528 Tuyin ttip cdng trinh Hdi nghi Cff hoc todn qudc Ky niem 30 mini Vien Cff hge vd 30 nam Tgp chi Cff hoc Hd Ndi, ngdy 8-9/4/2009 Xac dinh cac thong so hinh hoc toi uu cho buong tao
Trang 1528
Tuyin ttip cdng trinh Hdi nghi Cff hoc todn qudc
Ky niem 30 mini Vien Cff hge vd 30 nam Tgp chi Cff hoc
Hd Ndi, ngdy 8-9/4/2009
Xac dinh cac thong so hinh hoc toi uu cho buong tao ap
cua goi do' thuy tmh may nghien xi mang
Nguyen Quan Thang, Nguyen The Minh
Bp tu linh Cdng binh
Do Qudc Quang, Cao Van Mo
Trung tdm Ca khi & Tu dpng hda, Vien Cdng Nghi, Bd Cdng Thuong
Tom tat: Bdi bdo trinh bdy nhitng kit qud budc ddu nghien cieu ly thuyet trong qud trinh thuc hiin di tdi 'Nghien ciru tinh todn, thiit ki vd cdng nghi chi tgo goi da thiiy luc chiu tdi ndng din 80 tdn'' Kit qud nghien ciru da di xudt phuang phdp tinh cdc hi sd khdng thic nguyen eho goi da thiiy tTnh cd bien phuc tgp, ddng thdi sic dung thuat todn tdi uu (DE) trin ca sd md phdng Monte-Carlo di xdc dinh thdng so hinh hoc tdi uu cho mot segment trong goi da thiiy luc ciia mdy nghiin
Mo dau
Trong nhii'ng nam gan day, may nghien diing the he mdi da dugc iing dung rgng rai trong
cae nganh cong nghiep san xuat vat lieu xay dung eiing nhu mot sd nganh cdng nghiep khac can den nguyen cdng nghien Cd duge thj trudng nhu vay vi may nghien dung ed nhieu uu diem ve ket cau, hieu suat cao, ed tinh kinh te cao khi khai thac thiet bj va giam thieu d nhiem moi trudng O Viet nam, hau het cae nha may xi mang mdi duge xay dung deu su dung may nghien dirng trong nghien lieu, nghien than, nghien clinker
Trong may nghien dirng, bd phan goi da thuy lire dd ban nghien ddng vai trd het sire quan
trgng vi cum chi tiet nay chju ap lire rat Idn cua toan bd he thdng gia tai thuy lire, eiia trgng lugng phan quay may nghien, trgng lugng vat lieu trong budng nghien va cac lire nhieu dgng phat sinh trong qua trinh nghien
Nam 2005, Cdng ty TNHH Nha nude mdt thanh vien Co khi Ha ndi (HAMECO) thuc hien
de tai "Nghien ciiu thiet ke may nghien diing cho day chuyen xi mang Id quay cdng suat 2.500 tin elinker/ngay" thuge du an KHCN "Nghien eu'u thiit k l , chi tao cac thiit bj ehii yeu eho day ehuyin ddng bg san xuat xi mang Id quay cong suit 2.500 tin elinhker/ngay thay thi nhap ngoai thuc hien tien trinh ndi dja hda" Tuy nhien trong du an nay mot s i chi tiet quan trgng trong do
ed hop giam tdc tfch hgp goi dd thuy lire vin dugc nhap ngoai khdng nam trong noi dung nghien ciru
Nam 2006, Vien Cdng nghe da thuc hien de tai cip Bd ma sd 20.06/RD-2006 "Nang cao chat lugng mam nghien nham can bang ap lire lam viec eua may nghien diing" Ket qua ciia de tai da xay dung duge gia thi nghiem gdi do thiiy tTnh va thir nghiem do dac md phdng cac dieu kien eiia gdi dd thuy lire may nghien dung
Trang 2Xdc dinh cdc thdng sd hinh hoc tdi tni cho buong tgo dp 529
