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304 10 * 1mm Insimbi engagqwali ehlanganiswe ngamashubhu e-china
Usayizi: 3/4 intshi, 1/2 intshi, 1 intshi, 3 intshi, 2 amayintshi
Ubude bepayipi leyunithi: amamitha ayi-6
Ibanga Lensimbi: 201, 304 NO-316
Ibanga: 201, 202, 304, 316, 304L, 316 L,
Material: STAINLESS STEEL
Isimo: Okusha
Ikhoyili ye-Stainless Steel Tube
Usayizi: 3/4 intshi, 1/2 intshi, 1 intshi, 3 intshi, 2 amayintshi
Ubude bepayipi leyunithi: amamitha ayi-6
Ibanga Lensimbi: 201, 304 NO-316
Ibanga: 201, 202, 304, 316, 304L, 316 L,
Material: STAINLESS STEEL
Isimo: Okusha
Ama-nanofluid ane-covalent ne-non-covalent ahlolwe kumashubhu ayindilinga afakwe ama-tape asontekile anama-engeli we-helix angu-45° no-90°.Inombolo ye-Reynolds yayingu-7000 ≤ Re ≤ 17000, izakhiwo ze-thermophysical zihlolwe ku-308 K. Imodeli ebonakalayo ixazululwa ngezinombolo kusetshenziswa imodeli ye-viscosity yamapharamitha amabili (SST k-omega turbulence).Ukugxila (0.025 wt.%, 0.05 wt.%, kanye no-0.1 wt.%) we-nanofluids ZNP-SDBS@DV kanye ne-ZNP-COOH@DV kubhekwe emsebenzini.Izindonga zamashubhu asontekile zishiswa ekushiseni okungaguquki okungu-330 K. Imingcele eyisithupha yacatshangelwa ocwaningweni lwamanje: izinga lokushisa lokuphuma, i-coefficient yokudlulisa ukushisa, inombolo ye-Nusselt evamile, i-coefficient of friction, ukulahlekelwa kwengcindezi, kanye nenqubo yokuhlola ukusebenza.Kuzo zombili izimo (i-helix angle engu-45 ° no-90 °), i-ZNP-SDBS@DV nanofluid ibonise izici eziphakeme ze-thermal-hydraulic kune-ZNP-COOH@DV, futhi yanda ngokukhula kwengxenye yesisindo, isibonelo, i-0.025 wt., futhi 0.05 wt.ngo-1.19.% kanye no-1.26 – 0.1 wt.%.Kuzo zombili izimo (i-engeli ye-helix engu-45° no-90°), amanani ezici ze-thermodynamic uma usebenzisa i-GNP-COOH@DW angu-1.02 ku-0.025% wt., 1.05 ku-0.05% wt.kanye no-1.02 ngo-0.1% wt.
Isishintshi sokushisa siyidivayisi ye-thermodynamic 1 esetshenziselwa ukudlulisa ukushisa ngesikhathi sokupholisa nokushisisa imisebenzi.Izici ze-thermal-hydraulic zomshini wokushisa zithuthukisa i-coefficient yokudlulisa ukushisa futhi zinciphise ukumelana noketshezi olusebenzayo.Izindlela ezimbalwa zenzelwe ukuthuthukisa ukudluliswa kokushisa, okuhlanganisa izithuthukisi ze-turbulence2,3,4,5,6,7,8,9,10,11 kanye nama-nanofluids12,13,14,15.Ukufakwa kwe-twisted tape kungenye yezindlela eziphumelela kakhulu zokuthuthukisa ukudluliswa kokushisa kuma-exchangers okushisa ngenxa yokulula kwayo ukugcinwa kanye nezindleko eziphansi7,16.
Ochungechungeni lwezifundo zokuhlola kanye nezibalo, izakhiwo ze-hydrothermal zezingxube ze-nanofluid nezishintshisi zokushisa ezinokufakwa kwe-tape ezisontekile zafundwa.Emsebenzini wokuhlola, izakhiwo ze-hydrothermal ze-metallic nanofluid ezintathu ezihlukene (Ag@DW, Fe@DW kanye ne-Cu@DW) zahlolisiswa kumshini wokushisa yenaliti osontekile (STT)17.Uma kuqhathaniswa nepayipi lesisekelo, i-coefficient yokudlulisa ukushisa kwe-STT ithuthukiswa ngo-11% no-67%.Isakhiwo se-SST sihamba phambili ngokubuka kwezomnotho mayelana nokusebenza kahle nepharamitha α = β = 0.33.Ukwengeza, ukukhuphuka okungu-18.2% ku-n kubonwe nge-Ag@DW, nakuba ukwanda okuphezulu kokulahlekelwa kwengcindezi bekuyi-8.5% kuphela.Izinqubo ezingokoqobo zokudlulisa ukushisa nokulahlekelwa kwengcindezi kumapayipi agxilile anama-turbulator ahlanganisiwe nangenawo zacutshungulwa kusetshenziswa ukugeleza okunesiyaluyalu kwe-Al2O3@DW nanofluid ene-convection ephoqelelwe.Isilinganiso esiphezulu senombolo ye-Nuavg (i-Nuavg) kanye nokulahlekelwa kwengcindezi kubonwa ku-Re = 20,000 lapho ukuphakama kwekhoyili = 25 mm kanye ne-Al2O3@DW nanofluid 1.6 vol.%.Ucwaningo lwaselabhorethri luye lwenziwa futhi ukuze kucwaningwe ukudluliswa kokushisa nezici zokulahlekelwa kwengcindezi ye-graphene oxide nanofluids (GO@DW) egeleza cishe ngamashubhu ayindilinga ane-WC inserts.Imiphumela ibonise ukuthi u-0.12 vol%-GO@DW unyuse i-coefficient yokudlulisa ukushisa okuguquguqukayo cishe ngo-77%.Kolunye ucwaningo lokuhlola, ama-nanofluids (TiO2@DW) athuthukiswa ukuze kufundwe izici ezishisayo-hydraulic zamashubhu ane-dimple afakwe okufakwayo okusontekile20.Ukusebenza kahle okuphezulu kwe-hydrothermal kwe-1.258 kufinyelelwe kusetshenziswa i-0.15 vol%-TiO2@DW eshumekwe ku-45 ° shafts ethambekele ene-twist factor ye-3.0.Amamodeli okulingisa esigaba esisodwa kanye nesigaba ezimbili (hybrid) acabangela ukugeleza nokudlulisa ukushisa kwe-CuO@DW nanofluids ekugxilweni okuqinile okuqinile (1–4% vol.%)21.Ukusebenza okuphezulu kokushisa kwethubhu efakwe nge-tape eyodwa esontekile yi-2.18, futhi ithubhu efakwe ngamateyipu amabili asontekile ngaphansi kwezimo ezifanayo yi-2.04 (imodeli yezigaba ezimbili, Re = 36,000 kanye ne-4 vol.