ttuydn mjin ttong sdng biiu thi sy can bing giiia hai ddng chiy ngugc chidu nhau, vdi mgt bdn li lugng nudc nggt diy thoit ciia sdng va mdt ben la thuy ttidu dua mjn vio ciing vdi sy khuyich tin ciia nudc mjn tu noi cd ndng dg cao tdi noi cd ning dd thip, tyo mOt dudng quan hd dd dgc sdng ed dang ham mu, tit din vao phia ttong, cd dao ddng ldn xuing tuong irng vdi ddng ttidu, *.°° ' " ' ^'^ ^°}'™ """"S cua sdng luu lugng ™ " ' ^hi ttuyen vao ttong sdng, hidn higng l^uyech tin ddng mgt vai tto quanttgngttong ^'.^ ''"^ " * '™ " ^ hon vi tda toin mJt "=*' ^f "S *eo khdng gian vi thdi gian Vd ly ^^^ "™ 0,7 xao Irpn >cu cd phan lang; q = 0,2 - 0,5 xao Iron vira ban phan day Va la \an tde ddng cue dai giai doan tang (phan lang mdt sd trudng hop theo thiiy trieu trung binh tren mat cat d cira ra), a thdi gian, thdi doan) va q < 0,1: xao iron manh la thdng sd Ihiiy trieu lu da dupc dieu chinh; sd cira sdng dugc de xuat bdi M Thatcher va D va khdng the hinh mat phan lang Hareld [3]: Ngoai ra, vdi muc dich xac djnh loai pha trdn thang dimg va ban chat ciia su phan tang nudc E = ^ = - " (5) l^P/Pm d cua vao ngudn nudc, mdt sd lieu chi duoc 1^0 tir so dd phan tang Hansen - Rattry [3] He sd cira sdng Richardson de xuat cua H va mdt sd tieu chi thiiy van Fisher vao nam 1972; sd ldp Richardson dupc Trude het, cac tieu chi nhu vay bao gdm sd Froude mat dp dupc su dung rdng rai Irong cac CO che thiiy l^c ciia ddng chay phan tang ^'•"^"dS^'" Trong dd: (4) de xuat bdi K Dyer va A New [3]: Rii =gh^p/V^p^ vaRii •Ftf (6) Xao trdn manh va phan lang yeu tuong ung vdi RiL >2; Xao trpn mdt phan va phan tang trung binh, RiL thay ddi tir den 20; va Xao trdn yeu va phan tang manh, nem nudc man K\\_ > 20 TAP CHl KHOA HOC VA C O N G N G H ^ THUY LOl SO 59 - 2020 37 KHOA HOC zmnni Bang I: Mpi sd tieu chi \ a c djnh kha nin? phan t i n g m i n i iing cira s d n j Phan loai Xao trpn 111 E.- Phan ^.^^ ' ^ " hoan toan Ydu-Y ; (WI.1 i (M).l ' lung phin bmh -TB i Xao udn ylu (Phan ling) Manh \ ! (NCm mui*->! I 1.0-2.0* I II >U.^ >1 2.4 Lira chpn cong thtrc tinh toan Cac cdng thiic giai nch de xac dinh co che phan ting cho cac nhanh >dng d i dupc ^lai thieu d tren cd the ap dung cho cac nhanh sdng viing anh hudng tneu thupe DBSCL tu> nhien dp chinh xac phu thupe \ a o sd lieu dau vao cho cac cdng thirc tinh toan Trong nghien cim na> cac sd lieu A^c m$n thuc te tai hien trudng theo chieu siu ddng cha\ tren hai nhanh cua ^one Hau nim 2016 si diing de tinh toan danh gia kha ning phan tang 2.5 T i i lifu dung nghien cuu Trong cong diiic (1) danh gia phin tang theo tham ^o n phu thudc vao so lieu man ihuc ic ngoai hien uudng theo phuong dimg cua ddng cha> (do tang mit \ a tang da>) viec k-^i.