304 bakin karfe nada tubing sinadaran bangaren, Thermodynamic bincike na covalently da wadanda ba covalently functionalized graphene nanosheets a zagaye shambura sanye take da turbulators.

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304 10 * 1mm Bakin Karfe nada bututu a cikin china

Girman: 3/4 inch, 1/2 inch, 1 inch, 3 inch, 2 inch

Tsawon Bututun Naúrar: Mita 6

Matsayin Karfe: 201, 304 DA 316

Daraja: 201, 202, 304, 316, 304L, 316 L,

Abu: KARFE KARFE

Sharadi: Sabo

An gwada nanofluids na covalent da marasa covalent a cikin bututu masu zagaye da aka sanye da murɗaɗɗen tef ɗin tare da kusurwar helix na 45° da 90°.Lambar Reynolds ita ce 7000 ≤ Re ≤ 17000, an kimanta kaddarorin thermophysical a 308 K. An warware samfurin jiki ta lambobi ta amfani da samfurin danko mai rudani mai ma'ana biyu (SST k-omega turbulence).An yi la'akari da ƙaddamarwa (0.025 wt.%, 0.05 wt.%, da 0.1 wt.%) na nanofluids ZNP-SDBS@DV da ZNP-COOH@DV a cikin aikin.Ganuwar bututun da aka murƙushe suna mai tsanani a cikin zafin jiki na 330 K. An yi la'akari da sifofi shida a cikin binciken na yanzu: zafin jiki na fitarwa, yawan zafin jiki na zafi, matsakaicin lambar Nusselt, ƙididdiga na rikici, asarar matsa lamba, da ma'auni na kimantawa.A cikin lokuta biyu (kwanguwar helix na 45 ° da 90 °), ZNP-SDBS @ DV nanofluid ya nuna halayen thermal-hydraulic mafi girma fiye da ZNP-COOH @ DV, kuma ya karu tare da ƙara yawan juzu'i, misali, 0.025 wt.da 0.05 wt.shine 1.19.% da 1.26 - 0.1 wt.A cikin lokuta biyu (kusan helix 45 ° da 90 °), ƙimar halayen thermodynamic lokacin amfani da GNP-COOH @ DW sune 1.02 don 0.025% wt., 1.05 don 0.05% wt.kuma 1.02 don 0.1% wt.
Mai musayar zafi shine na'urar thermodynamic 1 da ake amfani da ita don canja wurin zafi yayin aikin sanyaya da dumama.Abubuwan thermal-hydraulic na mai musayar zafi suna haɓaka ƙimar canjin zafi da rage juriya na ruwa mai aiki.An haɓaka hanyoyi da yawa don inganta canjin zafi, ciki har da masu haɓaka tashin hankali2,3,4,5,6,7,8,9,10,11 da nanofluids12,13,14,15.Twisted tef ɗin yana ɗaya daga cikin hanyoyin da suka fi dacewa don inganta canjin zafi a cikin masu musayar zafi saboda sauƙin kulawa da ƙananan farashi7,16.
A cikin jerin gwaje-gwajen gwaje-gwaje da ƙididdigar ƙididdiga, an yi nazarin abubuwan hydrothermal na gaurayawan nanofluids da masu musayar zafi tare da murɗaɗɗen tef ɗin.A cikin aikin gwaji, an yi nazarin kaddarorin hydrothermal na nanofluids na ƙarfe daban-daban guda uku (Ag@DW, Fe@DW da Cu@DW) a cikin wani tef ɗin murɗaɗɗen allura (STT) mai musayar zafi17.Idan aka kwatanta da bututu mai tushe, ƙimar canja wurin zafi na STT yana haɓaka da 11% da 67%.Tsarin SST shine mafi kyau daga ra'ayi na tattalin arziki dangane da inganci tare da ma'auni α = β = 0.33.Bugu da ƙari, an lura da karuwar 18.2% a cikin n tare da Ag@DW, ko da yake matsakaicin karuwa a cikin asarar matsa lamba shine kawai 8.5%.Hanyoyin jiki na canja wurin zafi da asarar matsa lamba a cikin bututu masu tattarawa tare da kuma ba tare da murƙushe turbulators an yi nazarin su ta amfani da kwararar ruwa na Al2O3@DW nanofluid tare da tilastawa.Matsakaicin matsakaicin lambar Nusselt (Nuavg) da asarar matsa lamba ana lura da su a Re = 20,000 lokacin da murhun murɗa = 25 mm da Al2O3@DW nanofluid 1.6 vol.%.Hakanan an gudanar da karatun dakin gwaje-gwaje don nazarin canjin zafi da halayen asarar matsi na graphene oxide nanofluids (GO@DW) da ke gudana ta kusan bututun madauwari tare da saka WC.Sakamakon ya nuna cewa 0.12 vol% -GO@DW ya karu da ƙimar canja wurin zafi da kusan kashi 77%.A cikin wani binciken gwaji, nanofluids (TiO2@DW) an ɓullo da su don nazarin yanayin zafi-hydraulic na bututun dimple ɗin da aka haɗa tare da murɗaɗɗen tef ɗin 20.Matsakaicin inganci na hydrothermal na 1.258 an samu ta amfani da 0.15 vol% -TiO2@DW da aka saka a cikin 45° madaidaitan igiyoyi tare da juzu'i na 3.0.Samfuran siminti guda-ɗaya da kashi biyu (matasan) suna la'akari da kwarara da canjin zafi na CuO@DW nanofluids a ɗimbin daskararru daban-daban (1-4% vol.%)21.Matsakaicin ingancin zafi na bututu da aka saka tare da tef ɗin murɗaɗi ɗaya shine 2.18, kuma bututun da aka saka tare da kaset ɗin murɗaɗɗen kaset a ƙarƙashin yanayi iri ɗaya shine 2.04 (samfurin lokaci biyu, Re = 36,000 da 4 vol.