Xaiv ntawm cov khoom siv hluav taws xob tam sim no siv tsis pub dhau tsib feeb. Txhua lub koom haum uas tsim thiab muag cov khoom siv, raws li txoj cai, muab txhua tus nrog lawv cov kev xaiv xaiv. Nws tuaj yeem rub tawm dawb los ntawm lub tuam txhab lub vev xaib, lossis lawv cov kws tshaj lij yuav tuaj rau koj lub hoobkas thiab nruab nws dawb. Txawm li cas los xij, qhov tseeb npaum li cas yog qhov tshwm sim ntawm cov kev suav no, nws puas tuaj yeem ntseeg tau thiab yog cov chaw tsim khoom tsis txawj ntse thaum sib ntaus sib tua nrog nws cov neeg sib tw? Kev kuaj xyuas lub laij lej hluav taws xob yuav tsum muaj kev paub lossis tsawg kawg yog kev nkag siab txog cov txheej txheem rau kev suav cov khoom siv hluav taws xob niaj hnub. Wb sim to taub cov ntsiab lus.
Dab tsi yog qhov hloov pauv kub
Ua ntej ua qhov kev suav ntawm cov khoom siv hluav taws xob, cia peb nco ntsoov cov cuab yeej no yog dab tsi? Lub tshav kub thiab huab cua hloov khoom siv (aka lub tshav kub exchanger, aka lub tshav kub exchanger, los yog TOA) yogib qho khoom siv rau kev xa cov cua sov los ntawm ib lub coolant mus rau lwm tus. Nyob rau hauv tus txheej txheem ntawm kev hloov qhov kub thiab txias ntawm cov khoom siv hluav taws xob, lawv qhov ntom ntom thiab, raws li, cov ntsuas loj ntawm cov khoom kuj hloov. Yog vim li cas cov txheej txheem no hu ua cua sov thiab huab hwm coj hloov.
Yam hloov pauv cua sov
Tam sim no cia peb tham txog hom kev hloov pauv cua sov - tsuas muaj peb ntawm lawv. Radiative - tshav kub hloov vim hluav taws xob. Ua piv txwv, xav txog kev sunbathing ntawm lub puam ntawm hnub sov sov. Thiab cov khoom siv hluav taws xob zoo li no tuaj yeem pom muaj nyob hauv khw (tube cua sov). Txawm li cas los xij, feem ntau rau cov cua sov hauv thaj chaw, chav nyob hauv ib chav tsev, peb yuav cov roj lossis hluav taws xob hluav taws xob. Qhov no yog ib qho piv txwv ntawm lwm hom kev hloov hluav taws xob - convection. Convection tuaj yeem yog ntuj, yuam (hood, thiab muaj qhov sib pauv cua sov hauv lub thawv) lossis mechanically tsav (nrog rau kiv cua, piv txwv li). Hom tom kawg no siv tau ntau dua.
Txawm li cas los xij, txoj hauv kev zoo tshaj plaws los hloov cov cua sov yog conduction, lossis, raws li nws tseem hu ua, conduction (los ntawm lus Askiv. conduction - "conduction"). Txhua tus kws tshaj lij uas yuav ua qhov ntsuas cua sov ntawm lub tshuab hluav taws xob, ua ntej ntawm tag nrho, xav txog yuav ua li cas xaiv cov cuab yeej siv tau zoo hauv qhov tsawg kawg nkaus. Thiab nws yog ua tau kom ua tiav qhov no precisely vim thermal conductivity. Ib qho piv txwv ntawm qhov no yog qhov ua tau zoo tshaj plaws TOA niaj hnub no - phaj kub exchangers. Lub phaj kub exchanger, raws li lub ntsiab txhais, yog lub tshav kub exchanger uas hloov tshav kub los ntawm ib tug coolant mus rau lwm tus los ntawm ib tug phab ntsa sib cais lawv. Qhov siab tshaj plawsthaj chaw muaj peev xwm sib cuag ntawm ob lub xov xwm, ua ke nrog cov ntaub ntawv xaiv kom raug, phaj profile thiab thickness, tso cai rau txo qhov loj ntawm cov khoom xaiv thaum tswj hwm tus yam ntxwv tseem ceeb hauv cov txheej txheem thev naus laus zis.
