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Type 316Ti(UNS 31635) ndi Titanium stabilized austenitic chromium-nickel stainless steel yokhala ndi molybdenum.Kuphatikizikako kumawonjezera kukana kwa dzimbiri, kumathandizira kukana kutulutsa ma ion chloride ndikupatsa mphamvu pakutentha kokwera.Katundu ndi ofanana ndi amtundu wa 316 kupatula kuti 316Ti chifukwa chakuwonjezera kwake kwa Titanium itha kugwiritsidwa ntchito pakutentha kokweza.Kukana kwa dzimbiri kumakhala bwino, makamaka motsutsana ndi sulfuric, hydrochloric, acetic, formic ndi tartaric acid, acid sulfates ndi alkaline chlorides.
Mapangidwe a Chemical:
| C | Si | Mn | P | S | Cr | Ni | Mo |
| ≤ 0.08 | ≤ 1.0 | ≤ 2.0 | ≤ 0.045 | ≤ 0.03 | 16.0 - 18.0 | 10.0 - 14.0 | 2.0 - 3.0 |
Katundu: Zowonjezera:
Kulimba Kwambiri Kwambiri: 75 KSI min (515 MPa min)
Mphamvu Zokolola: (0.2% Offset) 30 KSI min (205 MPa min)
Kutalika: 40% min
Kulimba: Rb 95 max
Masilayidi owonetsa zolemba zitatu pa slide iliyonse.Gwiritsani ntchito mabatani akumbuyo ndi ena kuti mudutse zithunzi, kapena mabatani owongolera masilayidi kumapeto kuti mudutse silayidi iliyonse.
Mu kafukufukuyu, hydrodynamics of flocculation imawunikidwa ndi kufufuza ndi manambala a chipwirikiti othamanga liwiro mu labotale sikelo paddle flocculator.Kuthamanga kwa chipwirikiti komwe kumalimbikitsa kuphatikizika kwa tinthu kapena kusweka kwa floc kumakhala kovuta ndipo kumaganiziridwa ndikufanizidwa mu pepalali pogwiritsa ntchito mitundu iwiri ya chipwirikiti, yomwe ndi SST k-ω ndi IDDES.Zotsatira zikuwonetsa kuti IDDES imapereka kusintha kwakung'ono kwambiri kuposa SST k-ω, komwe kumakhala kokwanira kutsanzira molondola kuyenda mkati mwa paddle flocculator.Mlingo woyenera umagwiritsidwa ntchito pofufuza kusinthika kwa zotsatira za PIV ndi CFD, ndikuyerekeza zotsatira za mtundu wa chipwirikiti wa CFD womwe wagwiritsidwa ntchito.Kafukufukuyu amayang'ananso kuchuluka kwa slip factor k, yomwe ndi 0.18 pa liwiro lotsika la 3 ndi 4 rpm poyerekeza ndi mtengo wamba wa 0.25.Kuchepetsa k kuchokera pa 0,25 mpaka 0.18 kumawonjezera mphamvu yoperekedwa kumadzimadzi pafupifupi 27-30% ndikuwonjezera liwiro la gradient (G) pafupifupi 14%.Izi zikutanthauza kuti chipwirikiti chochulukirapo chimaperekedwa kuposa momwe amayembekezera, chifukwa chake mphamvu zocheperako zimadyedwa ndipo chifukwa chake kugwiritsa ntchito mphamvu mu gawo la flocculation la chomera chamadzi akumwa kumatha kutsika.
Mu kuyeretsa madzi, Kuwonjezera coagulants destabilizes yaing'ono colloidal particles ndi zosafunika, amene ndiye kuphatikiza kupanga flocculation pa flocculation siteji.Flakes ndi momasuka womangidwa fractal aggregates misa, amene kenako kuchotsedwa ndi kuthetsa.Tinthu katundu ndi madzi kusanganikirana zinthu kudziwa dzuwa la flocculation ndi mankhwala ndondomeko.Kuyenda kumafuna kugwedezeka kwapang'onopang'ono kwa nthawi yochepa komanso mphamvu zambiri kuti zisokoneze madzi ambiri1.
Pa flocculation, ndi hydrodynamics a dongosolo lonse ndi umagwirira wa coagulant-tinthu mogwirizana kudziwa mlingo umene stationary tinthu kukula kugawa zimatheka2.Tinthu ting'onoting'ono tikagundana, timamatirana3.Oyegbile, Ay4 adanenanso kuti kugunda kumadalira njira zoyendera za Brownian kufalikira, kumeta ubweya wamadzimadzi komanso kukhazikika kosiyana.Ma flakes akawombana, amakula ndikufikira malire a kukula kwake, zomwe zingayambitse kusweka, chifukwa ma flakes sangathe kupirira mphamvu ya hydrodynamic forces5.Ena mwa ma flakes oswekawa amaphatikizananso kukhala ang'onoang'ono kapena kukula komweko6.Komabe, ma flakes amphamvu amatha kukana mphamvu iyi ndikusunga kukula kwake komanso kukula7.Yukselen ndi Gregory8 adanenanso za maphunziro okhudzana ndi kuwonongeka kwa flakes ndi kuthekera kwawo kukonzanso, kusonyeza kuti kusasinthika kuli kochepa.Bridgeman, Jefferson9 anagwiritsa ntchito CFD kuyerekeza mphamvu yakumaloko ya kuyenda kwapakati ndi chipwirikiti pakupanga ma floc ndi kugawikana kudzera m'magawo othamanga am'deralo.Mu akasinja okonzeka ndi masamba ozungulira, m`pofunika kusinthasintha liwiro limene aggregates kugunda ndi particles zina pamene mokwanira destabilized mu coagulation gawo.Pogwiritsa ntchito CFD komanso kuthamanga kwapang'onopang'ono kwa 15 rpm, Vadasarukkai ndi Gagnon11 adatha kukwaniritsa mtengo wa G wa conical paddle flocculation, potero kuchepetsa kugwiritsira ntchito mphamvu kwa chipwirikiti.Komabe, kugwira ntchito pamtengo wapamwamba wa G kungayambitse kusuntha.Iwo adafufuza momwe kusakanikirana kwa liwiro kumayendera pozindikira kuchuluka kwa liwiro la woyendetsa paddle flocculator.Amazungulira pa liwiro loposa 5 rpm.