%).Ukugeleza kwe-nanofluid okungeyona kwe-Newtonian okunyakazayo kwe-carboxymethyl cellulose (CMC) ne-copper oxide (CuO) kumapayipi amakhulu namapayipi anokufakwa okusontiwe kuhlolisisiwe.I-Nuavg ibonisa ukuthuthuka okungu-16.1% (kumapayipi amakhulu) kanye no-60% (kumapayipi ahlanganisiwe anesilinganiso esingu-(H/D = 5)).Ngokuvamile, isilinganiso esiphansi se-twist-to-ribbon siholela ku-coefficient ephezulu yokungqubuzana.Ocwaningweni lokuhlola, umthelela wamapayipi anetheyiphu esontiwe (TT) namakhoyili (VC) ezicini zokudlulisa ukushisa kanye ne-coefficient yokungqubuzana kwacwaningwa kusetshenziswa i-CuO@DW nanofluids.Isebenzisa i-0.3 vol.I-% -CuO @ DW ku-Re = 20,000 yenza kube lula ukwandisa ukudluliswa kokushisa kupayipi ye-VK-2 ibe yinani eliphakeme lama-44.45%.Ukwengeza, uma usebenzisa ikhebula elisontekile kanye nokufakwa ikhoyili ngaphansi kwezimo zomngcele ofanayo, i-coefficient of friction inyuka ngezici ezingu-1.17 no-1.19 uma kuqhathaniswa ne-DW.Ngokuvamile, ukusebenza kahle kokushisa kwama-nanofluid afakwe kumakhoyili kungcono kunalawo ama-nanofluid afakwe ezintanjeni eziboshiwe.Isici sevolumu yokugeleza kwe-nanofluid enyakazayo (MWCNT@DW) yacwaningwa ngaphakathi kweshubhu evundlile efakwe ocingweni oluzungezayo.Amapharamitha wokusebenza okushisayo ayengu-> 1 kuzo zonke izimo, okubonisa ukuthi inhlanganisela ye-nanofluidics ne-coil insert ithuthukisa ukudluliswa kokushisa ngaphandle kokusebenzisa amandla epompo.I-Abstract—Izici ze-hydrothermal zesishintshi sokushisa samapayipi amabili nezifakwa ezihlukahlukene ezenziwe ngetheyiphu eguquliwe esontekile emise okwe-V (VcTT) zihlolisiswe ngaphansi kwezimo zokugeleza okunesiyaluyalu kwe-Al2O3 + TiO2@DW nanofluid.Uma kuqhathaniswa ne-DW kumashubhu ayisisekelo, i-Nuavg inokuthuthukiswa okuphawulekayo kwe-132% kanye ne-friction coefficient efika ku-55%.Ngaphezu kwalokho, ukusebenza kahle kwamandla kwe-Al2O3+TiO2@DW nanocomposite emshinini wokushisisa wamapayipi amabili26 kwaxoxwa ngawo.Ocwaningweni lwabo, bathole ukuthi ukusetshenziswa kwe-Al2O3 + TiO2@DW kanye ne-TT kuthuthukisa ukusebenza kahle kokusebenza uma kuqhathaniswa ne-DW.Ezishintshisini zokushisa ze-tubular ezigxilile ezinama-turbulators e-VcTT, uSingh no-Sarkar27 basebenzisa izinto zokushintsha isigaba (PCM), bahlakaze ama-nanofluids angawodwa/nanocomposite (Al2O3@DW nge-PCM kanye ne-Al2O3 + PCM).Babike ukuthi ukudluliswa kokushisa nokulahlekelwa kwengcindezi kukhuphuka njengoba i-twist coefficient iyancipha futhi ukuhlushwa kwe-nanoparticle kuyanda.Isici esikhulu sokujula kwe-V-notch noma isici sobubanzi esincane singanikeza ukudluliswa okukhulu kokushisa nokulahlekelwa kwengcindezi.Ukwengeza, i-graphene-platinum (Gr-Pt) isetshenziselwe ukuphenya ukushisa, ukungqubuzana, kanye nesilinganiso sokukhiqizwa kwe-entropy jikelele kumashubhu anokufakwa kwe-2-TT28.Ucwaningo lwabo lubonise ukuthi iphesenti elincane le-(Gr-Pt) lehlise kakhulu isizukulwane sokushisa se-entropy uma kuqhathaniswa nokuthuthukiswa kwe-entropy ephakeme kakhulu.I-Mixed Al2O3@MgO nanofluids kanye ne-conical WC ingabhekwa njengengxube enhle, njengoba isilinganiso esengeziwe (h/Δp) singathuthukisa ukusebenza kwe-hydrothermal yesishintshi sokushisa samashubhu amabili 29.Imodeli yezinombolo isetshenziselwa ukuhlola ukonga amandla nokusebenza kwemvelo kwezishintshi zokushisa ezinezingxenye ezintathu ezihlukahlukene ze-hybrid nanofluids (THNF) (Al2O3 + graphene + MWCNT) ezimiswe okwesikhashana ku-DW30.Ngenxa Yemibandela Yokuhlola Ukusebenza kwayo (i-PEC) ebangeni elingu-1.42–2.35, inhlanganisela ye-Depressed Twisted Turbulizer Insert (DTTI) kanye (Al2O3 + Graphene + MWCNT) iyadingeka.
Kuze kube manje, ukunakwa okuncane kukhokhwe endimeni yokusebenza kwe-covalent ne-non-covalent ekugelezeni kwe-hydrodynamic emanzini ashisayo.Inhloso ethize yalolu cwaningo kwakuwukuqhathanisa izici ezishisayo ze-thermal-hydraulic ze-nanofluids (ZNP-SDBS@DV) kanye (ZNP-COOH@DV) ekufakweni kwe-tape esontekile ngama-engeli we-helix angu-45 ° no-90 °.Izakhiwo ze-thermophysical zikalwa ku-Tin = 308 K. Kulesi simo, izingxenye ezintathu zesisindo zicatshangelwe ekuqhathaniseni inqubo, njengokuthi (0.025 wt.%, 0.05 wt.% kanye no-0.1 wt.%).Ukudluliswa kokucindezeleka kwe-shear kumodeli ye-3D turbulent flow model (SST k-ω) isetshenziselwa ukuxazulula izici ze-thermal-hydraulic.Ngakho-ke, lolu cwaningo luba neqhaza elikhulu ekutadisheni izakhiwo ezinhle (ukudluliselwa kokushisa) kanye nezakhiwo ezingezinhle (ukwehla kwengcindezi ekungqubuzaneni), okubonisa izici ezishisayo-hydraulic kanye nokwenza kahle koketshezi olusebenzayo lwangempela kuzinhlelo ezinjalo zobunjiniyela.
