TN Qu trnh v Thit bThi gian luMC LC

I. TRCH YU21.Mc ch th nghim22.Kt qu th nghim2II. L THUYT TH NGHIM21.Cc khi nim c bn22.Cc phng php nghin cu thi gian lu43.Hm phn b thi gian lu ca m hnh dy hp6III. THIT B TH NGHIM8IV. PHNG PHP TH NGHIM8V. KT QU TH NGHIM8VI. BN LUN13VII. PH LC151.Cc gi tr tnh ton cho h 1 bnh152.Cc gi tr tnh ton cho h 2 bnh163.Cc gi tr tnh ton cho h 3 bnh17VIII. TI LIU THAM KHO17

I. TRCH YU1. Mc ch th nghim Kho st thi gian lu ca h thng bnh khuy trn mc ni tip m hnh dy hp. Xc nh hm phn b thi gian lu thc v so snh vi hm phn b thi gian lu l thuyt.2. Kt qu th nghim hp thu cc i (cho 1 bnh): ng knh bnh khuy: Chiu cao mc nc trong bnh: Lu lng nc chy vo bnh:Bng 1: Kt qu thHMtBnh

12345678910

0,0020,0050,0060,0090,0010,0010,0010,0010,0000,000

1112131415

0,0000,0000,0000,0000,000

HHaiBnh

12345678910

0,0000,0000,0010,0020,0010,0030,0030,000,0040,005

11121314151617181920

0,0040,0040,0040,0040,0030,0020,0030,0020,0040,002

2122232425

0,0010,0010,0000,0000,000

HBaBnh

12345678910

0,0000,0010,0010,0020,0020,0020,0030,0030,0020,003

11121314151617181920

0,0030,0030,0020,0010,0020,0040,0030,0020,0010,001

21222324252627282930

0,0010,0030,0020,0010,0020,0000,0010,0020,0010,001

3132333435

0,0000,0000,0000,0000,000

II. L THUYT TH NGHIM1. Cc khi nim c bn Trong h thng thit b, nhng phn t lu cht khc nhau s i theo nhng con ng khc nhau. Da trn hm phn b thi gian lu xc nh c, ta c th nh gi tng quan v dng trong thit b, cc nhc im sinh ra khi thit k nh vng t, dng chy tt... v tm cch khc phc nh nh gi ny. Nghin cu thi gian lu l phng php cn thit so snh thit b da trn dng vt liu t c th ci tin, lp m hnh ti u. Cng da trn hm phn b thi gian lu ta c th vn hnh ti u v qua thit lp c cc thng s, phng php iu khin cng nh ti u ha qu trnh trong thit b. Thi gian lu ca mt phn t trong h l thi gian phn t lu li trong bnh phn ng, hay trong thit b bt k cn kho st. Thi gian lu ca ca mt thit b l mt i lng xc sut. Nh vy tt c thi gian lu u dao ng xung quanh thi gian lu trung bnh, do xc nh thi gian lu trung bnh c bit c ngha.

(1)

Trong l thi gian lu ca phn t bt k i. Vi nh ngha hm phn b thi gian lu , ta c:

Hay Vi cc hm im, ta c:

K l cc khong chia bng nhau Thi gian lu trong bnh th tch:

Vi: th tch lu cht trong bnh, lt.

lu lng ca dng vo thit b, lt/giy. Nu cht ch th khng t tng quan l tng th phng trnh trn khng tho mn (nu c th cht ch th b hp ph vo thnh bnh hoc cc chi tit hp ph).2. Cc phng php nghin cu thi gian lu Nghin cu thi gian lu c th tin hnh theo cc phng php:1) Xc nh thnh phn ca cc cu t thi im t (hoc ) ra khi thit b, xc nh hm F(t) hoc F().2) Xc nh thnh phn ca cc cu t thi im t (hoc ) vn cn lu li trong thit b, hm I(t) hoc I().3) Xc nh thnh phn ca cc cu t thi im t (hoc ) ang trong qu trnh that ra khi thit b, hm f(t) hoc f(). kho st kh nng hot ng ca mt thit phn ng thc t ta thng dng phng php kch thch p ng (phng php nh du). Cc dng kch thch u vo v p ng u ra c trnh by trn hnh 1

Tn hiu vo Tn hiu ra (Kch thch) Bnh (p ng)

