KHOA HOC CONG NGHE
So 05/2020
Nghien cuu che tao mang dong chay
• PGS. TS. D A O V A N T U A N - Trudng Dal hgc Hang hdi Viet Nam
TOM TAT: Npi dung bai bao trinh bay nguyen ly cau tao mang ddng chly, he thong dieu khien va tinh toan lua chpn may bom.
T u KHOA: Mang dong chly, mo hinh vat ly thuy lyc, tinh toan may bam, dieu khien may bom, nghien cuu dong chay
ABSTRACT: The content of the paper presents the principle of flow flume, control system and calculation of selected pumps.
KEYWORDS. Flow flume, hydraulic physical model, pump calculations, pump controller, flow research
l . O A T V A N O i
Nghien cdu ve thuy lUc, thUc nghiem ddng mdt vai trd quan trpng, vl eho tdi nay hau het mgi van de do thuc tien de ra deu chUa hoan toan cd the g i l l quyet bSng thuan tuy ly thuyet (md hmh toan). De xae dinh cac dae trUng ddng hgc, cO cau ddng chay, tac dung eda ddngchay tdi vat can, chuyen ddng bun cat..., ngudi ta dung m I n g ddng chly de thi nghiem, vi du:
Nghien cdu ddng chly qua dap tran ed hinh dang khae nhau:
Hinh 1.1: Dong ehiy qua dap tran Nghien cdu l u e t i c dpng cua dong chly 'erivat c i n :
Hinh 1.2: Tic dung eda ddng ehiy lin vat cin Nghien cdu nudc nhay:
Hinh 1.3: Nghien euu nudc nhay Viee nghien cdu che tao mang ddng chly t d kich thudc nhd den kich thude Idn, vdi he thdng dieu khien lUu luong hien dai eho phep tao ra cac tdc do ddng chly khae nhau d nudc ngoai da ed eae san pham thuong mai, tuy nhien trong nude viee nghien edu san xuat mang ddng chly chUa duge thUc hien, viec nghien cdu che tao mang ddng chly la can thiet de ndi dja hda.
2. T 6 N G QUAN M A N G D O N G CHAY Mang ddng ehay thudng dUOc ehia thanh ba loai theo kich cd: nhd, trung binh, Idn, mdt sd mang ddng chay thuang mai ed the ke den nhU:
Mang ddng chly kieh thudc nhd ed mang H-6530 cLia Cdng ty Hampdel My vdi kich thUde dai 3,66m, rdng 0,15m, cao 0,31m, dugc lam bang ninox va kinh cudng lye, he thdng bom bien tan tuan hoan nUdc, dung dien 3pha'20aV.
Hinh 2.1: Mang ddng chay H-6530 eua Cong ty Hampdel M i n g ddng ehay kich thUdc trung binh cd mIng HF530 cua Cdng ty ESSOM (Thai Lan} vdi kieh thudc kich thude: dai 5m, 7,5m,10m va 12m, rdng 0,3m, cao 0,45m, duge lam bang ninox va kfnh cUdng lyc, he thdng bom bien tan tuan hoan nyde, dung dien 3 pha 380V.
.•. iV
Hinh 2.2: Ming ddng ehiy HF530 cua Cdng ty ESSOM (Thil Lan)
101
KHOA HOC CONG NGHE
So 05/2020
Mang ddng chay kfch thydc Idn ed mang GOTT- MPTF01 eua Cdng ty GOTT Malaysia vdi kfeh thudc kfch thude: dai 5m, 7,5m,10m, 12m, mat c i t ngang ed cae phuong I n : rdng 0,3m, eao 0,45m; rgng 0,6 cao 0,6m va rdng 1,0m, cao 1,0m.
Hinh 2.3: Ming ddng ehiy GOTT-MPTFOl eua Malaysia Mang ddng chly kich thude nhd chi duoc dung nhu giao cy true quan ve ddng chay, mang ddng chay kieh thudc trung binh va Idn dugc dung nhu cac thiet bj de nghien cdu khoa hge ve ddng chly.
3. NGUYEN LV C A U TAO M A N G D O N G C H A Y Qua nghien cdu tai lieu ve m I n g ddng chly va cac thiet bi mang ddng chay tai cac trung tam thf nghiem va eac san pham thuong mai.
Nguyen ly cau tao cua mang ddng chly gdm 4 phan CO b i n :
- M i n g ddng chly: Mang nUde cd Idng dan hinh chd nhat ed ket cau khung thep va kinh eudng lUe (de quan sat hinh dang ddng chly) de cho nude chay t d dau nay den dau kia.
- Be nudc hai dau: La noi nhan va va thao nUde ciia mang nude nude lUu luong eho va nhan eiia hai be nude hai dau b i n g nhau do he thdng bom tuan hoan khep kfn. Ket cau cua be nudc hai dau dugc lam bang tdn thep.