Ukucushwa okuyisisekelo kuyipayipi elibushelelezi (L = 900 mm no-Dh = 20 mm).Kufakwe izilinganiso zetheyiphu esontekile (ubude = 20 mm, ukujiya = 0.5 mm, iphrofayili = 30 mm).Kulesi simo, ubude, ububanzi, kanye nokushaywa kwephrofayili ye-spiral kwakungama-20 mm, 0.5 mm, no-30 mm, ngokulandelana.Amateyipu asontekile athambekele ku-45° no-90°.Uketshezi oluhlukahlukene olusebenzayo njenge-DW, i-non-covalent nanofluids (GNF-SDBS@DW) nama-covalent nanofluids (GNF-COOH@DW) e-Tin = 308 K, ukugxiliswa kwesisindo okuthathu okuhlukene kanye nezinombolo zamaReynolds ahlukene.Ukuhlolwa kwenziwa ngaphakathi kwesishintshi sokushisa.Udonga lwangaphandle lweshubhu elivunguzayo lwashiswa ngokushisa okungaguquki kwendawo engu-330 K ukuze kuhlolwe imingcele yokuthuthukisa ukudluliswa kokushisa.
Emkhiwaneni.1 ikhombisa ngokohlelo ishubhu lokufaka itheyiphu esontekile elinemibandela yomngcele esebenzayo nendawo enemedali.Njengoba kushiwo ngaphambili, izimo ze-velocity ne-pressure boundary zisebenza ezingxenyeni zokungena nokuphuma kwe-helix.Emazingeni okushisa angaphezulu, isimo esingaguquki sibekwe odongeni lwamapayipi.Ukulingisa kwamanje kwezinombolo kusebenzisa isisombululo esisekelwe kungcindezi.Ngesikhathi esifanayo, uhlelo (i-ANSYS FLUENT 2020R1) lusetshenziswa ukuguqula i-partial differential equation (PDE) ibe uhlelo lwezibalo ze-algebra kusetshenziswa indlela yevolumu elinganiselwe (FMM).Indlela ye-SIMPLE ye-oda lesibili (indlela engacacile yezibalo ezincike kungcindezi elandelanayo) ihlobene ne-velocity-pressure.Kufanele kugcizelelwe ukuthi ukuhlangana kwezinsalela zezibalo zesisindo, umfutho, namandla kungaphansi kuka-103 no-106, ngokulandelana.
p Umdwebo wezizinda ezibonakalayo nezibalo: (a) i-engeli ye-helix 90°, (b) i-engeli ye-helix 45°, (c) ayikho i-helical blade.
Imodeli ye-homogeneous isetshenziselwa ukuchaza izakhiwo ze-nanofluids.Ngokuhlanganisa ama-nanomaterials ku-base fluid (DW), kwakheka uketshezi oluqhubekayo olunezici ezinhle kakhulu zokushisa.Mayelana nalokhu, izinga lokushisa kanye nesivinini se-base fluid kanye ne-nanomaterial kunenani elifanayo.Ngenxa yale mibono engenhla kanye nokuqagela, ukugeleza kwesigaba esisodwa okusebenzayo kusebenza kulolu cwaningo.Ucwaningo oluningana lubonise ukusebenza kahle nokusetshenziswa kwamasu esigaba esisodwa sokugeleza kwe-nanofluidic31,32.
Ukugeleza kwama-nanofluid kumele kube yisiphithiphithi saseNewton, kungenakucindezelwa futhi kumile.Umsebenzi wokuminyanisa nokushisisa kwe-viscous akubalulekile kulolu cwaningo.Ngaphezu kwalokho, ubukhulu bezindonga zangaphakathi nangaphandle zepayipi abunakwa.Ngakho-ke, ubukhulu, umfutho, kanye nezibalo zokongiwa kwamandla ezichaza imodeli yokushisa zingavezwa ngale ndlela elandelayo:
lapho \(\overrightarrow{V}\) iyivektha yesivinini esimaphakathi, i-Keff = K + Kt iwukuguquguquka okushisayo okusebenzayo kwama-nanofluid ama-covalent nama-noncovalent, futhi u-ε izinga lokuchithwa kwamandla.Izici ezisebenzayo ze-thermophysical zama-nanofluid, okuhlanganisa ukuminyana (ρ), i-viscosity (μ), umthamo wokushisa othize (Cp) kanye ne-thermal conductivity (k), eboniswe kuthebula, kukalwa phakathi nocwaningo lokuhlola ezingeni lokushisa elingu-308 K1 lapho kusetshenziswa. kulezi zifanisi.
Ukulingiswa kwezinombolo kokugeleza kwe-nanofluid eneziyaluyalu kumashubhu avamile kanye ne-TT kwenziwa ngezinombolo ze-Reynolds 7000 ≤ Re ≤ 17000. Lokhu kulingiswa kanye nama-coefficients okudlulisa ukushisa okuguquguqukayo kwahlaziywa kusetshenziswa imodeli ye-Mentor's κ-ω turbulence ye-shear averaged stress transfer (Sturynold) ukudluliswa kokucindezeleka okumaphakathi (Sturynold) imodeli ye-Navier-Stokes, evame ukusetshenziswa ocwaningweni lwe-aerodynamic.Ngaphezu kwalokho, imodeli isebenza ngaphandle komsebenzi wodonga futhi inembile eduze kwezindonga 35,36.(SST) κ-ω elawula izilinganiso zemodeli yesiphithiphithi yilena elandelayo:
lapho \(S\) kuyinani lesilinganiso sobunzima, futhi \(y\) iyibanga eliya endaweni eseduze.Ngaleso sikhathi, \({\alpha}_{1}\), \({\alpha}_{2}\), \({\beta}_{1}\), \({\beta}_{ 2) }\), \({\beta}^{*}\), \({\sigma}_{{k}_{1}}\), \({\sigma}_{{k}_{ 2) }}\), \({\sigma}_{{\omega}_{1}}\) kanye \({\sigma}_{{\omega}_{2}}\) isho wonke amamodeli angaguquki.I-F1 ne-F2 yimisebenzi exubile.Qaphela: F1 = 1 kusendlalelo somngcele, 0 ekuhambeni okuzayo.
Amapharamitha okuhlola ukusebenza asetshenziselwa ukutadisha ukudluliswa kokushisa kwe-convective okuneziyaluyalu, ukugeleza kwe-covalent nokungahlangani kwe-nanofluid, isibonelo31:
Kulo mongo, (\(\rho\)), (\(v\)), (\({D}_{h}\))) kanye (\(\mu\)) asetshenziselwa ukuminyana, isivinini soketshezi. , ububanzi be-hydraulic kanye ne-viscosity eguquguqukayo.(\({C}_{p}\, \mathrm{u}\, k\)) - umthamo wokushisa othize kanye ne-thermal conductivity yoketshezi olugelezayo.Futhi, (\(\dot{m}\)) ibhekisela ekugelezeni okukhulu, futhi (\({T}_{out}-{T}_{in}\)) ibhekisela kumehluko wezinga lokushisa lokungena nokuphumayo.(i-NFs) ibhekisela kuma-nanofluid ahlangene, angahlali ndawonye, futhi (i-DW) ibhekisela emanzini acwecwe (uketshezi oluyisisekelo).\({A}_{s} = \pi DL\), \({\ ngaphezulu kwe-inthanethi{T}}_{f}=\frac{\left({T}_{ngaphandle}-{T}_{in }\kwesokudla)}{2}\) kanye \({\ overline{T}_{w}=\sum \frac{{T}_{w}}{n}\).
