Thông tin tài liệu
N G H l i N CUTU-TRAO Ddi Ll/A CHQN MOT SO THONG SO KET CAU CO ANH HlTOTNG DEN HIEU SUAT VA KHA N A N C CHONG XAM THU'C CUA BaM HU^C^NG TRUC SELECTION OF STRUCTURAL PARAMETERS EFFECTED ON PERFORMANCE AND CAVITATION RESISTANCE OF AXIAL PUMP TS Ph^m Van Thu, TS Dinh Anh TaSin Vien Bcfm va Thilt bi Thu^ Itfi TOM TAT Bdm hudng true dddc sd dung rdng rdi mgi linh vUc cua nin kinh ti, nhdt Id vdn di tudi thuf l0i Khi tinh todn thiit ki, cd nhiiu thdng s6 quyit dinh chdt lUdng cda bd cdnh vd cdnh hUdng Tuy nhiin, cdc thdng s6 ndy vdo ndng lUc vd kinh nghiim cua ngddi thiit ki thudng dUdc Ida c khdc Sau ddy Id mdt s6 ldu f tinh todn lUa chgn ba bd thdng so diinh ciia bdm hUdng tr nude thdp: nD;^:L/T Tif kh6a: Bdm hudng true, mdy ddng ldc ABSTRACT Axial pump is widely used in allfields ofthe economy, especially in irrigation and drainage calculating design there are many parameters to determine the quality ofthe impeller and impelle direction However, these parameters are depended on ability and experience of the designer tha choosen different The following are some notes when calculating selected three parameters of t pump of low water column: nD;"; L/T Keywords: Axial pump, dynamic machine DJ^T VAN DE Bom hudng tryc la bdm dong chiy chuyen dpng qua phan din dong theo phiiong hiidfng tr\ic Bdm hudng tryc dUdc sit dung rpng rai mgi linh vUc cua nin kinh tl, hinh cho thay cac gam ham hudng true d\iac Liln X6 triiofc ddy nghien ciiu phu day cdc vung I^m vile cua cgt nii6c H tii 2,5m din 20m v^ liiu Iii^ng Q tif 1.800 mVh den 100.000 m'/h Cac bom nky diipc nghiin cilu cho vile v^n chuyin niidc dilu hoa cac Iiiu viic s6ng ldn, bom tudi tilu thuy ldi va diiOc cong bo g6m loai: O; OLI; BII va IIpB ^ T ^ P CHf CO KHl V I £ T NAM • S6 (Tiidng nam 2013) ^ NGHIEN ClJfU-TRAO Ddi Bang Cdc mdy bdm cdt nUde thdp thdng dung cua Liin Xd[6] Loai bdm Q(m'/s) H(m) n^ 05-47 1764-3996 3.75 -10.3 700 06-55 2232-5580 3.2 - 9.7 900 0 - 87 7488 - 13284 8.3-15.1 500 006-110 7956 - 22392 2.5 - 7.6 900 500 002-145 19260 - 38448 8.8 - 16.4 002-185 27720 - 54900 6.8 - 12.7 500 0011-185 52920 - 79920 12.7 - 20.4 800 0010-260 102240 - 152640 21 - 27.8 600 r Bang lilt kl cac gam bdm cua loai O va O n cho thay ti^u v l linh vUc bom cgt niidc th^ cua Lien X6 trUdc day Bdng Mot so bdm logi On7 cua Liin Xd cd cd n^ = lOOOv/ph [6] Loai bom Q(mVs) H(m) 0 - 35 1015 2.1 960 80 11 0 - 70 4100 2.2 485 80 44 0 - 87 6000 1.96 365 81 56 007-110 9570 1.9 290 82 88 n (v/ph) i Ll g|E:: ^2 * ^"== K^ ^^-r- -^^ a ! '^S^^^^i yJS" ^ K ^^ -~^^ < i >^; +H? \1 -^.Mi k^ —i m^ i"" ^4^ -^ ' 3=" -3 So-2a - V - ^ - i ^ ^ - s^ - ' " • • • ^^^ =^ MF c T"^ \ ^ tfffl •s ^-a^'35 TAP CHf CO KHi VIET NAM • S6 (Thang nam 2013) Cong suit N(kw) NGHIEN CUTU - TRAO D6I Hiln nay, hau hit cac tram bom Idn d Bic Bp vi Bac Khu cu deu sU dung may bdm hudng true, la cae loai bom hudng true ed Q tii lOOOmVh din cac loai 4.000mVh, S.OOOmVh, UOOOmVh, 25.000mVh va ldn nhat la Q = 36.000mVh, cpt ap biln tii 3m den 9m, phuc vy tudi, tilu hay