Type of heat exchangers
Ua ntej xam cov khoom siv hluav taws xob, nws txiav txim siab nrog nws hom. Tag nrho TOA tuaj yeem muab faib ua ob pawg loj: recuperative thiab regenerative heat exchangers. Lub ntsiab sib txawv ntawm lawv yog raws li nram no: nyob rau hauv regenerative TOAs, tshav kub pauv tshwm sim los ntawm ib tug phab ntsa cais ob coolants, thaum nyob rau hauv regenerative sawv daws yuav, ob tug xov xwm muaj kev sib cuag ncaj qha rau ib leeg, feem ntau sib tov thiab yuav tsum tau tom qab sib cais nyob rau hauv tshwj xeeb separators. Regenerative heat exchangers muab faib rau hauv kev sib xyaw thiab cov khoom siv hluav taws xob sib txuas nrog cov ntim khoom (nyob ruaj ruaj, poob lossis nruab nrab). Hais lus ntxhib, ib lub thoob dej kub, raug Frost, los yog ib khob ntawm cov tshuaj yej kub, teem kom txias nyob rau hauv lub tub yees (tsis txhob ua li no!) - qhov no yog ib tug piv txwv ntawm xws li ib tug sib tov TOA. Thiab ncuav cov tshuaj yej rau hauv saucer thiab txias nws nyob rau hauv txoj kev no, peb tau txais ib qho piv txwv ntawm ib tug regenerative tshav kub exchanger nrog ib tug nozzle (lub saucer nyob rau hauv cov piv txwv no plays lub luag hauj lwm ntawm lub nozzle), uas thawj zaug hu rau cov huab cua puag ncig thiab yuav siv sij hawm nws kub, thiab tom qab ntawd tshem tawm ib feem ntawm cov cua sov los ntawm cov tshuaj yej kub poured rau hauv nws, nrhiav kom coj ob qho tib si tawm rau hauv thermal equilibrium. Txawm li cas los xij, raws li peb tau pom ua ntej lawm, nws yog qhov ua tau zoo dua los siv thermal conductivity kom hloov cov cua sov ntawm ib nrab mus rau lwm qhov, yog li ntawd. Kev hloov hluav taws xob ntau dua muaj txiaj ntsig (thiab siv dav) TOA niaj hnub no, tau kawg, cov khoom siv rov ua dua tshiab.
Thermal and structural design
Txhua qhov kev suav ntawm cov khoom siv hluav taws xob rov qab tuaj yeem ua tiav raws li cov txiaj ntsig ntawm thermal, hydraulic thiab lub zog suav. Lawv yog cov tseem ceeb, yuav tsum tau tsim cov cuab yeej tshiab thiab tsim lub hauv paus ntawm cov txheej txheem rau kev suav cov qauv tom ntej ntawm ib kab ntawm cov cuab yeej zoo sib xws. Lub luag haujlwm tseem ceeb ntawm kev suav thermal ntawm TOA yog los txiav txim siab qhov xav tau ntawm thaj chaw ntawm qhov chaw sib pauv cua sov rau kev ua haujlwm ruaj khov ntawm cov khoom siv hluav taws xob thiab kev tswj xyuas qhov yuav tsum tau ua ntawm cov xov xwm ntawm qhov hluav taws xob. Heev feem ntau, nyob rau hauv xws li kev xam, engineers tau muab arbitrary qhov tseem ceeb ntawm qhov ceeb thawj thiab loj yam ntxwv ntawm lub neej yav tom ntej cov khoom (khoom, yeeb nkab txoj kab uas hla, phaj qhov ntev, nras geometry, hom thiab cov khoom ntawm fins, thiab lwm yam), yog li ntawd, tom qab lub thermal laij lej, lawv feem ntau ua tiav kev xam pom ntawm lub tshav kub exchanger. Tom qab tag nrho, yog hais tias nyob rau hauv thawj theem tus engineer xam qhov yuav tsum tau deg cheeb tsam rau ib tug muab txoj kab uas hla, piv txwv li, 60 mm, thiab lub tshav kub exchanger ntev tau tig tawm mus txog rau caum meters, ces nws yuav muaj ntau lub laj thawj los xav txog kev hloov. mus rau lub tshav kub exchanger multi-pass, los yog mus rau lub plhaub-thiab-tube hom, los yog ua kom lub cheeb ntawm cov hlab.