Izakhiwo ze-thermophysical ze-base fluid (DW), i-non-covalent nanofluid (GNF-SDBS@DW), kanye ne-covalent nanofluid (GNF-COOH@DW) zithathwe ezincwadini ezishicilelwe (izifundo zokuhlola), Sn = 308 K, njengoba kukhonjiswe kuThebula 134. Esimweni esijwayelekile Esivivinyweni sokuthola i-non-covalent (GNP-SDBS@DW) nanofluid enamaphesenti obunzima aziwayo, amagremu athile ama-GNP ayisisekelo aqale akalwa ngebhalansi yedijithali.Isilinganiso sesisindo se-SDBS/GNP yomdabu ngu-(0.5:1) esikalini nge-DW.Kulokhu, ama-nanofluids e-covalent (COOH-GNP@DW) ahlanganiswa ngokungeza amaqembu e-carboxyl ebusweni be-GNP kusetshenziswa indawo ene-asidi eqinile enesilinganiso sevolumu (1:3) se-HNO3 ne-H2SO4.Ama-nanofluid ane-covalent nama-non-covalent amisiwe ku-DW ngamaphesenti amathathu esisindo ahlukene afana no-0.025 wt%, 0.05 wt%.kanye no-0.1% wesisindo.
Ukuhlolwa kokuzimela kwe-mesh kwenziwa ezizindeni ezine ezihlukene zekhompyutha ukuze kuqinisekiswe ukuthi usayizi wemeshi akuphazamisi ukulingisa.Endabeni yepayipi le-torsion engu-45 °, inani lamayunithi anosayizi weyunithi 1.75 mm ngu-249,033, inani lamayunithi anosayizi weyunithi 2 mm ngu-307,969, inani lamayunithi anosayizi weyunithi 2.25 mm ngu-421,406, kanye nenani lamayunithi. ngosayizi weyunithi 2 .5 mm 564 940 ngokulandelana.Ngaphezu kwalokho, esibonelweni sepayipi elisontekile elingu-90°, inani lezinto ezinosayizi we-elementi engu-1.75 mm lingu-245,531, inani lezinto ezinosayizi we-elementi engu-2 mm ngu-311,584, inani lezinto ezinosayizi we-elementi engu-2.25 mm ngu-2.25 mm. 422,708, kanye nenani lama-elementi anosayizi we-elementi engu-2.5 mm ngokulandelana kwawo ngu-573,826.Ukunemba kokufundwa kwendawo eshisayo efana ne-(Tout, htc, ne-Nuavg) kuyanda njengoba inani lezinto lincipha.Ngesikhathi esifanayo, ukunemba kwamanani we-coefficient yokungqubuzana nokwehla kwengcindezi kubonise ukuziphatha okuhluke ngokuphelele (Fig. 2).Igridi (2) isetshenziswe njengendawo yegridi eyinhloko ukuze kuhlolwe izici ze-thermal-hydraulic esimweni esifanisiwe.
Ukuhlola ukudluliswa kokushisa nokusebenza kokwehla kwengcindezi ngaphandle kwe-mesh kusetshenziswa amashubhu e-DW asontekile ku-45° no-90°.
Imiphumela yamanje yezinombolo iqinisekisiwe ngokusebenza kokudlulisa ukushisa kanye ne-coefficient yokungqubuzana kusetshenziswa ukuhlobana kwe-empirical okwaziwayo kanye nezibalo ezifana ne-Dittus-Belter, Petukhov, Gnelinsky, Notter-Rouse kanye ne-Blasius.Ukuqhathanisa kwenziwe ngaphansi kwesimo esithi 7000≤Re≤17000.Ngokusho komkhiwane.3, isilinganiso namaphutha aphezulu phakathi kwemiphumela yokulingisa kanye ne-equation yokudlulisa ukushisa kungu-4.050 no-5.490% (Dittus-Belter), 9.736 kanye no-11.33% (Petukhov), 4.007 no-7.483% (Gnelinsky), kanye no-3.883% no-4.93% (4.93%) Nott-Belter).Rose).Kulokhu, amaphutha aphakathi nendawo phakathi kwemiphumela yokulingisa kanye ne-equation coefficient equation yi-7.346% no-8.039% (Blasius) kanye no-8.117% no-9.002% (Petukhov), ngokulandelanayo.
Ukudluliswa kokushisa kanye nezakhiwo ze-hydrodynamic ze-DW ezinombolweni ezihlukene ze-Reynolds kusetshenziswa izibalo zezinombolo nokuhlotshaniswa kwe-empirical.
Lesi sigaba sidingida izakhiwo ezishisayo ze-non-covalent (LNP-SDBS) kanye ne-covalent (LNP-COOH) yama-nanofluid aqueous kumafrakshini amathathu enqwaba ahlukene kanye nezinombolo ze-Reynolds njengama-avareji ahlobene ne-base fluid (DW).Amajiyometri amabili okushintshanisa ukushisa kwebhande elihlanganisiwe (i-helix angle 45° kanye no-90°) kuxoxiswana ngayo ku-7000 ≤ Re ≤ 17000. Emkhiwaneni.4 ibonisa izinga lokushisa elimaphakathi ekuphumeni kwe-nanofluid ku-base fluid (DW) (\(\frac{{{T}_{out}}_{NFs}}{{T}_{out}_{ DW } } \) ) kokuthi (0.025% wt., 0.05% wt. kanye no-0.1% wt.).(\(\frac{{{T}_{out}}_{NFs}}{{{T}_{out}_{DW}}\)) ihlale ingaphansi kuka-1, okusho ukuthi izinga lokushisa lokuphumayo ayiyona i-covalent (VNP-SDBS) futhi i-covalent (VNP-COOH) nanofluids ingaphansi kwezinga lokushisa lapho kuphuma khona uketshezi oluyisisekelo.Ukwehliswa okuphansi nokuphezulu kube ngu-0.1 wt%-COOH@GNPs kanye no-0.1 wt%-SDBS@GNPs, ngokulandelanayo.Lesi simo sibangelwa ukwanda kwenombolo ye-Reynolds engxenyeni yenqwaba engashintshi, okuholela ekushintsheni kwezakhiwo ze-nanofluid (okungukuthi, ukuminyana kanye ne-viscosity eguquguqukayo).