%).An yi nazarin kwararar nanofluid da ba na Newtonian ba na carboxymethyl cellulose (CMC) da jan ƙarfe oxide (CuO) a cikin manyan bututu da bututu tare da murɗaɗɗen abubuwan sakawa.Nuavg yana nuna haɓakar 16.1% (na babban bututun mai) da 60% (don bututun da aka naɗe tare da rabon (H/D = 5)).Gabaɗaya, ƙarancin karkatar-zuwa kintinkiri yana haifar da mafi girman haɗin kai.A cikin gwajin gwaji, an yi nazarin tasirin bututu tare da tef ɗin murɗaɗɗen (TT) da coils (VC) akan kaddarorin canja wurin zafi da haɗin gwiwar juzu'i ta amfani da CuO@DW nanofluids.Yin amfani da 0.3 vol.% -CuO@DW a Re = 20,000 yana ba da damar haɓaka canjin zafi a cikin bututun VK-2 zuwa matsakaicin ƙimar 44.45%.Bugu da kari, lokacin amfani da kebul na murɗaɗɗen murɗaɗɗen igiya da abin da aka saka a ƙarƙashin yanayin iyaka iri ɗaya, ƙimar juzu'i yana ƙaruwa da dalilai na 1.17 da 1.19 idan aka kwatanta da DW.Gabaɗaya, ingantaccen yanayin zafi na nanofluids da aka saka a cikin coils ya fi na nanofluids da aka saka a cikin wayoyi masu ɗaci.An yi nazarin yanayin juzu'i na tashin hankali (MWCNT@DW) kwararar nanofluid a cikin bututun kwance da aka saka a cikin waya mai karkace.Ma'auni na aikin thermal sun kasance> 1 don duk lokuta, yana nuna cewa haɗin nanofluidics tare da abin da aka saka na coil yana inganta canjin zafi ba tare da cinye ikon famfo ba.Abstract-Halayen hydrothermal na mai musayar zafi mai bututu guda biyu tare da abubuwan da aka sanya daban-daban da aka yi da gyare-gyaren tef ɗin V-Twisted Twisted (VcTT) a ƙarƙashin yanayi mai ruɗani na Al2O3 + TiO2@DW nanofluid.Idan aka kwatanta da DW a cikin bututun tushe, Nuavg yana da gagarumin ci gaba na 132% da ƙarancin juzu'i na har zuwa 55%.Bugu da ƙari, an tattauna tasirin makamashi na Al2O3+TiO2@DW nanocomposite a cikin bututu mai zafi mai zafi26.A cikin binciken su, sun gano cewa amfani da Al2O3 + TiO2@DW da TT sun inganta aikin motsa jiki idan aka kwatanta da DW.A concentric tubular zafi musayar tare da VcTT turbulators, Singh da Sarkar27 amfani da lokaci canji kayan (PCM), tarwatsa guda / nanocomposite nanofluids (Al2O3 @ DW tare da PCM da Al2O3 + PCM).Sun bayar da rahoton cewa canja wurin zafi da asarar matsa lamba yana ƙaruwa yayin da madaidaicin karkatarwa ya ragu kuma ƙaddamarwar nanoparticle yana ƙaruwa.Babban ma'aunin zurfi na V-notch ko ƙarami mai faɗi zai iya ba da mafi girman canjin zafi da asarar matsa lamba.Bugu da ƙari, an yi amfani da graphene-platinum (Gr-Pt) don bincika zafi, gogayya, da ƙimar haɓakar entropy gabaɗaya a cikin bututu tare da abubuwan 2-TT28.Nazarin su ya nuna cewa ƙaramin kaso na (Gr-Pt) ya rage haɓakar haɓakar zafin zafi idan aka kwatanta da haɓakar haɓakar haɓakar haɓakar haɓaka.Mixed Al2O3 @ MgO nanofluids da conical WC za a iya la'akari a matsayin mai kyau cakuda, tun da wani karuwa rabo (h / Δp) iya inganta da hydrothermal yi na biyu-tube zafi Exchanger 29.Ana amfani da ƙirar ƙididdiga don kimanta aikin ceton makamashi da aikin muhalli na masu musayar zafi tare da nau'ikan nanofluids masu kashi uku (THNF) (Al2O3 + graphene + MWCNT) da aka dakatar a cikin DW30.Saboda Ma'aunin Ƙididdigar Ayyukanta (PEC) a cikin kewayon 1.42-2.35, ana buƙatar haɗaɗɗen Twisted Turbulizer Insert (DTTI) da (Al2O3 + Graphene + MWCNT).
Har ya zuwa yanzu, ba a mai da hankali sosai ga rawar da ke tattare da aiki na covalent da rashin daidaituwa a cikin kwararar ruwa a cikin ruwan zafi.Maƙasudin ƙayyadaddun wannan binciken shine kwatanta halayen thermal-hydraulic nanofluids (ZNP-SDBS@DV) da (ZNP-COOH@DV) a cikin abubuwan da aka shigar da tef tare da kusurwar helix na 45 ° da 90 °.An auna ma'auni na thermophysical a Tin = 308 K. A wannan yanayin, an yi la'akari da nau'i nau'i nau'i uku a cikin tsarin kwatanta, kamar (0.025 wt.%, 0.05 wt.% da 0.1 wt.%).Ana amfani da canja wurin danniya mai ƙarfi a cikin 3D turbulent flow model (SST k-ω) don magance halayen thermal-hydraulic.Don haka, wannan binciken yana ba da gudummawa mai mahimmanci ga nazarin kyawawan kaddarorin (canja wurin zafi) da kaddarorin mara kyau (digowar matsin lamba akan juzu'i), yana nuna halayen thermal-hydraulic da haɓaka ainihin ruwa mai aiki a cikin irin wannan tsarin injiniya.