Korpijärvi, Ahlstedt12 adagwiritsa ntchito mitundu inayi ya chipwirikiti kuti aphunzire gawo loyenda pa benchi yoyeserera ya thanki.Iwo anayeza gawo loyenda ndi laser Doppler anemometer ndi PIV ndikuyerekeza zotsatira zowerengedwa ndi zotsatira zoyezedwa.de Oliveira ndi Donadel13 apereka njira ina yoyezera kuthamanga kwamphamvu kuchokera kuzinthu za hydrodynamic pogwiritsa ntchito CFD.Njira yomwe idaperekedwa idayesedwa pamagawo asanu ndi limodzi a flocculation kutengera helical geometry.adawunika momwe nthawi yosungiramo ma flocculants amagwirira ntchito ndikupangira mtundu wa flocculation womwe ungagwiritsidwe ntchito ngati chida chothandizira kupanga ma cell omveka ndi nthawi yocheperako14.Zhan, You15 apereka lingaliro la CFD yophatikizika ndi mtundu wa kuchuluka kwa anthu kuti atsanzire mawonekedwe amayendedwe ndi machitidwe a floc mokhazikika.Llano-Serna, Coral-Portillo16 adafufuza za kayendedwe ka hydroflocculator yamtundu wa Cox m'malo opangira madzi ku Viterbo, Colombia.Ngakhale kuti CFD ili ndi ubwino wake, palinso malire monga zolakwika za manambala powerengera.Choncho, zotsatira zilizonse za manambala zomwe zapezedwa ziyenera kufufuzidwa mosamala ndi kufufuzidwa kuti zipeze mfundo zovuta17.Pali maphunziro ochepa m'mabuku okhudza mapangidwe a flocculators opingasa, pomwe malingaliro opangira ma hydrodynamic flocculators ndi ochepa18.Chen, Liao19 adagwiritsa ntchito khwekhwe loyesera potengera kufalikira kwa kuwala kwa polarized kuti ayeze momwe kuwala kwamwazikira kumayendera kuchokera ku tinthu tating'onoting'ono.Feng, Zhang20 adagwiritsa ntchito Ansys-Fluent kuyerekeza kugawa kwa mafunde a eddy ndikuzungulira m'malo oyenda a flocculator ya mbale zomangika komanso cholumikizira chamalata.Pambuyo poyerekezera kutuluka kwamadzimadzi mu flocculator pogwiritsa ntchito Ansys-Fluent, Gavi21 adagwiritsa ntchito zotsatira zake kupanga flocculator.Vaneli ndi Teixeira22 adanenanso kuti mgwirizano pakati pa mphamvu yamadzimadzi ya spiral tube flocculators ndi ndondomeko ya flocculation idakali yosadziwika bwino kuti igwirizane ndi mapangidwe omveka.de Oliveira ndi Costa Teixeira23 adaphunzira momwe angagwiritsire ntchito bwino ndikuwonetsa mphamvu za hydrodynamic za spiral chubu flocculator kudzera mu kuyesa kwafizikiki ndi zoyeserera za CFD.Ofufuza ambiri aphunzira za ma chubu ophimbidwa kapena ma flocculator ozungulira.Komabe, chidziwitso chatsatanetsatane cha hydrodynamic pamayankho a ma reactors awa pamapangidwe osiyanasiyana ndi magwiridwe antchito akadali akusowa (Sartori, Oliveira24; Oliveira, Teixeira25).Oliveira ndi Teixeira26 akupereka zotsatira zoyambirira kuchokera kumalingaliro amalingaliro, oyesera ndi ma CFD a spiral flocculator.Oliveira ndi Teixeira27 anaganiza zogwiritsa ntchito koyilo yozungulira ngati coagulation-flocculation reactor kuphatikiza ndi ochiritsira decanter system.Amanenanso kuti zotsatira zomwe zimapezedwa pakuchotsa turbidity ndizosiyana kwambiri ndi zomwe zimapezedwa ndi zitsanzo zomwe zimagwiritsidwa ntchito nthawi zambiri poyesa kusuntha, ndikuwonetsetsa kusamala mukamagwiritsa ntchito mitundu yotere.Moruzzi ndi de Oliveira [28] adatengera machitidwe a zipinda zoyenda mosalekeza pansi pazigawo zosiyanasiyana zogwirira ntchito, kuphatikiza kusiyanasiyana kwa zipinda zomwe zimagwiritsidwa ntchito komanso kugwiritsa ntchito ma cell okhazikika kapena ocheperako.Romphophak, Le Men29 PIV miyezo ya liwiro lanthawi yomweyo mu zotsuka za jet za quasi-two-dimensional.Iwo adapeza kufalikira kwamphamvu koyendetsedwa ndi jeti m'dera la flocculation ndikuyerekeza kumeta ubweya wamba komanso nthawi yomweyo.
Shah, Joshi30 akuti CFD imapereka njira ina yosangalatsa yosinthira mapangidwe ndikupeza mawonekedwe oyenda.Izi zimathandiza kupewa kuyika koyeserera kozama.CFD ikuchulukirachulukira kugwiritsidwa ntchito posanthula malo opangira madzi ndi madzi onyansa (Melo, Freire31; Alalm, Nasr32; Bridgeman, Jefferson9; Samaras, Zouboulis33; Wang, Wu34; Zhang, Tejada-Martínez35).Ofufuza angapo ayesa kuyesa zida (Bridgeman, Jefferson36; Bridgeman, Jefferson5; Jarvis, Jefferson6; Wang, Wu34) ndi perforated disc flocculators31.Ena agwiritsa ntchito CFD kuyesa ma hydroflocculators (Bridgeman, Jefferson5; Vadasarukkai, Gagnon37).Ghawi21 inanena kuti ma flocculators amakina amafunikira kukonzedwa pafupipafupi chifukwa nthawi zambiri amawonongeka ndipo amafuna magetsi ambiri.