cua gdi dd thiiy tTnh mdy nghiin xi mdng
Trong ke hoaeh nghien cuu khoa bgc cip Nha Nude 2009-2010 da cho md dl tai ''Nghien
cini tinh todn, thiit ki vd cdng nghi chi tgo gdi do thiiy lire chiu tdi ndng din 80 tdn" Ndi dung
bai bao nay se trinh bay mdt sd ket qua nghien cuu ly thuylt budc diu eiia de tai ddi vdi gdi dd
thuy tTnh loai thudng duge tich hgp vdi hop giam toe dimg eho may nghiin dirng
Mgi gdi dd thiiy tTnh deu lam viec theo nguyen tae cap ddng dau bdi tron cd ap lien tuc vao
giua hai be mat chuyen ddng tuong ddi Chit lugng lam viec ciia loai gdi dd nhu vay phu thude
chii yeu vao do tin cay khi boat dgng cua he thong cip diu bdi tron Khi tiln hanh thiet ke
thudng dua vao ba dai lugng khdng thir nguyen la a t - He sd tai trgng, qf- He so luu lugng va
Hf- He sd cdng suat de chgn lira cae kich thude hinh hge hgp ly sao cho cdng suat day dau qua
khe hep cd gia trj eirc tieu Gia trj ciia nhung dai lugng nay khdng phu thude vao kich thude
tuyet doi ciia goi ma ehi phu thude ty le giiia chiing Chinh xac ban la ty sd dien tich ciia budng
tao ap vdi tdng dien tich ciia gdi dd Do vay viec xac dinh cac he sd khdng thu nguyen cho mot
dang hinh hge cu the ciia gdi dd thiiy tTnh ed y nghTa bet sue quan trgng
He sd tai trgng ciia gdi dd thuy tTnh aidirgc xac djnh bang bieu thiic:
W
aj=- ; (1)
W - Kha nang chju tai thuc ciia gdi (KG)
Ap - Toan bd dien tich hinh chieu ciia be mat tua (cm')
Pr - Ap lire trong budng cua gdi dd khi cd khe hd (KG/em")
He sd luu lugng eiia gdi dd:
O.A„.u
Q - Luu lugng dau (eiV/sec)
W Tai trgng tac dung len gdi dd (KG)
h - Chieu day mang dau bdi tron (em)
p - Do nhdt tuyet ddi eua dau bdi tron (KG.see/cm )
Cdng suit cin thiit eua bom d l diy diu qua khe hep trong gdi do, tfnh bing tich giua ap
lire trong budng va luu lugng qua d
W ^ h^
H,-pM = H,.{-j-f.-; (3a)
d day Hj la he so cdng suit:
/ / ^ = — ; (3)
Trang 3530 Nguyin Quan Thdng, Nguyin The Minh, Dd Qudc Quang, Cao Vdn Md
Trong nhilu tai lieu da gidi thieu cdng thiic xac djnh cac he sd khdng thii' nguyen (af, q^ Hf)
eho gli dd trdn budng trdn trung tam, gdi dd trdn budng vanh khan, gdi dd ehii' nhat buong chir
nhat, hinh con, hinh ciu Nhung chua cd tai lieu nao trinh bay dii chi tiet co sd tfnh toan cho
segment (gulc dd) phang ed hinh dang kliae Chu yeu cac sd lieu dimg cho thiet ke cac d dd thiiy
tTnh CO dang hinh hge khac deu dua tren nhung ket qua thi nghiem Tren ca sd cac bieu thiic giai
tfch CO ban da bilt va cdng cu tmh toan moi cd the xay dimg dugc phuong phap dii tin cay xac
djnh ba he si kliong thiJ nguyen quan trgng ciia gdi do nhieu segment dang quat khi cip diu vao
budng trung tam, tham chf ca goi dd cd hinh dang phuc tap hon
L M o t so tinh t o a n thiiy luc cho d o n g d a u co a p c h a y q u a k h e h e p [3,4]
Klie hep phang song song la dang duy nhat cua eae gdi dd thuy tTnh Ddng dau ed ap dugc