- Khdi dieu khien may bOm gdm: PLC, bien tan va c i e e l m bien ap suat (suy ra lUu lugng), man hinh e l m dng vao sd lieu, chuong trinh dieu khien de kiem soat luu lugng tao ra ddng chay ed gia tri x i e dinh trong mang.
- He thdng bdm: Bao gom may bOm va he thdng dng dan.
Hinh 3.1: Cau tao tong the ming ddng ehiy Nguyen ly hoat ddng cua mang ddng chly hoat ddng nhu sau:
- Ddng chay sexuat hien trong mang ddng chly do cd dp chenh muc nudc hai dau nhutrong kenh h d t u nhien.
- He thdng bom t u i n hoan cap nUdc cho be thUOng luu va hut nudc trong be ha lUu tao ra dd chenh miic nudc hai dau.
- Chuang trinh dieu khien he thdng bom tiep nhan g i i tri van toe ddng chly duge vao t d man hinh, gia trj cam bien ap suat xac djnh dugc luu luong trong ong dan va dieu khien bien tan sao cho may bom dat gia trj lUu lugng yeu cau.
4. TiNH T O A N CONG SUAT M A Y B O M De d i m b i o he thdng bom nUdc tuan hoan dap dng dugc yeu eau van tdc ddng chay trong mang vdi ehieu sau ddng ehiy da biet can xac dinh cdng suat may bom de lya chon may bam phu hgp dap dng dugc luu lugng bom. Vdi kfch thUdc mang ddng chly, chieu sau nudc va van tdc ddng chay biet trUdc xae djnh ddoe lUu luong can bom.
May bom can phai tao dugc cdt I p Idn hon ton that eye bd va ehieu dai trong dUdng ong day, dUdng ong hut, dng Venturi va do chenh mye nude hai dau mang.
Trong thUc te, do chenh mUe nude hai dau eua mIng ddng ehay coi nhU bang 0 vi cao trinh mUc nUdc gan bang nhau.
Tdng tdn that edt nUde chieu dai xae djnh theo cdng thdc:
^ d 2,0 Trong do:
d - Dudng kfnh dng;
A - He sd ein, xac dinh theo cdng thdc AD. Altsul:
/!, . fins 0:25
A = 0 , l l ( ^ - F - )
\ d Re/
v - Van toe ddng chay trong dng;
L^, - Chieu dai dng day;
L,^^,- Chieu dai dng hut.
Tdng ton that edt nUde cue bd xae djnh theo cdng thdc:
Trong do:
i,. - He sd can cue bd khi vao dng hut;
^,^- He sd can cue bd dau ra cda ong day;
i.^.^- He sd ein cue bd doan ong udn cong;
^^- He sd c i n cue bd cua ong Venturi.
Cac he so can cyc bp xac dinh nhusau:
Cda vao d n g :
NWWW KNWW' / ^ '19
r^ r
Hinh 4.1: Trudng hpp cua vao: rat thuan; mip sie: mip trdn - Mep trdn rat thuan: i.^ = 0,05;
-Mep sac: ^^ = 0,50;
-Mep trdn: ^^ = 0,20, Mieng radng:
102
XWWN w1 ^Vl
Hinh 4.2: Trudng hpp tinh toin eua ra
^' " [ ' " § ) '<hiO»a) thU^=1
6 n g trdn, udn thanh gdc a:
Bing 4.1. Bing tra he so ton thit eiia ong trdn uon thanh gde a a
%
30"
1,2 40"
0,3 50°
0,44 60"
0,55 70°
0,74 80"
0,90 90"
1,10
B^flT
K L ^
su
N = ^ Hinh 4.3: Uon thinh gdc 90f Cdt ap cua may bom xac djnh theo cdng thdc:
H^ = h^-Hh^
Cdng suat may bOm can p h l i Idn hon cdng suat xae djnh theo cdng thde sau:
__y-fl„-Q Trong dd:
Y-Trong lugng neng cua nUde;
Q-LUu lugng bom;
n^-Hieu suat bom;
n^^ - Hieu suat ddng co.
5. HE T H 6 N G DIEU KHI^N MAY BOM De tao ra mdt he thdng nude chly tuan h o i n can cd he thdng dieu khien luu luong thdng qua dieu khien bom. Cau true eua he thdng dieu khien lUu lugng duge m d t a nhu hinh sau:
Hinh 5.1: Cau true eda he thong dieu khien luu lupng Cae thanh phan cua eau true gdm:
-Thiet bi do lUu lUong: do luu lugng cua nude chly trong dUdng dng (dng Venturi);
KHOA HOC CONG NGHE
$605/2020 - Bd dieu khien: ThUc hien dieu khien gia trj luu lugng qua dudng dng;
- Bien tan: Dieu khien tdc do ddng co;
- Bom: Thiet bi tryc tidp thay doi lUu lugng tren dudng dng;
- HMI: Man hinh giao tiep gida ngudi va may.