Kuchita kwa paddle flocculator kumadalira kwambiri hydrodynamics ya posungira.Kusamvetsetsa kwachulukidwe kwa minda yothamanga mumayendedwe oterowo kumawonekera bwino m'mabuku (Howe, Hand38; Hendricks39).Unyinji wonse wamadzi umatengera kusuntha kwa flocculator impeller, kotero kutsetsereka kumayembekezereka.Kawirikawiri, kuthamanga kwamadzimadzi kumakhala kochepa kusiyana ndi liwiro la tsamba ndi slip factor k, yomwe imatanthauzidwa ngati chiŵerengero cha liwiro la thupi la madzi kupita ku liwiro la gudumu lopalasa.Bhole40 inanena kuti pali zinthu zitatu zosadziwika zomwe ziyenera kuganiziridwa popanga flocculator, zomwe ndi velocity gradient, drag coefficient, ndi mphamvu yamadzi yokhudzana ndi tsamba.
Camp41 imanena kuti poganizira makina othamanga kwambiri, liwiro limakhala pafupifupi 24% ya liwiro la rotor komanso mpaka 32% pamakina otsika kwambiri.Popanda septa, Droste ndi Ger42 adagwiritsa ntchito ak value ya 0.25, pomwe pa septa, k adachokera pa 0 mpaka 0.15.Howe, Hand38 ikuwonetsa kuti k ili pakati pa 0.2 mpaka 0.3.Hendrix39 idakhudzana ndi slip factor ndi liwiro lozungulira pogwiritsa ntchito njira yoyeserera ndipo adatsimikiza kuti slip factor inalinso mkati mwazomwe zidakhazikitsidwa ndi Camp41.Bratby43 inanena kuti k ndi za 0.2 kwa liwiro la impeller kuchokera ku 1.8 mpaka 5.4 rpm ndikuwonjezeka mpaka 0,35 pa liwiro la impeller kuchokera ku 0,9 mpaka 3 rpm.Ofufuza ena amafotokoza zamitundu yambiri yokoka (Cd) kuchokera pa 1.0 mpaka 1.8 ndikutsika koyenera k kuchokera pa 0.25 mpaka 0.40 (Feir ndi Geyer44; Hyde ndi Ludwig45; Harris, Kaufman46; van Duuren47; ndi 4 Brat8by ndi Marais8by ).Zolemba sizikuwonetsa kupita patsogolo kwakukulu pakutanthauzira ndi kuwerengera k kuyambira ntchito ya Camp41.
Njira ya flocculation imatengera chipwirikiti kuti athandizire kugundana, pomwe liwiro la liwiro (G) limagwiritsidwa ntchito kuyeza chipwirikiti/kusefukira.Kusakaniza ndi njira yogawanitsa mankhwala mwachangu komanso moyenera m'madzi.Mlingo wa kusakaniza umayesedwa ndi liwiro la gradient:
kumene G = liwiro la gradient (sec-1), P = kulowetsa mphamvu (W), V = kuchuluka kwa madzi (m3), μ = kukhuthala kwamphamvu (Pa s).
Kukwera kwa mtengo wa G, kumasakanikirana kwambiri.Kusakaniza kokwanira ndikofunikira kuti zitsimikizike kuti yunifolomu coagulation.Zolemba zikuwonetsa kuti magawo ofunikira kwambiri amapangidwe ndikusakaniza nthawi (t) ndi liwiro la liwiro (G).Njira ya flocculation imatengera chipwirikiti kuti athandizire kugundana, pomwe liwiro la liwiro (G) limagwiritsidwa ntchito kuyeza chipwirikiti/kusefukira.Mapangidwe amtundu wa G ndi 20 mpaka 70 s-1, t ndi 15 mpaka 30 mphindi, ndipo Gt (dimensionless) ndi 104 mpaka 105. Matanki osakanikirana othamanga amagwira bwino ntchito ndi G values za 700 mpaka 1000, ndikukhala ndi nthawi. pafupifupi 2 mphindi.
kumene P ndi mphamvu yoperekedwa ku madzi ndi tsamba lililonse la flocculator, N ndi liwiro lozungulira, b ndi kutalika kwa tsamba, ρ ndi kuchuluka kwa madzi, r ndi utali wozungulira, ndi k ndi slip coefficient.Equation iyi imayikidwa pa tsamba lililonse payekhapayekha ndipo zotsatira zake zimaphatikizidwa kuti zipereke mphamvu zonse za flocculator.Kufufuza mosamalitsa kwa equation iyi kukuwonetsa kufunikira kwa slip factor k pakupanga mapangidwe a paddle flocculator.Zolemba sizikunena mtengo weniweni wa k, koma m'malo mwake zimalimbikitsa mitundu monga momwe idanenedwera kale.Komabe, mgwirizano pakati pa mphamvu P ndi slip coefficient k ndi kiyubiki.Choncho, malinga ngati magawo onse ali ofanana, mwachitsanzo, kusintha k kuchokera ku 0,25 mpaka 0,3 kudzachepetsa mphamvu yomwe imaperekedwa kumadzimadzi pa tsamba ndi pafupifupi 20%, ndipo kuchepetsa k kuchokera ku 0,25 mpaka 0,18 kudzamuwonjezera.pafupifupi 27-30% pa vane Mphamvu yoperekedwa kumadzimadzi.Pamapeto pake, zotsatira za k pakupanga kokhazikika kwa paddle flocculator ziyenera kufufuzidwa kudzera mu kuchuluka kwaukadaulo.
Kuchulukitsidwa kolondola kwa slippage kumafunikira mawonekedwe oyenda komanso kayesedwe.Choncho, ndikofunika kufotokoza kuthamanga kwa tangential kwa tsamba m'madzi pa liwiro linalake lozungulira pamtunda wosiyana wa ma radial kuchokera pamtengowo komanso pakuya kosiyana kuchokera pamadzi kuti muwone zotsatira za malo osiyanasiyana a tsamba.
