1.1
DESCRIPTION
12TRANSCRIPT
MC CH TH NGHIM Xc nh ct p ton phn ca bm, cng sut, hiu sut cho bm ly tm bng vic o c cc thng s khi thay i lu lng ca bm. Kho st v xy dng cc ng c tuyn ca bm. S dng nh lut t l tin on cc thng s c trng ca bm. Kho st s nh hng ca vic thay i ct p ng ht i vi bm, ng thi kho st hin tng xm thc bng cch thay i p sut thay i p sut trong ng ht vi vic thay i van ht thay i lu lng. Xy dng ng c tuyn ca mng ng xc nh im lm vic ca bm.THC NGHIMKt qu th nghim Th nghim 1: Ch tc bm 70%STTLu lng Q (l/s)Tc bm n (rpm)p sut ht Ph ( kPa)p sut yPd (kPa)Nhit T (oC)Moment xon ng c t (N.n)
10.001050.002.3037.5035.400.45
20.191050.002.1035.7035.300.49
30.291050.001.9033.0035.10.50
40.461050.001.1030.4035.100.52
50.581050.000.4027.7035.400.53
60.651050.00-0.4025.0034.900.53
70.721050.00-1.1021.9034.900.55
80.821050.00-1.8018.2035.300.57
90.901050.00-2.6014.9035.100.57
100.941050.00-3.1012.6035.100.58
Ngy th nghim:Xc nhn:
Th nghim 2:STTLu lng Q (l/s)Tc bm n (rpm)p sut ht Ph (kPa)p sut y Pd(kPa)Nhit T (oC)Moment xon ng c t (N.m)
Kt qu kho st ch 50%
10.00750.002.5021.4035.200.45
20.09750.002.2019.4035.100.46
30.28750.001.9017.7035.500.46
40.37750.001.5016.0035.000.47
50.41750.001.3015.5035.600.48
60.46750.000.9014.0035.300.49
70.53750.000.4012.4035.000.49
80.58750.000.2011.0035.400.50
90.61750.00-0.309.1036.000.51
100.66750.00-0.508.2035.600.51
Kt qu kho st ch 60%
10.00900.002.4026.1035.400.46
20.21900.001.7024.4035.100.47
30.35900.001.6023.6035.000.48
40.43900.001.1021.5035.500.49
50.48900.000.7019.8035.600.49
60.56900.000.4019.0035.800.50
70.61900.000.2017.0035.500.50
80.64900.00-0.5015.3035.400.52
90.78900.00-1.6010.7035.300.52
100.81900.00-1.809.4035.500.53
STTLu lng Q (l/s)Tc bm n (rpm)p sut ht Ph (kPa)p sut y Pd(kPa)Nhit T (oC)Moment xon ng c t (N.m)
Kt qu kho st ch 80%
10.001200.002.5045.9035.100.48
20.171200.001.9043.1035.400.51
30.301200.001.7042.0035.500.52
40.351200.001.4040.7035.400.54
50.501200.000.6037.0035.300.56
60.561200.000.3035.7035.300.57
70.761200.00-1.5028.4035.100.59
80.851200.00-2.2024.6035.400.61
91.011200.00-4.1016.1035.100.62
101.101200.00-5.0013.6035.300.64
Kt qu kho st ch 90%
10.001350.002.1055.9034.700.54
20.201350.002.0052.3034.100.58
30.481350.000.5049.2034.500.60
40.541350.000.5047.6034.700.61
50.681350.00-0.3043.1034.600.63
60.741350.00-1.4039.1034.600.66
70.881350.00-2.8035.0034.300.68
80.981350.00-3.8029.0034.800.69
91.091350.00-4.7024.0034.600.71
101.201350.00-6.3016.6034.200.76
STTLu lng Q (l/s)Tc bm n (rpm)p sut ht Ph (kPa)p sut y Pd(kPa)Nhit T (oC)Moment xon ng c t (N.m)
Kt qu kho st ch 100%
10.001500.002.1066.4035.700.47
20.211500.001.5061.7034.900.55
30.481500.000.6056.1034.900.56
40.601500.000.2053.5034.800.64
50.661500.00-0.7052.5035.100.66
60.811500.00-2.1046.7035.100.66
70.881500.00-3.0043.1035.100.69
80.941500.00-3.6039.2034.900.70
90.981500.00-3.9038.1035.000.70
101.301500.00-8.8016.4035.000.77
Ngy th ngim:Xc nhn:
