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304 10 * 1mm Insimbi engenasici ebhijelwe ityhubhu eTshayina
Ubungakanani: 3/4 intshi, 1/2 intshi, 1 intshi, 3 intshi, 2 intshi
Ubude bombhobho weyunithi: imitha ezi-6
IBanga leNsimbi: 201, 304 NO-316
IBakala: 201, 202, 304, 316, 304L, 316 L,
Material: STAINLESS Steel
Imeko: Entsha
Ikhoyili yetyhubhu yentsimbi engenaStainless
Ubungakanani: 3/4 intshi, 1/2 intshi, 1 intshi, 3 intshi, 2 intshi
Ubude bombhobho weyunithi: imitha ezi-6
IBanga leNsimbi: 201, 304 NO-316
IBakala: 201, 202, 304, 316, 304L, 316 L,
Material: STAINLESS Steel
Imeko: Entsha
I-nanofluids ye-Covalent kunye ne-non-covalent yavavanywa kwiityhubhu ezijikelezayo ezixhotywe ngokufakela i-tape ephothiweyo kunye ne-helix angles ye-45 ° kunye ne-90 °.Inombolo ye-Reynolds yayingu-7000 ≤ Re ≤ 17000, iipropati ze-thermophysical zavavanywa kwi-308 K. Imodeli yomzimba ixazululwe ngamanani usebenzisa i-parameter turbulent viscosity model (SST k-omega turbulence).Ugxininiso (0.025 wt.%, 0.05 wt.%, kunye ne-0.1 wt.%) ye-nanofluids ZNP-SDBS@DV kunye ne-ZNP-COOH@DV zaqwalaselwa emsebenzini.Iindonga zeetyhubhu ezijijekileyo zifudumala kwiqondo lokushisa elingaguqukiyo le-330 K. Iiparamitha ezithandathu zicatshangelwe kwisifundo samanje: ukushisa kwe-outlet, i-coefficient yokudlulisa ukushisa, inani eliqhelekileyo le-Nusselt, i-coefficient of friction, i-pressure loss, kunye neendlela zokuvavanya ukusebenza.Kuzo zombini iimeko (i-helix angle ye-45 ° kunye ne-90 °), i-ZNP-SDBS@DV nanofluid ibonise iimpawu eziphezulu ze-thermal-hydraulic kune-ZNP-COOH @ DV, kwaye yanda ngokunyuka kwamaqhekeza, umzekelo, i-0.025 wt., kunye ne-0.05 wt.yi 1.19.I-% kunye ne-1.26 - 0.1 wt.%.Kuzo zombini iimeko (i-helix angle 45 ° kunye ne-90 °), amaxabiso eempawu ze-thermodynamic xa usebenzisa i-GNP-COOH @ DW yi-1.02 ye-0.025% wt., 1.05 ye-0.05% wt.kunye ne-1.02 ye-0.1% wt.
Umtshintshi wobushushu sisixhobo se-thermodynamic 1 esisetyenziselwa ukuhambisa ubushushu ngexesha lokupholisa kunye nokufudumeza imisebenzi.Iimpawu ze-thermal-hydraulic zomtshintshi wokushisa ziphucula i-coefficient yokudlulisa ukushisa kunye nokunciphisa ukuchasana kwamanzi asebenzayo.Iindlela ezininzi ziye zaphuhliswa ukuphucula ukuhanjiswa kobushushu, kubandakanywa i-turbulence enhancers2,3,4,5,6,7,8,9,10,11 kunye ne-nanofluids12,13,14,15.Ukufakwa kwe-tape ephothiweyo yenye yezona ndlela ziphumelele kakhulu zokuphucula ukutshintshwa kobushushu kutshintshiselwano lokushisa ngenxa yokulula kwayo ukugcinwa kunye neendleko eziphantsi7,16.
Kuluhlu lwezifundo zovavanyo kunye nezibalo, iipropathi ze-hydrothermal zemixube ye-nanofluids kunye nokutshintshana kobushushu kunye nokufakwa kwe-tape ephothiweyo kwafundwa.Kumsebenzi wovavanyo, iipropathi ze-hydrothermal ze-metallic nanofluids ezintathu ezahlukeneyo (Ag@DW, Fe@DW kunye ne-Cu@DW) zaphononongwa kwi-naliti ephothiweyo ye-tape (STT) i-heat exchanger17.Xa kuthelekiswa nombhobho wesiseko, i-coefficient yokudlulisa ukushisa kwe-STT iphuculwe nge-11% kunye ne-67%.I-SST layout iyona nto ibhetele kwimbono yezoqoqosho ngokubhekiselele ekusebenzeni kakuhle kunye nepharamitha α = β = 0.33.Ukongezelela, ukunyuka kwe-18.2% kwi-n kwabonwa nge-Ag @ DW, nangona ukunyuka okuphezulu kwelahleko yoxinzelelo kwakuyi-8.5 kuphela.Iinkqubo ezibonakalayo zokutshintshwa kobushushu kunye nokulahlekelwa koxinzelelo kwimibhobho egxininisekile kunye kunye nangaphandle kwee-turbulators ezidibeneyo zaphononongwa ngokusebenzisa i-turbulent flows ye-Al2O3 @ DW nanofluid kunye nokunyanzeliswa kwe-convection.I-avareji ephezulu ye-nusselt inombolo (i-Nuavg) kunye nokulahleka koxinzelelo kubonwa kwi-Re = 20,000 xa i-coil pitch = 25 mm kunye ne-Al2O3 @ DW nanofluid 1.6 vol.%.Uphononongo lwaselabhorethri luye lwenziwa uphononongo lokufuduswa kobushushu kunye neempawu zokulahleka koxinzelelo lwegraphene oxide nanofluids (GO@DW) equkuqela phantse kwityhubhu ezijikelezayo ezine-WC ezifakelwayo.Iziphumo zibonise ukuba i-0.12 vol%-GO@DW inyuse i-coefficient yokudlulisa ubushushu be-convective malunga ne-77%.Kolunye uphononongo lovavanyo, i-nanofluids (TiO2@DW) yaphuhliswa ukuba ifunde iimpawu ze-thermal-hydraulic zetyhubhu ezidityanisiweyo ezifakelwe iteyipu ephothiweyo efakelwayo20.Ubuninzi be-hydrothermal esebenzayo ye-1.258 ifunyenwe ngokusebenzisa i-0.15 vol% -TiO2 @ DW efakwe kwi-45 ° i-shaft inclined shafts kunye ne-twist factor ye-3.0.Iimodeli zokulinganisa zesigaba esinye kunye nesigaba esibini (i-hybrid) ziqwalasela ukuhamba kunye nokudluliselwa kobushushu be-CuO @ DW nanofluids kwiindawo ezahlukeneyo eziqinileyo (1-4% vol.