tUdi tieu kit hgp Theo kit qua dilu tra hiln trang may bom va tr^im bom d Viet Nam Vien Khoa hgc Thuy Ipi thUc hien, tinh din nam 2004, d 16 tinh Bac Bp va Bae Khu Bon eii ed 4.964 tram bom vdi 13.305 may bdm cac loai, loai bdm hudng true cgt nUdc thap gdm hai lo^i: I D U C N G KfNH CANH BANH CONG TAC D VASOVONGQAYN Vdi cung mgt thdng so H va Q, cd the thilt kl cdnh banh cdng tdc cua bdm vdi cdc dUdng kinh D va so vdng quay n khac va dd chung se cd hilu suat thuy lUc khae Nhu v^y, vile Ida chpn thdng so D va so vdng quay n la rat quan trpng D va n khdng ehi bdi van tde v^, van toe v^ cao tUdng Ung vdi n Idn niu ta khdng tang D, dilu Iam tang ton that cdnh banh cdng tdc va ngUpc lai Thudng cdc mdy mdc cong nghiip ndi + Loai bdm hUdng tryc true dUng, lUu ehung va bom ndi rieng, xu hUdng cua ngUdi thiet lUdng tii 2000mVh din 32.000 mVh: g6m 408 kl Id cdn phdi eo gang dl kich thUdc cang nhd, cang ggn thi cang tdt Vay D khdng nen tang ma tram vdi 2305 may cd gang giam, dl giam D thi n phai tang + Loai bom hudng true true ngang va true Khao sdt cdc mdi quan he sau: xiln, ed lUu lUpng thilt ke tii 2.000m^/h trd xudng gom 243 tram vdi tong so 487 may[2] So vdng quay dUpc xdc dinh dUa theo he Nam 1996 - 2000, Trung tam Bom va May sd xam thUe ty tdc C: XSy dung, Vien Khoa hpc Thuy lpi ehu tri thUc 5^62[47e ,,, hien de tdi KHCN.05.01: "Nghien ciiu thilt kl va cong nghl ehi tao toan eum thilt bi bdm nUdc cd lUu lupng 36000m3/h" Dl tai da dugc chpn la C ( H M ) -,X (2) dl tai trpng dilm cap nha nUdc cua chUdng trinh " 5,624QA khoa hpe eong nghl 1996 - 2000, co thong s6 H = Doi vcfi bom hiidng true thong thudng: 6m, Q = 36.000mVh, N = 750 kW, n^ = 365 v/ph, = 85% vdi n^ gan lOOOv/ph [1] C » 1000; H^j = 10m Thanh cong bUdc dau ve viec nghien cdu A: He s6 dii tri2 lay 1.07 chl t£io bom ed hilu suat cao da ddng viin dpi ngu can bg tham gia cong tae nghien cdu Khi tinh toan thi^t ke canh banh cong tic, nhiem vu cua chiing ta li chpn vi ki€m tra n thoi man nho hon [n] theo cong thiic (2) Cd nhilu thong so kit cau quylt dinh ehat lupng mdt bg dan dong cda bdm hudng true Tiiy Dii6ng kinh D theo S.S.Rutnhiev dilpc thugc vao nang lUc va kinh nghiem eua ngUdi thiet kl thudng dUpc lUa chpn khae Sau ddy chpn v6i: la mdt so kinh nghi|m va kit qua due kit duoc v_ = (0,06 + 0,08) y«^e (3) qua trinh nghiin ciJfu dl tinh toan lUa chgn ba bg thdng s6 chinh eua bOm hudng true cpt Sau kiem tra nude thgp gdm: nD; d; LIT nD = 450 - 560 (4)=^ TAP CHl CO KHI V I £ T NAM V So (Thing nam 2013) NGHIEN C O U - T R A O D O I Trong qui trinh tinh toin thiet ke liia Viec giim ty s6 bau khong mang lai si chpn hai thong s6 D vi n theo cic cong thiJc (2), thay doi ding kl ve mat hieu suit cho binh cong (3), (4) deu cho ka qua tot tic Cac bom hudng true cpt nUdc thip c(S hieu suit cao cia Lien X6 cii cho thay ty so bau Kich thudc bau binh cong tic lay cing hieu qui nhat nam khoing 0.4 - 0.6 nh6 cing tot Sii giam nho ty so biu bi han che "Khi giim ty so bau tiJ 0.35 xudng 0.32 thi bdi hai nguydn nhin: hita suit giim