Th nghim 4STTLu lng Q (l/s)Tc bm n (rpm)p sut ht Ph (kPa)p sut y Pd(kPa)Nhit T (oC)Moment xon ng c t (N.m)
Kt qu kho st ch 20%
10.24300.001.601.4035.100.52
20.23300.001.301.5034.600.52
30.21300.001.201.2035.100.52
40.19300.000.701.1034.800.52
50.16300.000.401.0035.000.52
60.13300.000.300.9035.100.52
70.11300.000.201.0034.900.52
80.09300.00-0.100.7034.800.52
90.07300.00-0.200.8035.000.52
100.00300.00-0.600.5034.600.52
Kt qu kho st ch 60%
10.81900.00-2.207.3035.100.53
20.76900.00-5.606.2034.600.51
30.68900.00-9.404.8035.100.51
40.57900.00-13.004.7034.800.49
50.52900.00-16.504.2035.000.49
60.49900.00-17.702.4035.100.48
70.30900.00-21.101.3034.900.48
80.21900.00-21.301.0034.800.46
90.04900.00-22.001.2035.000.43
100.00900.00-24.201.0034.600.45
STTLu lng Q (l/s)Tc bm n (rpm)p sut ht Ph (kPa)p sut y Pd(kPa)Nhit T (oC)Moment xon ng c t (N.m)
Kt qu kho st ch 100%
11.281500.00-9.1015.2035.900.75
21.251500.00-16.2016.1035.800.74
31.091500.00-26.1010.6036.000.70
41.021500.00-36.008.2036.000.68
50.811500.00-45.306.7035.900.66
60.681500.00-50.604.3036.000.62
70.571500.00-54.902.5035.900.58
80.401500.00-58.001.8036.000.58
90.381500.00-59.300.6035.900.56
100.001500.00-61.300.0035.800.51
Ngy th nghim: Xc nhn:
Th nghim 5STTLu lng Q (l/s)Tc bm n (rpm)p sut ht Ph (kPa)p sut y Pd(kPa)Nhit T (oC)Moment xon ng c t (N.m)
Kt qu kho st theo m van ch tc bm khng i
10.931050.00-3.509.7036.400.57
20.891050.00-3.3011.2036.100.58
30.781050.00-2.1016.2036.900.58
40.631050.00-0.5023.1036.200.54
50.521050.000.0026.2036.100.52
60.331050.001.4030.5036.500.50
70.201050.002.0031.8036.100.48
80.111050.002.0033.8036.300.48
90.071050.002.1034.0036.100.47
100.001050.002.2034.7036.300.47
Kt qu kho st theo ch tc bm m van hon ton
11.091350.00-6.9013.9036.000.71
21.051200.00-5.5011.6036.900.64
30.931050.00-3.808.9036.300.59
40.77900.00-2.107.4037.000.55
50.64750.00-1.005.3037.800.52
60.50600.000.103.9036.100.50
70.37450.001.002.8036.400.51
80.23300.001.601.9036.000.53
90.00150.002.001.3036.300.45
100.000.002.101.2035.100.01
Ngy th nghim:Xc nhn:
X L KT QU TH NGHIM Th nghim 1: Bng kt qu tnh ton s liu ( ch tc bm 70%)STTLu lng Q (l/s)H
HwHeHPhPmE
103.58820.00000.07503.66320.000049.45500.0000
20.193.42510.02200.07503.52216.564953.851012.1908
30.293.17020.05140.07503.29669.378554.950017.0673
40.462.98670.12920.07503.191014.399657.148025.1970
50.582.78290.20540.07503.063317.429658.247029.9236
60.652.58920.25800.07502.922218.633558.247031.9904
70.722.34450.31660.07502.736119.325860.445031.9725
80.822.03870.41060.07502.524420.306462.643032.4161
90.91.78390.49470.07502.353520.779462.643033.1712
100.941.60040.53960.07502.215020.425463.742032.0439
th
Th nghim 2 Bng kt qu tnh ton s liuSTTLu lng Q (l/s)H
HwHeHPhPmE
Kt qu kho st ch 50%
101.92660.00000.07502.00160.000035.32500.0000
20.091.75330.00490.07501.83331.618636.11004.4824
30.281.61060.04790.07501.73354.761536.110013.1862