Mu kafukufukuyu, hydrodynamics of flocculation imawunikidwa ndi kufufuza ndi manambala a chipwirikiti othamanga liwiro mu labotale sikelo paddle flocculator.Miyezo ya PIV imalembedwa pa flocculator, ndikupanga mizere yozungulira nthawi yomwe ikuwonetsa kuthamanga kwa tinthu tamadzi tozungulira masamba.Kuphatikiza apo, ANSYS-Fluent CFD idagwiritsidwa ntchito kutsanzira kusuntha kozungulira mkati mwa flocculator ndikupanga ma contours anthawi yapakati.Chitsanzo cha CFD chotsatira chinatsimikiziridwa ndikuwunika makalata pakati pa zotsatira za PIV ndi CFD.Cholinga cha ntchitoyi ndikuwerengera kuchuluka kwa slip coefficient k, yomwe ndi gawo lopanda mawonekedwe la paddle flocculator.Ntchito yomwe yaperekedwa apa imapereka maziko atsopano owerengera slip coefficient k pa liwiro lotsika la 3 rpm ndi 4 rpm.Zotsatira za zotsatira zimathandizira mwachindunji kumvetsetsa kwa hydrodynamics ya tank flocculation.
The labotale flocculator tichipeza lotseguka pamwamba amakona anayi bokosi ndi wonse kutalika kwa 147 cm, kutalika kwa 39 cm, lonse m'lifupi 118 cm, ndi wonse kutalika 138 cm (mkuyu. 1).Njira zazikulu zopangira zida zopangidwa ndi Camp49 zidagwiritsidwa ntchito popanga ma labotale paddle flocculator ndikugwiritsa ntchito mfundo za kusanthula kwa dimensional.Malo oyeserawo adamangidwa ku Environmental Engineering Laboratory ya Lebanese American University (Byblos, Lebanon).
Mzere wopingasa uli pamtunda wa masentimita 60 kuchokera pansi ndipo umakhala ndi mawilo awiri opalasa.Gudumu lililonse lopalasa limakhala ndi zopalasa 4 zokhala ndi zopalasa zitatu papalasi lililonse pazambiri zokwana 12.Flocculation imafuna mukubwadamuka pang'ono pa liwiro la 2 mpaka 6 rpm.Kuthamanga kophatikizana kofala kwa ma flocculators ndi 3 rpm ndi 4 rpm.Ma laboratory scale flocculator flow adapangidwa kuti awonetsere kutuluka kwa tanki ya flocculation ya malo opangira madzi akumwa.Mphamvu imawerengedwa pogwiritsa ntchito equation yachikhalidwe 42.Pa ma liwiro onse awiri, liwiro la gradient \(\stackrel{\mathrm{-}}{\text{G}}\) ndi lalikulu kuposa 10 \({\text{sec}}^{-{1}}\) , chiwerengero cha Reynolds chimasonyeza kuyenda kwa chipwirikiti (Table 1).
PIV imagwiritsidwa ntchito kukwaniritsa miyeso yolondola komanso yochulukira ya velocity velocity yamadzimadzi nthawi imodzi pamlingo wokulirapo wa mfundo50.Kukonzekera koyesera kumaphatikizapo lab-scale paddle flocculator, LaVision PIV system (2017), ndi Arduino kunja laser sensor trigger.Kuti mupange mbiri yanthawi yayitali, zithunzi za PIV zidajambulidwa motsatizana pamalo omwewo.Dongosolo la PIV limawunikidwa kotero kuti malo omwe akulowera ali pakatikati pa kutalika kwa masamba atatu a mkono wina wopalasa.Choyambitsa chakunja chimakhala ndi laser yomwe ili mbali imodzi ya m'lifupi mwa flocculator ndi cholandirira sensor mbali inayo.Nthawi iliyonse mkono wa flocculator utsekereza njira ya laser, chizindikiro chimatumizidwa ku dongosolo la PIV kuti lijambule chithunzi ndi PIV laser ndi kamera yolumikizidwa ndi pulogalamu yowerengera nthawi.Pa mkuyu.2 ikuwonetsa kukhazikitsidwa kwa dongosolo la PIV ndi njira yopezera zithunzi.
Kujambula kwa PIV kunayambika pambuyo poti flocculator ikugwiritsidwa ntchito kwa 5-10 min kuti ikhale yoyenda bwino ndikuganizira gawo lomwelo la refractive index.Kuwongolera kumatheka pogwiritsa ntchito mbale yoyeserera yomizidwa mu flocculator ndikuyika pakatikati pa kutalika kwa tsamba lachidwi.Sinthani malo a PIV laser kuti mupange pepala lowala lathyathyathya pamwamba pa mbale yoyeserera.Lembani milingo yoyezedwa pa liwiro lililonse lozungulira la tsamba lililonse, ndipo liwiro lozungulira lomwe lasankhidwa kuti muyesere ndi 3 rpm ndi 4 rpm.
Pazojambula zonse za PIV, nthawi yotalikirana pakati pa ma pulse awiri a laser idayikidwa mumtundu wa 6900 mpaka 7700 µs, zomwe zidalola kuti tinthu tating'ono ting'onoting'ono 5 pixels.Mayesero oyendetsa ndege anachitidwa pa chiwerengero cha zithunzi zomwe zimafunikira kuti mupeze miyeso yolondola ya nthawi.Ziwerengero za Vector zidafaniziridwa ndi zitsanzo zomwe zili ndi 40, 50, 60, 80, 100, 120, 160, 200, 240, ndi 280 zithunzi.Kukula kwachitsanzo kwa zithunzi 240 kunapezeka kuti kumapereka zotsatira zokhazikika zanthawi yayitali popeza chithunzi chilichonse chili ndi mafelemu awiri.
Popeza kuti kutuluka kwa flocculator kumakhala kovuta, zenera laling'ono lofunsa mafunso ndi tinthu tambirimbiri timafunika kuthetsa zing'onozing'ono zowonongeka.Kuchulukitsa kangapo pakuchepetsa kukula kumagwiritsidwa ntchito limodzi ndi algorithm yolumikizirana kuti zitsimikizire zolondola.Zenera loyamba la mavoti a 48 × 48 pixels okhala ndi 50% kuphatikizika ndipo njira imodzi yosinthira idatsatiridwa ndi zenera lomaliza la 32 × 32 pixels ndi 100% kupindika ndi njira ziwiri zosinthira.Kuphatikiza apo, magalasi opanda magalasi adagwiritsidwa ntchito ngati tinthu tating'onoting'ono tomwe tikuyenda, zomwe zimalola kuti tinthu 10 pazenera lovotera.Kujambulira kwa PIV kumayambitsidwa ndi choyambitsa chomwe chili mkati mwa Programmable Timing Unit (PTU), yomwe imayang'anira ntchito ndikugwirizanitsa gwero la laser ndi kamera.