Izibalo 5 kanye ne-6 zibonisa izici zokudlulisa ukushisa ezimaphakathi ze-nanofluid kuya ku-base fluid (DW) ku-(0.025 wt.%, 0.05 wt.% kanye no-0.1 wt.%).Izakhiwo ezimaphakathi zokudlulisa ukushisa zihlala zikhulu kuno-1, okusho ukuthi izici zokudlulisa ukushisa ze-non-covalent (LNP-SDBS) kanye ne-covalent (LNP-COOH) nanofluids ziyathuthukiswa uma kuqhathaniswa noketshezi oluyisisekelo.0.1 wt%-COOH@GNPs kanye no-0.1 wt%-SDBS@GNPs bathole inzuzo ephansi nephezulu kakhulu, ngokulandelanayo.Lapho inombolo ye-Reynolds ikhula ngenxa yokuxutshwa okukhulu koketshezi kanye nesiyaluyalu kupayipi 1, ukusebenza kokudlulisa ukushisa kuba ngcono.Uketshezi oludlula izikhala ezincane lufinyelela isivinini esikhulu, okuholela emngceleni wesivinini/wokushisa, okwandisa izinga lokudlulisa ukushisa.Ukwengeza ama-nanoparticles amaningi ku-base fluid kungaba nemiphumela emihle nemibi.Imiphumela ezuzisayo ihlanganisa ukungqubuzana kwe-nanoparticle okwandisiwe, izidingo zokwenziwa koketshezi ezishisayo, kanye nokudluliswa kokushisa okuthuthukisiwe.
I-coefficient yokudlulisa ukushisa kwe-nanofluid kuya kuketshezi oluyisisekelo kuye ngenombolo ye-Reynolds yamashubhu angu-45° no-90°.
Ngesikhathi esifanayo, umphumela omubi ukwanda kwe-viscosity eguquguqukayo ye-nanofluid, okunciphisa ukuhamba kwe-nanofluid, ngaleyo ndlela kunciphise inombolo ye-Nusselt evamile (Nuavg).Ukwenyuka kwe-thermal conductivity ye-nanofluids (ZNP-SDBS@DW) kanye (ZNP-COOH@DW) kufanele kube ngenxa yokunyakaza kwe-Brownian kanye ne-microconvection ye-graphene nanoparticles emisiwe ku-DW37.I-thermal conductivity ye-nanofluid (ZNP-COOH@DV) iphakeme kunaleyo ye-nanofluid (ZNP-SDBS@DV) kanye namanzi acwengiwe.Ukwengeza ama-nanomaterials engeziwe ku-base fluid kwandisa ukusebenza kwawo okushisayo (Ithebula 1)38.
Umfanekiso wesi-7 ubonisa isilinganiso se-coefficient yokungqubuzana kwama-nanofluid anoketshezi oluyisisekelo (DW) (f(NFs)/f(DW)) ngamaphesenti obunzima (0.025%, 0.05% kanye no-0.1%).I-coefficient ye-friction evamile ihlale ingu-≈1, okusho ukuthi i-non-covalent (GNF-SDBS@DW) ne-covalent (GNF-COOH@DW) nanofluids ane-coefficient yokungqubuzana okufanayo noketshezi oluyisisekelo.Isishintshi sokushisa esinesikhala esincane sidala ukuvinjelwa kokugeleza okwengeziwe futhi sandise ukungqubuzana kokugeleza1.Ngokuyisisekelo, i-coefficient of friction inyuka kancane ngokwanda kwengxenye enkulu ye-nanofluid.Ukulahlekelwa okuphezulu kokungqubuzana kubangelwa ukwanda kwe-viscosity eguquguqukayo ye-nanofluid kanye nokwanda kwengcindezi ye-shear endaweni ngephesenti elikhulu le-nanographene kuketshezi oluyisisekelo.Ithebula (1) libonisa ukuthi i-dynamic viscosity ye-nanofluid (ZNP-SDBS@DV) iphakeme kunaleyo ye-nanofluid (ZNP-COOH@DV) ngephesenti lesisindo esifanayo, elihlotshaniswa nokwengezwa kwemiphumela yangaphandle.ama-agent asebenzayo ku-nanofluid engeyona i-covalent.
Emkhiwaneni.I-8 ibonisa i-nanofluid uma iqhathaniswa ne-base fluid (DW) (\(\frac{{\Delta P}_{NFs}}{{\Delta P}_{DW}}\)) ngo-(0.025%, 0.05% kanye no-0.1% ).I-non-covalent (GNPs-SDBS@DW) i-nanofluid ibonise ukulahlekelwa kwengcindezi ephakeme okumaphakathi, futhi ngokunyuka kwamaphesenti amakhulu kuya ku-2.04% ku-0.025% wt., 2.46% ku-0.05% wt.kanye no-3.44% ngo-0.1% wt.ngokukhuliswa kwekesi (i-helix angle 45° kanye no-90°).Phakathi naleso sikhathi, i-nanofluid (GNPs-COOH@DW) ibonise ukulahlekelwa kwengcindezi emaphakathi, ikhuphuka isuka ku-1.31% ku-0.025% wt.kuze kufike ku-1.65% ku-0.05% wt.Isilinganiso sokulahlekelwa kwengcindezi engu-0.05 wt.%-COOH@NP kanye no-0.1 wt.%-COOH@NP ngu-1.65%.Njengoba kubonakala, ukwehla kwengcindezi kuyanda ngokukhula kwenombolo ka-Re kuzo zonke izimo.Ukwehla kwengcindezi eyengeziwe kumanani aphezulu we-Re kuboniswa ukuncika okuqondile ekugelezeni kwevolumu.Ngakho-ke, inombolo ephakeme ye-Re ku-tube iholela ekwehleni kwengcindezi ephakeme, okudinga ukwanda kwamandla epompo39,40.Ukwengeza, ukulahlekelwa kwengcindezi kuphezulu ngenxa yokuqina okuphezulu kwama-eddies kanye nesiyaluyalu esidalwa indawo enkulu engaphezulu, okwandisa ukusebenzisana kwengcindezi namandla e-inetia kungqimba lomngcele1.