40.371.47810.08360.07501.63675.940736.895016.1016
50.411.44750.10270.07501.62526.536537.680017.3475
60.461.33540.12920.07501.53966.947638.465018.0620
70.531.22320.17150.07501.46987.641838.465019.8670
80.581.10090.20540.07501.38147.859639.250020.0245
90.610.95820.22720.07501.26047.542640.035018.8400
100.660.88690.26600.07501.22797.949940.035019.8574
Kt qu kho st ch 60%
102.41590.00000.07502.49090.000043.33200.0000
20.212.31400.02690.07502.41594.977044.274011.2413
30.352.24260.07480.07502.39248.214445.216018.1669
40.432.07950.11290.07502.26749.564746.158020.7216
50.481.94700.14070.07502.162710.183746.158022.0627
60.561.89600.19150.07502.162511.880147.100025.2231
70.611.71250.22720.07502.014812.056647.100025.5979
80.641.61060.25010.07501.935712.153348.984024.8108
90.781.25380.37150.07501.700413.010848.984026.5614
100.811.14170.40070.07501.617412.851749.926025.7415
Kt qu kho st ch 80%
104.42410.00000.07504.49910.000060.28800.0000
20.174.19980.01760.07504.29247.158564.056011.1754
30.34.10810.05500.07504.238012.472565.312019.0968
40.354.00610.07480.07504.155914.269467.824021.0388
50.53.71050.15270.07503.938219.316770.336027.4635
60.563.60860.19150.07503.875121.288171.592029.7353
70.763.04790.35270.07503.475625.913074.104034.9684
80.852.73190.44120.07503.248127.084576.616035.3509
91.012.05910.62300.07502.757127.317477.872035.0799
101.11.89600.73890.07502.709929.243080.384036.3792
Kt qu kho st ch 90%
105.48420.00000.07505.55920.000076.30200.0000
20.25.12740.02440.07505.226810.255181.954012.5132
30.484.96430.14070.07505.180024.391784.780028.7706
40.544.80120.17810.07505.054326.774686.193031.0636
50.684.42410.28240.07504.781431.896089.019035.8306
60.744.12840.33440.07504.537832.942193.258035.3236
70.883.85320.47290.07504.401137.994096.084039.5425
80.983.34350.58650.07504.005038.503597.497039.4920
91.092.92560.72550.07503.726139.8432100.323039.7149
101.22.33440.87940.07503.288738.7149107.388036.0515
Kt qu kho st ch 100%
106.55450.00000.07506.62950.000073.79000.0000
20.216.13660.02690.07506.238512.852086.350014.8836
30.485.65750.14070.07505.873227.655787.920031.4555
40.65.43320.21980.07505.728133.7155100.480033.5544
50.665.42300.26600.07505.764037.3199103.620036.0161
60.814.97450.40070.07505.450243.3077103.620041.7947
70.884.69930.47290.07505.247245.2980108.330041.8148
80.944.36290.53960.07504.977545.8994109.900041.7647
90.984.28130.58650.07504.942847.5195109.900043.2389
101.32.56881.03200.07503.675946.8782120.890038.7776
th Th nghim 3 Bng kt qu tnh ton s liuSTTLu lng Q1(l/s)Tc bm n1Tc bm n2Ct p H1Thc nghimD on
Q2H2Q2H2
1010507503.663202.00160.001.8690
20.1910507503.52210.091.83330.141.7970
30.2910507503.29660.281.73350.211.6819
40.4610507503.19100.371.63670.331.6280
50.5810507503.06330.411.62520.411.5629
60.6510507502.92220.461.53960.461.4909
70.7210507502.73610.531.46980.511.3960
80.8210507502.52440.581.38140.591.2879
90.910507502.35350.611.26040.641.2008