^ sat m?in iheo chieu sau ddng cha> la rat q^ar: trpng nghien cim danh gia su phan u r g ciing nhu dimg phin loai cira sdng So lieu man ihuc iheo phan tang dimg irong n ^ i e n cim na\ dupc ke thira tir cac tai lieu khao sal dac khao sat cua nhdm nghien cim thupe \'ien Khoa hpc Thuy lpi mien Nam v i nhdm n ^ i e n cuu ihupc dai hpc L'lrechi (Ha Lan) thuc hien \ a o ihang Ii'.'^ Trong dpi khao sal na\ da nen hanh ddng ihdi ndng dp m | n theo chieu sau ciia ddng chay dpc theo nhanh sdng Hau (Tran D^ \ a Dinh \n) theo qua trinh kni tneu len \ a trieu xudng Bd tri 38 :o ca nd cha\ dpc uen hai nhanh sdng cung mdt ihdi diem E>o trieu len: Ca nd \uai phai tir cua sdng thu\ tneu iai cua song dat dinh thi lien hanh man phan bd theo chieu sau (mdi \ i tri trung binh khoang u gia tri) xong \ i tri thu nhat ca nd cha\ den vi tri thii hai each \j Ul ihit nhit khoang 3-4km iioc dp chay ca nd bing tde dp uu\en trieu khoang jOkmli) den \ i tri thir lai tiep tuc man nhu \ i tri thir nhat \ a cir iicp nic lip lai cho ddn \ i iri cudi ciing (cu lao Ma> - Cai Rane) Do tneu xudng Ngupc lai vdi quy Uinh luc trieu len ca nd xuit phat tir cii lao Ma\ Cai Ring uieu bit diu xudng thi m i n theo chieu sau (mdi \i ui uung binh khoang 10 gia m phan bd theo c h i k sau) xong \i ui thit nhit (dau tien) ca nd cha% d^n vi tri thli hai each \ j tri thu nhit khoang 3-4km (tde dp cha> ca nd bang tde dp meu 30km h | d^^ vi Ul thli lai tidp tuc man nhu vi iri ihu nhit ^a cu uep tuc lap Iai c)io d6n vi tri cudi ciing (cira bien) [1] Tir kdt qua khao sal dac man la, hien tnione cho tha> lai cac vi ui c6 su tha> doi xl nmg man Iheo chieu , i a dong chiv lai lii ca cac M tri khao sal n,> nhien de danh a a mirc dp phan tang iren song ha\ tai timo ~^ sdng Ihi cin tinh loan ihco ihone sd n K • " thiicdi TAP CHl KHOA HOC VA C O N G N G H £ T V I O Y LOI S 59 - 2020 e»"tuc„„g IHECSS KHOA HOC Ket qud man Sa hoa luyen khdo sdt man Hinh 3: Mmh hoa so lieu vd ket qud thuc man ndm 2016 KET QUA TINH TOAN VA THAO LIAN Tir ket qua thuc man theo chieu dirng (tang mat va tang day) tai tCrng vj tri dpc theo cac nhanh sdng Hau thdi gian tir 3I/3/2QI6 ddn 01/4/2016 tinh loan dugc tham sd (n) cho nhanh sdng Hau trieu len \a tneu xudng nhu sau: 3.1 Ket qua rinh toan tham so n tren nhanh Oinh An Khi trieu len (HWS) tren nhanh sdng Hau cua Dinh An dugc khao sal man lir cira sdng (cira Dinh An) ngupc len thuang luu tren chieu dai khoang gan 40 km vdi 14 diem do, mdi diem each khoang 3,0km Bang 2: Ket qua dac va tinh toan tham so n nhinh Dinh An (ngay 31/3/2016) - H\\ S \ ' | Iridiemdo DOI D02 DOI Dot D05 U06 D07 DOS D09 DIO DII DI2 Dli D14 12:09 1222 12:31 I2'44 1253 39,0 Thm g u n Thong 9:20 i 9.19 10.00 10 14 10:34 1100 11:15 1130 I 11:54 Khoiina each iCr bien L (km) 1.1 5,9 9.0 11,9 1.5.1 18.0 21.0 24.0 27.0 30.0 3.3.1 36,1 S,,, 22.80 22.6.'i 22.15 2080 I7.S(I 15.75 14.10 12.65 11.65 10.55 9.19 6.53 4,17 2.32 5.