Tn hiu vo bt kNng cht ch th

Ra

Thi gianTn hiu vo tun honNng cht ch th

Ra

Thi gian

Tn hiu bcNng cht ch th

Ra

Thi gian Tn hiu xungNng cht ch th

Ra

Thi gian

Hnh 1: Cc dng tn hiu thng dng Nh vy cc phn t nh du phi c c im l khng c nh hng v khc bit vi cc phn t to nn tng quan trong h. Cc loi cht ch th i vi mi trng lng c th l dung dch mu, cc cht phng x, cc ng v phng x n nh, cc ht rn pht sng... Cc cht ch th thch hp vi tnh cht ca cc phn t trong h phi c khi lng ring, nht, h s khuch tn thch hp. Khi c cc ch th thch hp, ta c th n vo h theo hai kiu tn hiu l: tn hiu ngu nhin (Stochas) v tn hiu xc nh (Determinis). Loi tn hiu xc nh c th chia lm hai loi l tn hiu tun hon v tn hiu khng tun hon. kho st cc thit b, ngi ta s dng tn hiu xc nh khng tun hon. Loi tn hiu ny c th to ra nh:1) nh du bng va chm.2) nh du bng cho nhp vo lin tc mt lng xc nh.3) nh du bng cho nhp chim ch ton b trong h. V tin li trong s dng v s ng dng ca tn hiu kch thch c dng bc hoc dng xung. Trong th ngim, ta s dng loi nh du bng va chm. Loi nh du ny chnh l s thc hin iu kin k thut hm Dirac (hm ng lng Dirac), hay cn gi l hm Delta.

Loi nh du ny thng thch hp vi cht mu3. Hm phn b thi gian lu ca m hnh dy hp a s cc thit b thc li thng c hm phn b l ca m hnh dy hp. Trong mt bnh phn ng c coi l l tng vi kiu nh du va chm phi tha mn: th tch VR trong bnh l hng s theo thi gian, trong bnh c s khuy trn hon ton mt thnh phn trong h mt cch ng nht mi v tr thuc th tch VR. Nh vy, trong bnh c s t bin ca dng vo. Thi gian lu trung bnh th tch:

Khi ni cc bnh l tng li, ta c m hnh dy hp Hm phn b c dng tng qut

Khi , ta c m hnh khuy trn l tng. Con khi , ta li c m hnh y l tng. Gi s ban u khng c cht ch th trong dng lu cht vo bnh, sau tc ng tn hiu xung vo bng cc cho mt lng cht ch th nht nh vo dng lu cht trong khong thi gian rt ngn. ng cong biu din nng theo thi gian thu gn ca cht ch th trong dng ra ng vi tn hiu kch thch dng xung ti u vo gi l ng cong C. Nng ban u ca cht ch th l Co. Vi din tch bn di ng cong bng 1, ta c: Thi gian thu gn v th nguyn: Vi t l thi gian phn t lu cht bt k i qua thit b.

v c xc nh theo (1)

(2)

Hay(3)

Hnh 2: ng cong C biu din p ng ti dng ra cho tn hiu xung ti u vo

III. THIT B TH NGHIM ng nghim Th k Pipet Phm mu My o truyn sut (hp th) nh sng.

IV. PHNG PHP TH NGHIMTin hnh theo trnh t sau M van cho nc ln thng cao v cho n khi c nc trong ng chy trn. M kha cho nc chy qua lu lng k vo h thng bnh khuy v chnh lu lng dng chy. H mt bnh: khi h thng n nh, cho phm mu vo bnh 1. Bm th k (ng thi vi thi gian cho mu vo thit b), ly gc thi gian. Dng ng nghim ly mu theo thi gian, sau em mu i so mu. H hai, ba bnh: lm ging nh h mt bnh, cho phm mu vo bnh 1 v ly mu bnh cui cng (t ng thng nhau cui cng).

V. KT QU TH NGHIMBng 2: S liu tnh ton cho H 1 bnht (pht)DThc tL thuyt

ti.DiEE

10,0020,0020,2670,2000,3250,7227

20,0050,0100,5350,5000,6500,5222

30,0060,0180,8020,6000,9740,3774

40,0090,0361,0690,9001,2990,2727

50,0010,0051,3370,1001,6240,1971

60,0010,0061,6040,1001,9490,1424

70,0010,0071,8710,1002,2740,1029

80,0010,0082,1390,1002,5980,0744

90,0010,0092,4060,1002,9230,0538

100,0000,0002,6730,0003,2480,0388

110,0000,0002,9410,0003,5730,0281

120,0000,0003,2080,0003,8980,0203

130,0000,0003,4750,0004,2220,0147

140,0000,0003,7430,0004,5470,0106

150,0000,0004,0100,0004,8720,0077

Cc s liu cn cho tnh ton

(pht)

(m3/pht)

(m3)

(pht)