100.9410507502.21500.661.22790.671.1301
VD: S liu d on dng 1:
th
Th nghim 4 Bng kt qu tnh ton s liuSTTLu lng Q (l/s)HinHvNPSHHsPhPmE
Kt qu kho st ch 20%
10.24163.100.0359263.87-0.020.2116.331.29
20.23132.520.0329294.450.020.2916.331.76
30.21122.320.0279304.650.000.2116.331.29
40.1971.360.0229355.620.040.2616.331.57
50.1640.770.0169386.210.060.2416.331.46
60.1330.580.0109396.410.060.1916.331.14
70.1120.390.0079406.610.080.1816.331.08
80.09-10.190.0059437.190.080.1416.330.87
90.07-20.390.0039447.380.100.1216.330.76
100-61.160.0009488.160.110.0016.330.00
Kt qu kho st ch 60%
10.81-224.260.4019650.860.9711.4749.9322.98
20.76-570.850.3539997.491.2012.1648.0425.30
30.68-958.210.28210384.921.4512.0448.0425.06
40.57-1325.180.19810751.981.8011.6246.1625.17
50.52-1681.960.16511108.792.1111.9946.1625.97
60.49-1804.280.14711231.132.0510.9145.2224.14
70.3-2150.870.05511577.812.287.1045.2215.71
80.21-2171.250.02711598.232.274.8943.3311.29
90.04-2242.610.00111669.612.360.9640.512.36
100-2466.870.00011893.872.570.0042.390.00
Kt qu kho st ch 100%
11.28-927.621.00110317.822.4844.61117.7537.88
21.25-1651.380.95411041.623.2953.00116.1845.61
31.09-2660.550.72612051.023.7448.56109.9044.19
41.02-3669.720.63513060.294.5152.19106.7648.89
50.81-4617.740.40114008.545.3045.90103.6244.30
60.68-5158.000.28214548.925.6039.7297.3440.80
70.57-5596.330.19814987.335.8534.2591.0637.61
80.4-5912.330.09815303.446.1024.6091.0627.01
90.38-6044.850.08815435.966.1123.3787.9226.58
100-6248.730.00015639.936.250.0080.070.00
th+ Ch kho st tc 20%:
+Ch kho st tc 60%:
+Ch kho st tc 100%:
Th nghim 5 Bng kt qu tnh ton s liuSTTLu lng Q (l/s)H
HwHeHPhPmE
Kt qu kho st theo m van ch tc bm khng i
10.931.34560.52820.07501.948717.779062.643028.3814
20.891.47810.48370.07502.036817.783163.742027.8986
30.781.86540.37150.07502.312017.690863.742027.7538
40.632.40570.24240.07502.723116.829559.346028.3583
50.522.67070.16510.07502.910914.848957.148025.9833
60.332.96640.06650.07503.107910.061154.950018.3095
70.23.03770.02440.07503.13716.155152.752011.6679
80.113.24160.00740.07503.32403.586952.75206.7996
90.073.25180.00300.07503.32982.286651.65304.4268
1003.31290.00000.07503.38790.000051.65300.0000
Kt qu kho st theo ch tc bm m van hon ton
11.092.12030.72550.07502.920831.2322100.323031.1316
21.051.74310.67330.07502.491425.662680.384031.9250
30.931.29460.52820.07501.897817.314064.841026.7022
40.770.96840.36210.07501.405510.616551.810020.4912
50.640.64220.25010.07500.96736.073340.820014.8783
60.50.38740.15270.07500.61503.016731.40009.6074
70.370.18350.08360.07500.34211.241724.02105.1691
80.230.03060.03230.07500.13790.311116.64201.8694
90-0.07140.00000.07500.00360.00007.06500.0000
100-0.09170.00000.0750-0.01670.00000.00000.0000
th