„ 9.77 S.» 6.76 5.89 4.59 3.82 3.80 3,65 1.85 3.45 2.12 1,65 1.17 0.33 s 16.29 15.56 14.45 I.1 14 11.20 9.79 8,95 8.15 , 7.75 7.00 5.66 4,09 2.67 1.32 \S 1.1.0.1 14.19 15.40 14.92 1.1,21 11.93 I0 30 9.00 "SI 7,11 7.07 4,89 3,(X) 1,99 aso 0,91 1,07 1,12 /.IS 1,22 I.IS 1,10 I.OI 1,02 1,23 1,20 1,12 IJl a P.loai TB M TAP CHi KHOA HOC VA CONG NGHE THUY LOI SO 59 - 2020 KHOAHQC MB3!3!BIIH ã >ô>ô*L Hinh 4: Biiu quan hfnvaL nhanh Djnh An 31/3/2019 - HWS Bing 3: Idt qui d y vt tinh totB thrnn ti B - nhinh Bjnh An ngiy 01/4/2016 - HWS Vioidi^do m DOI Ttm DM DOS D06 007 I 008 009 DIO DII DI2 DI3 an 14:02 14:11 14:20 DI4 llibipaido 12:2s 12.40 12J0 1239 13419 13:19 I3J7 I3J6 13:45 142 Kboi«ciditlibi&L(bii) 2.91 5JI iSt 11.76 14.88 17.83 nm 23j8 26.93 29« 32.99 3552 31.8 S 22.75 HM 22.40 21.85 3080 I7J0 15.95 15,45 I4J0 12.10 13J5 11.60 9.81 7.26 s_ 8J8 7.97 5.72 Ul 5.11 1.17 2.86 Its 2J9 2.43 1.74 IM 1.70 1J8 s /^s 15j6 IS.28 I4j06 l4jQS 12.95 I0J4 9.41 9X17 8J9 7J7 7J5 6.62 5.75 4J2 I4J8 I4A4 I6i«8 I5J4 15,70 MJ3 13.09 12.76 ll;62 9*7 11.61 9.96 8.12 5.88 US! Him U9 IJf A* /.« IJt '.33 LSt /Ji7 1.41 /JW Abif Lie Ul M IB Q u a kf • T* L OJCO 0.00 SJOO Ct tm, 10.00 15.00 20.00 LII—) 25.00 30J10 35J)o ^QQ, S*, Hinh 5: Bieu dd quan hfnvdL nhdnh Dfnh An ngdy 01/4/2019 - HWS lUii tri^u xudng (LWS) Iren nhinh song H|u ciia Djnh An dugc khio sit m$n tu thugng luu d^n ciia sdng (cua Djnh An) 40 trio chiSu dii khoing gin 34 )„„ ^ivoi ' 12 diem do, moi di£m cich nhan kh toing 3,0km TAP CHi KHOA HOC VA CONG NGHE m O r m l a ) » 2020 I KHOA HOC iM.t.i;!ci;i;!!r^ Bang 4: Ket qua dac vi tinh toan tham so n - nhanh Djnh \ n ngij 31/3/2016 - LWS Vl In diem TTi6ngs6 s s AS n PJofi DOI D02 003 D(M D05 D06 D07 i DOS Tlwi gun 15:10 15 21 15 31 L5-49 1608 1639 , 1649 | r02 r 19 17:32 17 48 18.00 23.75 10.80 17.28 12.95 0,75 1,29 2.1,10 6,20 22,90 7,95 1.5,52 15.16 0,98 6,52 14,71 16,38 9,32 22,.30 4.82 13,56 17,48 Khoans cath [Lf b]^n L (Ijii 15.30 12,31 18,13 21,16 13,40 21,25 20.05 15,65 4.62 4.32 4.12 4.12 12.94 12,18 9,89 8.76 15,74 11.53 9.29 16,63 24.20 12,75 56 S.15 27.24 11.45 3,02 7.24 9,20 33.41 7.48 1.39 4.43 6.09 1,11 1.29 8,43 1,17 10,40 10.50 2.23 6,.37 8.27 1,30 1,37 1J9 1,29 1,17 TB 1,06 im 1,13 DIO DII DI2 M Hinh 6: Bieu quan he n vd L nhanh Dinh An ngdy 31/3/2019 - LWS Bang 5: Ket qua dac va tinh toan tham so n - nhanh Dinh An 01/4/2016 - LWS V i l n diem DOI D02 D03 DM DOS D06 D07 D08 DIS DIO DM DI2 18 05 14:43 Then gian Thong so 17:00 17:11 