khdng nhieu khoang 0.5%, nhitag Nguyen nhin thii nhat: Lim ting goc a giam ty so bau xudng 0.28 hieu suit ctng giam vi p„ qui miJc nen lam cho dong chiy dl bi tach ding ke 1.1%" "Vdi cirng gia trj Q^ neu d giam dong thi a giim "Nhiing ty so bau qui nhd cd the se giy hien tupng tich thinh cua ddng chiy d cac Nguyen nhin thii hai: Diidng kinh bau tiet dien sit bau lim tang ton that phii du de ldn hon dudng kinh true, du ldn de lap li canh vi co cau quay cinh bau d cac bom Ta thay rang giim d thi hilu suat co canh quay ting nhung khdng ding ke TY SO BAU d (KHto 22 A?\ 16 s N \ N 01 «0 N k 500 600 700 600 900 1000 1100 1200 1300 1400 1500 ns Hmh Do thi quan hi ((KJtu=f((n)[3] Kit qua tinh todn ly thuyet cho thay: bieu thdc: 0,Q38g', - Khi giam ty sd bdu (i tU 0.41 xudng 0.38 ^ (\-df thi hieu suat thuy lUc cua eanh bdnh cong tdc tang tii 89.40% lln 8^46% Nhu vay, giam ty so bau, hi|u suat ciia - Giam d xudng 0.35 va 0.32 thi hieu sudt banh cdng tae se tang nhUng khdng ddng kl tang them lan lUpt 0.05 va 0.04 Mat khde giam d den bao nhieu thi ho^ toan phu thupc vao kit cau cua bau bdnh cdng tic, Ty so bau anh hUdng den ca dac tinh nang nhat Id doi vdi loai bdm cdnh quay thi kha nang lupng va xam thUc thdng qua kha nang thodt Q va he sd xam thUc o dl giam ty so bau nhd hon d = 0.35 la khong Quan h | giQa cdc yeu to tren thi hiln qua hien thUe ^ TAP CHI CC KHI VIET NAM • Sd (Thang nam 2013) NGHIEN C O U - T R A O D O I Ngoai ra, viec gidm ty so bau se la dieu tang lln nhUng ton that loe thi lai giam NhU kiln rdt khd khan cho vile thiet kl kit cau quay v4y, phai ed mdt gid tri L/T nao dd dl tdng tdn canh, nhat la bdm cot nUdc thdp, luu lUdng that nang lUpng lUdi la nhd nhat Quan he Idn (L/T)p =f(K^) la kit qua giai phuong trinh vi phan tim dai lUdng ton that nang lUpng tUdng ddi Vay giam ty sd bau khdng mang Igii hilu nhd nhat lUdi qua dang ke, hilu suat tang rat it ThUdng tinh todn thiet kl ngUdi ta chpn ty sd bau d theo * Vdi mdi ludi prdfin cho tnidc cd mdt dp hinh va hinh lech gidi ban cua ddng chdy Ap, din gidi han dd ddng chay lUdi khdng bi tach ddng Mdi mdt gdc ngoat cho trUdc Ap vdi eac dieu kien khdc diu MAT DO DAY CANH L/T giong se tUdng dng vdi mdt gia tri nhd nhat * Mat dp day canh L/T cd anh hUdng ldn eua dp day lUdi L/T Vdi gid tri ddng chay chUa din mdc dp tdn that nang lUpng eanh bdnh bi tdch ddng cdng tdc Khi tang L/T thi tdn that ma sat se ^0706 0-5 04 H 0-05 01 15 02 'KHin 25 Hinh Do thi quan hid =f((KJ[3] ThUc tl da chiing minh rang: Khi thiet kl bom cd the lay gdc bang 80% gdc Idn nhat cd thi cd cua ludi da cho dl Iam gdc ngo^t cho phep cua ddng chdy Gde gpi la gde binh thudng va dupe ky hilu Ap^^ Gdc Ap^^ va ca APj^^, phu thudc vao cae thdng s6 kit cau cua lUdi: L/T va vao gde dat a Howelll da xdy dUng dupc dd thi xde dinh mat dp day eanh L/T nhd nhat eua lUdi theo cdc gid tri Ap va p^ Do thi la cdng cu de kiem tra gidi han dudi cua mat dp day cdnh L/T dam bdo cho ddng chdy lUdi khdng bi tdch ddng thay sU anh hUdng cua L/T ddi vdi a ^, nghia la anh hudng din