- IPC) va ham lugng tro trung binh 17c Irong than Ngoai ra, he sd khi do đt chay
h vdi Icet qua do dgc (Microgram/m'^)
3.3. Danh gia anh hudng cua he sd khuech tan
De danh gia anh hudng ciia tham sd khuech tan hkng viee dua ra 2 each tinh Oy, Oz khac nhau, each 1 la six dung each tinh ciia Turner (1970) va Ludwig (1977)
va each 2 tinh cac tham sd khuech tan rdi theo mot sd sd lieu do dac d Viet Nam [13].
Cdch 1: Oy, â dugc tinh nhu sau:
Trudng hgp đ on dinh khdng thay đi trong qua trinh dich chuyen, md hinh su dijng cdng thiie ciia Tunner
a ^ a x ^ ^ a,b - Cac he sd phu thugc miie do on dinh ciia khi quy^n
X - Khoang each tdi ngudn (m).
Trudng hgp do on dinh thay đi trong qua trinh dich chuyen md hinh su dung cdng thiíc sau cua Ludwig:
( a J ^ = a J ( x . X 4 - 5 x h
rfa ] r''
(xJ.
Trong đ
(c>y)t-i . (c^zX-i 1^ cac gia tri tai budc thdi gian t-1.
a, la khoang each dich chuyen giua hai budc thdi gian t - 1 va t.
ay, by, â, b^ la cac hang sd thue nghiem thay đi theo Idp on dinh khi quyen.
Cdch 2: Tinh cac tham sd khuech tan rdi theo mot sd sd lieu do dac d \'iet
Nam [5].
He sd khuech tan dugc xac dinh:
Ko = Ky/U
Ky - ại - b.x'
Khu vue Ha ndi, miia đng gia tri cua a = 7,14.10^ , b= 4,61.10"^'. Trong đ:
CT^, Gý. la he sd phat tan ciia khi quyen theo chieu cao va tren mat phang
nam ngang.
KQ: Kich thudc khuech tan rdi ngang, Ky: He sd khuech tan rdi ngang (mVs). o U: Tdc do gid trung binh (m/s).
x: khoang thdi gian (x = At).
x: triing vdi chieu gid thdị
n: chi sd tang ket nhiet (khi quyen bat on dinh n = 0,14; khi quy^n on dinh n = 0,2).
Su dung 2 each tren de tinh gia tri cua Oy , â trung binh 1 gid ciia 10 gid dau tien theo puff tbii nhát ciia ngudn 1 (nha may Cao su Sao \^ang) cho ket qua nhu sau:
- Gia tri cua a,
Khoang each (m) 1685 4895 8373 13723 16933 21213 26563 27365 29505 29773
Theo so Ueu do dac 0 Viet N a m 162.1 704.7 2504.7 6103.4 3867.9 7336.5 8611.1 28374.4 11027 10603.9 Turner va Ludwig 49.9 215.3 2015.3 5614.9 3378.5 6938.9 7869.6 28025 10143.4 10115
Gia tri ci!ia Oy trong tnrdng hgp khoang each x nhd thi gia tri a,, theo sd lieu
do dac d Vi^t Nam la Idn hon gia tri Oy ciia Turner va Ludwig, khi khoang each x
cang Idn thi gia tri Gy ciia Turner va Ludwig tien tdi la bang gia tri Qy theo sd lieu
do dac d Vi^t Nam.
_ Gia tri ciia ạ
Khoang each (m) 1685 4895 8373 13723 16933 21213 26563 27365 29505 29773
Theo so lieu do dac 0 Viet N a m 81.3 352.6 52.3 52.3 70.6 62.2 55.1 92.3 67.6 78.4 . Turner va Ludwig 17.3 34.3 64.5 117.8 97.5 137 139.9 163.7 152.4 168.2
Vdi khoang each x < 5000 m thi gia tri ciia â theo sd lieu do dac d \^iet Nam
Idn hon gia tri â theo cdng thue cua Turner va Ludwig, vdi x > 5000 m thi gia tri a,
theo sd lieu do dac d Viet Nam nhd hon gia tri â cua Turner va Ludwig.
5000 10000 15000 x(m) x(m)
20000 25000 iOOOO
Theo sd lieu do dac 6 Viel Nam Tumer va Ludwio
Hinli 3.6. So sdnh gid tri ciia S,.
5000 10000 15000 20000 25000 30000 x ( m ) x ( m )
Theo sd lieu do dac d Viet Nam —•— Turner va Ludwig
./////// 3.7. So sdnh gid tri ciia d-
Ap dung cac gia tri a,., a, trong each 2 vao viee tinh ndng do trung binh 1 gid irong miia Ddng ciia vung Ha Ngi vdi vice sir dung 8 ngudn diem va 1 ngudn dien irons Bans 3.4 va Bang 3.5, ket qua dugc trinh bay tren Hinh 3.8 va Hinh 3.9.
/ X > i J C c S J