Hydraulic xam
Hydraulic lossis hydromechanical, nrog rau kev suav aerodynamic tau ua tiav txhawm rau txiav txim siab thiab ua kom zoo dua hydraulic(aerodynamic) siab poob nyob rau hauv lub tshav kub exchanger, raws li zoo raws li xam cov nqi zog los kov yeej lawv. Kev suav ntawm txhua txoj hauv kev, cov channel lossis cov yeeb nkab rau kev nkag mus ntawm lub tshuab ua kom txias ua rau lub luag haujlwm tseem ceeb rau ib tus neeg - txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm Ntawd yog, ib qho nruab nrab yuav tsum hloov mus, thiab lwm qhov tau txais cua sov ntau li ntau tau hauv lub sijhawm tsawg kawg nkaus ntawm nws cov dej ntws. Rau qhov no, feem ntau siv cov khoom siv hluav taws xob sib txuas ntxiv, nyob rau hauv daim ntawv ntawm kev txhim kho nto ribbing (kom cais cov ciam teb laminar sublayer thiab txhim khu kev khiav turbulence). Qhov zoo tshaj qhov sib npaug ntawm hydraulic poob, tshav kub pauv thaj chaw, qhov hnyav thiab qhov loj me thiab tshem tawm thermal zog yog qhov tshwm sim ntawm kev sib xyaw ua ke ntawm thermal, hydraulic thiab cov qauv ntawm TOA.
Kaw suav teb
Kev txheeb xyuas qhov ntsuas ntawm cov khoom siv hluav taws xob yog ua tiav hauv rooj plaub thaum nws yuav tsum tau nteg cov npoo ntawm lub hwj chim lossis raws li thaj tsam ntawm qhov chaw sib pauv cua sov. Qhov saum npoo yog tshwj tseg rau ntau yam laj thawj thiab ntau qhov xwm txheej: yog tias nws xav tau los ntawm cov ntsiab lus ntawm kev siv, yog tias cov chaw tsim khoom txiav txim siab ua ib qho ntxiv kom paub tseeb tias xws li cov khoom siv hluav taws xob yuav ncav cuag cov tswj hwm thiab txo qhov ua yuam kev. cov kev suav. Qee qhov xwm txheej, kev rov ua dua yuav tsum tau ua kom dhau los ntawm cov txiaj ntsig ntawm kev tsim qhov ntev, thaum lwm tus (evaporators, economizers), cov npoo npoo tshwj xeeb tau qhia tshwj xeeb hauv kev suav cov hluav taws xob hloov hluav taws xob, rau kev sib kis los ntawm cov roj compressor tam sim no nyob rau hauv lub tub yees Circuit Court.. Thiab dej tsis zooyuav tsum coj mus rau hauv tus account. Tom qab qee lub sij hawm ntawm kev ua haujlwm tsis cuam tshuam ntawm cov khoom siv hluav taws xob, tshwj xeeb tshaj yog nyob rau hauv qhov kub thiab txias, qhov ntsuas tau nyob ntawm qhov chaw sib hloov ntawm cov khoom siv hluav taws xob, txo cov cua sov hloov coefficient thiab inevitably ua rau parasitic txo qis hauv kev tshem tawm cua sov. Yog li ntawd, ib tug kws txawj engineers, thaum xam cov dej-rau-dej kub exchanger, them tshwj xeeb mloog mus ntxiv redundancy ntawm tshav kub exchanger nto. Kev txheeb xyuas kev suav kuj tseem ua tiav txhawm rau pom tias cov khoom siv xaiv yuav ua haujlwm li cas hauv lwm hom, theem nrab. Piv txwv li, nyob rau hauv nruab nrab cua txias (chaw units), thawj thiab thib ob cua sov cua sov, uas yog siv nyob rau hauv lub caij txias, feem ntau yog siv nyob rau hauv lub caij ntuj sov kom txias cov cua tuaj, muab dej txias rau cov cua kub exchanger raj. Yuav ua li cas lawv yuav ua haujlwm thiab qhov ntsuas yuav muab tawm li cas, tso cai rau koj los ntsuas qhov kev txheeb xyuas qhov tseeb.