Tsarin asali shine bututu mai santsi (L = 900 mm da DH = 20 mm).Matsakaicin girman tef ɗin da aka saka (tsawon = 20 mm, kauri = 0.5 mm, bayanin martaba = 30 mm).A wannan yanayin, tsawon, nisa, da bugun jini na bayanin martaba sun kasance 20 mm, 0.5 mm, da 30 mm, bi da bi.Kaset ɗin murɗaɗɗen suna karkata zuwa 45° da 90°.Ruwan aiki iri-iri kamar DW, nanofluids marasa daidaituwa (GNF-SDBS@DW) da nanofluids na covalent (GNF-COOH@DW) a Tin = 308 K, taro daban-daban daban-daban da lambobi daban-daban na Reynolds.An gudanar da gwaje-gwajen a cikin na'urar musayar zafi.Bangon waje na bututu mai karkace ya kasance mai zafi a yanayin zafin jiki akai-akai na 330 K don gwada sigogi don inganta canjin zafi.
A kan fig.1 da tsari yana nuna bututun shigar tef mai murɗaɗi tare da madaidaicin yanayin iyaka da yanki mai raɗaɗi.Kamar yadda aka ambata a baya, saurin gudu da yanayin iyaka ya shafi mashigai da wuraren fita na helix.A yanayin zafin jiki akai-akai, an sanya yanayin da ba zamewa ba akan bangon bututu.Simulation na lamba na yanzu yana amfani da maganin tushen matsa lamba.A lokaci guda, ana amfani da shirin (ANSYS FLUENT 2020R1) don canza ma'auni banbance banbance (PDE) zuwa tsarin ma'auni na algebra ta amfani da hanyar ƙarar iyaka (FMM).Hanyar SIMPLE-oda na biyu (hanyar da ta dace don daidaitattun matsi masu dogaro) tana da alaƙa da matsa lamba.Ya kamata a nanata cewa haɗewar abubuwan da suka rage don taro, kuzari, da daidaiton makamashi bai wuce 103 da 106 ba, bi da bi.
p Tsare-tsare na yanki na zahiri da na lissafi: (a) kusurwar helix 90°, (b) kusurwar helix 45°, (c) babu ruwan sama.
Ana amfani da samfurin iri ɗaya don bayyana kaddarorin nanofluids.Ta hanyar haɗa nanomaterials a cikin ruwa mai tushe (DW), an samar da ruwa mai ci gaba tare da kyawawan kaddarorin thermal.Dangane da wannan, yanayin zafi da saurin ruwan tushe da nanomaterial suna da ƙima ɗaya.Saboda abubuwan da ke sama da kuma zato, ingantaccen kwararar lokaci guda yana aiki a cikin wannan binciken.Yawancin karatu sun nuna tasiri da kuma amfani da fasaha na lokaci-lokaci don nanofluidic flow31,32.
Gudun nanofluids dole ne ya kasance mai ruɗani na Newtonian, wanda ba shi da ma'ana kuma yana tsaye.Ayyukan matsawa da dumama danko ba su da mahimmanci a cikin wannan binciken.Bugu da ƙari, ba a la'akari da kauri na ciki da na waje na bututu.Don haka, ana iya bayyana ma'auni mai yawa, kuzari, da makamashi waɗanda ke ayyana ƙirar thermal kamar haka:
inda \(\overrightarrow {V}\) shine ma'anar saurin haɓaka, Keff = K + Kt shine tasiri mai tasiri na thermal conductivity na covalent da noncovalent nanofluids, kuma ε shine yawan watsawar makamashi.Ingantattun kaddarorin thermophysical na nanofluids, ciki har da yawa (ρ), danko (μ), ƙayyadaddun ƙarfin zafi (Cp) da kuma thermal conductivity (k), wanda aka nuna a cikin tebur, an auna su yayin nazarin gwaji a zazzabi na 308 K1 lokacin amfani da shi. a cikin wadannan simulators.
An yi la'akari da ƙididdiga masu yawa na kwararar nanofluid mai rudani a cikin al'ada da TT tubes a lambobi na Reynolds 7000 ≤ Re ≤ 17000. Wadannan simulations da convective zafi canja wurin coefficients an yi nazari ta hanyar amfani da Mentor's κ-ω turbulence model na shear danniya canja wuri (SST) matsakaita a kan Reyn turbulence. samfurin Navier-Stokes, wanda aka saba amfani dashi a cikin binciken sararin samaniya.Bugu da ƙari, samfurin yana aiki ba tare da aikin bango ba kuma yana daidai kusa da ganuwar 35,36.(SST) κ-ω ma'auni na gudanarwa na tsarin tashin hankali sune kamar haka:
inda \(S \) shine ƙimar ƙimar nau'in, kuma \ (y \) shine nisa zuwa saman da ke kusa.A halin yanzu, \({\alpha}_{1}\), \({\alpha}_{2}\), \({\beta}_{1}\), \({\beta}_{ 2 }\), \({\beta}^{*}\), \({\sigma}_{{k}_{1}}\), \({\sigma}_{{k}_{ 2 }}\), \({\sigma}_{{\omega}_{1}}\) da \({\sigma}_{{\omega}_{2}}\) suna nuni da duk madaidaitan ƙirar ƙira.F1 da F2 ayyuka ne gauraye.Lura: F1 = 1 a cikin iyakar iyaka, 0 a cikin kwarara mai zuwa.