%)21.Ukuphumelela okuphezulu kwe-thermal ye-tube efakwe kunye ne-tape enye ephothiweyo yi-2.18, kwaye ityhubhu efakwe kunye neetayipi ezimbini eziphothiweyo phantsi kweemeko ezifanayo yi-2.04 (imodeli yezigaba ezimbini, Re = 36,000 kunye ne-4 vol.%).Ukuhamba kwe-non-Newtonian turbulent nanofluid flow of carboxymethyl cellulose (CMC) kunye ne-copper oxide (CuO) kwimibhobho ephambili kunye nemibhobho efakelweyo ephothiweyo ifundwe.I-Nuavg ibonisa ukuphucuka kwe-16.1% (yombhobho oyintloko) kunye ne-60% (yombhobho odibeneyo kunye nomlinganiselo we-(H / D = 5)).Ngokubanzi, umlinganiselo osezantsi we-twist-to-ribhoni ukhokelela kwi-coefficient ephezulu yokukhuhlana.Kuphononongo lokulinga, umphumo wemibhobho ene-tape ephothiweyo (TT) kunye neekhoyili (VC) kwiipropati zokutshintshwa kobushushu kunye ne-friction coefficient yafundwa ngokusebenzisa i-CuO @ DW nanofluids.Ukusebenzisa i-0.3 vol.I-% -CuO @ DW kwi-Re = 20,000 yenza ukuba kube lula ukunyusa ukutshintshwa kobushushu kwipayipi ye-VK-2 ukuya kwixabiso eliphezulu le-44.45%.Ukongezelela, xa usebenzisa i-twisted pair cable kunye ne-coil efakwe phantsi kweemeko zomda ofanayo, i-coefficient of friction yanda ngezinto ze-1.17 kunye ne-1.19 xa kuthelekiswa ne-DW.Ngokuqhelekileyo, ukusebenza kakuhle kwe-thermal ye-nanofluids efakwe kwiikhoyili kungcono kune-nanofluids efakwe kwiintambo ezinqamlekileyo.Uphawu lwevolumetric ye-turbulent (MWCNT@DW) flow ye-nanofluid yaphononongwa ngaphakathi kwityhubhu ethe tye efakwe kwi-spiral wire.Iiparamitha zokusebenza kwe-thermal zazi> 1 kuzo zonke iimeko, ezibonisa ukuba ukudibanisa kwe-nanofluidics kunye ne-coil insert iphucula ukuhanjiswa kobushushu ngaphandle kokutya amandla ompompo.I-Abstract-Iimpawu ze-hydrothermal zombhobho we-heat-heat exchanger kunye nezinto ezahlukeneyo ezifakwe kwi-tape eguqulweyo ephothiweyo ye-V-shaped tape (VcTT) ziye zafundwa phantsi kweemeko zokuhamba okungahambi kakuhle kwe-Al2O3 + TiO2 @ DW nanofluid.Xa kuthelekiswa ne-DW kwiityhubhu ezisisiseko, i-Nuavg inokuphuculwa okuphawulekayo kwe-132% kunye ne-friction coefficient ukuya kwi-55%.Ukongeza, ukusebenza kakuhle kwamandla kwe-Al2O3 + TiO2 @ DW nanocomposite kumbhobho we-heat exchanger26 yaxutyushwa.Kuphononongo lwabo, bafumanise ukuba ukusetyenziswa kwe-Al2O3 + TiO2 @ DW kunye ne-TT kuphucule ukusebenza kakuhle kokusebenza xa kuthelekiswa ne-DW.Kwi-concentric tubular heat exchangers kunye ne-VcTT turbulators, i-Singh kunye ne-Sarkar27 isetyenzisile izixhobo zokutshintsha isigaba (PCM), i-nanofluids eyodwa / i-nanocomposite (Al2O3 @ DW kunye ne-PCM kunye ne-Al2O3 + PCM).Baxela ukuba ukuhanjiswa kobushushu kunye nokulahleka koxinzelelo kunyuka njengoko i-twist coefficient iyancipha kwaye i-nanoparticle concentration iyanda.Ubunzulu be-V-notch enkulu okanye ububanzi obuncinci bunokubonelela ngokugqithiswa kobushushu kunye nokulahleka koxinzelelo.Ukongezelela, i-graphene-platinum (i-Gr-Pt) isetyenziselwe ukuphanda ukushisa, ukungqubuzana, kunye nenqanaba lokuzala kwe-entropy ngokubanzi kwiityhubhu kunye nokufakwa kwe-2-TT28.Uphononongo lwabo lubonise ukuba ipesenti encinci ye (Gr-Pt) yanciphisa kakhulu isizukulwana sobushushu se-entropy xa kuthelekiswa nophuhliso oluphezulu lwe-entropy.I-Mixed Al2O3 @ MgO nanofluids kunye ne-conical WC ingathathwa njengomxube omhle, ekubeni umlinganiselo onyusiweyo (h / Δp) unokuphucula ukusebenza kwe-hydrothermal ye-29 ye-tube yokushisa ukushisa.Imodeli yamanani isetyenziselwa ukuvavanya ukugcinwa kwamandla kunye nokusebenza kokusingqongileyo kwabatshintshi bobushushu kunye neentlobo ezintathu ze-hybrid nanofluids (THNF) (Al2O3 + graphene + MWCNT) emisiwe kwi-DW30.Ngenxa yeNgcaciso yoVavanyo lweNtsebenzo (PEC) kuluhlu lwe-1.42-2.35, ukudibanisa i-Depressed Twisted Turbulizer Insert (DTTI) kunye (i-Al2O3 + Graphene + MWCNT) iyafuneka.
Kuze kube ngoku, ingqwalasela encinci ihlawulwe kwindima ye-covalent kunye ne-non-covalent functionalization kwi-hydrodynamic flow in thermal fluids.Injongo ethile yolu cwaningo yayikukuthelekisa iimpawu ze-thermal-hydraulic ze-nanofluids (ZNP-SDBS@DV) kunye (ZNP-COOH @ DV) kwiifakelo zetape eziphothiweyo kunye ne-helix angles ye-45 ° kunye ne-90 °.Iimpawu ze-thermophysical zilinganiswe kwi-Tin = 308 K. Kule meko, iinqununu ezintathu zobunzima zithathwe kwi-akhawunti kwinkqubo yokuthelekisa, njenge (0.025 wt.%, 0.05 wt.% kunye ne-0.1 wt.%).Ukugqithiswa koxinzelelo lwe-shear kwimodeli ye-3D ye-turbulent flow (SST k-ω) isetyenziselwa ukusombulula iimpawu ze-thermal-hydraulic.Ngaloo ndlela, olu pho nonongo lwenza igalelo elibalulekileyo ekufundweni kweempawu ezintle (ukutshintshwa kobushushu) kunye neempawu ezimbi (uxinzelelo loxinzelelo kwi-friction), ebonisa iimpawu ze-thermal-hydraulic kunye nokulungiswa kwamanzi okwenene asebenzayo kwiinkqubo zobunjineli ezinjalo.