Tshawb nrhiav suav
Kev tshawb fawb suav ntawm TOA yog ua los ntawm cov txiaj ntsig tau los ntawm kev ntsuas cua sov thiab kev txheeb xyuas. Lawv yog ib qho tsim nyog, raws li txoj cai, ua qhov kev hloov kho zaum kawg rau kev tsim cov cuab yeej tsim. Lawv kuj tau ua tiav txhawm rau txhawm rau kho qhov sib npaug uas tau muab tso rau hauv cov qauv kev suav ntawm TOA, tau txais kev pom zoo (raws li cov ntaub ntawv sim). Ua kev tshawb fawb suav nrog kaum thiab qee zaum pua pua ntawm kev suav raws li ib txoj kev npaj tshwj xeeb tsim thiab siv hauv kev tsim khoom raws lilej txoj kev xav ntawm kev npaj kev sim. Raws li qhov tshwm sim, qhov cuam tshuam ntawm ntau yam mob thiab lub cev muaj nuj nqis ntawm TOA cov ntsuas kev ua tau zoo tau tshwm sim.
Lwm suav suav
Thaum xam qhov chaw sib pauv cua sov, tsis txhob hnov qab txog qhov tsis kam ntawm cov ntaub ntawv. TOA lub zog suav nrog suav nrog kev kuaj xyuas lub tsev tsim rau kev ntxhov siab, rau kev sib tw, rau kev siv lub sijhawm ua haujlwm siab tshaj plaws rau cov khoom thiab cov rooj sib txoos ntawm cov khoom siv hluav taws xob yav tom ntej. Nrog qhov tsawg kawg nkaus qhov ntev, cov khoom yuav tsum muaj zog, ruaj khov thiab lav kev ruaj ntseg hauv ntau yam, txawm tias qhov kev xav tau tshaj plaws ntawm kev ua haujlwm.
Kev suav lej yog ua tiav txhawm rau txhawm rau txiav txim siab ntau yam ntawm cov khoom siv hluav taws xob sib txawv hauv kev ua haujlwm sib txawv.
Kub exchanger tsim hom
Recuperative TOA los ntawm kev tsim qauv tuaj yeem muab faib ua ntau pawg. Cov nto moo tshaj plaws thiab dav siv yog phaj kub exchangers, cua (tubular finned), plhaub-thiab-tube, raj-hauv-pipe tshav kub exchangers, plhaub-thiab-phaj thiab lwm yam. Kuj tseem muaj ntau hom kab txawv thiab tshwj xeeb tshaj plaws, xws li kauv (coil heat exchanger) lossis hom scraped, uas ua haujlwm nrog cov kua nplaum los yog tsis-Newtonian, nrog rau ntau hom.
Pipe-hauv-pipe heat exchangers
Cia peb xav txog qhov yooj yim tshaj plaws ntawm kev suav "cov yeeb nkab hauv cov yeeb nkab" kub exchanger. Raws li txoj cai, hom TOA no yog qhov yooj yim tshaj plaws. Raws li txoj cai, lawv cia mus rau hauv lub puab raj ntawm lub apparatuskub coolant, kom txo tau poob, thiab ib tug txias coolant yog launched rau hauv lub casing, los yog mus rau hauv lub txheej yeeb nkab. Tus engineer txoj hauj lwm nyob rau hauv cov ntaub ntawv no yog txo los txiav txim qhov ntev ntawm xws li ib tug kub exchanger raws li xam qhov chaw ntawm lub tshav kub exchanger nto thiab cov diameters muab.