Hnh 3: th biu din mi quan h cho trng hp l thuyt v thc nghim h 1 bnh

Bng 3: S liu tnh ton cho H 2 bnht (pht)DThc tL thuyt

ti.DiEE

10,0000,0000,0800,0000,1620,4695

20,0000,0000,1600,0000,3250,6785

30,0010,0030,2400,2000,4870,7355

40,0020,0080,3200,4000,6500,7087

50,0010,0050,4000,2000,8120,6402

60,0030,0180,4800,6000,9740,5552

70,0030,0210,5600,6001,1370,4681

80,0020,0160,6400,4001,2990,3866

90,0040,0360,7200,8001,4620,3143

100,0050,0500,8001,0001,6240,2524

110,0040,0440,8800,8001,7860,2006

120,0040,0480,9600,8001,9490,1582

130,0040,0521,0400,8002,1110,1238

140,0040,0561,1200,8002,2740,0964

150,0030,0451,2000,6002,4360,0746

160,0020,0321,2800,4002,5980,0575

170,0030,0511,3600,6002,7610,0442

180,0020,0361,4400,4002,9230,0338

190,0040,0761,5200,8003,0860,0258

200,0030,0601,6000,6003,2480,0196

210,0010,0211,6800,2003,4100,0149

220,0010,0221,7600,2003,5730,0113

230,0000,0001,8400,0003,7350,0085

240,0000,0001,9200,0003,8980,0064

250,0000,0002,0000,0004,0600,0048

Cc s liu cn cho tnh ton

(pht)

(m3/pht)

(m3)

(pht)

Hnh 4: th biu din mi quan h cho trng hp l thuyt v thc nghim h 2 bnh

Bng 4: S liu tnh ton cho h 3 bnht (pht)DThc tL thuyt

ti.DiEE

10,0000,0000,0680,0000,1080,114

20,0010,0020,1360,3000,2170,331

30,0010,0030,2050,3000,3250,538

40,0020,0080,2730,6000,4330,691

50,0020,0100,3410,6000,5410,780

60,0020,0120,4090,6000,6500,811

70,0030,0210,4780,9000,7580,798

80,0030,0240,5460,9000,8660,753

90,0020,0180,6140,6000,9740,689

100,0030,0300,6820,9001,0830,615

110,0030,0330,7510,9001,1910,538

120,0030,0360,8190,9001,2990,462

130,0020,0260,8870,6001,4070,392

140,0010,0140,9550,3001,5160,329

150,0020,0301,0240,6001,6240,273

160,0040,0641,0921,2001,7320,224

170,0030,0511,1600,9001,8410,183

180,0020,0361,2280,6001,9490,148

190,0010,0191,2970,3002,0570,119

200,0010,0201,3650,3002,1650,096

210,0010,0211,4330,3002,2740,076

220,0030,0661,5010,9002,3820,060

230,0020,0461,5690,6002,4900,048

240,0010,0241,6380,3002,5980,038

250,0020,0501,7060,6002,7070,029

260,0000,0001,7740,0002,8150,023

270,0010,0271,8420,3002,9230,018

280,0020,0561,9110,6003,0320,014

290,0010,0291,9790,3003,1400,011

300,0010,0302,0470,3003,2480,008

310,0000,0002,1150,0003,3560,006

320,0000,0002,1840,0003,4650,005

330,0000,0002,2520,0003,5730,004

340,0000,0002,3200,0003,6810,003

350,0000,0002,3880,0003,7890,002

Cc s liu cn cho tnh ton

(pht)

(m3/pht)

(m3)

(pht)