cap vao buong ciia gdi dd, khi ap lire Idn ban ap lire tach hai be mat, ddng dau bdi tron se
chu)'en dgng tir tam budng ra ngoai bien Trong nhCrng trudng hgp nay do kfch thude ciia khe
hep rat nho nen ddng chay tir tam ra bien dugc coi la ddng chay tang Mat kliac do cac gdi da
thuy tTnh khi boat ddng, tdc do chuyen ddng tuong ddi giiia phan tTnh va phan dgng nhd nen
trong nhieu tfnh toan cho phep bd qua anh hudng cua tdc do nay den cac thdng sd thuy luc ciia
gdi Tren ca sd ly thuyet tfnh toan cac thdng sd thuy lire cho ddng dau ed ap chuyen dgng qua
khe hep theo phuong hudng kfnh ta cd:
Phuong trinh chuyen dgng va tdc do ddng chay [2, tr293]
U = ±-±.(^y.h-/)- (4)
2.// dr
Tdc do dat gia trj cue dai khi y = hll cd nghTa la:
1 dp h~ h^ 1 dp 2 fc^
z.p dr 2 4 8/J dr
Tdc do trung binh ciia ddng chay tang trong khe hep:
2 \ 2 dp ,.-
^ = ~"n,ax= « - ^ ; (o)
3 """^ 12/^ dr
Phdn bd dp luc
dp _ \2/j dq
dr h^ r.dcp'
(7)
U^y:dpJ-^^; (8)
h'.dip r
Tir cong thiie (8) ta ed thi nhan xet ring: dgc phuang hudng kinh theo ehilu ddng chay, ap
lire dau giam dan theo ham logarit
Luu lugng ddng diu
Trang 4Xdc dinh cdc thdng sd hinh hoc tdi ini cho budng tgo dp
cita gdi dd thiiy tTnh mdy nghiin xi mdng
va dQ = h^.dcp Ap
12//
In
531
(9)
Neu tfnh eho toan bd ehu vi ta cd tdng luu lugng:
7r.h'
Q =
Cdng thirc (10) ehi dung khi tren toan bd chu vi r„ va rb la hang sd
2 Xay dung phucng phap tinh cac he so cho goi d& thiiy tinh tru'ong hop tong quat
2.1 Xdc dinh khd ndng chiu tdi thuc cua goi dd thiiy tinh
Til' cac cdng thiic (1), (2) ta thay rang de xac djnh duge cac he sd ciia gdi dd thiiy tTnh can xac djnh dugc kha nang chiu tai va luu lugng dau qua goi dd khi gdi lam viec dn dinh
Bieu do phan bd ap lire dau ed dang nhu
hinh ve Trong vimg budng dau ap luc khdng ddi
bang Pr, trong khoang tii' I'b den r,, ap luc thay ddi
theo quy luat logarit Klia nang chju tai ciia gdi
trong trudng hgp chung tfnh theo cdng thirc:
W^W,,+ jPrdF • (11) ^ a
Fn
W,=F,.p/,
Hinh 1 Phan bd ap luc trong gdi dd thiiy tinh Neu chia vimg ngoai buong tao ap thanh n phan vd ciing nhd thi bieu thuc (11) cd the viet lai nhu sau:
w = Pr-F.+J^Prf,;
1=1
d day: pr - Ap luc dau trong buong KG/cm
Fb - Dien tfch ciia budng tao ap, cm"
F„ - Phin dien tfch ngoai budng
n - Sd phin dien tfch ngoai budng dugc chia nhd
fi - Dien tfch ciia phan thir i, cm^
Pi - Ap luc tai trgng tam eua phan dien tfch thii i, KG/cm^
(12)
Trang 5532 Nguyen Qudn Thdng, Nguyin Thi Minh, Dd Qudc Quang, Cao Vdn Md
p,{\n{x)-\n{rj)
P,= T-^
In ^
(13)
Su dung bilu thirc (13) ta cd the xac djnh dugc ap luc tai mdt diem bat ky ngoai buong va cho phep tfnh kha nang chiu tai thuc cua gdi dd theo cdng thirc (12)
2.2 Tinh luu lugng thong qua goi dd