Ntawm no nws tsim nyog ntxiv tias hauv thermodynamics lub tswv yim ntawm cov khoom siv hluav taws xob zoo tshaj plaws tau qhia, uas yog, lub cuab yeej ntawm qhov ntev tsis kawg, qhov twg cov khoom siv hluav taws xob ua haujlwm hauv qhov sib txawv, thiab qhov kub sib txawv yog ua tiav ntawm lawv.. Cov yeeb nkab-hauv-pipe tsim yog ze tshaj plaws kom ua tau raws li cov cai no. Thiab yog tias koj khiav cov coolants hauv countercurrent, ces nws yuav yog qhov hu ua "tiag counterflow" (thiab tsis hla, xws li hauv phaj TOAs). Lub taub hau kub yog ua haujlwm zoo tshaj plaws nrog xws li lub koom haum ntawm kev txav. Txawm li cas los xij, thaum xam "cov yeeb nkab hauv cov yeeb nkab" cov khoom siv hluav taws xob, ib qho yuav tsum muaj tseeb thiab tsis txhob hnov qab txog cov khoom siv logistics, nrog rau kev yooj yim ntawm kev teeb tsa. Qhov ntev ntawm lub eurotruck yog 13.5 meters, thiab tsis yog tag nrho cov technical thaj chaw tau yoog rau skidding thiab installation ntawm cov khoom ntawm qhov ntev.
Shell and tube heat exchangers
Yog li ntawd, feem ntau qhov kev suav ntawm cov cuab yeej zoo li no ntws mus rau hauv kev suav ntawm lub plhaub-thiab-lub raj cua kub exchanger. Qhov no yog ib qho cuab yeej uas ib pob ntawm cov kav dej nyob hauv ib lub tsev (casing), ntxuav los ntawm ntau yam coolants, nyob ntawm seb lub hom phiaj ntawm cov khoom siv. Hauv condensers, piv txwv li, cov tub yees tau khiav mus rau hauv lub plhaub, thiab cov dej ntws mus rau hauv cov hlab. Nrog rau txoj kev tawm xov xwm no, nws yooj yim dua thiab tswj tau zoo duakev ua haujlwm ntawm lub cuab yeej. Hauv cov evaporators, ntawm qhov tsis sib xws, cov tub yees boils hauv cov raj, thaum lawv ntxuav los ntawm cov kua txias (dej, brines, glycols, thiab lwm yam). Yog li ntawd, kev suav ntawm lub plhaub-thiab-lub raj cua kub exchanger yog txo kom txo qhov ntev ntawm cov khoom siv. Ua si nrog lub plhaub txoj kab uas hla, txoj kab uas hla thiab tus naj npawb ntawm cov kav dej sab hauv thiab qhov ntev ntawm lub cuab yeej, tus kws ua haujlwm tau ncav cuag tus nqi ntawm qhov ntsuas kub ntawm qhov chaw sib pauv.