NHN XT V BN LUNTh nghim 1:1) Nhn xt v kt qu th nghim Cc dng ng biu dinu c dng ng cong. Mi quan h gia cc i lngLu lng ngy cng tng th chiu cao ct p ngy cng gim, hiu sut tng.Lu lng tng th p sut y v p sut ht ngc li gim xung.Momen xon v nhit bin i khng qu ln. im c hiu sut cao nhtim c hiu sut cao nht l, lu lng l.2) So snh th S ging nhaung hiu sut v ng ct p ct nhau ti 1 im.ng hiu sut vi ng cng sut c gi tr tng dn.ng ct p gim dn. S khc nhau Thc nghim: S sai s trong qu trnh o v tnh ton, dn n v th khng chnh xc. L thuytTh nghim 2:1) M t v nhn xt hnh dng cc ng hiu sut v cng sut2) So snh kt qu th nghim vi l thuyt.Th nghim 3:1) So snh kt qu d on vi kt qu o cC s sai lch v gi tr d on v thc t. dn n 2 ng d on v thc t khng trng nhau.Qu c th nhn thy, nhiu yu t ch quan nh hng n kt qu thc t.2) S chnh xc ca nhng gi tr xc nh c nh nh lut t l nh sau.3) Thun li v kh khn ca k thut ny cho vic thit k h thng bm.Th nghim 4:1) Hin tng xm thcKhi nim: xm thc l hin tng thng xy ra trong cc loi my thy lc nh bm l qu trnh ph hy tnh dy c ca dng chy cht lng do sinh ra trong dng chy nhng khoang cha y kh v hi ca cht lng.Nguyn nhn: s si v bc hi ca cht lng trong qu trnh my bm lm vic s gy nn hin tng xm thc.Qu trnh: p sut trong dng chy bng p sut bc hi bo ha -> nc si -> xut hin nhiu bt nc. Bt nc ngng t li thnh git nhng c th tch nh hn th tch git nc -> khong chn khng cc b xut hin. Lc ngng t, s va p ca cc phn t cht lng rt ln, m bin dng ca chng rt nh -> p lc rt ln -> song p lc ngc -> p lc gim, lm cht lng si li. iu dn n va p thy lc rt ln.Tc hi: Bo mn kt cu kim loi, lm cho kim loi han g nhanh hn. Lm cho bnh gung v b phn khc ca bm b h hi. To ra rung ng v ting n. Cng sut, hiu sut v ct p ca bm b gimo nhanh chng. Khi xm thc mnh, bm c th b hng. Thng s lm vic b gim t ngt. Gy ra va p thy lc.Cch phng chng: Khi lp t v s dng: Tng p sut vo my bm: dng ng ng ngn, c ng knh ln, t thit b chn, chiu cao lp my bm thp m bo cho kh khng lt t ngoi vo trong: theo ng ng ht v khe nt. Khi thit k v ch to: Tng ng knh ca bnh cng tc v chiu rng ca rnh. S dng vt liu c cng cao, thp khng g, ng thau2) Din t s nh hng ca vic thay i p sut ht ln qu trnh lm vic ca bm p sut ht ca bm c s nh hng rt ln n qu trnh lm vic ca bm. trnh hin tng xm thc, phi xc nh ng chiu cao ht hnh hc cho php. Chiu cao ht hnh hc thc t khng c vt qu chiu cao hnh hc cho php. Chiu di ng ht phi ngn n mc ti thiu, trnh lm nhiu ch i hng.3) Vic s dng biu NPSH trong vic thit k h thng v chn bm hp l. Vic s dng biu s gip khc phc hin tng xm thc. Gip kim tra bm d dng v thun tin hn. Vic kim tra xc nh NPSH s lin quan n vn hnh bm vi nc cc cng sut khc nhau, trong khi iu tit van ht. Gi tr ca NPSH s xc nh dc h thng c th ca bm s dng. Da vo NPSH ta c th iu chnh thng s cho hp l. l tang NPSH hn ch hin tng xm thc. Chng hn:Nu bm ht cht lng t 1 bnh kn cha p, ta tng lng cht lng trong bnh hoc tang p sut trn b mt cht lngGim nhit lm vic.Gim tn tht trn ng ng ht.4) iu kin hin tng xm thc xut hin. Do cht lng chuyn ng vo ming bm ly tm c p sut thp hn p sut kh quyn. Do s bc hi ca cht lng. Do trong cc my c p sut nh, nhit cao lm cho cht lng si,to nhiu bt kh. Do kh lt vo my bm t bn ngoi.