chat lUpng xdm thUc cua day cdnh Quan he eho phep ta xdy dUng quan he a = f(K^)- Do thj ndy cho phep ddnh gid ehat lUdng xdm thUc se cd cua bdm dang thiet kl mat day eanh L/T chon theo dUdng cor^ (L/T) ^= f(K„) Tuy nhiln, day ehi la dilu kiln bat budc dl ddm bao canh khdng bi xdm thUc, van de la chpn Idn hdn la bao nhieu va Idn den bao nhilu la khdng nen Niu chung ta chi tinh den ma sdt thi L/T cdn anh hUdng din chdt L/T eang nhd cang cd lpi lupng xdm thUc cua day cdnh Quan he: Cdc cdng trinh nghiin cdu khoa hge va ngoai nUde nghiin cUu ve thdng so L/T cua 0555 T '^ eho bom va tuabin hUdng tryc da khang dinh: ' K„ L •(0 TAP CHf CO KHf VIETNAM • Sd (Thang nam 2013) NGHIEN C U T U - T R A O D O I - Gidm L/T trung bmh khoang 12% cho hiln bang mau eanh dupc chpn van chUa xay xam thUc, giam L/T 6% va 12%, hieu suat ldn nhat gidm diu - Tren ed sd phan tich ca hai khia canh hi^u 2%, tU 84,2% xudng 82% va 80,1% suat va xam thUe, ta nhan thay dp giam L/T (neu lay theo mau 0116) nen gidi han tdi da d khoang 10% -Niu giii nguyin tysd bau t/ , thay ddi L/T, Neu dp gidm L/T den 15% va Idn hdn thi chilu sau chieu eao hut se thay ddi theo, kit qua dUdc thi dat bom tang rat nhanh va ed gia tri rat ldn" T1TL{%) 029 0.32 0.35 0.38 41 (d/D) Hinh Anh hUdng cua ty so bdu din hieu sudt thup lUc cua cdnh [4] - Mdi mdt loai bom chi cd mdt gid tri L/T tdi Uu, tang thdng sd L/T so vdi gia tri tdi Uu, hieu suat eua bom se gidm di vd dp doc cua dUdng cong cdt dp se Idn hdn, ddc bilt vimg yen ngUa cd sU sai khdc rat ldn Khi giam thdng sd L/T so vdi gia tri tdi Uu, hilu suat ciia bdm eiing giam di, vd dp ddc dudng cong cdt dp eiing thoai hdn Bdng4: Cdc thongsimdu 1[7] Tiet dien Tilt di^n MOT S6 KET QUA NGHIEN CCtJ 4.1 Cac kit qua nghiin cUu thay ddi L/T loai each la Kit qud tinh todn L/T 0.97 0.8 0.73 37.302 30.194 0.69 0.65 22.208 Li (mm) 196.554 214.131 • 25.496 Ri(mm) 336.043 557.987 243.555 275.081 920.979 1441.496 301.404 2018.333 Cac mau dUpc tinh todn thd nghiem sau day cd thdng sd L/T thay ddi gidm dan, mau sau so vdi mau trUde 10% TAP CHi COKHJ VIETNAM a 49.206 Sd (Thing nim 2013) NGHigN ClAl - TRAO Ddi Bdng5:Cdcthdr^somlu2gidmL/T10%sovdimSul[7l H 100 S" Tlftdi^n L/T a 0.874 49.101 0.721 37.206 0.652 30.184 0.617 25.496 0.585 22.208 Tiftdi^n Li (mm) Ri(mm) 177.101 278.091 455.497 192.986 217.531 245.978 1128.807 271.264 1590.399 727.268 H = I(Q) ^ Ji " • • ' \ am Poly (n-l[Q)) 200 I DO o«) a » Q» o « OH, am Q ISnh 6: Ddc tinh ndng lUdng mdu 2[7} „t,uo N 50 ^'*.- T" ?< N * \ / • •**— Singd: Cdc thdngsdmiu 3gfdmUT20% so vdi mlu lp] Tilt di^n L/T a 0.777 48.985 0.641 37.228 0.58 30.194 0.548 25.547 0.52 22.208 Tilt dien Li (mm) Ri(mm) 225.714 157.446 171.572 193.51 571.987 218.47 871.481 241.124 1224.105 q am 0-80 0.70 0.60 050 040 030 020 0,20 010 0-30 040 Hinh 7: Dde tinh ndng lugng mdu [7] 4.2 Anh hudng chiiu cao hut thay dot L/T loai la canh 359.344 K& qua M nghiim dac tUi Bdng HJm) cua bdm thay dii L/T[7} TT Thdng sd L/T d =0.35, L/T khdng ddi d = 0.35, L/T giam 5% d = 0.35, L/T giim 