Air heat exchangers
Ib qho ntawm cov khoom siv hluav taws xob ntau tshaj plaws niaj hnub no yog tubular finned heat exchangers. Lawv kuj hu ua nab. Qhov twg lawv tsis tsuas yog ntsia, pib ntawm kiv cua coil units (los ntawm lus Askiv kiv cua + kauj, piv txwv li "ntxuam" + "coil") nyob rau hauv cov chav tsev sab hauv ntawm cov tshuab cais thiab xaus nrog loj heev flue gas recuperators (kub rho tawm los ntawm kub flue roj. thiab xa mus rau cua sov xav tau) hauv boiler nroj tsuag ntawm CHP. Tias yog vim li cas qhov kev suav ntawm coil heat exchanger yog nyob ntawm daim ntawv thov qhov twg cov khoom siv hluav taws xob no yuav mus ua haujlwm. Cov cua txias cua txias (HOPs) tau nruab rau hauv cov nqaij blast freezing chambers, low-temperature freezers thiab lwm yam khoom noj tub yees yuav tsum muaj qee yam qauv tsim hauv lawv cov qauv tsim. Qhov sib nrug ntawm cov lamellas (fins) yuav tsum loj npaum li qhov ua tau txhawm rau txhawm rau ua kom lub sijhawm ua haujlwm tsis tu ncua ntawm cov voj voog defrost. Evaporators rau cov ntaub ntawv chaw (cov chaw ua haujlwm cov ntaub ntawv), ntawm qhov tsis sib xws, yog ua kom compact li sai tau los ntawm clamping lub interlamellar.yam tsawg kawg nkaus. Cov khoom siv hluav taws xob zoo li no ua haujlwm hauv "cov cheeb tsam huv", uas nyob ib puag ncig los ntawm cov ntxaij lim dej zoo (txog HEPA chav kawm), yog li ntawd, xws li kev suav ntawm tubular heat exchanger yog ua los ntawm qhov tseem ceeb ntawm kev txo qhov ntev.
Plate heat exchangers
Tam sim no, phaj kub hloov pauv tau nyob rau hauv kev thov ruaj khov. Raws li lawv tsim, lawv yog kiag li collapsible thiab semi-welded, tooj liab-soldered thiab npib tsib xee-soldered, welded thiab soldered los ntawm diffusion (tsis muaj solder). Kev suav thermal ntawm lub phaj kub hloov pauv yog qhov hloov tau yooj yim thiab tsis muaj qhov nyuaj tshwj xeeb rau tus kws ua haujlwm. Hauv kev xaiv cov txheej txheem, koj tuaj yeem ua si nrog hom phaj, qhov tob ntawm forging raws, hom fins, thickness ntawm cov hlau, cov ntaub ntawv sib txawv, thiab qhov tseem ceeb tshaj plaws, ntau tus qauv-qhov loj me ntawm cov khoom siv sib txawv. Cov khoom siv hluav taws xob zoo li no yog qhov qis thiab dav (rau chav cua sov ntawm cov dej) lossis siab thiab nqaim (kev sib cais cov cua sov rau cov tshuab cua txias). Lawv kuj feem ntau siv rau theem hloov pauv xov xwm, piv txwv li condensers, evaporators, desuperheaters, precondensers, thiab lwm yam. Thermal xam ntawm ob-theem cua sov exchanger yog me ntsis nyuab dua li cov kua-kua hluav taws kub exchanger, txawm li cas los xij, rau cov kws tshaj lij, txoj hauj lwm no daws tau thiab tsis muaj teeb meem tshwj xeeb. Txhawm rau pab txhawb cov kev suav, cov neeg tsim qauv niaj hnub siv engineering computer databases, qhov twg koj tuaj yeem nrhiav ntau cov ntaub ntawv tsim nyog, suav nrog lub xeev daim duab ntawm cov tub yees hauv ib qho cheb, piv txwv li, ib qho kev pab cuam. CoolPack.