17:19 17,28 17.19 18:14 18,23 18.13 5.8 8,9 11,8 14.9 17.9 20.9 23.9 26.9 29.9 33,0 22.45 22,30 21,90 21.20 18.50 15.40 14.95 14.40 13,70 11,65 I7:.50 | 17:57 | Khoang each lir bien L ( k m l s,, s s 23,10 9,74 3,0 22,60 9,15 6.59 5,79 3,93 3.57 3,26 2.96 2,82 2.24 2,08 2,05 16,42 15.87 14.52 14,05 12,91 12,39 10,88 9.18 8,89 8„12 7,89 6,85 AS n 1.3,.17 13.46 15,87 16,51 17,98 17.63 15.24 12.45 12,13 12.16 11,62 9.60 0,!l 0,S5 1,09 1,1S 1,39 1,42 1,40 1.36 1,37 1,46 1,47 1,40 PJa/u TB M Hinh 7: Biiu quan he n vd L nhdnh Dinh An ngdy 01/4/2019 - LWS TAP CHi KHOA HOC VA C O N G N G H E THUY LOI S 59 - 2020 41 I KHOAHQC MJ.1., khoing cich t?i viing ciia sdng cich biin ut 3-4kni phSn ting trung binh v i tir 4-40km phin ling khim^ Dinh gii kit qui tndi loan lien nhinh Djnh An: Tu ket qui tinh toin tham so n cho thiy uen nhinh Djnh An ciia song H$u xuit h i ^ h i ^ tucmg phin ting Hifu Ifn tii Uung binh cho din m^nh c i tmong h^p triiu len v i uieu xudng J Kit q u i tinh toin tham s6 n tren nhinh Kit qui tinh toin s o bp hi$n tugrng phin ting thai ky triiu len c6 xu dii ting din til cijra song Ite thUQng luu, 1^ viing cua song cich biin tilr 3-4 km phan ting bung binh v i tii 4-40 km phan ting m^nh TrinDl Tuong HI nhu nhinh Djnh An, nhinh Tiin D i ciing tinh toin cho hai thdi dojin la triiu I6n v i triiu xudng Khi triiu 16n (HWS): dpc nhinh Trin d i vdi 12 diim dpc theo sdng vdi chiiu dii khoing 33kra tir ciia Trin D i len h i t C i Lao Dung Khi triiu xuing kil qui cho thiy ciing xuat hi^n h i ^ tucmg phin ting v i phin b i khong gian theo chieu dpc sdng gan nhu tuong dong Bing 6: Kit q u i dfc v i tinh toin tham si n - nhinh Trin D i ngiy 31/3/2016- HWS V l Iri dicm T02 T03 TOI TOI TII5 T06 T07 | T08 T09 TIP Til T12 Thoi ian ThOng s6 j 9:14 9J5 9:39 9:44 9:54 1003 10:13 10:22 10:32 10:41 10:50 10:59 32,8 Khoinci:Mili>u6iL(1aii) 2.9 5.9 8.9 11.8 14.8 17,8 20.9 24.0 26,8 29,8 s 16.S5 15.80 14.90 14.80 UjOS 12.10 11.55 11.05 9.19 8,28 4,33 1,50 s„ 12.65 1IJ5 11.40 9.81 5J5 4.10 4.12 1,70 3J4 2.61 2,15 1,19 s 14,75 13.53 13.15 12,31 9.65 8.10 7,83 6.38 6.26 5,44 3.24 1,35 AS 4J0 4J5 iX 4.99 8.80 8j00 7,44 9.35 5.85 5.67 2.19 0,31 s 021 H34 027 041 Ofl 099 09S 1,47 093 1,04 0,67 M M PJoti W 0,23 m Qnan hf n vJt L 40.0 8*M Htnh 8: Bieu quan hfnvdL 42 nhdnh Trdn De 31/3/20 J - HWS T ^ CH( KHOA HOC V A C O N G N G H ? THUY Lpi 5(5 - 2 KHOA HOC CONG NGHE BiDE 7: Kit qoi dfc vi tinh toin tham so i - nhinh Tran Be ngiy 01/4/2016 - HWS Vitri d l ^ A) TOI T02 T03 m T05 T08 T09 T10 TH T12 12:47 13:14 13:25 13J8 ,3:53 I4M 14:23 T06 11:46 12:05 12:14 s6 T07 T1)6i gian TbOog 12:27 12:37 KhokKcichtlrbi^nL (km) 3,1 6,0 9J 12,4 15,4 18,5 21,6 24,4 27,2 30,3 33,7 S„ 