Ana amfani da ma'auni na kimanta aiki don nazarin canjin yanayin zafi mai rikice-rikice, covalent da nanofluid wanda ba ya haɗawa, misali31:
A cikin wannan mahallin, (\(\rho \)), (\ (v \)), (\({D}_{h}\)) da (\(\mu \)) ana amfani da su don yawa, saurin ruwa. , na'ura mai aiki da karfin ruwa diamita da tsauri danko.(\({C}_{p}\, \mathrm{u}\, k\)) - ƙayyadaddun iyawar zafi da yanayin zafi na ruwan da ke gudana.Hakanan, (\(\dot{m}\)) yana nufin kwararar taro, kuma (\({T}_{out}-{T}_{in}\)) yana nufin bambancin zafin shiga da fitarwa.(NFs) yana nufin covalent, nanofluids marasa daidaituwa, kuma (DW) yana nufin ruwa mai narkewa (ruwa mai tushe).\({A}_{s} = \pi DL\), \({\overline{T}}_{f}=\frac{\hagu({T}_{out}-{T}_{in) }\right)}{2}\) da \({\overline{T}}_{w}=\sum \frac{{T}_{w}}{n}\).
Abubuwan thermophysical na ruwa mai tushe (DW), nanofluid mara amfani (GNF-SDBS @ DW), da nanofluid na covalent (GNF-COOH @ DW) an ɗauke su daga littattafan da aka buga (nazarin gwaji), Sn = 308 K, kamar yadda wanda aka nuna a cikin Tebu 134. A cikin gwaji na yau da kullun don samun nanofluid mara amfani (GNP-SDBS @ DW) tare da adadin yawan adadin da aka sani, wasu gram na GNP na farko an auna su akan ma'aunin dijital.Ma'aunin nauyi na SDBS/GNP na asali shine (0.5:1) mai nauyi a cikin DW.A wannan yanayin, covalent (COOH-GNP @ DW) nanofluids an haɗa su ta hanyar ƙara ƙungiyoyin carboxyl zuwa saman GNP ta amfani da matsakaiciyar acidic mai ƙarfi tare da ƙimar girma (1: 3) na HNO3 da H2SO4.An dakatar da nanofluids na covalent da marasa covalent a cikin DW a kashi uku daban-daban masu nauyi kamar 0.025 wt%, 0.05 wt%.da 0.1% na taro.
An gudanar da gwaje-gwajen 'yancin kai na raga a cikin yankuna huɗu daban-daban na lissafin don tabbatar da cewa girman ragar bai shafi simintin ba.Idan aka yi la'akari da bututun torsion na 45 °, adadin raka'a tare da girman naúrar 1.75 mm shine 249,033, adadin raka'a mai girman naúrar 2 mm shine 307,969, adadin naúrar girman 2.25 mm shine 421,406, da adadin raka'a. tare da girman naúrar 2.5 mm 564 940 bi da bi.Bugu da kari, a cikin misalin bututun murdadi mai tsayi 90°, adadin abubuwan da ke da girman simintin 1.75 mm shine 245,531, adadin abubuwan da ke da girman kashi 2 mm 311,584, adadin abubuwan da ke da girman kashi 2.25 mm shine. 422,708, kuma adadin abubuwan da ke da girman kashi 2.5 mm bi da bi shine 573,826.Daidaiton karatun kadarorin thermal kamar (Tout, htc, da Nuavg) yana ƙaruwa yayin da adadin abubuwan ke raguwa.A lokaci guda, daidaiton ƙimar ƙimar ƙima da raguwar matsa lamba ya nuna hali daban-daban (Fig. 2).An yi amfani da Grid (2) azaman babban yankin grid don kimanta halayen thermal-hydraulic a cikin yanayin da aka kwaikwayi.
Gwajin canja wurin zafi da aikin raguwar matsa lamba ba tare da raga ba ta amfani da nau'i-nau'i na bututun DW da aka murɗa a 45° da 90°.
Sakamakon lambobi na yanzu an inganta su don aikin canja wurin zafi da haɗin kai ta hanyar amfani da sanannun ƙwaƙƙwaran alaƙa da daidaito kamar Dittus-Belter, Petukhov, Gnelinsky, Notter-Rouse da Blasius.An gudanar da kwatancen a ƙarƙashin yanayin 7000≤Re≤17000.A cewar fig.3, matsakaita da matsakaicin kurakurai tsakanin sakamakon kwaikwayo da ma'aunin canja wurin zafi shine 4.050 da 5.490% (Dittus-Belter), 9.736 da 11.33% (Petukhov), 4.007 da 7.483% (Gnelinsky), da 3.883% da (4.9%) Nott-Belter).Rose).A wannan yanayin, matsakaita da matsakaicin kurakurai tsakanin sakamakon simintin da ma'aunin ƙima shine 7.346% da 8.039% (Blasius) da 8.117% da 9.002% (Petukhov), bi da bi.
Canja wurin zafi da kaddarorin hydrodynamic na DW a lambobi daban-daban na Reynolds ta amfani da ƙididdiga na ƙididdigewa da alaƙar ƙima.
Wannan sashe yana magana ne akan kaddarorin thermal na waɗanda ba covalent (LNP-SDBS) da covalent (LNP-COOH) nanofluids na ruwa a sassa daban-daban guda uku da lambobi Reynolds a matsayin matsakaici dangane da ruwan tushe (DW).Geometries guda biyu na naɗaɗɗen bel masu zafi (hannun helix 45 ° da 90 °) an tattauna don 7000 ≤ Re ≤ 17000. A cikin fig.4 yana nuna matsakaicin zafin jiki a fitowar nanofluid cikin ruwan tushe (DW) (\(\frac {{{T}_{out}}_{NFs}}{{{T}_{out}}_{ DW }} \)) a (0.025% wt., 0.05% wt. da 0.1% wt.).(\(\frac {{{T}_{out}}_{NFs}}{{{T}_{out}}_{DW}}\)) kodayaushe yana kasa da 1, wanda ke nufin cewa zafin fita ba covalent (VNP-SDBS) da covalent (VNP-COOH) nanofluids ne a kasa da zafin jiki a kanti na tushe ruwa.Mafi ƙasƙanci kuma mafi girma shine 0.1 wt% -COOH@GNPs da 0.1 wt% -SDBS@GNPs, bi da bi.Wannan al'amari ya faru ne saboda karuwa a cikin lambar Reynolds a wani juzu'i na yau da kullun, wanda ke haifar da canji a cikin kaddarorin nanofluid (wato, yawa da danko mai ƙarfi).