10% H,,(m) 0.192 0.202 0.211 d = 0.35, L/T giim 15% d =0.35, L/T giim 20% 0.23 0.24 KET LUAN Hinh 5: Ddc tinh ndng lUdng mdu ll7] Nhiing phan tich va thi nghi|m tren day eho thay mdi quan h i ISn vd dnh hUdng cua cac thdng s6 k i t cdu canh eua eae lo^i may thuy'^ TAP CHf C O KHf V I £ T NAM • Sd (Thang nam 2013) NGHIEN Ctfu - T R A O D G I hieu chinh theo cich; luc hiidng true den die tinh ning IdOng v i hieu suit cvia chung NhQng phin tieh niy cimg cho thay: - D l ning eao hilu suit cila cic loai cinh miy thuy lUc hudng true can phai chu y tinh toin, lua chon cic thdng sd ket cau Tuy theo tinh nang m i lUa chon cic thdng sd niy theo hUdng tang hay giim so vdi cic bing bieu tham khio hay cac bom cd hilu suit eao tuong tU - Trong cic thdng sd kit ciu, L/T l i thdng sd quan trgng cd i n h hUdng chinh din chat luong thuy lUc v i xim thUe, v i dd den hieu suit ciia bd canh NhiJng bom thiet k l khdng tham khao duoc thdng sd L/T c i a bom mau tuong tU thi nen chon mau cd vdng quay die trdng gin nhat de dinh hUdng budc chon dau tien sau dd + Bdm thilt k l cd sd vdng quay die tning eao hon bom m i u thi chon L/T nhu bdm mau rui giim theo ty le til 10% d i n 20% v i t h i d i n bang m6 hinh toin hoac bang md hinh vit ly + Bom thiet ke cd sd vdng quay die tning nhd hon bom m i u thi chgn L/T nhU bom miu tang d i n theo ty le til 10% d i n 20% v i thvi din hang mo hinh toin hoac bang md hinh vat ly - LUa chgn nD theo hUdng D cing nhd cing tdt tren CO sd d i m b i o [n] - Trong cic loai cinh miy thuy lUc hUdng truerf~cang nhd cing tdt Tuy thudc vio kit cau il lUa chgn v i thdng sd niy khdng anh hUdng nhilu den hilu suit v i kha ning x i m thUc ciia bd cinh.*> Ngiy n h i n bii: 10/4/2013 Ngiy phin bien: 10/5/2013 NgUdi phan biln: GS, TS Nguyen The Mich, Bd mdn Miy v i TU ddng thuy khi, TrUdng Dai hgc Bich Khoa H i Ndi Tai lilu tham khao: [1] Pham Vzn Thu (2001), Bdo cdo de tdi nghien ciiu thiet kivd cdng nghi ciii tao bdm cd lUu lUOng 36(}00m% Vien Khoa hoc Thuy ldi Bo NN&PTNT [2] Pham \ ^ Thu (1997-2001), Bfloctiodi/(i«(fieu tra hiin trang mdy bdm tram bdm ngudn cung dng vd giai phdp phdt triin mdy bdm d Viet Nam, Vi|n khoa hoc thuy loi Bo NN&PTNT [3] A.A LOMAKIN, Ngudi dich: Le Phu, Ll Duy Tung, Dang Xuan Thi (1971), Bdm li tdm va bdm hUdngtrac NXB Khoa hpc Ky thuat [4] Nguyen Vu Viet (2004), Nghien citu md hinh tua bin hudng true de md rong pham vi iam viec cda tua bin hudng true cdt nUdc thdp itng dung cho cdc tram thuy dien nhd d Viet Nam, Luan an Tien si Ky thuit, TrUdng Dai hpc Bach Khoa Ha Npi [5] B A SHMHMUKOro M B A YMOsa (1986),/IOnACTHbIE HACOCbl, CnpaBO>!HMK ,neHiiHrpajl MaiuHHOCTpoeHHe TleHHHrpaflCKoe OTfleneHue [6] M.A.HMHaCB (1973),nOnACTHbIE HACOCbl, CnpaaoKHoe llocoT>Me JleuuHrpafl MamMHOCipoeHHe [7] Pham Van Thu(2008), Nghien cdu bdm hudng true cd ns ldn hdn 1000 dephuc vu tudi tieu cho diiu kiin cot nUdc thdp d Viet Nam, Luan an Tiln sy Ky thuat, TrUdng Dai hoc Bach Khoa Ha Npi TAP C H i CO KHi VIET NAM • Sd (Thing nam 2013)
Ngày đăng: 29/11/2022, 17:21
Xem thêm:
