Izinto Ezichaphazela Ukusebenza Kwee-Open – Channel Flowmeters

I. Iimeko zeHydraulic

A. Ukuxinana Kokuhamba Komoya

Ukuhamba okuguquguqukayo yingxaki eqhelekileyo kwiinkqubo zemijelo evulekileyo. Xa ukuhamba kungqubana, isantya solwelo siyahluka ngokungacwangciswanga ngobukhulu nangokwecala kulo lonke icala lomjelo.Iimitha zokuhamba zetshaneli ezivulekileyo, ingakumbi ezo zixhomekeke kwiindlela zesantya - indawo (ezifana ne-ultrasonic okanye i-electromagnetic open - channel flowmeters), zicinga ukuba iprofayili yokuhamba ezinzileyo neqikelelweyo yokulinganisa ngokuchanekileyo. I-Turbulence iyayiphazamisa le ngcamango. Umzekelo, emlanjeni onezantsi elirhabaxa okanye kumjelo onotshintsho olukhawulezileyo kwi-geometry, ukwakheka kwee-eddies kunye nee-swirls kunokubangela ukuba isantya sokuhamba kwiindawo ezahlukeneyo sihluke kakhulu kwixabiso eliqhelekileyo elilindelwe yi-flowmeter. Ngenxa yoko, isantya esilinganisiweyo sinokungameli ngokuchanekileyo isantya sokuhamba sisonke, nto leyo ekhokelela ekufundweni okungachanekanga.

B. Utshintsho kubunzulu bokuhamba kwamanzi

Ukuguquguquka kobunzulu bokuhamba kwamanzi nako kunokubangela iingxakiii-flowmeters zetshaneli ezivulekileyo. Ii-flowmeters ezininzi, ezifana nee-weirs kunye ne-flumes, zenzelwe ukulinganisa isantya sokuhamba kwamanzi ngokusekelwe kulwalamano oluthile phakathi kobunzulu bokuhamba kwamanzi kunye nokuphuma kwamanzi. Ukuba ubunzulu bokuhamba butshintsha ngokukhawuleza okanye ngokungangqalanga, olu lwalamano lusenokungabi yinyani. Kwiinkqubo zokuhambisa amanzi emvula, umzekelo, imvula enkulu ngequbuliso inokubangela ukwanda okukhulu kobunzulu bokuhamba kwamanzi. Ukuba i-flowmeter ayilinganiswanga ukuze ichaze utshintsho olukhawulezayo nolukhulu kubunzulu, isenokubala kakubi isantya sokuhamba kwamanzi. Ukongeza, ubukho bamaza okanye ukunyuka kwamanzi kwitshaneli kunokwenza kube nzima ngakumbi ukulinganisa ubunzulu bokuhamba kwamanzi, njengoko i-flowmeter inokurekhoda amaxabiso obunzulu angahambelaniyo, okubangela ukubalwa kwesantya sokuhamba kwamanzi kungachanekanga.

II. Iimpawu zeChannel

A. Ukungalungi kweSiteshi

Iitshaneli zendalo zihlala zinemilo engacwangciswanga, enobubanzi, ubunzulu, kunye namathambeka ahlukeneyo. Iitshaneli ezenziwe ngabantu nazo zinokubangela ukungalungelelani ngokuhamba kwexesha ngenxa yokubola kwenkunkuma, ukukhukuliseka, okanye umonakalo wesakhiwo.Iimitha zokuhamba zetshaneli ezivulekileyozihlala zilinganiswa ngokweejiometri zetshaneli eziqhelekileyo neziqhelekileyo. Xa zifakelwe kwiitshaneli ezineenxalenye ezinqamlezileyo ezingangqalanga, ukusasazwa kokuhamba kwamanzi kuba yinto engalinganiyo, kwaye i-flowmeter isenokungakwazi ukulinganisa ngokuchanekileyo isantya esiphakathi okanye indawo enqamlezileyo. Umzekelo, kumjelo apho inkunkuma iqokelelene khona kwelinye icala, ukuhamba kwamanzi kuya kujikajika, kwaye i-flowmeter isenokudlula okanye inciphise isantya sokuhamba kwamanzi kuxhomekeke kwindawo yayo ngaphakathi kwitshaneli.