Phukusi lamalonda la CFD ANSYS Fluent v 19.1 linagwiritsidwa ntchito kupanga mtundu wa 3D ndikuthetsa ma equation oyambira.
Pogwiritsa ntchito ANSYS-Fluent, chitsanzo cha 3D cha labotale-scale paddle flocculator chinapangidwa.Chitsanzocho chimapangidwa ngati bokosi lamakona anayi, lomwe lili ndi mawilo awiri opalasa okwera pamtunda wopingasa, monga chitsanzo cha labotale.Mtundu wopanda bolodi ndi 108 cm wamtali, 118 cm mulifupi ndi 138 cm kutalika.Ndege yopingasa ya cylindrical yawonjezedwa mozungulira chosakaniza.Cylindrical ndege m'badwo uyenera kugwiritsa ntchito kasinthasintha wa chosakanizira lonse pa unsembe gawo ndi kutsanzira kasinthasintha otaya kumunda mkati flocculator, monga momwe mkuyu 3a.
3D ANSYS-yojambula bwino komanso yachitsanzo cha geometry, ANSYS-fluent flocculator body mesh pa ndege yosangalatsa, ANSYS-chithunzi chodziwika bwino pa ndege yosangalatsa.
Geometry yachitsanzo ili ndi zigawo ziwiri, zomwe ziri zamadzimadzi.Izi zimatheka pogwiritsa ntchito logic kuchotsa ntchito.Choyamba chotsani silinda (kuphatikiza chosakanizira) m'bokosi kuti muyimire madziwo.Kenako chotsani chosakanizira ku silinda, zomwe zimapangitsa kuti pakhale zinthu ziwiri: chosakanizira ndi madzi.Potsirizira pake, mawonekedwe otsetsereka anagwiritsidwa ntchito pakati pa madera awiriwa: mawonekedwe a cylinder-cylinder ndi mawonekedwe a cylinder-mixer (mkuyu 3a).
Kulumikizana kwa zitsanzo zomangidwa kwatsirizidwa kuti zigwirizane ndi zofunikira za chipwirikiti zomwe zidzagwiritsidwe ntchito poyendetsa mawerengero a manambala.Ukonde wosamangika wokhala ndi zigawo zokulitsidwa pafupi ndi malo olimba unagwiritsidwa ntchito.Pangani zigawo zowonjezera za makoma onse ndi kukula kwa 1.2 kuti muwonetsetse kuti zovuta zowonongeka zimagwidwa, ndi makulidwe oyambirira a \(7\mathrm{x}{10}^{-4}\) m kuonetsetsa kuti \ ( {\ zolemba {y))^{+}\le 1.0\).Kukula kwa thupi kumasinthidwa pogwiritsa ntchito njira yoyenera ya tetrahedron.Kutsogolo kwa mbali ziwiri zolumikizirana ndi kukula kwa 2.5 × \({10}^{-3}\) m kumapangidwa, ndi chosakanizira kukula kwake kwa 9 × \({10}^{-3}\) m amagwiritsidwa ntchito.Ma mesh opangidwa koyamba anali ndi zinthu za 2144409 (mkuyu 3b).
Mtundu wa chipwirikiti wa magawo awiri k–ε unasankhidwa ngati chitsanzo choyambirira.Kuti muyese molondola kuyendayenda kozungulira mkati mwa flocculator, chitsanzo chokwera mtengo chinasankhidwa.Kuthamanga kwa chipwirikiti mkati mwa flocculator kudafufuzidwa mowerengeka pogwiritsa ntchito mitundu iwiri ya CFD: SST k–ω51 ndi IDDES52.Zotsatira zamitundu yonseyi zidafaniziridwa ndi zoyeserera za PIV kuti zitsimikizire zitsanzo.Choyamba, mtundu wa chipwirikiti wa SST k-ω ndi mtundu wa chipwirikiti wamitundu iwiri wogwiritsa ntchito mphamvu zamadzimadzi.Uwu ndi mtundu wosakanizidwa wophatikiza mitundu ya Wilcox k-ω ndi k-ε.Ntchito yosakanikirana imayendetsa mtundu wa Wilcox pafupi ndi khoma ndi mtundu wa k-ε mumayendedwe omwe akubwera.Izi zimatsimikizira kuti chitsanzo cholondola chikugwiritsidwa ntchito pamtunda wonse.Imaneneratu molondola kupatukana kwamayendedwe chifukwa cha ma gradient owopsa.Kachiwiri, njira ya Advanced Deferred Eddy Simulation (IDDES), yomwe imagwiritsidwa ntchito kwambiri pamtundu wa Individual Eddy Simulation (DES) ndi SST k-ω RNS (Reynolds-Averaged Navier-Stokes) chitsanzo, inasankhidwa.IDDES ndi mtundu wosakanizidwa wa RNS-LES (chithunzi chachikulu cha eddy) chomwe chimapereka mawonekedwe osinthika komanso osavuta kugwiritsa ntchito (SRS).Zimatengera mtundu wa LES kuthetsa ma eddies akulu ndikubwerera ku SST k-ω kutengera ma eddies ang'onoang'ono.Kusanthula kwachiwerengero kwa zotsatira kuchokera ku SST k–ω ndi IDDES zofananira zinayerekezedwa ndi zotsatira za PIV kuti zitsimikizire chitsanzocho.