Ngokuvamile, i-performance evaluation criteria (PEC) ye-non-covalent (VNP-SDBS@DW) kanye ne-covalent (VNP-COOH@DW) nanofluids iboniswa kumakhiwane.9. I-Nanofluid (ZNP-SDBS@DV) ibonise amanani e-PEC aphezulu kune-(ZNP-COOH@DV) kuzo zombili izimo (i-helix angle 45° kanye no-90°) futhi yathuthukiswa ngokukhuphula ingxenye enkulu, isibonelo, u-0.025 wt.%.ngu-1.17, 0.05 wt.% ngu-1.19 kanye no-0.1 wt.% ngu-1.26.Ngaleso sikhathi, amanani e-PEC asebenzisa ama-nanofluids (GNPs-COOH@DW) ayengu-1.02 ku-0.025 wt%, 1.05 ngo-0.05 wt%, 1.05 ngo-0.1 wt%.kuzo zombili izimo (i-helix angle 45 ° no-90 °).1.02.Njengomthetho, ngokunyuka kwenombolo ye-Reynolds, ukusebenza kahle kwe-thermal-hydraulic kuncipha kakhulu.Njengoba inombolo ye-Reynolds ikhula, ukwehla kwe-coefficient ye-thermal-hydraulic ukusebenza kahle kuhlotshaniswa ngokuhlelekile nokwanda kwe-(NuNFs/NuDW) kanye nokwehla ku-(fNFs/fDW).
Izici ze-Hydrothermal zama-nanofluid ngokuphathelene noketshezi oluyisisekelo kuye ngezinombolo ze-Reynolds zamashubhu anama-engeli angu-45° no-90°.
Lesi sigaba sidingida izici ezishisayo zamanzi (DW), i-non-covalent (VNP-SDBS@DW), kanye ne-covalent (VNP-COOH@DW) nanofluids ekugxilweni kwesisindo okuthathu okuhlukene kanye nezinombolo ze-Reynolds.Amajiyomethri amabili ahlanganisiwe wokushisa amabhande aye acatshangelwa kububanzi obungu-7000 ≤ Re ≤ 17000 ngokuphathelene namapayipi avamile (ama-engeli we-helix 45° kanye no-90°) ukuze kuhlolwe ukusebenza okumaphakathi kwe-thermal-hydraulic.Emkhiwaneni.I-10 ibonisa izinga lokushisa lamanzi nama-nanofluid endaweni yokuphuma njengesilinganiso sokusebenzisa (i-engeli ye-helix engu-45° no-90°) yepayipi elivamile (\(\frac{{{T}_{out}}_{Twisted}}{{ {T} _{out}_{Okuvamile}}\)).I-Non-covalent (GNP-SDBS@DW) kanye ne-covalent (GNP-COOH@DW) ama-nanofluids anezingxenye ezintathu zesisindo ezihlukene ezifana no-0.025 wt%, 0.05 wt% kanye no-0.1 wt%.Njengoba kuboniswe emkhiwaneni.11, inani elimaphakathi lezinga lokushisa eliphumayo (\(\frac{{{T}_{out}}_{Twisted}}{{{T}_{out}}_{Plain}}\)) > 1, okubonisa ukuthi (i-engeli engu-45° kanye ne-90° ye-helix) izinga lokushisa ekuphumeni kwesishintshi sokushisa libaluleke kakhulu kunepayipi elivamile, ngenxa yokuqina okukhulu kwesiyaluyalu kanye nokuxutshwa okungcono koketshezi.Ngaphezu kwalokho, izinga lokushisa lapho kuphuma khona i-DW, i-non-covalent ne-covalent nanofluids lehla ngenani elikhulayo le-Reynolds.I-base fluid (DW) inezinga lokushisa eliphakeme kakhulu le-outlet.Ngaleso sikhathi, inani eliphansi libhekisela ku-0.1 wt%-SDBS@GNPs.I-Non-covalent (GNPs-SDBS@DW) ama-nanofluids abonise izinga lokushisa eliphansi eliphakathi nendawo eliqhathaniswa ne-covalent (GNPs-COOH@DW) nanofluids.Njengoba i-tape esontekile yenza insimu yokugeleza ixubene kakhulu, ukushisa okuseduze kodonga kungadlula kalula oketshezini, okwandisa izinga lokushisa jikelele.Isilinganiso esiphansi se-twist-to-tape siholela ekungeneni okungcono futhi ngaleyo ndlela ukudlulisa ukushisa okungcono.Ngakolunye uhlangothi, kungabonakala ukuthi i-tape egoqiwe igcina izinga lokushisa eliphansi ngokumelene nodonga, okwandisa i-Nuavg.Okufakwayo kwe-tape esontekile, inani eliphakeme le-Nuavg libonisa ukudluliswa kokushisa kwe-convective okuthuthukisiwe ngaphakathi kwe-tube22.Ngenxa yokwanda kwendlela yokugeleza kanye nokuxuba okungeziwe kanye nesiyaluyalu, isikhathi sokuhlala siyakhula, okuholela ekwandeni kwezinga lokushisa loketshezi ekuphumeni41.
I-Reynolds izinombolo zama-nanofluid ahlukahlukene uma kuqhathaniswa nezinga lokushisa lokuphuma kwamashubhu avamile (ama-engeli angu-45° no-90° we-helix).
Ama-coefficients okudlulisa ukushisa (45° kanye ne-90° i-engeli ye-helix) ngokuqhathanisa nezinombolo ze-Reynolds zama-nanofluid ahlukahlukene uma kuqhathaniswa namashubhu avamile.
Indlela eyinhloko yokudlulisa ukushisa kwe-tape ehlanganisiwe ethuthukisiwe ingokulandelayo: 1. Ukunciphisa ububanzi be-hydraulic weshubhu lokushintshanisa ukushisa kuholela ekwandeni kwesivinini sokugeleza nokugoba, okubuye kukhulise ukucindezeleka kwe-shear odongeni futhi kukhuthaze ukunyakaza kwesibili.2. Ngenxa yokuvinjelwa kwe-tape ejikelezayo, ijubane odongeni lwamapayipi landa, futhi ubukhulu bongqimba bomngcele buyancipha.3. Ukugeleza okuvunguzayo ngemuva kwebhande elisontekile kuholela ekwandeni kwejubane.4. Ama-vortice adaliwe athuthukisa ukuhlangana koketshezi phakathi kwezifunda ezimaphakathi neziseduze nezindonga zokugeleza42.Emkhiwaneni.11 kanye nomkhiwane.I-12 ibonisa izici zokudlulisa ukushisa kwe-DW nama-nanofluid, isibonelo (i-coefficient yokudlulisa ukushisa nesilinganiso senombolo ye-Nusselt) njengezilinganiso ezisetshenziswa amashubhu okufaka itheyiphu esontekile uma kuqhathaniswa namashubhu avamile.I-Non-covalent (GNP-SDBS@DW) kanye ne-covalent (GNP-COOH@DW) ama-nanofluids anezingxenye ezintathu zesisindo ezihlukene ezifana no-0.025 wt%, 0.05 wt% kanye no-0.1 wt%.Kuzo zombili izishintshi zokushisa (i-engeli engu-45° kanye ne-90° ye-helix) isilinganiso sokusebenza sokudlulisa ukushisa singu->1, okubonisa ukuthuthuka kwe-coefficient yokudlulisa ukushisa kanye nesilinganiso senombolo ye-Nusselt enamashubhu ahlanganisiwe uma kuqhathaniswa namashubhu avamile.I-Non-covalent (GNPs-SDBS@DW) ama-nanofluids abonise ukuthuthukiswa kokudlulisa ukushisa okumaphakathi okuphezulu kune-covalent (GNPs-COOH@DW) nanofluids.Ku-Re = 900, ukuthuthukiswa okungu-0.1 wt% ekusebenzeni kokudlulisa ukushisa -SDBS@GNPs kuma-exchanger okushisa amabili (i-engeli engu-45° kanye ne-90° ye-helix) kwakuphakeme kakhulu ngenani elingu-1.90.Lokhu kusho ukuthi umphumela we-TP ofanayo ubaluleke kakhulu emazingeni aphansi oketshezi (inombolo ye-Reynolds)43 kanye nokwanda kokuqina kwesiyaluyalu.Ngenxa yokwethulwa kwama-vortices amaningi, i-coefficient yokudlulisa ukushisa kanye nesilinganiso senani le-Nusselt lamashubhu e-TT liphakeme kunamashubhu avamile, okuholela kungqimba oluncane lomngcele.Ingabe ukuba khona kwe-HP kwandisa ukushuba kwesiyaluyalu, ukuxubana kokugeleza koketshezi olusebenzayo kanye nokudluliselwa kokushisa okuthuthukisiwe uma kuqhathaniswa namapayipi ayisisekelo (ngaphandle kokufaka itheyiphu esontekile)21.