Figures 5 da 6 suna nuna matsakaicin halayen canja wurin zafi na nanofluid zuwa ruwa mai tushe (DW) a (0.025 wt.%, 0.05 wt.% da 0.1 wt.%).Matsakaicin kaddarorin canja wurin zafi koyaushe suna da girma fiye da 1, wanda ke nufin cewa ana haɓaka kaddarorin canjin zafi na waɗanda ba covalent (LNP-SDBS) da covalent (LNP-COOH) nanofluids idan aka kwatanta da ruwan tushe.0.1 wt% -COOH@GNPs da 0.1 wt% -SDBS@GNPs sun sami mafi ƙasƙanci kuma mafi girma riba, bi da bi.Lokacin da lambar Reynolds ta ƙaru saboda yawan haɗuwa da ruwa da tashin hankali a cikin bututu 1, aikin canja wurin zafi yana inganta.Ruwan ruwa ta cikin ƙananan giɓi ya kai ga mafi girma, yana haifar da mafi ƙarancin sauri / iyakar zafi, wanda ke ƙara yawan canjin zafi.Ƙara ƙarin nanoparticles zuwa ruwan tushe na iya samun sakamako mai kyau da mara kyau.Abubuwan da ke da fa'ida sun haɗa da ƙara haɗarin nanoparticle, buƙatun haɓaka yanayin zafi mai kyau, da ingantaccen canja wurin zafi.
Matsakaicin canja wurin zafi na nanofluid zuwa ruwa mai tushe dangane da lambar Reynolds don bututun 45° da 90°.
A lokaci guda kuma, mummunan tasiri shine karuwa a cikin danko mai mahimmanci na nanofluid, wanda ya rage motsi na nanofluid, ta haka yana rage matsakaicin lambar Nusselt (Nuavg).Haɓaka haɓakar thermal conductivity na nanofluids (ZNP-SDBS@DW) da (ZNP-COOH@DW) yakamata ya kasance saboda motsin Brownian da microconvection na graphene nanoparticles da aka dakatar a DW37.Ƙarƙashin zafin jiki na nanofluid (ZNP-COOH@DV) ya fi na nanofluid (ZNP-SDBS@DV) da ruwa mai tsabta.Ƙara ƙarin nanomaterials zuwa ruwan tushe yana ƙara ƙarfin zafin su (Table 1)38.
Hoto na 7 yana misalta matsakaicin matsakaicin juzu'i na nanofluids tare da ruwa mai tushe (DW) (f(NFs)/f(DW)) a cikin kashi mai yawa (0.025%, 0.05% da 0.1%).Matsakaicin matsakaicin juzu'i koyaushe shine ≈1, wanda ke nufin cewa waɗanda ba covalent (GNF-SDBS@DW) da covalent (GNF-COOH@DW) nanofluids suna da juzu'i iri ɗaya da ruwan tushe.Mai musayar zafi tare da ƙasan sarari yana haifar da ƙarin toshewar kwarara kuma yana ƙara juzu'in kwarara1.Ainihin, ƙimar juzu'i yana ƙaruwa kaɗan tare da ƙara yawan juzu'in nanofluid.Babban hasara na juzu'i yana faruwa ne ta hanyar haɓakar danko mai ƙarfi na nanofluid da ƙara yawan damuwa a saman tare da babban adadin nanographene a cikin ruwan gindi.Teburin (1) ya nuna cewa danko mai ƙarfi na nanofluid (ZNP-SDBS @ DV) ya fi na nanofluid (ZNP-COOH @ DV) a daidai wannan nauyin nauyin, wanda ke hade da ƙari na abubuwan da ke faruwa.wakilai masu aiki akan nanofluid mara amfani.
A kan fig.8 yana nuna nanofluid idan aka kwatanta da tushen ruwa (DW) (\(\frac{{\Delta P}_{NFs}}{{\Delta P}_{DW}})) a (0.025%, 0.05% da 0.1% ).Nanofluid mara amfani (GNPs-SDBS@DW) nanofluid ya nuna matsakaicin matsakaicin asarar matsa lamba, kuma tare da haɓaka yawan adadin zuwa 2.04% don 0.025% wt., 2.46% don 0.05% wt.kuma 3.44% don 0.1% wt.tare da ƙara girma (kwanuwar helix 45° da 90°).A halin yanzu, nanofluid (GNPs-COOH@DW) ya nuna ƙarancin matsakaicin asarar matsa lamba, yana ƙaruwa daga 1.31% a 0.025% wt.ya canza zuwa +1.65% da -0.05%.Matsakaicin asarar matsa lamba na 0.05 wt.% -COOH@NP da 0.1 wt.% -COOH@NP shine 1.65%.Kamar yadda ake iya gani, raguwar matsa lamba yana ƙaruwa tare da ƙara lambar Re a kowane yanayi.Ƙarar raguwar matsa lamba a manyan ƙimar Re ana nuna ta ta dogaro kai tsaye ga kwararar ƙara.Sabili da haka, lambar Re mafi girma a cikin bututu tana kaiwa zuwa raguwar matsa lamba, wanda ke buƙatar haɓaka ƙarfin famfo39,40.Bugu da ƙari, asarar matsa lamba ya fi girma saboda mafi girma na eddies da tashin hankali da aka haifar da babban yanki na sararin samaniya, wanda ya kara yawan hulɗar matsa lamba da ƙarfin inertia a cikin iyaka Layer1.