18,30 16,65 16,35 14.65 13.00 11,40 9,70 8,85 9.10 8,35 7.25 3.65 s„ 12.20 12.70 12,60 11,02 10,15 8.95 6,00 5,00 4,00 4,05 3,25 2.05 s 15,25 14.68 14,48 12,84 11,58 10.18 7.85 6,93 6,55 6,20 5,25 2,85 AS n 6.10 3,95 3,75 3,63 2,85 2,45 3,70 3.85 5.10 4.30 4,00 1,60 0,40 0,27 0,26 0,2S 025 0J4 047 IB 056 0^ 0,69 0,76 056 PJoil Qtmam h^ n v l I 0.90 • 0.70 0.60 0.30 0.40 030 0.20 0.10 \ « ^ s\^ % 13.00 s,oo 20.00 CAasOag 30j00 25J0O 33.00 40.00 I On*) Hinh 9: Biiu dd quan henvdL nhdnh Trdn De ngdy 01/4/2019 - HWS Khi trifiu xu6ng (LWS): tr6n nhdnh song H§u cua Trln De cung dugrc khao sat m§n tir thuemg luu din cua s6ng (ciia Trin DS) trfin chieu dai khodng gan 33km vai 12 dilm do, mfii dilm cdch khoang 3,0km Bing 8: Kit qui dfc v i tfnh toin tham so n • nhinh Tran De, ngiy 31/3/2016 - LWS Vitri diem TOI T02 T03 T05 T06 Tff7 T08 T04 T09 TIO Til T12 15:58 16:08 16:17 16:26 Timieiando Tli6ng 14:38 14:48 14:59 15:P8 15:17 15:27 I 15:37 I 15:49 Khoang each tir bien L (kml 0,00 3.04 6.05 9,29 12.41 15.39 18.39 21.40 24J7 27,17 30,30 33.26 18.25 16.45 16.15 15.35 15.20 12,90 11.60 10.95 10.40 8,76 7,84 3.21 S™, 14.45 12.75 12,10 10.70 6,33 5.10 4,16 3.80 3.27 2,03 1,34 0.77 s 16.35 14,60 14.13 13.03 10.76 9.00 7,88 7.38 6.83 5.40 4.59 1.99 4S 3.80 3,70 4,P5 4,65 8.88 7.80 7,44 7.15 7,14 6.73 6.50 2.44 ir 023 02! 029 036 012 0S7 0,94 0,P7 1.04 1,25 1,42 1,22 PJcui TB M TAP CHl KHOA HOC VA CONG NGHE T H O Y LOI S 59 - 2020 43 KHOAHQC Qaaa kt • • • I- Htnh 10: Biiu dd quan hfnvdL nhdnh Trdn Di ngdy 31/3/2019 - L WS Bing 9: Kit qui df c vi tinh toin tham si n - nhinh Trin Bi, ngiy 01/4/2016 -LWS Vlnidi&iido TOI TTO va To» T05 T06 TOJ T08 T09 TIO Til T12 T13 T14 Thtu eian TMng 17:30 17:38 17:45 17:53 18:00 3.0 6.2 9.4 114 15.4 I8J 21.3 24.4 27.1 32J 34,7 37,7 40,6 18.80 16.90 16.80 14.95 13.90 12.40 9.80 9.08 8.78 8.17 6.84 6,50 5,52 4,80 I4J5 12.95 12.80 11.05 9.99 8J3 6.61 5J9 4J0 3.41 2,18 2.26 0,89 0,78 16.63 14.93 14.80 1.1.00 11.94 10_36 8.22 7.34 6.49 5.79 4.51 4,38 33) 2,79 4.25 3.95 4.0O 3.90j 3.92 4.08 3.16 3.49 4J8 4.76 4.66 4,24 4,62 4,02 026 026 027 03O 033 039 TB OJi; 04S 071 0S2 1,03 097 1,44 1.44 16:04 16:13 , 16:21 16:34 16:45 16J6 I7fl5 17,13 17:22 KhoiiiKC^Ii tir bien L (km) s>, ss ^ B PJotI M Qmmm hf B va L Hinh II: Bieu dd quan hfnvdL nhdnh Trdn Di ngdy 0I/4/20I9 - LWS Dinh gii kit qui tinh loan hen nhinh Trin Di Kit qua tfah toin cho thiy tSi sdng H|u-nhinh Tlin Di cd thi xiy la hi?n Wpng phan ting tnmg binh uong chu ky hiiu len nen loin bp 44 chiiu dii xim nh$p khao sit ndinil 35km tir b i ^ vio), mjc du cd vj tri cd hita t ^ pMn tang m?nh nhung xdt irt„ sudt chiiu dii thi khdng cd ning hbA thinh nem m ^ TAPCHlKHOAHQCVAC6NGNGHfTHOYLOIS