Ubumbeko olusisiseko ngumbhobho ogudileyo (L = 900 mm kunye neDh = 20 mm).Kufakwe imilinganiselo yetape ephothiweyo (ubude = 20 mm, ubukhulu = 0.5 mm, iprofayili = 30 mm).Kule meko, ubude, ububanzi, kunye ne-stroke yeprofayili ye-spiral yayiyi-20 mm, 0.5 mm, kunye ne-30 mm, ngokulandelanayo.Iiteyiphu eziphothiweyo zithambekele kwi-45 ° kunye ne-90 °.Amanzi ahlukeneyo asebenzayo afana ne-DW, i-nanofluids engekho-covalent (GNF-SDBS @ DW) kunye ne-covalent nanofluids (GNF-COOH @ DW) kwi-Tin = 308 K, ukugxininiswa kobunzima obuthathu kunye neenombolo ezahlukeneyo zeReynolds.Iimvavanyo zenziwa ngaphakathi kwi-heat exchanger.Udonga lwangaphandle lwetyhubhu ejikelezayo lwalufudunyezwa kwiqondo lokushisa elihlala liphezulu le-330 K ukuvavanya iiparamitha zokuphucula ukuhanjiswa kobushushu.
Kwikhiwane.I-1 schematically ibonisa ityhubhu yokufaka i-tape ephothiweyo kunye neemeko zemida esebenzayo kunye nommandla we-meshed.Njengoko kukhankanyiwe ngaphambili, isantya kunye neemeko zomda woxinzelelo zisebenza kwiindawo zokungena kunye nokuphuma kwe-helix.Kwiqondo lokushisa elihlala liphezulu, imeko engabonakaliyo ibekwe eludongeni lombhobho.Ukulinganisa kwamanani kwangoku kusebenzisa isisombululo esisekelwe kuxinzelelo.Ngexesha elifanayo, inkqubo (i-ANSYS FLUENT 2020R1) isetyenziselwa ukuguqula i-equation ye-partial differential equation (PDE) ibe yinkqubo ye-algebraic equations usebenzisa indlela yomthamo ogqityiweyo (FMM).Indlela yesibini ye-SIMPLE (indlela ye-semi-implicit ye-equential pressure-dependent equations) inxulumene ne-velocity-pressure.Kufuneka kugxininiswe ukuba ukudibanisa kweentsalela zobunzima, umfutho, kunye nokulinganisa amandla kungaphantsi kwe-103 kunye ne-106, ngokulandelanayo.
p Umzobo wemimandla ebonakalayo kunye neyokubala: (a) i-helix angle 90 °, (b) i-helix angle 45 °, (c) akukho blade ye-helical.
Imodeli ye-homogeneous isetyenziselwa ukuchaza iimpawu ze-nanofluids.Ngokufaka i-nanomaterials kwi-base fluid (DW), i-fluid eqhubekayo eneempawu ezibalaseleyo ze-thermal zenziwa.Kule nkalo, iqondo lokushisa kunye nesantya se-base fluid kunye ne-nanomaterial zinexabiso elifanayo.Ngenxa yeethiyori kunye neengqikelelo ezingentla, ukuhamba okusebenzayo kwesigaba esinye kusebenza kolu phononongo.Izifundo ezininzi zibonise ukusebenza kunye nokusetyenziswa kweendlela zesigaba esisodwa sokuhamba kwe-nanofluidic31,32.
Ukuhamba kwe-nanofluids kufuneka kube yi-Newtonian turbulent, incompressible kwaye ime.Umsebenzi woxinzelelo kunye nokufudumeza kwe-viscous akubalulekanga kwesi sifundo.Ukongezelela, ubukhulu beendonga zangaphakathi nangaphandle zombhobho abuthathelwa ngqalelo.Ke ngoko, ubunzima, umfutho, kunye nokulinganisa ukugcinwa kwamandla okuchaza imodeli yobushushu kunokubonakaliswa ngolu hlobo lulandelayo:
apho \(\ overrightarrow{V}\) is the mean velocity vector, Keff = K + Kt yi-thermal conductivity esebenzayo ye-covalent kunye ne-noncovalent nanofluids, kwaye ε yireyithi yokuchithwa kwamandla.Iipropathi ezisebenzayo ze-thermophysical ze-nanofluids, kubandakanywa ukuxinana (ρ), viscosity (μ), umthamo wobushushu obukhethekileyo (Cp) kunye ne-thermal conductivity (k), eboniswe kwitheyibhile, yalinganiswa ngexesha lophononongo lovavanyo kubushushu obuyi-308 K1 xa isetyenziswa. kwezi simulators.
Ukulinganisa kwamanani okuhamba kwe-nanofluid enesiphithiphithi kwiityhubhu eziqhelekileyo kunye ne-TT zenziwa kwiinombolo ze-Reynolds 7000 ≤ Re ≤ 17000. Ezi zifaniso kunye ne-coefficients yokudlulisa ubushushu be-convective yahlaziywa kusetyenziswa imodeli ye-Mentor's κ-ω ye-turbulence ye-shear avareji yokudluliselwa koxinzelelo phezu kwe-Sturynold imodeli ye-Navier-Stokes, esetyenziswa ngokuqhelekileyo kuphando lwe-aerodynamic.Ukongezelela, imodeli isebenza ngaphandle komsebenzi wodonga kwaye ichanekile kufuphi neendonga ze-35,36.(SST) κ-ω ulawulo lweenxaki zemodeli yesiphithiphithi zezi zilandelayo:
apho \(S\) lixabiso lomlinganiselo woxinzelelo, kwaye \(y\) ngumgama kumphezulu omeleneyo.Ngeli xesha, \({\ alpha}_{1}\), \({\alpha}_{2}\), \({\beta}_{1}\), \({\beta}_{2} }\), \({\beta}^{*}\), \({\sigma}_{{k}_{1}}\), \({\sigma}_{{k}_{ 2}} }}\), \({\sigma}_{{\omega}_{1}}\) kunye \({\sigma}_{{{\omega}_{2}}\) ichaza yonke imodeli engaguqukiyo.I-F1 kunye ne-F2 yimisebenzi edibeneyo.Qaphela: F1 = 1 kumda womda, 0 ekuhambeni okuzayo.