Gabaɗaya, ƙa'idodin kimanta aikin (PEC) don waɗanda ba su da haɗin gwiwa (VNP-SDBS@DW) da covalent (VNP-COOH@DW) nanofluids ana nuna su a cikin Fig.9. Nanofluid (ZNP-SDBS @ DV) ya nuna ƙimar PEC mafi girma fiye da (ZNP-COOH @ DV) a cikin lokuta biyu (ƙungiya na 45 ° da 90 °) kuma an inganta shi ta hanyar ƙara yawan juzu'i, misali, 0.025. wt.%.shine 1.17, 0.05 wt.% shine 1.19 kuma 0.1 wt.% shine 1.26.A halin yanzu, ƙimar PEC ta amfani da nanofluids (GNPs-COOH@DW) sun kasance 1.02 don 0.025 wt%, 1.05 don 0.05 wt%, 1.05 don 0.1 wt%.a cikin kowane hali (kwanuwar helix 45 ° da 90 °).1.02.A matsayinka na mai mulki, tare da karuwa a cikin lambar Reynolds, tasirin thermal-hydraulic yana raguwa sosai.Yayin da lambar Reynolds ke ƙaruwa, raguwa a cikin ƙimar ingancin thermal-hydraulic yana da alaƙa da tsari tare da haɓaka (NuNFs/NuDW) da raguwa a (fNFs/fDW).
Abubuwan hydrothermal na nanofluids dangane da ruwa mai tushe dangane da lambobin Reynolds don bututu masu kusurwa 45° da 90°.
Wannan sashe yana tattauna abubuwan thermal Properties na ruwa (DW), wadanda ba covalent (VNP-SDBS@DW), da covalent (VNP-COOH@DW) nanofluids a daban-daban taro taro uku da kuma Reynolds lambobin.An yi la'akari da nau'ikan geometries masu murɗa zafin bel guda biyu a cikin kewayon 7000 ≤ Re ≤ 17000 dangane da bututu na al'ada (kusurwoyin helix 45° da 90°) don kimanta matsakaicin aikin thermal-hydraulic.A kan fig.10 yana nuna zafin ruwa da nanofluids a wurin fita azaman matsakaita ta amfani da (helix kusurwa 45° da 90°) don bututu gama gari (\(\frac {{{T}_{out}}_{Twisted}}{{ {T} _{fita}_{Regular}}\)).Non-covalent (GNP-SDBS@DW) da covalent (GNP-COOH@DW) nanofluids suna da nau'i nau'i nau'i nau'i nau'i uku kamar 0.025 wt%, 0.05 wt% da 0.1 wt%.Kamar yadda aka nuna a cikin fig.11, matsakaita darajar zafin da ake fitarwa (\(\frac {{{T}_{out}}_{Twisted}}{{{T}_{out}}_{Plain}}\))> 1, yana nuna cewa (45° da 90° helix angle) zafin jiki a mashigar na'urar musayar zafi ya fi na bututu na al'ada muhimmanci, saboda tsananin tashin hankali da mafi kyawun haɗawar ruwa.Bugu da kari, zafin jiki a mashigar DW, wadanda ba na covalent da nanofluids na covalent sun ragu tare da karuwar lambar Reynolds.Ruwan tushe (DW) yana da matsakaicin matsakaicin zafin fitarwa.A halin yanzu, mafi ƙarancin ƙima yana nufin 0.1 wt% -SDBS@GNPs.Non-covalent (GNPs-SDBS@DW) nanofluids sun nuna matsakaicin matsakaicin matsakaicin zafi idan aka kwatanta da nanofluids na covalent (GNPs-COOH@DW).Tun da murɗaɗɗen tef ɗin yana sa filin kwarara ya zama mai gauraye, zafi na kusa da bango zai iya wucewa cikin ruwa cikin sauƙi, yana ƙara yawan zafin jiki.Ƙarƙashin juzu'i-zuwa-tef ɗin yana haifar da mafi kyawun shiga kuma don haka mafi kyawun canja wurin zafi.A gefe guda, ana iya ganin cewa tef ɗin da aka yi birgima yana kula da ƙananan zafin jiki a bango, wanda hakan yana ƙara Nuavg.Don murɗaɗɗen abubuwan shigar da tef, ƙimar Nuavg mafi girma tana nuna ingantaccen canja wurin zafi a cikin tube22.Saboda ƙaƙƙarfan hanyar kwarara da ƙarin haɗuwa da tashin hankali, lokacin zama yana ƙaruwa, yana haifar da haɓakar zafin ruwa a cikin fitarwa41.
Lambobin Reynolds na nau'ikan nanofluids daban-daban dangane da yanayin fitarwa na bututu na al'ada (45° da 90° kusurwoyin helix).
Matsakaicin canja wurin zafi (45° da 90° helix kusurwa) tare da lambobi na Reynolds don nau'ikan nanofluids idan aka kwatanta da bututu na al'ada.