Viee dieu khien luu lugng dUoe hoat ddng vdi cau true tren duge thUe hien nhu sau: Dau tien, lUu luong tren dudng dng duge do bang thiet bj do (dng Venturi) va gia tri do dugc gdi ve bd dieu khien. Tiep dd, bd dieu khien ket hgp vdi gia tn luu lugng dat trude cua ngUdi van hanh t d man hinh HMI de tinh ra sai lech dieu khien.
Sai lech dieu khien nay duac dUa vao bd dieu khien PID de tinh toan gia tri dieu khien. Dau ra bd dieu khien PID duge gdi tdi bien tan de thay ddi tdc do ddng co bom.
Thong qua viec thay doi tdc do bOm, luu lUOng se dieu khien den khi dat dugc g i i trj dat mong mudn. Thuat toan dieu khien dugc neu theo so dd dUdi day:
Hmh 5.2: Thuat toan dieu khien 6. SAN PHAM CH^TAO THOT NGHI|M 6.1. Ket cau mang dong chay
Mang ddng chay ehe tao thd nghiem la loai ed kfeh thude trung binh ed kfeh thUdc: dai 5m, rdng 0,3, cao 0,5m dugc lam bang he thdng khung thep hinh va kfnh eUdng lde. Be nUde hai dau dai 0,5, rdng 0,3m, cao 1,2m dugc lam bang he thong khung thep hinh, tdn ninox. Van tdc Idn nhat trong mang tuong dng vdi do sau 0,3m la 0 3 m/s Ket cau mIng ddng chly dUOc neu tren Hinh 6.1:
Hinh 6.1: Ket eau ming ddng ehiy
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KHOA HOC CONG NGHE
So 05/2020 6.2. May bOm
Dua vao dae trung ky thuat eua mang ddng chly xac dinh dugc luu Idong va edng suat may bOm, chgn may bOm XHM-7AR vdi eae thdng so ky thuat: cdng suat:
4kW, luu luong: 2.200 I/phut, dien ap: 380V, cdt ap 19m.
6.3. Thiet bj dieu khien Thiet bi dieu khien bao gdm:
- Bd dieu khien PLC Mitshubishi FX3U;
- Bien tan LS SV07IG5A: Dien ap dau vao: 3 pha 200
~ 230V, 50/60 Hz, edng suat ngd ra 7,5KV^
Cae thiet bi duae gom vao tii dien nhU Hinh 6,2:
Hinh 6.2: Tu dieu khien
Mang ddng ehay da duoc che tao hoan thien nhU anh dudi:
Hinh 6.3: Ming ddng ehiy 7. KET LUAN
Ndi dung bai bao da trinh bay dugc eie bUdc co ban de thiet ke, che tao mang ddng chly, mang ddng chly hoat ddng dung theo eac thdng sd ly thuyet. Viee che tao mIng ddng chay ciia nhdm t i c gia hoan toan sd dung vat lieu va cdng nghe cd s3n tai Viet Nam. Dieu nay the hien kha nang t y ehu ve mat cdng nghe che tao mang ddng ehiy de tao ra thiet bi thf nghiem md hinh vat Iy khdng phai mua eiia nude ngoai vdi gia thanh cao, khi n i m duge edng nghe che tao ed the ehe tao duoe mang sdng cd kich thude Idn hon nham phue vy nghien edu khoa hpe trong ITnh vye thf nghiem md hinh vat ly,
Tai lieu tham khao
[]],Https://www.essom.com/product/details/14/61.
[2],Http://www.hampden.com/product-details.
php ?viewid-929.
[3]. Http://www.gott.com.my/Gll.html.
[41. GS. TS. Lyang PhUOng Hau, PGS. TS. Tran Dinh Hai (2003), Ly thuyet thi nghiem mo hinh cong trinh thuy, NXB. Xay dUng.
[5]. Andrews Chadwick, John Morfett, Martin Borthv/ick (2013), Hydraulics in Civil and Environmental Engineering. CRC Press, London.
[6]. Subhash C. Jain (2008), Open channel flow, John Vl/iley & Sun. New York.
[7]. Ryan Waldron, MSC Thesis (2005), Physical mod- eling of flow and sediment transport using destorded scale modeling,Ju]an University.
Ngdy nhdn bai: 24/0172020 Ngay chap nhSn dang: 14/02/2020 NgUol phSn bidn:TS. U T h i HUtfng Giang
TS. Nguyen Thj Diem Chi