Iiparamitha zovavanyo lokwenziwa komsebenzi zisetyenziselwa ukufunda ukuhanjiswa kobushushu obunesiphithiphithi, ukuhamba kwe-nanofluid edibeneyo kunye ne-non-covalent, umzekelo31:
Kulo mxholo, (\(\rho\)), (\(v\)), (\({D}_{h}\))) kunye (\(\mu\)) zisetyenziselwa ukuxinana, isantya solwelo. , ububanzi be-hydraulic kunye ne-viscosity eguqukayo.(\({C}_{p}\, \mathrm{u}\, k\)) - amandla athile obushushu kunye nokuhanjiswa kwe-thermal yolwelo oluhambayo.Kwakhona, (\(\dot{m}\)) ibhekisa ekuhambeni kobunzima, kwaye (\({T}_{out}-{T}_{in}\)) ibhekisa kumahluko okungena kunye nokuphuma kweqondo lobushushu.(i-NFs) ibhekisela kwi-covalent, i-nanofluids engekho-covalent, kunye (i-DW) ibhekisela kumanzi adibeneyo (i-base fluid).\({A}_{s} = \pi DL\), \({\ ngaphezulu kwe-intanethi{T}_{f}=\frac{\left({T}_{out}-{T}_{in }\right)}{2}\) kunye \({\ overline{T}_{w}=\sum \frac{{T}_{w}}{n}\).
Iimpawu ze-thermophysical ze-base fluid (DW), i-non-covalent nanofluid (GNF-SDBS @ DW), kunye ne-covalent nanofluid (GNF-COOH @ DW) zithathwe kwiincwadi ezipapashiweyo (izifundo zovavanyo), Sn = 308 K, njengoko kuboniswe kwiThebhile 134. Kwisiqhelo Kuvavanyo lokufumana i-non-covalent (GNP-SDBS@DW) i-nanofluid kunye neepesenti zobunzima ezaziwayo, iigram ezithile ze-GNP eziphambili zaqala ukulinganiswa kwibhalansi yedijithali.Umlinganiselo wobunzima be-SDBS/GNP yemveli ngu (0.5:1) ulinganiswe kwi-DW.Kule meko, i-covalent (COOH-GNP @ DW) i-nanofluids yenziwe ngokudibanisa amaqela e-carboxyl kumphezulu we-GNP usebenzisa i-acidic medium enamandla kunye ne-volume ratio (1: 3) ye-HNO3 kunye ne-H2SO4.I-nanofluids e-Covalent kunye ne-non-covalent yanqunyanyiswa kwi-DW kwiipesenti ezintathu zobunzima ezahlukeneyo ezifana ne-0.025 wt%, 0.05 wt%.kunye ne-0.1% yobuninzi.
Iimvavanyo zokuzimela ze-Mesh zenziwa kwiindawo ezine ezahlukeneyo zokubala ukuqinisekisa ukuba ubungakanani bemesh abuchaphazeli ukulinganisa.Kwimeko ye-45 ° ipayipi ye-torsion, inani leeyunithi ezinobungakanani beyunithi 1.75 mm yi-249,033, inani leeyunithi ezinobungakanani beyunithi 2 mm yi-307,969, inani leeyunithi ezinobungakanani beyunithi 2.25 mm yi-421,406, kunye nenani leeyunithi. kunye nobukhulu beyunithi 2 .5 mm 564 940 ngokulandelelanayo.Ukongezelela, kumzekelo wombhobho ojijekileyo we-90 °, inani lezinto ezinomlinganiselo we-1.75 mm yi-245,531, inani lezinto ezinomlinganiselo we-2 mm yi-311,584, inani lezinto ezinomlinganiselo we-2.25 mm ubukhulu. 422,708, kunye nenani leelementi ezinobukhulu be-2.5 mm ngokulandelelanayo yi-573,826.Ukuchaneka kokufundwa kwepropati ye-thermal efana ne-(Tout, htc, kunye ne-Nuavg) iyanda njengoko inani lezinto liyancipha.Kwangaxeshanye, ukuchaneka kwemilinganiselo ye-friction coefficient kunye nokuhla koxinzelelo kubonisa ukuziphatha okwahluke ngokupheleleyo (Fig. 2).Igridi (2) isetyenziswe njengendawo ephambili yegridi yokuvavanya iimpawu ze-thermal-hydraulic kwimeko yokulinganisa.
Ukuvavanya ukuhanjiswa kobushushu kunye nokusebenza koxinzelelo ngokuzimeleyo kwi-mesh usebenzisa izibini ze-DW tubes ezijijekileyo kwi-45 ° kunye ne-90 °.
Iziphumo zamanani zangoku ziye zaqinisekiswa ukusebenza kokufuduswa kobushushu kunye ne-friction coefficient kusetyenziswa ulungelelwaniso lweempirical olwaziwayo kunye nokulinganisa okunje ngeDittus-Belter, Petukhov, Gnelinsky, Notter-Rouse kunye neBlasius.Ukuthelekisa kwenziwa phantsi kwemeko 7000≤Re≤17000.Ngokutsho komkhiwane.I-3, i-avareji kunye neempazamo eziphezulu phakathi kweziphumo zokulinganisa kunye ne-equation yokutshintshwa kobushushu yi-4.050 kunye ne-5.490% (i-Dittus-Belter), i-9.736 kunye ne-11.33% (Petukhov), 4.007 kunye ne-7.483% (Gnelinsky), kunye ne-3.883% kunye ne-4. Nott-Belter).URose).Kule meko, i-avareji kunye neempazamo eziphezulu phakathi kweziphumo zokulinganisa kunye ne-equation coefficient equation yi-7.346% kunye ne-8.039% (Blasius) kunye ne-8.117% kunye ne-9.002% (Petukhov), ngokulandelanayo.
Ukutshintshwa kobushushu kunye neepropati ze-hydrodynamic ze-DW kwiinombolo ezahlukeneyo ze-Reynolds kusetyenziswa izibalo zamanani kunye nokulungelelaniswa kwamandla.
Eli candelo lixoxa ngeempawu ze-thermal ze-non-covalent (LNP-SDBS) kunye ne-covalent (LNP-COOH) i-nanofluids enamanzi kumacandelo amathathu ahlukeneyo obunzima kunye namanani e-Reynolds njengama-avareji ahlobene ne-base fluid (DW).Iijometri ezimbini ze-coiled belt exchangers (i-helix angle 45 ° kunye ne-90 °) zixoxwa nge-7000 ≤ Re ≤ 17000. Kwifig.I-4 ibonisa ubushushu obuphakathi ekuphumeni kwe-nanofluid kulwelo olusisiseko (DW) (\(\frac{{T}_{out}}_{NFs}}{{T}_{out}_{ DW } } \) ) e (0.025% wt., 0.05% wt. kunye ne-0.1% wt.).(\(\frac{{{T}_{out}}_{NFs}}{{{T}_{out}}_{DW}}\)) isoloko ingaphantsi kwe-1, okuthetha ukuba ubushushu bokuphuma i-non-covalent (VNP-SDBS) kunye ne-covalent (VNP-COOH) i-nanofluids ingaphantsi kobushushu ekuphumeni kolwelo olusisiseko.Olona nciphiso lusezantsi noluphezulu lube ngu-0.1 wt%-COOH@GNPs kunye ne-0.1 wt%-SDBS@GNPs, ngokulandelanayo.Esi siganeko sibangelwa ukwanda kwenani le-Reynolds kwiqhezu lobunzima obuqhubekayo, olukhokelela kutshintsho kwiipropati ze-nanofluid (oko kukuthi, ubuninzi kunye ne-viscosity eguquguqukayo).