Mtundu wa chipwirikiti wa magawo awiri k–ε unasankhidwa ngati chitsanzo choyambirira.Kuti muyese molondola kuyendayenda kozungulira mkati mwa flocculator, chitsanzo chokwera mtengo chinasankhidwa.Kuthamanga kwa chipwirikiti mkati mwa flocculator kudafufuzidwa mowerengeka pogwiritsa ntchito mitundu iwiri ya CFD: SST k–ω51 ndi IDDES52.Zotsatira zamitundu yonseyi zidafaniziridwa ndi zoyeserera za PIV kuti zitsimikizire zitsanzo.Choyamba, mtundu wa chipwirikiti wa SST k-ω ndi mtundu wa chipwirikiti wamitundu iwiri wogwiritsa ntchito mphamvu zamadzimadzi.Uwu ndi mtundu wosakanizidwa wophatikiza mitundu ya Wilcox k-ω ndi k-ε.Ntchito yosakanikirana imayendetsa mtundu wa Wilcox pafupi ndi khoma ndi mtundu wa k-ε mumayendedwe omwe akubwera.Izi zimatsimikizira kuti chitsanzo cholondola chikugwiritsidwa ntchito pamtunda wonse.Imaneneratu molondola kupatukana kwamayendedwe chifukwa cha ma gradient owopsa.Kachiwiri, njira ya Advanced Deferred Eddy Simulation (IDDES), yomwe imagwiritsidwa ntchito kwambiri pamtundu wa Individual Eddy Simulation (DES) ndi SST k-ω RNS (Reynolds-Averaged Navier-Stokes) chitsanzo, inasankhidwa.IDDES ndi mtundu wosakanizidwa wa RNS-LES (chithunzi chachikulu cha eddy) chomwe chimapereka mawonekedwe osinthika komanso osavuta kugwiritsa ntchito (SRS).Zimatengera mtundu wa LES kuthetsa ma eddies akulu ndikubwerera ku SST k-ω kutengera ma eddies ang'onoang'ono.Kusanthula kwachiwerengero kwa zotsatira kuchokera ku SST k–ω ndi IDDES zofananira zinayerekezedwa ndi zotsatira za PIV kuti zitsimikizire chitsanzocho.
Gwiritsani ntchito choyezera chokhazikika chokhazikika ndikugwiritsa ntchito mphamvu yokoka munjira ya Y.Kuzungulira kumatheka pogawa ma mesh kusuntha kwa chosakaniza, pomwe magwero a nsonga yozungulira ali pakatikati pa nsonga yopingasa ndipo mayendedwe ozungulira ali mbali ya Z.Ma mesh amapangidwira mawonekedwe onse amtundu wa geometry, zomwe zimapangitsa kuti pakhale m'mphepete mwamabokosi awiri.Monga mu njira yoyesera, liwiro lozungulira limafanana ndi kusintha kwa 3 ndi 4.
Malire a makoma a osakaniza ndi flocculator anaikidwa ndi khoma, ndi kutsegula pamwamba pa flocculator anaikidwa ndi kubwereketsa ndi ziro n'zotsimikizira kuthamanga (mkuyu. 3c).SIMPLE pressure-velocity communication scheme, discretization of the gradient space of second-order function with all parameters based on the little square elements.Mulingo wa kuphatikizika kwa mitundu yonse yamayendedwe ndi masikelo a 1 x \({10}^{-3}\).Chiwerengero chachikulu cha kubwereza nthawi ndi 20, ndipo kukula kwa nthawi kumafanana ndi kuzungulira kwa 0.5 °.Yankho lake limasintha pa 8th iteration ya SST k–ω model ndi pa 12 iteration pogwiritsa ntchito IDDES.Komanso, chiwerengero cha masitepe nthawi anawerengedwa kuti chosakanizira anapanga zosachepera 12 zosintha.Gwiritsani ntchito sampuli za data paziwerengero za nthawi pambuyo pa kusinthasintha kwa 3, zomwe zimalola kuti kayendetsedwe kake kakhale kofanana ndi njira yoyesera.Kuyerekeza kutulutsa kwa ma loops othamanga pakusintha kulikonse kumapereka zotsatira zofananira pazosintha zinayi zomaliza, kuwonetsa kuti malo okhazikika afikira.Ma rev owonjezera sanawongolere ma contours othamanga.
Kuthamanga kwa nthawi kumatanthauzidwa molingana ndi liwiro la kuzungulira, 3 rpm kapena 4 rpm.Gawo la nthawi limayengedwa mpaka nthawi yofunikira kutembenuza chosakaniza ndi 0,5 °.Izi zimakhala zokwanira, chifukwa yankho limasinthasintha mosavuta, monga tafotokozera m'gawo lapitalo.Chifukwa chake, kuwerengera manambala onse amitundu yonse ya chipwirikiti kunachitika pogwiritsa ntchito njira yosinthidwa ya 0.02 \(\stackrel{\mathrm{-}}{7}\) ya 3 rpm, 0.0208 \(\stackrel{\mathrm{-} {3}\) 4 rpm.Pa sitepe yanthawi yoyeretsedwa, nambala ya Courant ya selo nthawi zonse imakhala yochepera 1.0.
Kuti mufufuze kudalira kwa ma model-mesh, zotsatira zidapezedwa koyamba pogwiritsa ntchito mauna oyambira a 2.14M kenako mauna oyeretsedwa a 2.88M.Kuwongolera ma gridi kumatheka pochepetsa kukula kwa selo la chosakaniza kuchokera ku 9 × \({10}^{-3}\) m mpaka 7 × \({10}^{-3}\) m.Kwa ma meshes oyambilira komanso oyengedwa amitundu iwiriyi chipwirikiti, pafupifupi ma module ama liwiro m'malo osiyanasiyana kuzungulira tsambalo adafaniziridwa.Kusiyana kwa maperesenti pakati pa zotsatira ndi 1.73% pa chitsanzo cha SST k–ω ndi 3.51% pa chitsanzo cha IDDES.IDDES imawonetsa kusiyana kwakukulu chifukwa ndi mtundu wosakanizidwa wa RNS-LES.Kusiyana kumeneku kunkaonedwa kuti n’kopanda ntchito, choncho kuyerekezera kunachitika pogwiritsa ntchito mauna oyambirira okhala ndi zinthu 2.14 miliyoni komanso nthawi yozungulira ya 0.5°.
Kubwerezanso kwa zotsatira zoyesera kunayesedwa poyesa mayesero asanu ndi limodzi kachiwiri ndikuyerekeza zotsatira.Fananizani kuchuluka kwa liwiro pakatikati pa tsamba pazoyeserera ziwiri.Kusiyana kwapakati pakati pa magulu awiri oyesera kunali 3.1%.Dongosolo la PIV lidasinthidwanso pawokha pakuyesera kulikonse.Yerekezerani liwiro lowerengeredwa pakatikati pa tsamba lililonse ndi liwiro la PIV pamalo omwewo.Kuyerekeza uku kukuwonetsa kusiyana ndi cholakwika chachikulu cha 6.5% pa tsamba 1.