Babban hanyar inganta naɗaɗɗen kaset zafi canja wurin shi ne kamar haka: 1. Rage na'ura mai aiki da karfin ruwa diamita na zafi musayar bututu yana haifar da karuwa a cikin gudu gudu da curvature, wanda bi da bi yana kara karfi danniya a bango da kuma inganta na biyu motsi.2. Saboda toshewar tef ɗin iska, saurin gudu a bangon bututu yana ƙaruwa, kuma kauri na iyakar iyaka yana raguwa.3. Ƙaƙwalwar karkace a bayan bel ɗin da aka karkace yana haifar da karuwa a cikin sauri.4. Ƙwayoyin da aka haifar suna inganta haɗuwar ruwa tsakanin tsakiya da yankunan kusa da bango na kwarara42.A kan fig.11 da fig.12 yana nuna kaddarorin canja wurin zafi na DW da nanofluids, alal misali (matsakaicin canjin zafi da matsakaicin lambar Nusselt) azaman matsakaici ta amfani da bututun saka tef ɗin murɗaɗi idan aka kwatanta da bututu na al'ada.Non-covalent (GNP-SDBS@DW) da covalent (GNP-COOH@DW) nanofluids suna da nau'i nau'i nau'i nau'i nau'i uku kamar 0.025 wt%, 0.05 wt% da 0.1 wt%.A cikin duka masu musayar zafi (45 ° da 90 ° helix kwana) matsakaicin aikin canja wurin zafi shine> 1, yana nuna haɓakar ƙimar canjin zafi da matsakaicin lambar Nusselt tare da bututun da aka naɗe idan aka kwatanta da bututu na al'ada.Non-covalent (GNPs-SDBS@DW) nanofluids sun nuna matsakaicin matsakaicin haɓaka canjin zafi fiye da covalent (GNPs-COOH@DW) nanofluids.A Re = 900, 0.1 wt% ingantawa a cikin aikin canja wurin zafi -SDBS@GNPs don masu musayar zafi guda biyu (45 ° da 90 ° helix kwana) ya kasance mafi girma tare da darajar 1.90.Wannan yana nufin cewa tasirin TP na uniform ya fi mahimmanci a ƙananan saurin ruwa (lambar Reynolds) 43 da ƙara ƙarfin tashin hankali.Saboda gabatarwar vortices da yawa, ƙimar canja wurin zafi da matsakaicin adadin nusselt na bututun TT sun fi girma fiye da bututu na al'ada, yana haifar da ƙaramin iyaka.Shin kasancewar HP yana ƙara ƙarfin tashin hankali, haɗakar ruwa mai aiki da haɓakar canjin zafi idan aka kwatanta da bututun tushe (ba tare da saka tef ɗin murɗaɗi ba)21.
Matsakaicin lambar Nusselt (hannun helix 45° da 90°) tare da lambar Reynolds don nau'ikan nanofluids idan aka kwatanta da bututun al'ada.
Figures 13 da 14 suna nuna matsakaicin matsakaicin juzu'i (\(\frac{{f}_{Twisted}}{{f}_{Plain}}\)) da asarar matsa lamba (\(\frac{{\Delta P}) _ {Twisted}}{{\Delta P}_{Plain}}\}} kimanin 45° da 90° don bututu na al'ada ta amfani da DW nanofluids, (GNPs-SDBS@DW) da (GNPs-COOH@DW) ion musayar ya ƙunshi ( 0.025 wt %, 0.05 wt % da 0.1 wt %). {{f}_{Plain} }\)) da asarar matsa lamba (\(\frac{{ \Delta P}_{Twisted}}{{\Delta P }_{Plain}}\}) raguwa. lokuta, ƙimar juzu'i da asarar matsa lamba sun fi girma a ƙananan lambobin Reynolds Matsakaicin ƙimar juzu'i da asarar matsa lamba suna tsakanin 3.78 da 3.12 Matsakaicin ƙimar juzu'i da asarar matsa lamba sun nuna cewa (45° helix Angle da 90°) farashin musayar zafi sau uku fiye da bututu na al'ada. Bugu da ƙari, lokacin da ruwa mai aiki ke gudana a cikin sauri mafi girma, ƙimar juzu'i na raguwa. yana raguwa, wanda ke haifar da raguwar tasirin danko mai ƙarfi akan yankin da abin ya shafa, raguwar saurin gradients da damuwa mai ƙarfi kuma, saboda haka, raguwar ƙima na friction21.Ingantattun tasirin toshewa saboda kasancewar TT da haɓakar juyawa yana haifar da asarar matsa lamba mai yawa don bututun TT daban-daban fiye da bututun tushe.Bugu da ƙari, don duka bututun tushe da bututun TT, ana iya ganin cewa raguwar matsa lamba yana ƙaruwa tare da saurin ruwa mai aiki43.
Coefficient of friction (45° da 90° helix kusurwa) da lambar Reynolds don nau'ikan nanofluids idan aka kwatanta da bututu na al'ada.
Rashin matsi (45° da 90° helix kusurwa) azaman aikin lambar Reynolds don nau'ikan nanofluids dangane da bututu na al'ada.
A taƙaice, Hoto na 15 yana nuna ƙa'idodin kimanta aikin (PEC) don masu musayar zafi tare da kusurwa 45° da 90° idan aka kwatanta da bututun fili (\(\frac {{PEC}_{Twisted}}{{PEC}_{Plain}} \ )) a cikin (0.025 wt.%, 0.05 wt.% da 0.1 wt.%) ta amfani da DV, (VNP-SDBS@DV) da covalent (VNP-COOH@DV) nanofluids.Ƙimar (\(\frac{{PEC}_{Twisted}}{{PEC}_{Plain}}\))> 1 a cikin nau'i biyu (45° da 90° helix kwana) a cikin mai musayar zafi.Bugu da kari, (\frac {{PEC}_{Twisted}}{{PEC}_{Plain}}\)) ya kai mafi kyawun darajarsa a Re = 11,000.Mai musanya zafi na 90° yana nuna ɗan ƙaruwa a cikin (\ (\frac{{PEC}_{Twisted}}{{PEC}_{Plain}}\)) idan aka kwatanta da mai 45° mai musayar zafi., A Re = 11,000 0.1 wt% -GNPs@SDBS yana wakiltar mafi girma (\(\frac {{PEC}_{Twisted}}{{PEC}_{Plain}})) ƙimomi, misali 1.25 don 45° kusurwar musayar zafi da kuma 1.27 don 90 ° kusurwa mai musayar zafi.Ya fi ɗaya girma a kowane kashi na yawan juzu'i, wanda ke nuna cewa bututu masu murɗaɗɗen kaset sun fi bututu na al'ada.Musamman ma, ingantacciyar canjin zafi da aka samar ta hanyar abubuwan da aka sanyawa tef ya haifar da haɓakar hasarar gogayya22.
Ma'aunin inganci don lambar Reynolds na nanofluids daban-daban dangane da bututu na al'ada (45° da 90° kusurwar helix).