Amanani 5 kunye ne-6 abonisa umyinge weempawu zokutshintshwa kobushushu be-nanofluid ukuya kwi-base fluid (DW) kwi- (0.025 wt.%, 0.05 wt.% kunye ne-0.1 wt.%).Iimpawu zokutshintshwa kobushushu zihlala zikhulu kune-1, oku kuthetha ukuba iipropati zokutshintshwa kobushushu be-non-covalent (LNP-SDBS) kunye ne-covalent (LNP-COOH) nanofluids ziphuculwe xa kuthelekiswa nesiseko se-fluid.I-0.1 wt%-COOH@GNPs kunye ne-0.1 wt%-SDBS@GNPs izuze eyona nzuzo iphantsi nephezulu, ngokulandelelanayo.Xa inani le-Reynolds linyuka ngenxa yokuxuba okukhulu kwamanzi kunye ne-turbulence kumbhobho we-1, ukuhanjiswa kobushushu kuphucula ukusebenza.Ulwelo oluphuma kwizikhewu ezincinci lufikelela kwisantya esiphezulu, nto leyo ekhokelela kwisantya esincinci/umda womda wobushushu, onyusa izinga lokufuduswa kobushushu.Ukongeza i-nanoparticles engaphezulu kwi-base fluid ingaba nemiphumo emihle kunye nembi.Iziphumo eziluncedo ziquka ukunyuka kwe-nanoparticle ukungqubana, iimfuno ezifanelekileyo zokuqhuba ulwelo lwe-thermal, kunye nokudluliselwa kobushushu.
I-coefficient yokudlulisa ukushisa kwe-nanofluid ukuya kwisiseko solwelo ngokuxhomekeke kwinombolo yeReynolds ye-45 ° kunye ne-90 ° yeityhubhu.
Ngelo xesha, isiphumo esibi kukunyuka kwe-viscosity eguquguqukayo ye-nanofluid, enciphisa ukuhamba kwe-nanofluid, ngaloo ndlela inciphisa inani le-nusselt eliphakathi (i-Nuavg).Ukunyuka kwe-thermal conductivity ye-nanofluids (ZNP-SDBS@DW) kunye (ZNP-COOH@DW) kufuneka ibe ngenxa yentshukumo ye-Brownian kunye ne-microconvection ye-graphene nanoparticles emisiwe kwi-DW37.I-thermal conductivity ye-nanofluid (ZNP-COOH@DV) iphezulu kune-nanofluid (ZNP-SDBS@DV) kunye namanzi adibeneyo.Ukongeza ama-nanomaterials amaninzi kwisiseko se-fluid kwandisa i-thermal conductivity (Itheyibhile 1)38.
Umzobo we-7 ubonisa i-coefficient ye-friction ye-nanofluids ene-base fluid (DW) (f (NFs) / f (DW)) kwipesenti enkulu (0.025%, 0.05% kunye ne-0.1%).Umyinge we-friction coefficient uhlala u-≈1, oku kuthetha ukuba i-non-covalent (GNF-SDBS@DW) kunye ne-covalent (GNF-COOH @ DW) i-nanofluids ine-coefficient ye-friction efanayo ne-base fluid.Isitshintshi sobushushu esinendawo encinci sidala isithintelo sokuhamba ngakumbi kwaye sonyusa ukukhuhlana1.Ngokusisiseko, i-coefficient of friction iyanda kancinci ngokunyuka kweqhekeza le-nanofluid.Ilahleko ephezulu yokukhuhlana ibangelwa kukwanda kwe-viscosity eguquguqukayo ye-nanofluid kunye nokonyuka koxinzelelo lwe-chear kumphezulu kunye nepesenti ephezulu ye-nanographene kulwelo olusisiseko.Itheyibhile (1) ibonisa ukuba i-viscosity eguquguqukayo ye-nanofluid (ZNP-SDBS@DV) iphezulu kuneye-nanofluid (ZNP-COOH @ DV) kwipesenti yobunzima obufanayo, ehambelana nokongezwa kwemiphumo yomhlaba.ii-agent ezisebenzayo kwi-nanofluid engekho-covalent.
Kwikhiwane.I-8 ibonisa i-nanofluid xa kuthelekiswa ne-base fluid (DW) (\(\frac{{\Delta P}_{NFs}}{{\Delta P}_{DW}}\)) e-(0.025%, 0.05% kunye ne-0.1% ).I-non-covalent (GNPs-SDBS @ DW) i-nanofluid ibonise i-avareji ephezulu yokulahlekelwa kwengcinezelo, kunye nokunyuka kwepesenti yobuninzi ukuya kwi-2.04% ye-0.025% wt., 2.46% ye-0.05% wt.kunye ne-3.44% ye-0.1% wt.kunye nokwandiswa kwetyala (i-helix angle 45 ° kunye ne-90 °).Okwangoku, i-nanofluid (GNPs-COOH @ DW) ibonise ukulahleka koxinzelelo oluphantsi, ukunyuka ukusuka kwi-1.31% kwi-0.025% wt.ukuya kuthi ga kwi-1.65% kwi-0.05% wt.Umyinge welahleko yoxinzelelo lwe-0.05 wt.% -COOH @ NP kunye ne-0.1 wt.% -COOH @ NP yi-1.65%.Njengoko kunokubonwa, ukuhla koxinzelelo kuyenyuka ngokunyuka kwenani le-Re kuzo zonke iimeko.Ukuhla koxinzelelo olwandisiweyo kumaxabiso aphezulu e-Re kuboniswa ngokuxhomekeka ngokuthe ngqo kumthamo wevolumu.Ngoko ke, inani eliphezulu le-Re kwi-tube likhokelela ekunciphiseni uxinzelelo oluphezulu, olufuna ukunyuka kwamandla epompo39,40.Ukongeza, ilahleko yoxinzelelo iphezulu ngenxa yokuqina okuphezulu kweeddies kunye nesiphithiphithi esiveliswa ngummandla omkhulu womphezulu, onyusa intsebenziswano yoxinzelelo kunye nemikhosi ye-inertia kumda womda1.