B. Uburhabaxa bomphezulu

Uburhabaxa bomphezulu wetshaneli buchaphazela ukumelana nokuhamba kwamanzi kunye nokusasazwa kwesantya ngaphakathi kwetshaneli. Umphezulu orhabaxa, ofana nowetshaneli egqunywe ngamatye okanye kumjelo wendalo onamatye kunye nezityalo, ubangela ukungqubana okungakumbi njengoko ulwelo luhamba. Olu ngqubano lunciphisa isantya sokuhamba kwamanzi kufutshane nemida yetshaneli kwaye lunokukhokelela kwiprofayili yesantya esingeyiyo i-logarithmic, eyahlukileyo kwiprofayili efanelekileyo ecingelwa ngabaninzi.umlinganiselo wokuhamba komjelo ovulekileyoiindlela. Iiflowmeters ezixhomekeke ekucingeni iprofayili yesantya esithile, njengee-ultrasonic Doppler flowmeters, zinokuvelisa iziphumo ezingachanekanga xa uburhabaxa bomphezulu wetshaneli bungabalwanga kakuhle. Ukwanda koburhabaxa bomphezulu kunokubangela ingxubakaxaka eyongezelelweyo, nto leyo enokwenza kube nzima ngakumbi inkqubo yokulinganisa ukuhamba.

III. Ukuphazamiseka Kwangaphandle

A. Iinkunkuma kunye nemifuno

Inkunkuma, efana namasebe, amagqabi, kunye nenkunkuma, kunye nezityalo ezikhule kakhulu ngaphakathi okanye ezijikeleze umjelo, zinokuphazamisana nokusebenzaii-flowmeters zetshaneli ezivulekileyo. Kwi-ultrasonic flowmeters, inkunkuma kunye nezityalo zinokuvala indlela yemiqondiso ye-ultrasound, nokuba ngokufunxa okanye ukubonakalisa amaza. Oku kuphazamiseka kunokukhokelela ekufumaneni isignali ngendlela engalunganga kunye nokutolikwa gwenxa kwesantya sokuhamba. Kwimeko ye-mechanical flowmeters, njenge-propeller - type flowmeters, inkunkuma inokubanjwa kwiindawo ezihambayo, okubangela ukuba imitha ixinane okanye ijikeleze ngesantya esingalunganga. Ukukhula kwezityalo kufutshane nomphezulu wamanzi nako kunokuchaphazela ukulinganiswa kobunzulu bokuhamba, njengoko kunokudala ujongano olungalinganiyo lwamanzi nomoya oludibanisa izixhobo zokuva ubunzulu.

B. Izinto eziphathelele indalo

Izinto ezingqongileyo ezifana nemimoya enamandla kunye nokutshintsha kobushushu zinokuchaphazelai-flowmeter yetshaneli evulekileyoukusebenza. Imimoya enamandla ingenza amaza kumphezulu wamanzi kwiindlela ezivulekileyo. La maza anokubangela ukuguquguquka kubunzulu bokuhamba okulinganisiweyo, ingakumbi kwiinzwa ezixhomekeke ekufumaneni umgangatho womphezulu. Utshintsho lobushushu lunokuchaphazela iimpawu zomzimba zolwelo, njengobuninzi balo kunye ne-viscosity. Kwii-flowmeters ezisebenzisa isantya sesandi kulwelo ukulinganisa (umz., ii-ultrasonic flowmeters), utshintsho kubushushu bolwelo lunokutshintsha isantya sesandi, nto leyo ekhokelela kwiimpazamo ekulinganisweni kwesantya. Kwiimozulu ezibandayo, ukwakheka komkhenkce kwindlela nakho kunokubangela ingxaki enkulu, njengoko kunokuthintela i-flowmeter okanye kutshintshe iimpawu zokuhamba ngaphakathi kwindlela.

Ukuqukumbela, izinto ezahlukeneyo ezinxulumene neemeko ze-hydraulic, iimpawu zetshaneli, kunye nokuphazamiseka kwangaphandle zinokubangelaii-flowmeters zetshaneli ezivulekileyoukubonelela ngemilinganiselo engachanekanga. Ukuqonda nokujongana nale miba kubalulekile ukuqinisekisa ukusebenza okuthembekileyo kweenkqubo zokulinganisa ukuhamba komjelo ovulekileyo.