Inombolo emaphakathi ye-Nusselt (i-engeli ye-helix engu-45° no-90°) uma iqhathaniswa nenombolo ye-Reynolds yama-nanofluid ahlukahlukene uma kuqhathaniswa namashubhu avamile.
Amanani 13 kanye no-14 abonisa isilinganiso se-coefficient of friction (\(\frac{{f}_{Twisted}}{{f}_{Plain}}\)) kanye nokulahlekelwa kwengcindezi (\(\frac{{\Delta P} _ {Twisted}}{{\Delta P}_{Plain}}\}} cishe u-45° no-90° wamapayipi avamile asebenzisa i-DW nanofluids, (GNPs-SDBS@DW) kanye (GNPs-COOH@DW) isishintshi se-ion siqukethe ( 0.025 wt %, 0.05 wt % kanye no-0.1 wt %). { {f}_{Plain} }\)) nokulahlekelwa yingcindezi (\(\frac{{ \Delta P}_{Twisted}}{{\Delta P }_{Plain}}\}) kuncipha. izimo, i-coefficient yokungqubuzana nokulahlekelwa kwengcindezi kuphezulu ezinombolweni eziphansi ze-Reynolds Isilinganiso se-coefficient yokungqubuzana nokulahlekelwa kwengcindezi kuphakathi kuka-3.78 no-3.12 Isilinganiso se-coefficient yokungqubuzana nokulahlekelwa kwengcindezi kubonisa ukuthi (45° helix i-engeli kanye no-90°) isishintshi sokushisa sibiza ngokuphindwe kathathu kunamapayipi avamile.Ngaphezu kwalokho, lapho uketshezi olusebenzayo lugeleza ngesivinini esiphezulu, i-coefficient of friction iyancipha. Inkinga iphakama ngoba njengoba inombolo ye-Reynolds ikhula, ukujiya kwesendlalelo somngcele kunciphisa, okuholela ekunciphiseni komphumela we-viscosity eguquguqukayo endaweni ethintekile, ukwehla kwe-velocity gradients nokucindezeleka kwe-shear futhi, ngenxa yalokho, ukwehla kwe-coefficient of friction21.Umphumela wokuvinjwa othuthukisiwe ngenxa yokuba khona kwe-TT kanye nokukhuphuka kwe-swirl kuphumela ekulahlekelweni kwengcindezi ephakeme kakhulu yamapayipi e-TT ahlukahlukene kunamapayipi ayisisekelo.Ngaphezu kwalokho, kokubili ipayipi yesisekelo kanye nepayipi ye-TT, kungabonakala ukuthi ukwehla kwengcindezi kuyanda ngesivinini se-fluid esebenzayo43.
I-coefficient of friction (45° kanye ne-90° helix angle) iqhathaniswa nenombolo ye-Reynolds yama-nanofluid ahlukahlukene uma kuqhathaniswa namashubhu avamile.
Ukuncipha kwengcindezi (i-engeli engu-45° kanye ne-90° ye-helix) njengomsebenzi wenombolo ye-Reynolds yama-nanofluid ahlukahlukene ahlobene neshubhu elivamile.
Kafushane, Umfanekiso 15 ubonisa indlela yokuhlola ukusebenza (PEC) yezishintshi zokushisa ezinama-engeli angu-45° no-90° uma kuqhathaniswa namashubhu angenalutho (\(\frac{{PEC}_{Twisted}}{{PEC}_{Plain}}}) \ ) ) ku-(0.025 wt.%, 0.05 wt.% kanye no-0.1 wt.%) usebenzisa i-DV, (VNP-SDBS@DV) kanye ne-covalent (VNP-COOH@DV) nanofluids.Inani (\(\frac{{PEC}_{Twisted}}{{PEC}_{Plain}}\)) > 1 kuzo zombili izimo (45° kanye ne-90° i-engeli ye-helix) kusishintshi sokushisa.Ngaphezu kwalokho, (\(\frac{{PEC}_{Twisted}}{{PEC}_{Plain}}\)) ifinyelela inani layo elingcono kakhulu ku-Re = 11,000.Isishintshi sokushisa esingu-90° sibonisa ukunyuka okuncane kokuthi (\ (\frac{{PEC}_{Twisted}}{{PEC}_{Plain}}\)) uma kuqhathaniswa nesishintshi sokushisa esingu-45°., E-Re = 11,000 0.1 wt%-GNPs@SDBS imelela amanani aphezulu (\(\frac{{PEC}_{Twisted}}{{PEC}_{Plain}}}\)), isb. 1.25 45° ikhona lesishintshi sokushisa kanye no-1.27 kokushintshisana kokushisa kwekhona elingu-90°.Inkulu kuneyodwa kuwo wonke amaphesenti wengxenyana enkulu, okubonisa ukuthi amapayipi anokufakwa kwe-tape esontekile aphakeme kunamapayipi avamile.Ngokuphawulekayo, ukudluliswa kokushisa okuthuthukisiwe okuhlinzekwa ukufakwa kwe-tape kubangele ukwanda okuphawulekayo kokulahlekelwa kokungqubuzana22.
Inqubo yokusebenza kahle yenombolo ye-Reynolds yama-nanofluid ahlukahlukene ngokuhlobene namashubhu avamile (i-engeli engu-45° kanye ne-90° ye-helix).