Ngokubanzi, indlela yokuvavanya ukusebenza (PEC) ye-non-covalent (VNP-SDBS@DW) kunye ne-covalent (VNP-COOH @ DW) i-nanofluids iboniswe kwiMifanekiso.9. I-Nanofluid (ZNP-SDBS@DV) ibonise amaxabiso aphezulu e-PEC kune (ZNP-COOH @ DV) kuzo zombini iimeko (i-helix angle 45 ° kunye ne-90 °) kwaye yaphuculwa ngokunyusa iqhezu lobunzima, umzekelo, i-0.025 wt.%.yi-1.17, 0.05 wt.% yi-1.19 kunye ne-0.1 wt.% yi-1.26.Okwangoku, amaxabiso e-PEC asebenzisa i-nanofluids (GNPs-COOH@DW) yayiyi-1.02 ye-0.025 wt%, i-1.05 ye-0.05 wt%, i-1.05 ye-0.1 wt%.kuzo zombini iimeko (i-helix angle 45 ° kunye ne-90 °).1.02.Njengomthetho, ngokunyuka kwenani leReynolds, ukusebenza kakuhle kwe-thermal-hydraulic kuncipha kakhulu.Njengoko inani le-Reynolds linyuka, ukuhla kwe-coefficient ye-thermal-hydraulic esebenzayo ihambelana ngokuchanekileyo kunye nokunyuka kwe-NuNFs / NuDW) kunye nokunciphisa (fNFs / fDW).
Iimpawu ze-Hydrothermal ze-nanofluids ngokubhekiselele kumanzi asisiseko ngokuxhomekeke kumanani e-Reynolds kwiityhubhu ezinama-45 ° kunye ne-90 °.
Eli candelo lixoxa ngeempawu ze-thermal zamanzi (i-DW), i-non-covalent (VNP-SDBS@DW), kunye ne-covalent (VNP-COOH @ DW) i-nanofluids kwiindawo ezintathu ezahlukeneyo zobunzima kunye neenombolo zeReynolds.Iijometri ezimbini ezidityanisiweyo zokutshintsha ubushushu bebhanti ziye zaqwalaselwa kuluhlu lwe-7000 ≤ Re ≤ 17000 ngokubhekiselele kwimibhobho eqhelekileyo (i-helix angles 45 ° kunye ne-90 °) ukuvavanya ukusebenza kwe-thermal-hydraulic.Kwikhiwane.I-10 ibonisa ubushushu bamanzi kunye ne-nanofluids kwi-outlet njenge-avareji usebenzisa (i-helix angle 45 ° kunye ne-90 °) kumbhobho oqhelekileyo (\(\ frac{{T}_{out}}_{Twisted}}{{ {T} _{out}_{Rhoqo}}\)).I-non-covalent (GNP-SDBS @ DW) kunye ne-covalent (GNP-COOH @ DW) i-nanofluids inamaqhezu amathathu ahlukeneyo obunzima obufana ne-0.025 wt%, 0.05 wt% kunye ne-0.1 wt%.Njengoko kubonisiwe kwifig.11, umndilili wexabiso lobushushu obuphumayo (\(\frac{{{T}_{out}}_{Twisted}}{{T}_{out}}_{Plain}}\)) > 1, ebonisa ukuba (i-45 ° kunye ne-90 ° i-angle ye-helix) iqondo lokushisa ekuphumeni kwe-heat exchanger libaluleke kakhulu kunombhobho oqhelekileyo, ngenxa yobunzima obukhulu be-turbulence kunye nokuxuba okungcono kolwelo.Ukongeza, iqondo lobushushu kwindawo yokuphuma ye-DW, i-non-covalent kunye ne-covalent nanofluids yehla ngokunyuka kwenani le-Reynolds.Ulwelo olusisiseko (DW) lunobona bushushu buphezulu bomgangatho wokuphuma.Okwangoku, ixabiso eliphantsi libhekiselele kwi-0.1 wt% -SDBS@GNPs.I-Non-covalent (GNPs-SDBS@DW) i-nanofluids ibonise ubushushu obuphakathi obusezantsi xa kuthelekiswa ne-covalent (GNPs-COOH @ DW) nanofluids.Ekubeni i-tape ephothiweyo yenza ibala lokuhamba lixutywe ngakumbi, i-flux yokushisa esondeleyo eludongeni inokudlula ngokulula kulwelo, inyuse ubushushu bubonke.Umlinganiselo osezantsi we-twist-to-tape ukhokelela ekungeneni okungcono kwaye kungoko ukuhanjiswa kobushushu obungcono.Ngakolunye uhlangothi, kunokubonwa ukuba i-tape eqengqelekayo igcina ubushushu obuphantsi eludongeni, nto leyo eyandisa i-Nuavg.Ukufakwa kwe-tape ephothiweyo, ixabiso eliphezulu le-Nuavg libonisa ukuhanjiswa kobushushu obuphuculweyo be-convective ngaphakathi kwe-tube22.Ngenxa yokunyuka kwendlela yokuhamba kunye nokuxuba okongeziweyo kunye ne-turbulence, ixesha lokuhlala liyanda, okubangelwa ukwanda kweqondo lokushisa kwamanzi kwi-outlet41.
IiReynolds amanani ee-nanofluids ezahlukeneyo ngokunxulumene nobushushu obuphumayo beetyhubhu eziqhelekileyo (45 ° kunye ne-90 ° helix angles).
I-coefficients yokudlulisa ubushushu (i-45 ° kunye ne-90 ° i-angle ye-helix) ngokuchasene namanani e-Reynolds kwii-nanofluids ezahlukeneyo xa kuthelekiswa neetyhubhu eziqhelekileyo.
Indlela ephambili yokuhanjiswa kobushushu betape ehlanganisiweyo ngolu hlobo lulandelayo: 1. Ukunciphisa i-hydraulic diameter ye-tube yokutshintshiselana kobushushu kukhokelela ekwandeni kwesantya sokuhamba kunye ne-curvature, oko kwandisa uxinzelelo lwe-shear eludongeni kunye nokukhuthaza ukunyakaza kwesibini.2. Ngenxa yokuvalelwa kwe-tape yokucima, isantya kwindonga yombhobho sanda, kwaye ubukhulu bomgca womda buyancipha.3. I-Spiral flow emva kwebhanti ejijekileyo ikhokelela ekwandeni kwesantya.4. I-vortices ebangelwayo iphucula ukuxutywa kwamanzi phakathi kwemimandla ephakathi kunye nekufuphi nodonga lwe-flow42.Kwikhiwane.11 kunye nomkhiwane.I-12 ibonisa iipropati zokushisa ukushisa kwe-DW kunye ne-nanofluids, umzekelo (i-coefficient yokudlulisa ukushisa kunye nenani eliphakathi kwe-Nusselt) njengemilinganiselo esebenzisa iityhubhu zokufaka i-tape ephothiweyo xa kuthelekiswa neetyhubhu eziqhelekileyo.I-non-covalent (GNP-SDBS @ DW) kunye ne-covalent (GNP-COOH @ DW) i-nanofluids inamaqhezu amathathu ahlukeneyo obunzima obufana ne-0.025 wt%, 0.05 wt% kunye ne-0.1 wt%.Kuzo zombini izitshintshi zobushushu (i-45 ° kunye ne-90 ° i-angle ye-helix) i-avareji yokusebenza yokudlulisa ubushushu yi->1, ebonisa ukuphuculwa kwe-coefficient yokudlulisa ubushushu kunye nenani eliqhelekileyo le-Nusselt elinemibhobho edibeneyo xa kuthelekiswa neetyhubhu eziqhelekileyo.I-Non-covalent (GNPs-SDBS@DW) i-nanofluids ibonise ukuphuculwa komyinge ophezulu wokudluliselwa kobushushu kune-covalent (GNPs-COOH@DW) nanofluids.Kwi-Re = 900, i-0.1 wt% yokuphucula ukusebenza kokutshintshwa kobushushu -SDBS @ GNPs kwi-heat exchangers ezimbini (i-45 ° kunye ne-90 ° i-angle ye-helix) yayiphezulu kunye nexabiso le-1.90.Oku kuthetha ukuba isiphumo esifanayo se-TP sibaluleke ngakumbi kwisantya esisezantsi samanzi (inombolo ye-Reynolds) i-43 kunye nokwandisa ukuqina kwe-turbulence.Ngenxa yokungeniswa kwee-vortices ezininzi, i-coefficient yokudlulisa ukushisa kunye nenani eliphakathi kwe-Nusselt yeetyhubhu ze-TT ziphezulu kuneetyhubhu eziqhelekileyo, okubangelwa ngumda omncinci womda.Ngaba ubukho be-HP bonyusa ubunzulu besiphithiphithi, ukuxutywa kokuhamba kolwelo olusebenzayo kunye nokuhanjiswa kobushushu okwandisiweyo xa kuthelekiswa nemibhobho esisiseko (ngaphandle kokufaka iteyiphu ejijekileyo)21.