Piv txwv ntawm kev ntsuas cua sov
Lub hom phiaj tseem ceeb ntawm kev suav yog xam qhov xav tau ntawm thaj chaw ntawm qhov chaw sib pauv cua sov. Thermal (tub yees) fais fab feem ntau teev nyob rau hauv cov nqe lus ntawm kev siv, txawm li cas los xij, hauv peb qhov piv txwv, peb yuav suav nws, yog li hais, txhawm rau txheeb xyuas cov ntsiab lus ntawm kev siv nws tus kheej. Qee lub sij hawm nws kuj tshwm sim tias qhov yuam kev tuaj yeem nkag mus rau hauv cov ntaub ntawv qhov chaw. Ib txoj haujlwm ntawm tus kws tshaj lij engineers yog nrhiav thiab kho qhov yuam kev no. Ua piv txwv, cia peb suav cov phaj kub hloov pauv ntawm "kua-kua" hom. Cia qhov no ua lub siab tawg hauv lub tsev siab. Txhawm rau tshem tawm cov cuab yeej los ntawm kev siab, qhov no yog feem ntau siv hauv kev tsim cov skyscrapers. Ntawm ib sab ntawm lub tshav kub exchanger, peb muaj dej nrog inlet kub Tin1=14 ᵒС thiab qhov hluav taws xob kub Тout1=9 ᵒС, thiab nrog ib tug txaus tus nqi G1=14,500 kg / h, thiab nyob rau lwm yam - kuj dej, tab sis tsuas nrog rau cov nram qab no tsis: Тin2=8 ᵒС, Тout2=12 ᵒС, G2=18 125 kg/h.
Peb suav qhov xav tau lub zog (Q0) siv cov qauv ntsuas cua sov (saib daim duab saum toj no, qauv 7.1), qhov twg Ср yog lub peev xwm kub tshwj xeeb (tus nqi rooj). Rau kev yooj yim ntawm kev suav, peb muab tus nqi txo ntawm qhov muaj peev xwm kub Срв=4.187 [kJ / kgᵒС]. Kev suav:
Q1=14,500(14 - 9)4, 187=303557. 5 [kJ/h]=84321, 53 W=84. 3 kW - ntawm thawj sab thiab
Q2=18 125(12 - 8)4, 187=303557. 5 [kJ/h]=84321, 53 W=84. 3 kW - sab thib ob.
Nco ntsoov tias, raws li cov qauv (7.1), Q0=Q1=Q2, tsis hais txognyob rau sab twg muab xam.
Ntxiv mus, siv qhov sib npaug ntawm qhov sib npaug ntawm qhov kub hloov pauv (7.2), peb pom thaj chaw uas yuav tsum tau muaj (7.2.1), qhov twg k yog qhov sib npaug ntawm qhov sib npaug ntawm 6350 [W / m 2]), and ΔТav.log. - qhov nruab nrab ntawm qhov sib txawv ntawm logarithmic kub, xam raws li tus qauv (7.3):
ΔT nruab nrab log.=(2 - 1) / ln (2 / 1)=1 / ln2=1 / 0, 6931=1, 4428;
F then=84321 / 63501, 4428=9.2 m2.
Thaum lub tshav kub hloov pauv coefficient tsis paub, kev suav ntawm cov phaj kub hloov pauv yog qhov nyuaj me ntsis. Raws li cov qauv (7.4), peb suav cov qauv Reynolds, qhov twg ρ yog qhov ceev, [kg/m3], η yog dynamic viscosity, [Ns/m 2], v yog qhov nrawm ntawm qhov nruab nrab hauv lub channel, [m / s], d cm yog wetted txoj kab uas hla ntawm channel [m].
Raws li lub rooj, peb nrhiav tus nqi ntawm Prandtl cov qauv [Pr] peb xav tau thiab, siv cov qauv (7.5), peb tau txais cov qauv Nusselt, qhov twg n=0.4 - nyob rau hauv cov xwm txheej ntawm cov kua cua sov, thiab n=0.3 - nyob rau hauv cov dej txias.
Tom ntej no, siv cov qauv (7.6), peb suav cov cua sov hloov coefficient ntawm txhua qhov txias txias rau phab ntsa, thiab siv cov qauv (7.7), peb suav cov cua sov hloov coefficient, uas peb hloov mus rau hauv cov mis (7.2.1) xam qhov chaw ntawm qhov chaw sib pauv cua sov.
Hauv cov qauv qhia, λ yog cov thermal conductivity coefficient, ϭ yog channel phab ntsa thickness, α1 thiab α2 yog cov cua kub hloov coefficients los ntawm txhua tus ntawm cov khoom siv hluav taws xob mus rau phab ntsa.