Shafi A yana nuna sauye-sauye na 45° da 90° masu musayar zafi a Re = 7000 ta amfani da DW, 0.1 wt% -GNP-SDBS@DW da 0.1 wt% -GNP-COOH@DW.Matsakaicin madaidaicin jirgin sama shine mafi kyawun fasalin tasirin abin da ake saka kintinkiri mai murɗa akan babban kwarara.Yin amfani da 45° da 90° masu musayar zafi yana nuna cewa saurin da ke kusa da bango ya kusan iri ɗaya.A halin yanzu, Shafi B yana nuna madaidaicin madaukai na 45° da 90° masu musayar zafi a Re = 7000 ta amfani da DW, 0.1 wt% -GNP-SDBS@DW da 0.1 wt% -GNP-COOH@DW.Madaidaicin madaukai suna cikin wurare daban-daban guda uku (yanki), misali, Plain-1 (P1 = -30mm), Plain-4 (P4 = 60mm) da Plain-7 (P7 = 150mm).Gudun gudu kusa da bangon bututu shine mafi ƙanƙanta kuma saurin ruwa yana ƙaruwa zuwa tsakiyar bututun.Bugu da ƙari, lokacin wucewa ta hanyar iska, yanki na ƙananan hanzari kusa da bango yana ƙaruwa.Wannan shi ne saboda haɓakar iyakokin iyaka na hydrodynamic, wanda ke ƙara yawan kauri na yanki mai ƙananan sauri kusa da bango.Bugu da ƙari, haɓaka lambar Reynolds yana ƙara yawan matakin saurin gudu a duk sassan giciye, ta haka yana rage kauri na ƙananan saurin yanki a cikin tashar39.
An kimanta nanosheets na graphene da ba a haɗa su ba a cikin murɗaɗɗen tef ɗin tare da kusurwar helix na 45° da 90°.Ana warware ma'aunin zafi da ƙima ta hanyar amfani da SST k-omega turbulence model a 7000 ≤ Re ≤ 17000. Ana ƙididdige kaddarorin thermophysical a Tin = 308 K. A lokaci guda zafi bangon tube mai murdawa a zazzabi na 330 K. COOH @ DV) An diluted a cikin adadi mai yawa uku, misali (0.025 wt.%, 0.05 wt.% da 0.1 wt.%).Binciken na yanzu ya yi la'akari da manyan abubuwa guda shida: zafin fitarwa, ƙimar canja wurin zafi, matsakaicin lambar Nusselt, ƙididdiga na juzu'i, asarar matsa lamba, da ma'auni na kimanta aiki.Ga babban binciken:
Matsakaicin zazzabi mai fita ({{T}_{out}}_{Nanofluids}\)/\({T}_{out}}_{Basefluid})) koyaushe yana ƙasa da 1, wanda ke nufin cewa rashin yaduwa Zazzaɓin fitarwa na valence (ZNP-SDBS@DV) da covalent (ZNP-COOH@DV) nanofluids ya yi ƙasa da na tushen ruwa.A halin yanzu, matsakaicin matsakaicin yanayin fitarwa (\({{T}_{out}}_{Twisted}\)/\({{T}_{out}}_{Plain}\))> 1, yana nuni ga Gaskiyar cewa (45 ° da 90 ° helix kwana) yanayin fitarwa ya fi girma fiye da tubes na al'ada.
A cikin duka biyun, matsakaicin ƙimar kaddarorin canja wurin zafi (nanofluid / ruwa mai tushe) da (ƙwanƙwasa bututu / bututu na al'ada) koyaushe suna nunawa> 1.Non-covalent (GNPs-SDBS@DW) nanofluids sun nuna matsakaicin karuwa a cikin canjin zafi, daidai da covalent (GNPs-COOH @ DW) nanofluids.
Matsakaicin matsakaicin juzu'i (\({f}_{Nanofluids}/{f}_{Basefluid}\)) na waɗanda ba covalent (VNP-SDBS@DW) da covalent (VNP-COOH@DW) nanofluids koyaushe ne ≈1 .gogayya na waɗanda ba covalent (ZNP-SDBS@DV) da covalent (ZNP-COOH@DV) nanofluids (\({f}_{Twisted}/{f}_{Plain}\)) kullum> 3.
A cikin duka biyun (45° da 90° helix kwana), nanofluids (GNPs-SDBS@DW) ya nuna mafi girma (\({\Delta P}_{Nanofluids}/{\Delta P}_{Basefluid}\)) 0.025 wt .% don 2.04%, 0.05 wt.% don 2.46% da 0.1 wt.% don 3.44%.A halin yanzu, (GNPs-COOH@DW) nanofluids sun nuna ƙananan (({\Delta P}_{Nanofluids}/{\Delta P}_{Basefluid}\)) daga 1.31% na 0.025 wt.% zuwa 1.65% shine 0.05 % ta nauyi.Bugu da kari, matsakaita asarar matsa lamba (\({\Delta P}_{Twisted}/{\Delta P}_{Plain}\) na marasa haɗin gwiwa (GNPs-SDBS@DW) da covalent (GNPs-COOH@DW) ))) nanofluids kullum>3.
A cikin lokuta biyu (45° da 90° helix kusurwa), nanofluids (GNPs-SDBS@DW) ya nuna mafi girma ({PEC}_{Nanofluids}/{PEC} _{Basefluid}\)) @DW darajar) , misali 0.025 wt.% - 1.17, 0.05 wt.% - 1.19, 0.1 wt.% - 1.26.A wannan yanayin, ƙimar ({PEC}_{Nanofluids}/{PEC}_{Basefluid}\)) ta amfani da (GNPs-COOH@DW) nanofluids sune 1.02 don 0.025 wt.%, 1.05 don 0 , 05 wt.% kuma 1.02 shine 0.1% ta nauyi.Bugu da kari, a Re = 11,000, 0.1 wt% -GNPs@SDBS ya nuna mafi girman dabi'u (\({PEC}_{Twisted}/{PEC}_{Plain}\)), kamar 1.25 don 45° kusurwar helix da 90° helix kwana 1.27.
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