I-avareji yenani le-Nusselt (i-engile ye-helix 45 ° kunye ne-90 °) ngokuchasene nenani le-Reynolds kwii-nanofluids ezahlukeneyo xa kuthelekiswa neetyhubhu eziqhelekileyo.
Amanani 13 kunye ne-14 abonisa umyinge we-coefficient of friction (\(\frac{{f}_{Twisted}}{{f}_{Plain}}\)) kunye nelahleko yoxinzelelo (\(\frac{{\Delta P} _ {Twisted}}{{\Delta P}_{Plain}}\}} malunga ne-45 ° kunye ne-90 ° kwimibhobho eqhelekileyo esebenzisa i-DW nanofluids, (GNPs-SDBS@DW) kunye (GNPs-COOH@DW) i-ion exchanger iqulethe ( 0.025 wt %, 0.05 wt % kunye 0.1 wt %). { {f}_{Plain} }\)) kunye nokulahlekelwa koxinzelelo (\(\ frac{{ \ Delta P}_{Twisted}} {{\ Delta P }_{Plain}}\}) iyancipha iimeko, i-coefficient ye-friction kunye nokulahlekelwa koxinzelelo kuphezulu kumanani aphantsi e-Reynolds I-coefficient ye-friction ephakathi kunye nokulahleka koxinzelelo phakathi kwe-3.78 kunye ne-3.12 I-coefficient ye-friction kunye nelahleko yoxinzelelo ibonisa ukuba (45 ° helix i-angle kunye ne-90 °) ixabiso lokutshintsha ubushushu liphindwe kathathu kunemibhobho eqhelekileyo.Ukongezelela, xa ulwelo olusebenzayo luhamba ngesantya esiphezulu, i-coefficient of friction iyancipha.Ingxaki ivela kuba njengoko inani le-Reynolds landa, ubukhulu bomgca womda. kuncipha, okukhokelela ekunciphiseni kwempembelelo ye-viscosity eguquguqukayo kwindawo echaphazelekayo, ukuncipha kwe-gradients yesantya kunye noxinzelelo lwe-shear kwaye, ngenxa yoko, ukuhla kwe-coefficient of friction21.Isiphumo sokuthintela esiphuculweyo ngenxa yobukho be-TT kunye nokunyuka kwe-swirl kubangela ilahleko ephezulu yoxinzelelo kwimibhobho ye-TT engafaniyo kunemibhobho yesiseko.Ukongezelela, zombini umbhobho wesiseko kunye nombhobho we-TT, kunokubonwa ukuba ukunyuka koxinzelelo kwandisa ngesantya se-fluid esebenzayo43.
I-Coefficient of friction (45 ° kunye ne-90 ° i-angle ye-helix) ngokuchasene nenani le-Reynolds kwii-nanofluids ezahlukeneyo xa kuthelekiswa neetyhubhu eziqhelekileyo.
Ukulahleka koxinzelelo (i-45 ° kunye ne-90 ° i-angle ye-helix) njengomsebenzi wenombolo ye-Reynolds kwii-nanofluids ezahlukeneyo ngokumalunga nombhobho oqhelekileyo.
Isishwankathelo, i-Figure 15 ibonisa indlela yokuvavanya ukusebenza (PEC) kutshintshiselwano lokushisa kunye ne-45 ° kunye ne-90 ° angles xa kuthelekiswa neetyhubhu ezicacileyo (\(\ frac{{PEC}_{Twisted}}{{PEC}_{Plain}}} \ ) ) kwi (0.025 wt.%, 0.05 wt.% kunye ne-0.1 wt.%) usebenzisa i-DV, (VNP-SDBS@DV) kunye ne-covalent (VNP-COOH@DV) nanofluids.Ixabiso (\(\ frac{{PEC}_{Twisted}}{{PEC}_{Plain}}\)) > 1 kuzo zombini iimeko (45 ° kunye ne-90 ° i-angle ye-helix) kwisitshintshi sobushushu.Ukongeza, (\(\ frac{{PEC}_{Twisted}}{{PEC}_{Plain}}\)) ifikelela kwixabiso layo eliphezulu kwiRe = 11,000.Ubushushu be-90 ° bubonisa ukunyuka okuncinci kwi-(\ (\ frac{{PEC}_{Twisted}} {{PEC}_{Plain}}\)) xa kuthelekiswa ne-45 ° yokushisa., E-Re = 11,000 0.1 wt%-GNPs@SDBS imele phezulu (\(\frac{{PEC}_{Twisted}}{{PEC}_{Plain}}\)) amaxabiso, umz. 1.25 ye-45 ° ikona yomtshintshisi wobushushu kunye ne-1.27 ye-90 ° kwikona yokutshintsha ubushushu.Inkulu kuneyodwa kuzo zonke iipesenti zecandelo lobunzima, elibonisa ukuba imibhobho ene-twisted tape inserts iphezulu kunemibhobho eqhelekileyo.Ngokucacileyo, ukutshintshwa kobushushu obuphuculweyo obunikezelwa ngokufakela i-tape kubangele ukwanda okukhulu kwilahleko ye-friction22.
Iikhrayitheriya zokuphumelela kwinani le-Reynolds le-nanofluids eyahlukeneyo malunga neetyhubhu eziqhelekileyo (i-45 ° kunye ne-90 ° i-angle ye-helix).