Musanayambe kuwerengera chinthu chozembera, ndikofunikira kumvetsetsa mwasayansi lingaliro la kutsetsereka mu paddle flocculator, zomwe zimafunikira kuphunzira momwe zimayendera mozungulira ma paddles a flocculator.Conceptually, slip coefficient imamangidwa mu mapangidwe a paddle flocculators kuti aganizire kuthamanga kwa masamba okhudzana ndi madzi.Zolemba zimalimbikitsa kuti liwiro ili likhale 75% ya liwiro la tsamba, kotero mapangidwe ambiri amagwiritsa ntchito ak a 0.25 kuti afotokoze za kusinthaku.Izi zimafuna kugwiritsa ntchito ma streamline othamanga omwe amachokera ku kuyesa kwa PIV kuti amvetse bwino za liwiro la kuyenda ndikuwerenga slip iyi.Tsamba 1 ndi tsamba lamkati lomwe lili pafupi kwambiri ndi tsinde, tsamba 3 ndi lakunja, ndipo tsamba 2 ndi tsamba lapakati.
Kuthamanga kwa liwiro pa tsamba 1 kumawonetsa kuyenda mozungulira mozungulira tsambalo.Njira zoyendetsera izi zimachokera ku mfundo yomwe ili kumanja kwa tsamba, pakati pa rotor ndi tsamba.Kuyang'ana dera lomwe lasonyezedwa ndi bokosi la madontho ofiira mu Chithunzi 4a, ndizosangalatsa kuzindikira mbali ina ya kubwerezanso kumayenda pamwamba ndi kuzungulira tsambalo.Mawonekedwe oyenda amawonetsa kuyenda pang'ono muzone yobwereza.Kuthamanga uku kumayandikira kuchokera kumanja kwa tsambalo pamtunda wa pafupifupi 6 cm kuchokera kumapeto kwa tsamba, mwinamwake chifukwa cha chikoka cha tsamba loyamba la dzanja patsogolo pa tsamba, lomwe likuwonekera pachithunzichi.Mawonekedwe oyenda pa 4 rpm amawonetsa machitidwe ndi mawonekedwe omwewo, mwachiwonekere ndi liwiro lalitali.
Malo othamanga ndi ma graph amakono a masamba atatu pa liwiro la 3 rpm ndi 4 rpm.The pazipita pafupifupi liwiro masamba atatu pa 3 rpm ndi 0,15 m/s, 0,20 m/s ndi 0,16 m/s motero, ndi pazipita pafupifupi liwiro 4 rpm ndi 0,15 m/s, 0,22 m/s ndi 0,22 m/ s, motero.pa mapepala atatu.
Mtundu wina wa helical helical unapezeka pakati pa vanes 1 ndi 2. Gawo la vector limasonyeza bwino kuti madzi akuyenda mmwamba kuchokera pansi pa vane 2, monga momwe akuwonetsedwera ndi njira ya vector.Monga momwe zasonyezedwera ndi bokosi la madontho mu mkuyu 4b, ma vector awa samakwera chokwera kuchokera pamwamba pa tsamba, koma amatembenukira kumanja ndikutsika pang'onopang'ono.Pamwamba pa tsamba 1, ma vector otsika amasiyanitsidwa, omwe amayandikira masamba onse ndikuwazungulira kuchokera kumayendedwe obwereza omwe amapangidwa pakati pawo.Mayendedwe omwewo adatsimikiziridwa pamayendedwe onse ozungulira ndi matalikidwe apamwamba kwambiri a 4 rpm.
Kuthamanga kwa tsamba la 3 sikuthandiza kwambiri kuchokera ku velocity vector ya tsamba lapitalo lomwe likulowa pansi pa tsamba 3. Kuthamanga kwakukulu pansi pa tsamba 3 ndi chifukwa cha vector velocity vertical kukwera ndi madzi.
Ma velo velocity pamwamba pa tsamba 3 akhoza kugawidwa m'magulu atatu, monga momwe tawonetsera mkuyu 4c.Gawo loyamba ndikuyika pamphepete kumanja kwa tsamba.Mayendedwe oyenda pamalo awa ndiwolunjika kumanja ndi mmwamba (ie kulowera tsamba 2).Gulu lachiwiri ndi lapakati pa tsamba.Velocity ya malo awa imawongoleredwa molunjika, popanda kupatuka kulikonse komanso popanda kuzungulira.Kutsika kwa mtengo wa liwiro kunatsimikiziridwa ndi kuwonjezeka kwa msinkhu pamwamba pa mapeto a tsamba.Kwa gulu lachitatu, lomwe lili kumanzere kwa masamba, kutuluka kwake kumalunjika kumanzere, mwachitsanzo, ku khoma la flocculator.Kuthamanga kwakukulu komwe kumayimiridwa ndi vector velocity kumapita mmwamba, ndipo gawo lina lakuyenda limapita pansi.
Mitundu iwiri ya chipwirikiti, SST k–ω ndi IDDES, idagwiritsidwa ntchito kupanga mbiri yanthawi yayitali ya 3 rpm ndi 4 rpm mundege yotanthauza kutalika kwa tsamba.Monga momwe chithunzi 5 chikusonyezera, kukhazikika kumatheka mwa kukwaniritsa kufanana kotheratu pakati pa ma contours othamanga omwe amapangidwa ndi kasinthasintha anayi motsatizana.Kuonjezera apo, maulendo othamanga othamanga omwe amapangidwa ndi IDDES akuwonetsedwa mu Chithunzi 6a, pamene maulendo othamanga omwe amapangidwa ndi SST k - ω akuwonetsedwa mu Chithunzi 6a.6b .
Pogwiritsa ntchito ma IDDES ndi malupu othamanga anthawi yayitali opangidwa ndi SST k–ω, IDDES ili ndi gawo lalikulu la malupu othamanga.
Yang'anani mosamalitsa mbiri yothamanga yomwe idapangidwa ndi IDDES pa 3 rpm monga momwe tawonetsera pa Chithunzi 7. Chosakaniza chimayenda mozungulira mozungulira ndipo kutuluka kumakambidwa molingana ndi zolemba zomwe zikuwonetsedwa.