N I U ta chia toan bd chu vi thanh k phan, moi phan cd sd do gdc d tam la Acp, tuang irng phin chia nay cd ban kfnh buong la rbi va ban kfnh ngoai bien la r„i, thi cd the tfnh toan bg lugng diu qua gdi bang each sir dung cong thirc (10) dugc viet dudi dang mdi:
12// tr
Aip,
r
(14)
2.3 Xdc dinh cdc he so khong thir nguyen cua goi thuy tinh
He so chju tai:
Bang each ket hgp cdng thirc (1) va (12), ta eo bieu thirc xac djnh he sd af:
1
^/ =
Ap lire dau ngoai budng tai diem bat ky p: xac djnh theo bieu thirc (13)
- He sd luu lugng:
Ket hgp bieu thiic (2) vdi (1) ta cd:
Q.A,,p Q.A,,p
^f
1f =
W.h' aj A^,.p^.h''
Thay gia trj Q til' (14) vao (16) va gian udc ta duge bieu thiie tinh q^
1 ^^ A^,,
\2.a / '=1
•s-In
i ^
n
(15)
(16)
(17)
- He sd cdng suat: Sau khi da cd hai he so af va qrthi Hfdugc tinh theo (3)
Nhu vay khi bilt dang hinh hge cua budng, dang hinh hge eiia bien vdi ddng dau chay ra bien theo chieu hudng kfnh ta co thi cai dat chuong trinh tinh cae he sd vdi do chfnh xac cho phep
Tren co sd cac bilu thirc (15), (17) va (3) chiing tdi da tiln hanh lap trinh va tfnh toan nhim khang djnli su dung dan ciia cac suy luan toan hge va do tin cay eua ciia phuong phap tinh bang sd
Trang 6Xdc dinh cdc thdng sd hinh hoc tdi mi cho budng tgo dp
ciia gdi do thuy tTnh mdy nghiin xi mdng
533
Hv tu titiCiiini;
'- -• , ',,,,/
, • • - , /
/ /
X '• J,:,-*-'i-«'' -4
Hinh 2 So dd tinh gdi va
budng trdn
Hinh 3 Dd thj eiia he so tai trgng va he sd km lugng
klii thay ddi ty sd rb/r„
Da tien hanli ti'nli toan cho gdi dd dang bien trdn vdi budng tao ap trdn chinh tain Kit qua triing vdi ket qua tfnh bang giai tfch da dugc cdng bd [1]
Ty sd kfch thude tdi uu ddi vdi gdi dd dang nay la rb/r,, =0,55 Cac he so tuong ung af = 0,584; qf= 1,501; Hf= 2,57
Vdi gdi vudng budng vudng, cd nhieu dang cdng tliuc giai tfch kliac nhau nhung khdng cho ket qua diing vdi sd lieu thuc nghiem Theo each tfnli eiia chung tdi, khi ty s i a/b = 0,5 ta cd af = 0,5400 diing vdi sd lieu thuc nghiem (ar= 0,54) [1]
3 Tinh cho mot segment cua goi d a may nghien
Do kfch thude eua eae mam dd may nghien Idn nen nd thudng duge eau tao nhu hinh ve Toan bd be mat ciia vimg tao mang dau bdi tron dugc chia thanh tiing mang nhd rdi nhau -segment Mdi mdt segment duge cap dau dgc lap va nhu the co the tinh toan rieng Kha nang mang tai, tdng luu lugng, tdng cdng suat day dau ciia toan bd gdi dd bang tdng cua tat ca cac segment Budng tao ap tren tiing segment cua gdi dd thiiy tTnh thudng ed hai dang la budng trdn (niia tren hinh 4) va budng ddng dang vdi bien ngoai (nira dudi hinh 4)
Hinh 4 So do bd tri cac segment
tren goi dd may nghien Hinh 5 So d l tinh cho hai loai segment
Trang 7534 Nguyin Qudn Thdng, Nguyin Thi Minh, Dd Qudc Quang, Cao Vdn Md
Klii tfnh toan cac he so af, qf va Hf bing cac cdng thirc (15), (13), (17) va (3) dilu cin phai chii y la phuong trinh cua cac dudng bien gidi han cua segment cung nhu buong tao ap phai dugc vilt trong he tga do co glc tai diem 02 Dong thdi xac djnh dung gdc gidi ban Phil, Phi2, Phi3 Vf du vdi segment ed buong tao ap hinh trdn khi gdc tinh toan thay ddi tir 0-^180° thi gia trj cua r„i se bj gidi ban bdi cung A-Al, dudng thing Al-Bl va cudi ciing la cung Bl-B (hinh 5) trong khi rbi la khong ddi Trudng hgp ciia segment vdi budng tao ap ddng dang vdi bien ngoai thi rbi cQng' se thay ddi lien tuc tuong tu nhu bien ngoai
Tren co sd cac cdng thirc da biet va nhung ehii y neu tren chirng tdi da tien hanh lap trinh
dl tfnh eho segment vdi hai loai buong khac nhau Ket qua tinh toan cho segment vdi buing tao
ap hinh tron eho tren hinh 6 Gia trj cue tieu dat duge trong trudng hgp nay trong khoang Rb/Rsh = 0.58+0.65
1.0
08
06
04
0,2
0,0
C
Do thj ll? so tiii trong af
y
/
X
• /
.0
_ ,_
0,1 0,2 0,3 0,4 0,6 0,7 0,8
Rb/Rgh^
-, _,
0,9 1, )
- 1
Ciic he so qfvA Hf 10,0
9,0 8,0 7,0 6.0 5.0 4,0 3,0 2,0 1.0 -0.0
r v ; , ', "->• - ,., •, , J
i : / , ,/ :-,-^v;./;, • ; , ^|
^ - • • , : • \ \
V y \
; ' • ' • - ^ ^ ,., • ^ , ^ j
; ; , - ' ; ;;: , '['-y- '"•rC ' il_-:——-^/.^f
C : > C 3 0 0 0 0 0 0 0 0
Rb/Rgh
Hinh 6 Dd thj bieu dien gia trj cac he so af, qf va Hf eiia segment vdi budng trdn
phu thude vao ty sd Rb/Rgh
(Rb- Bdn kinh budng tgo dp; Rgh- Khodng cdch tie tdm budng din diedng thdng Al-Bl)
4 Bai toan chon thong so hinh hoc t6i uu cho g6i dS thuy tinh dam bao cong suat day dau qua khe la eye tieu
4.1 Xdy dung bai todn
Cong suat eiia he thdng cip diu eho mdt gdi dd thuy tTnh bao gdm nhieu thanh phan trong
do cd cdng suat diy dau qua khe hep giua hai mat eo chuyin dgng tuong ddi va duge xac djnh bing tich giira ap luc trong buong tao ap va luu lugng diu (3a) Tir bilu thiic (3a) eho thiy, co the giam thanh phin cdng suit nay bing each giam gia trj cua he so cdng suit Hf Do vay, trong qua trinh thiit kl gdi dd thiiy tTnh ngudi ta ludn mong mudn vdi kfch thude da cho eua goi dd (hoac mdt segment) cin tim kfch thude hinh hge ciia budng sao eho Hf dat gia trj cue tilu
Trang 8Xdc dinh cdc thdng sd hinh hoc tdi leu cho budng tgo dp ^^^
cita gdi da thiiy tTnh mdy nghiin xi mdng
Tir nhung vi du tfnh toan d tren ed thi rut ra nhan xet ring: Khi hinh dang ngoai eiia gdi
hoac mdt segment la cd dinh thi gia trj ciia eae he s6 af, qf va Hf ehi eon phii thuge vao kich
thude hinh hge ciia budng tao ap Vdi goi dd cd buong tao ap tron thi af, qf va Hf ehi phu thude
vao ban kfnh budng tao ap Rb (ham mot bien) Bing phuang phap sd viec xac djnh gia trj eiia Rb
de Hf dat gia trj cue tieu la don gian nhu trinh bay d tren va cac dd thj Nhung vdi budng tao ap
CO bien phiic tap ban vi du nhu trong trudng hgp segment co budng dong dang vdi bien thi
khong dan gian Vdi trudng hgp eu the nhu tren hinh 5 thi Hf se phu thuge vao ba biin co ban:
Hr = f{r,„r,„„(p„); (18)