I-Appendix A ibonisa i-streamlines ye-45 ° kunye ne-90 ° i-heat exchangers kwi-Re = 7000 usebenzisa i-DW, 0.1 wt%-GNP-SDBS @ DW kunye ne-0.1 wt% -GNP-COOH@DW.I-streamlines kwinqwelomoya enqamlezileyo yiyona nto iphawulekayo yempembelelo yokufakwa kweribhoni ephothiweyo kwindlela ehamba phambili.Ukusetyenziswa kwe-45 ° kunye ne-90 ° yokutshintshiselana kobushushu kubonisa ukuba isantya kwindawo yodonga olusondeleyo luphantse lufane.Okwangoku, iSihlomelo B sibonisa iicontours zesantya se-45 ° kunye ne-90 ° abatshintshi bokushisa kwi-Re = 7000 usebenzisa i-DW, 0.1 wt%-GNP-SDBS @ DW kunye ne-0.1 wt%-GNP-COOH@DW.I-loops yesantya ikwiindawo ezintathu ezahlukeneyo (iziqwenga), umzekelo, i-Plain-1 (P1 = -30mm), i-Plain-4 (P4 = 60mm) kunye ne-Plain-7 (P7 = 150mm).Isantya sokuhamba kufuphi nodonga lombhobho sisezantsi kwaye isantya solwelo siyanda ukuya kumbindi wombhobho.Ukongeza, xa udlula kwi-air duct, indawo yesantya esisezantsi kufutshane nodonga iyanda.Oku kubangelwa ukukhula komgangatho we-hydrodynamic boundary layer, okwandisa ubukhulu bommandla we-low-velocity kufuphi nodonga.Ukongeza, ukwandisa inani le-Reynolds kwandisa inqanaba lesantya kuwo onke amacandelo anqamlezayo, ngaloo ndlela kunciphisa ubukhulu bommandla wesantya esisezantsi kwitshaneli39.
I-graphene nanosheets edibeneyo kunye ne-non-covalently functionalized ivandlakanywe kwi-tape ephothiweyo efakwe kunye ne-helix angles ye-45 ° kunye ne-90 °.Umtshintshi wokushisa uxazululwa ngamanani usebenzisa i-SST k-omega imodeli ye-turbulence kwi-7000 ≤ Re ≤ 17000. Iimpawu ze-thermophysical zibalwa kwi-Tin = 308 K. Ngexesha elifanayo ukufudumala udonga lwe-tube ephothiweyo kwiqondo lokushisa elingaguqukiyo le-330 K. COOH @ DV) yaxutywa ngezixa ezithathu zobunzima, umzekelo (0.025 wt.%, 0.05 wt.% kunye ne-0.1 wt.%).Uphononongo lwangoku luqwalasele izinto ezintandathu eziphambili: ubushushu obuphumayo, i-coefficient yokudluliselwa kobushushu, i-avareji inombolo ye-Nusselt, i-coefficient of friction, ilahleko yoxinzelelo, kunye neendlela zokuvavanya ukusebenza.Nazi iziphumo eziphambili:
Umndilili wobushushu ophumayo (\({{T}_{out}}_{Nanofluids}\)/\({{T}_{out}}_{Basefluid}\)) usoloko ungaphantsi kwe-1, okuthetha ukuba Ukungasasazeka Ubushushu bokukhutshwa kwe-valence (ZNP-SDBS@DV) kunye ne-covalent (ZNP-COOH@DV) nanofluids iphantsi kunolwelo olusisiseko.Ngeli xesha, umndilili wobushushu ophumayo (\({{T}_{out}}_{Twisted}\)/\({{T}_{out}}_{Plain}\)) ixabiso> 1, ebonisa ukuba Inyani yokuba (i-45 ° kunye ne-90 ° i-engile ye-helix) iqondo lobushushu lokuphuma liphezulu kuneityhubhu eziqhelekileyo.
Kuzo zombini iimeko, amaxabiso aphakathi kweempawu zokuhambisa ubushushu (i-nanofluid/base fluid) kunye (ityhubhu ejijekileyo/ityhubhu eqhelekileyo) ihlala ibonisa>1.I-non-covalent (i-GNPs-SDBS @ DW) i-nanofluids ibonise ukunyuka komyinge ophezulu ekugqithiseni ukushisa, okuhambelana ne-covalent (GNPs-COOH @ DW) nanofluids.
Umndilili wokukhuhlana komlinganiso (\({f}_{Nanofluids}/{f}_{Basefluid}\)) ye-non-covalent (VNP-SDBS@DW) kunye ne-covalent (VNP-COOH@DW) nanofluids isoloko ≈1 .ukukhuhlana kwe-non-covalent (ZNP-SDBS@DV) kunye ne-covalent (ZNP-COOH@DV) nanofluids (\({f}_{Twisted}/{f}_{Plain}\)) rhoqo > 3.
Kuzo zombini iimeko (i-45 ° kunye ne-90 ° i-angle ye-helix), i-nanofluids (GNPs-SDBS@DW) ibonise phezulu (\({\ Delta P}_{Nanofluids}/{\Delta P}_{Basefluid}\)) 0.025 wt .% kwi-2.04%, 0.05 wt.% kwi-2.46% kunye ne-0.1 wt.% kwi-3.44%.Ngeli xesha, (GNPs-COOH@DW) iinanofluids zibonise ngaphantsi (\({\Delta P}_{Nanofluids}/{\ Delta P}_{Basefluid}\)) ukusuka kwi-1.31% kwi-0.025 wt.% ukuya kwi-1.65% yi-0.05% yi-0.05 % ngokobunzima.Ukongeza, ilahleko yoxinzelelo oluphakathi (\({\Delta P}_{Twisted}/{\Delta P}_{Plain}\) ye-non-covalent (GNPs-SDBS@DW) kunye ne-covalent (GNPs-COOH@DW) ))) iinanofluids rhoqo >3.
Kuzo zombini iimeko (i-45 ° kunye ne-90 ° i-engile ye-helix), i-nanofluids (GNPs-SDBS@DW) ibonise ixabiso eliphezulu (\({PEC}_{Nanofluids}/{PEC} _{Basefluid}\)) @DW ixabiso) , umz.Kulo mzekelo, amaxabiso (\({PEC}_{Nanofluids}/{PEC}_{Basefluid}\)) usebenzisa (GNPs-COOH@DW) nanofluids yi-1.02 ye-0.025 wt.%, 1.05 ye-0 ,05 wt.I-% kunye ne-1.02 yi-0.1% ngobunzima.Ukongeza, kwiRe = 11,000, 0.1 wt%-GNPs@SDBS ibonise amaxabiso aphezulu (\({PEC}_{Twisted}/{PEC}_{Plain}\)), njenge-1.25 ye-45 ° i-angle ye-helix kunye ne-90 ° helix angle 1.27.
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Ixesha lokuposa: Mar-17-2023