Th nghim 5:1) So snh th v c vi th l thuyt2) So snh giao im ng c tuyn mng ng vi ng ct p bm theo lu lng vi ng hiu sut bm.3) nh hng ca kt qu khi s dng gi tr trung bnh i vi van y. chnh xc thp. Dn n sai s trong vic o c tnh ton. Sai lch trong v th. Cc thng s khi tnh ton b nh hng.4) Phng php thay th i vi vic xc nh ng c tuyn ca h thng. xy dng ng c tuyn tnh ton xy dng ng c tuyn lm vic (n= const)5) S ph hp ca bm i vi h thng. Bm c cc thng s v kt cu ph hp vi h thng. C dng chy lin tc v u, cung cp khi lng nc ln vi p lc u ra khng i v p lc thp. C im lm vic n nh. Khi ng bm nhanh v iu chnh n gin trong khong lu lng ln. C th bm nhiu loi cht lng khc nhau, hn hp cht lng v cht rn. Nn mng nh khng chim nhiu din tch. Hiu sut lm vic cao.TI LIU THAM KHO[1]. Nguyn Bin- Tnh ton qu trnh, thit b trong cng nghip ha cht v thc phm- NXB khoa hc v k thut, H Ni, 1992.[2]. Tp th tc gi- S tay qu trnh v thit b cng ngh ha hc. Tp 1- NXB khoa hc v k thut, H Ni, 1992.[3]. Phm Vn Bn, Hong Minh Nam, V B Minh- Qa trnh v thit b cng ngh ha hc, tp 10: V d v bi tp. Trng i hc Bch Khoa thnh ph H Ch Minh, 1998.[4]. Cc qu trnh v thit b c hc- Trng i hc Cng Nghip TPHCM, 2011.PH LCCc cng thc tnh ton: Tnh ct p ton phn (H):Ct p ton phn ca bm c tnh nh sau:
Trong :
Ph : p sut ht, PaPd : p sut y, Pa
v1: vn tc ng ng ht ca dng lu cht, m/s
d1 l ng knh ng ht, d1= 0.0235mv2: vn tc ng ng y ca dng lu cht, m/s
d2 l ng knh ng y, d2= 0.0235m
Vi m hnh FM50 He = 0.075m Tnh cng sut thc ca bm Pm:
(W) < lu : Q tnh theo l/s >Vi: g: gia tc trng trng, m/s2khi lng ring ca nc, kg/m3Q: lu lng ca bm, m3/sH: ct p ton phn ca bm, m Cng sut l thuyt ca bm (Plt)
Vi:N: s vng quay ca bm, vng/phtM: momen xon ca ng c, N.m Tnh hiu sut ca bm (E):
S liu tra cuBi tnh mu Th nghim 1: Bin thin ct p thy tnh
Bin thin ng nng
Bin thin th nngHe=0.075m i vi m hnh FM50 Ct p ca bmH=Hs+ Hv+ He= 3.5882+0+0.075=3.6632m Cng sut thy lc truyn cho lu cht
Cng sut cn cung cp cho ng c
Hiu sut