d day: ^b - Ban kinh trong eua budng tao ap;
rnb - Ban kfnh ngoai ciia budng tao ap;
cpb - Nira gdc d tam (gdc quat) ciia budng tao ap
Ham/(^r,6, r,,/,, (pi,) khd ed the bieu dien bang bieu thiic giai tfch tudng minh, bdi de tinh
duge Hf phai thdng qua rat nhieu cac tfnh toan trung gian nhu da trinh bay d tren Nhung eo the
khang djnh rang vdi mdi tap cac gia trj ciia (r,b, r„b, cpb) ta cd the xac dinh dugc mdt gia trj duy
nhat eua Hf Viec xay dung hkmf(r,t„ r,,;,, tph) tudng minh eiing khdng thuc su can thiet khi cac
thuat toan tdi uu mdi cho phep giai bai toan chi can gia trj eiia ham Trong he tga do vdi gdc la
diem 0 2 nhu tren hinh 5, bai toan tdi uu co dang:
Tim tap cac gia trj (r,h, r,,/,, cpb) sao cho ham:
Hf = f{r,„r„„q),)-^Min;
vdi cac dieu kien rang budc sau:
0 > r , b > r , (19)
0 < rnb < fn
0 < cpb < cps
d day: r, - Ban kinh trong ciia segment;
r„- Ban kfnh ngoai eiia segment;
(Pb - Nu'a gdc d tam eua segment
Nhirng dilu kien rang budc tren chi dam bao budng tao ap khdng vugt ra ngoai gidi ban
hinh hoc cho phep
4.2 Chgn phuang phdp gidi
D I giai bai todn (19) ed mdt sd phuong phap sau:
- Phuong phap bien hinh hoac phuong phap dung sai mem [6]
Thuat toan gen (Genetic Algolrithm - GA) [7]
Thuat toan md phdng luyen kim (Simulated Annealing - SA) [8]
Thuat toan tiln hda vi phan (Differential Evolution - DE) [9], [10]
Trang 9536 Nguyen Qudn Thdng, Nguyin Thi Minh, Dd Qudc Quang, Cao Vdn Mo
Hai phuong phap diu la cac phuang phap truyin thdng, viec xir ly eae dieu kien han chi phiic tap, kit qua phu thuge vao diem xuat phat ban dau, khd dam bao cho chung ta nghiem toi
uu toan cue Ba thuat toan sau la cac thuat toan thuge lap cae thuat toan dua tren co sd mo phdng Monte - Carlo Theo kinh nghiem lap trinh va tfnh toan thir nghiem mdt sd bai toan phiic tap ciia chiing toi eho thiy, thuat toan SA va DE ludn cho ket qua diing va on dinh, tieu chuin dirng xay dung dan gian va chinh xac hon Thdi gian tfnh tren may eiia thuat toan DE luon la nhd nhit so vdi cac thuat toan khac khi giai nhiing bai toan phuc tap De giai bai toan (19) chung tdi da chgn thuat toan DE Giong nhu thu^t toan GA, DE dira tren qua trinh tiln hoa vdi
ba toan tii' ca ban la dot bien, lai ghep va lira chgn nhung ban chat mdi toan tir lai khac hin vdi thuat toan GA Doan chuo'iig trinh sau md ta nhirng budc co' ban nhat eiia thuat toan DE truyin thong
//Bat ddu qud trinh tim kiim // Tgo qudn thi tine nghiin ban ddu vdi Np cd thi
DO
do i=l,Np //Dpi biin vd lai ghep
do ro = floor(rand(0,l)*Np); while (ro = i);
do rj = floor(rand(0,l)*Np); while (ri= ro orrj = i);
do r2 =floor(rand(0,1) *Np); while (r2= rj or r2- ro or r2 = i);
jranj = floor(D*rand(0,1));
do j=l,D// Tgo vec to thie nghiem
if (rand(0,l) <Cr or J =jr„„ci) then Ujj = Xj^i-o + F*(xj,.i -Xjj.2); //Kiim tra diiu kiin rdng bupc ?