Pa mkuyu.7 zikhoza kuwoneka kuti pamwamba pa tsamba 3 mu I quadrant pali kulekanitsa kwa kuyenda, popeza kutuluka sikumangirizidwa chifukwa cha kupezeka kwa dzenje lapamwamba.Mu quadrant II palibe kupatukana kwa otaya kumawonedwa, popeza kutuluka kwake kumachepa ndi makoma a flocculator.Mu quadrant III, madzi amayenda mofulumira kwambiri kapena mofulumira kusiyana ndi quadrants yapitayi.Madzi mu quadrants I ndi II amasunthidwa (mwachitsanzo, kuzunguliridwa kapena kukankhidwira kunja) pansi ndi machitidwe a chosakanizira.Ndipo mu quadrant III, madzi amakankhidwira kunja ndi masamba a agitator.N'zoonekeratu kuti madzi misa mu malo kukana akuyandikira flocculator sleeve.Kuthamanga kozungulira mu quadrant iyi kumalekanitsidwa kwathunthu.Kwa quadrant IV, mpweya wambiri womwe uli pamwamba pa vane 3 umalunjika ku khoma la flocculator ndipo pang'onopang'ono umataya kukula kwake pamene kutalika kumawonjezeka mpaka kutsegulira pamwamba.
Kuonjezera apo, malo apakati amaphatikizapo machitidwe ovuta oyendayenda omwe amalamulira quadrants III ndi IV, monga momwe ma ellipses amadontho a buluu akuwonekera.Malo olembedwawa alibe chochita ndi kuyendayenda kwapaddle flocculator, monga momwe kugwedezeka kungathe kudziwika.Izi zikusiyana ndi quadrants I ndi II kumene pali kulekanitsa momveka bwino pakati pa kutuluka kwa mkati ndi kuyendayenda kwathunthu.
Monga zikuwonetsedwa mkuyu.6, poyerekeza zotsatira za IDDES ndi SST k-ω, kusiyana kwakukulu pakati pa maulendo othamanga ndi kukula kwa liwiro mwamsanga pansi pa tsamba 3. Chitsanzo cha SST k-ω chimasonyeza bwino kuti kuthamanga kwapamwamba kwambiri kumayendetsedwa ndi tsamba 3. poyerekeza ndi IDDES.
Kusiyana kwina kungapezeke mu quadrant III.Kuchokera ku IDDES, monga tafotokozera kale, kupatukana kozungulira pakati pa mikono ya flocculator kunadziwika.Komabe, malowa amakhudzidwa kwambiri ndi kuthamanga kwapansi kuchokera kumakona ndi mkati mwa tsamba loyamba.Kuchokera ku SST k–ω kumalo omwewo, mizere ya mizere imasonyeza mayendedwe okwera kwambiri poyerekeza ndi IDDES chifukwa palibe kutuluka kofanana kuchokera kumadera ena.
Kumvetsetsa bwino kwa magawo a velocity vector ndi ma streamlines ndikofunikira kuti mumvetsetse bwino kayendedwe ka kayendedwe kake ndi kapangidwe kake.Popeza kuti tsamba lililonse ndi 5 cm mulifupi, nsonga zisanu ndi ziwiri zimasankhidwa kudutsa m'lifupi mwake kuti zipereke mawonekedwe oyimira liwiro.Kuonjezera apo, kumvetsetsa kachulukidwe ka kukula kwa liwiro ngati ntchito ya kutalika pamwamba pa tsamba la tsamba kumafunika pokonza mbiri ya liwiro mwachindunji pamwamba pa tsamba lililonse ndi mtunda wopitirira wa 2.5 masentimita molunjika mpaka kutalika kwa 10 cm.Onani S1, S2 ndi S3 pachithunzichi kuti mudziwe zambiri.Zowonjezera A. Chithunzi 8 chikuwonetsa kufanana kwa kufalikira kwa liwiro la pamwamba pa tsamba lililonse (Y = 0.0) lomwe limapezeka pogwiritsa ntchito kuyesa kwa PIV ndi kusanthula kwa ANSYS-Fluent pogwiritsa ntchito IDDES ndi SST k-ω.Zitsanzo zonse ziwirizi zimapangitsa kuti zikhale zotheka kutsanzira molondola kayendedwe ka kayendedwe kake pamtunda wa masamba a flocculator.
Kugawa kwa liwiro PIV, IDDES ndi SST k–ω pamtunda wa tsamba.X-axis imayimira m'lifupi mwa pepala lililonse mu millimeters, ndipo chiyambi (0 mm) chikuyimira mbali yakumanzere ya pepala ndi mapeto (50 mm) kuyimira mbali yoyenera ya pepala.
Zikuwonekeratu kuti kugawidwa kwa liwiro la masamba 2 ndi 3 kukuwonetsedwa mu Fig.8 ndi Fig.8.S2 ndi S3 mu Zowonjezera A zimasonyeza zofanana ndi kutalika, pamene tsamba 1 limasintha palokha.Mawonekedwe a liwiro la masamba 2 ndi 3 amakhala owongoka bwino ndipo amakhala ndi matalikidwe omwewo pamtunda wa 10 cm kuchokera kumapeto kwa tsamba.Izi zikutanthauza kuti kutuluka kumakhala kofanana panthawiyi.Izi zikuwonekera bwino kuchokera ku zotsatira za PIV, zomwe zimatulutsidwa bwino ndi IDDES.Pakadali pano, zotsatira za SST k–ω zikuwonetsa zosiyana, makamaka pa 4 rpm.
Ndikofunika kuzindikira kuti tsamba la 1 limasunga mawonekedwe omwewo a liwiro la liwiro m'malo onse ndipo silikhala lokhazikika kutalika, popeza kuzungulira komwe kumapangidwa pakati pa chosakaniza kumakhala ndi tsamba loyamba la mikono yonse.Komanso, poyerekeza ndi IDDES, PIV blade speed profiles 2 ndi 3 adawonetsa kuthamanga pang'ono m'malo ambiri mpaka anali pafupifupi 10 cm pamwamba pa tsamba.
Nthawi yotumiza: Feb-26-2023