Hnh 5: th biu din mi quan h cho trng hp l thuyt v thc nghim h 3 bnhVI. BN LUNCu 1: So snh gia hm phn b thi gian lu l thuyt v thc nghim H 1 bnh: da vo th ta thy hm thi gian lu l thuyt v thc nghim khng ging nhau. a phn cc gi tr E l thuyt u ln hn so vi E thc nghim. Nhn vo cc gi tr ca th ta thy thi gian lu trong bnh trn thc t nh hn so vi tnh ton theo l thuyt nn nhiu kh nng s to ra cc vng t, cnh khuy khng tc ng ti c. H 2 bnh: da vo th ta thy hm thi gian lu l thuyt v thc nghim tng i ging nhau khi cc gi tr cng tng n mt im nht nh ri gim xung nhng tng li khng u v tng gim khng theo mt quy lut no c. Cc gi tr E thc nghim hu ht u ln hn E l thuyt. Cc gi tr thu gn u nhanh hn so vi tnh ton nn c kh nng s xut hin cc vng t trong h thng H 3 bnh: da vo th ta thy hm thi gian lu l thuyt v thc nghim khng ging nhau. Cc gi tr E thc nghim tng gim tun hon.Cu 2: Cc hin tng ca qu trnh v thit b pht sinh s mt n nh Do to nn vng t trong thit b. Nguyn nhn ca vng t l do tc ca cnh khuy qu chm nn c nhng vng khng khuy ti. Do s tun hon ca lu cht. Nguyn nhn ca s tun hon l do lu cht phn b khng u trong dung dch. iu c th l do c im ca bn thn lu cht hoc cng l do tc khuy qu chm. khc phc cc hin tng trn, ta c th tng cng tc khuy khuy u v khuy c ton b dung dch. Ngoi ta cn c cc hin tng pht sinh s mt n nh khc nh: S thay i vn tc v phng chuyn ng ca lu cht do hnh dng b mt thit b (bnh phn ng, cnh khuy, ng ng...) to thnh cc vng khng mong mun nh vng xoy, vng cht, vng chy qua..., cc vng ny c th tn ti trong mt khong thi gian ngn hay ko di lm nh hng n kt qu o. Vn tc quay ca cnh khuy khng n nh theo thi gian (do motor, trc khuy...). S hp th cht ch th ca thit b (c bit l ng ng) lm nng ca cht ch th gim theo thi gian. Nhit mi trng trong qu trnh th nghim bin i lm thay i tng quan gia cc phn t lu cht c trong h (thay i nht, t trng, vn tc...), thay i cc tnh cht ca lu cht chuyn ng trong ng ng v thit b.Cu 3: nh gi sai s h thng v sai s ngu nhina. Sai s thit b My o truyn sut ca nh sng: nguyn nhn ch yu dn n sai s bi th nghim Do cuvet cha mu o v mu kim chng khng sch. Cc cht bn bm trn n cng hp th nh sng nn nh hng n kt qu o. Do my o qu nhy nn ch cn mt cht vt bn trn cuvet nh hng rt ln n kt qu. Ty vo cch t cuvet trong my o mt quang m ta s thu c nhng kt qu khc nhau, v c cc vt bn khc nhau ti cc v tr khc nhau trn b mt cuvet. V my o cng c nn c phn sai st Do in p cung cp cho my khng c n nh lm Cnh khuy Quay khng u cc bnh, vn tc khng u do in p Quay chm lm cho khng ng u tng ln ng ng Do tr lc ca ng v van khng ging nhau, nn vic iu chnh lu lng vo v ra bng nhau mi bnh rt kh khn. S kh khn ny cng tng ln i vi h nhiu bnh. Thc t th nghim cho thy khng th gi nguyn th tch lu cht trong mi bnh so vi ban u trong sut thi gian th nghim (mc d h hot ng kh n nh trc khi cho cht ch th). Trong sut qu trnh th nghim ta phi lun iu chnh cc van sao cho th tch lu cht trong mi bnh l khng i, nn s nh hng n tnh n nh ca h thng.b. Sai s thao tc Do xc nh thi gian ly mu Do lau chi cuvet cha tht sch, cuvet cha hon ton kh khi a vo my. Do iu kin th nghim khng c dng c lm kh cuvet cng nh s lng cuvet thay th.c. Sai s do hot ng ca h thng Do c s sut hin ca vng t Do cnh khuy hot ng khng n nhd. Sai s i vi thi im ban u v dng ca tn hiu xung Ta khng th xc lp c dng thc ng ca hm ng lng DIRAC do khng th khng ch thi gian cho cht ch th bng 0 (thc t th nghim cho cht ch th bng pipet mt khong 5s), thi gian ny l kh ln v do gy nn khc bit gia ng cong thc nghim v l thuyt (c xy dng t hm ng lng DIRAC).

VII. PH LC1. Cc gi tr tnh ton cho h 1 bnh Thc t hp th cc i

Thi gian lu trung bnh Thi gian thu gn o s phn b thi gian lu L thuyt

Lu lng nc chy vo bnh (l/pht) (m3/pht)

Th tch 1 bnh khuy

Thi gian lu l thuyt(pht)

Thi gian thu gn

o s phn b thi gian lu2. Cc gi tr tnh ton cho h 2 bnh Thc t hp th cc i

Thi gian lu trung bnh Thi gian thu gn o s phn b thi gian lu L thuyt

Lu lng nc chy vo bnh (l/pht) (m3/pht)

Th tch 1 bnh khuy

Thi gian lu l thuyt(pht)

Thi gian thu gn

o s phn b thi gian lu3. Cc gi tr tnh ton cho h 3 bnh Thc t hp th cc i

Thi gian lu trung bnh Thi gian thu gn o s phn b thi gian lu L thuyt

Lu lng nc chy vo bnh (l/pht) (m3/pht)

Th tch 1 bnh khuy

Thi gian lu l thuyt(pht)

Thi gian thu gn

o s phn b thi gian lu

VIII. TI LIU THAM KHO[1]. V B Minh, Qu trnh v Thit b trong Cng Ngh Ha Hc & Thc phm Tp 4: K thut phn ng, Nh xut bn i hc Quc gia Tp.HCM, 2004, 380tr.[2]. Nguyn Th Thu Vn, Phn tch nh lng, Nh xut bn i hc Quc gia Tp.HCM, 2004, 540tr.1