else
t^j.i ~ Xjj;
end if end do
// Chgn thi hi tiip theo
do / =1, Np
if (f (Ui) <f(Xi) ) Xi = Ui;
end do end do
WHILE (Cho din khi dgt tiiu chudn dieng)
Trang 10Xdc dinh cdc thdng sd hinh hoc toi ini cho budng tgo dp
ciia gdi do thiiy tTnh mdy nghiin xi mdng
Thdng thudng cd thi diing thuat toan DE khi bilu thiic sau thda man:
537
inn
fi^Mm ~~
N
<s-(20)
cd nghTa la gia trj ham eua mgi ca thi trong quin thi gin nhu bing nhau tiiy thude vao gia trj 8 (thudng chgn s = 10"'^)
4.3 Kit qud vd mpt vdi nhgn xet
Ket qua tfnh cac tham sd tdi uu theo cdng suat day diu cue tilu eho segment goi dd thiiy tTnh may nghien dirng vdi hai loai budng cho d bang 1
Bang 1 Cae tham sd tdi uu Cae tham sd
Ban kfnh trong ciia segment (em)
Ban kfnh ngoai cua segment (cm)
Nira gdc d tam ciia segment (do)
CAC THONG SO TOI LTU
Ty sd dien tfch budng cao ap vdi
dien tfch cua segment (%)
He sd tai trgng
He sd luu lugng
He sd cdng suat
Ky hieu
R
Rn 9s
Fb/Fs
af
qf
Hf
Buong cao
ap tron 41.5 66.5
10
21.7
0.507 1.463 2.887
Buong eao ap ddng dang
vdi bien 41.5 66.5
10
28.5
0.568 1.458 2.569 Tren day mdi chi la nhung ket qua budc dau eiia de tai va eung chi gidi ban nhiing tfnh toan nghien eii'u trong viing ed chuyen ddng tuong ddi giua hai be mat trugt Tuy eon mdt sd ylu td chua thi tfnh hit trong khi tinh toan, tuy vay nhdm nghien eiiu eung cd thi manh dan dua
ra mdt vai nhan xet:
Ket qua qua trinh nghien cii'u da de xuat phuang phap tfnh gan diing dua tren eo' sd vi phan dien tich cua gdi do, do chinh xac cua ket qua phu thude vao mirc do vi phan nay Diia vao phuong phap tinh nay, bing cae thuat toan tdi uu mdi ed the xac djnh nhanh bd thong sd hinh hge toi uu cua ddi tugng nghien ciru
Vdi phuong phap tfnh nhu tren, do chfnh xac ciia cae ket qua tfnh so vdi eae kit qua tfnh bing giai tfch cung nhu nhung sd lieu thuc nghiem da dugc cdng bo cd thi dimg dugc trong qua trinh tilp tuc nghien ciru d do thuy tTnh eho may nghien diing