I-Appendix A ibonisa imigqa yokushintshashintsha kokushisa okungu-45° no-90° ku-Re = 7000 kusetshenziswa i-DW, 0.1 wt%-GNP-SDBS@DW kanye no-0.1 wt%-GNP-COOH@DW.Imigqa yokugeleza endizeni ephambanayo iyisici esihlaba umxhwele kakhulu somthelela wokufakwa kweribhoni elisontekile ekugelezeni okukhulu.Ukusetshenziswa kwezishintshi zokushisa okungu-45° no-90° kubonisa ukuthi isivinini endaweni eseduze nodonga sicishe sifane.Phakathi naleso sikhathi, iSithasiselo B sikhombisa amakhonco esivinini angu-45° kanye no-90° ashintshisana ngokushisa ku-Re = 7000 kusetshenziswa i-DW, 0.1 wt%-GNP-SDBS@DW kanye no-0.1 wt%-GNP-COOH@DW.Amalophu esivinini asezindaweni ezintathu ezihlukene (izingcezu), isibonelo, i-Plain-1 (P1 = −30mm), i-Plain-4 (P4 = 60mm) ne-Plain-7 (P7 = 150mm).Isivinini sokugeleza eduze kodonga lwamapayipi siphansi kakhulu futhi isivinini soketshezi siyakhuphuka siye phakathi nendawo yepayipi.Ngaphezu kwalokho, lapho udlula emgudwini womoya, indawo yama-velocities aphansi eduze nodonga iyanda.Lokhu kungenxa yokukhula kwesendlalelo somngcele we-hydrodynamic, okwandisa ukushuba kwesifunda esinesivinini esiphansi eduze kodonga.Ngaphezu kwalokho, ukwandisa inombolo ye-Reynolds kukhulisa izinga lejubane lilonke kuzo zonke izingxenye eziphambanayo, ngaleyo ndlela kunciphisa ukushuba kwesifunda sesivinini esiphansi esiteshini39.
Ama-graphene nanosheet asebenza ngokuhlanganyela nangokungahlangani ahlolwe ekufakweni kwetheyiphu esontekile ngama-engeli we-helix angu-45° no-90°.Isishintshi sokushisa sixazululwa ngezinombolo kusetshenziswa imodeli ye-SST k-omega turbulence at 7000 ≤ Re ≤ 17000. Izici ze-thermophysical zibalwa kokuthi Tin = 308 K. Ngesikhathi esifanayo shisisa udonga lweshubhu elisontekile ngezinga lokushisa elingashintshi elingu-330 K. COOH@DV) ihlanjululwe ngamanani amathathu esisindo, isibonelo (0.025 wt.%, 0.05 wt.% kanye no-0.1 wt.%).Ucwaningo lwamanje lucabangele izici eziyisithupha eziyinhloko: izinga lokushisa le-outlet, i-coefficient yokudlulisa ukushisa, inombolo ye-Nusselt emaphakathi, i-coefficient of friction, ukulahlekelwa kwengcindezi, kanye nemibandela yokuhlola ukusebenza.Nansi imiphumela eyinhloko:
Izinga lokushisa elimaphakathi (\({{T}_{out}}_{Nanofluids}\)/\({{T}_{out}}_{Basefluid}\)) lihlala lingaphansi kuka-1, okusho ukuthi Ukungasakazeki Izinga lokushisa le-valence (ZNP-SDBS@DV) kanye ne-covalent (ZNP-COOH@DV) nanofluids liphansi kunalelo loketshezi oluyisisekelo.Ngaleso sikhathi, izinga lokushisa elimaphakathi (\({{T}_{out}}_{Twisted}\)/\({{T}_{out}}_{Plain}\)) inani > 1, elibonisa iqiniso lokuthi (i-engeli engu-45° kanye ne-90° ye-helix) izinga lokushisa lokuphuma liphakeme kunamashubhu avamile.
Kuzo zombili izimo, amanani amaphakathi ezindawo zokudlulisa ukushisa (i-nanofluid/base fluid) kanye (ishubhu elisontekile/ishubhu elivamile) ahlala ebonisa >1.Ama-non-covalent (GNPs-SDBS@DW) ama-nanofluids abonise ukukhuphuka okumaphakathi okuphezulu kokudluliswa kokushisa, okuhambisana nama-nanofluids ama-covalent (GNPs-COOH@DW).
Isilinganiso se-friction coefficient (\({f}_{Nanofluids}/{f}_{Basefluid}\)) ye-non-covalent (VNP-SDBS@DW) kanye ne-covalent (VNP-COOH@DW) nanofluids ihlezi ithi ≈1 .friction of non-covalent (ZNP-SDBS@DV) kanye ne-covalent (ZNP-COOH@DV) nanofluids (\({f}_{Twisted}/{f}_{Plain}\)) njalo > 3.
Kuzo zombili izimo (i-engeli engu-45° kanye ne-90° ye-helix), ama-nanofluids (GNPs-SDBS@DW) abonise phezulu (\({\Delta P}_{Nanofluids}/{\Delta P}_{Basefluid}\)) 0.025 wt .% ngokungu-2.04%, 0.05 wt.% kokungu-2.46% no-0.1 wt.% ku-3.44%.Ngaleso sikhathi, (GNPs-COOH@DW) ama-nanofluid abonise ngaphansi (\({\Delta P}_{Nanofluids}/{\Delta P}_{Basefluid}\)) ukusuka ku-1.31% kokungu-0.025 wt.% ukuya ku-1.65% kungu-0.05 % ngesisindo.Ngaphezu kwalokho, isilinganiso sokulahlekelwa kwengcindezi (\({\Delta P}_{Twisted}/{\Delta P}_{Plain}\) ye-non-covalent (GNPs-SDBS@DW) kanye ne-covalent (GNPs-COOH@DW) ))) ama-nanofluid njalo >3.
Kuzo zombili izimo (ama-engeli angu-45° no-90° we-helix), ama-nanofluids (GNPs-SDBS@DW) abonise inani eliphezulu (\({PEC}_{Nanofluids}/{PEC} _{Basefluid}\)) @DW ivelu) , isb 0.025 wt.% – 1.17, 0.05 wt.% – 1.19, 0.1 wt.% – 1.26.Kulesi simo, amanani e-(\({PEC}_{Nanofluids}/{PEC}_{Basefluid}\)) esebenzisa (GNPs-COOH@DW) nanofluids angu-1.02 ku-0.025 wt.%, 1.05 ku-0 awu ,05w.% kanye no-1.02 ngu-0.1% ngesisindo.Ngaphezu kwalokho, ku-Re = 11,000, 0.1 wt%-GNPs@SDBS ibonise amanani aphezulu (\({PEC}_{Twisted}/{PEC}_{Plain}\)), njengo-1.25 nge-engeli ye-helix engu-45° kanye ne-engeli engu-90° helix engu-1.27.
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Isikhathi sokuthumela: Mar-17-2023