Imigaqo yeBERNOULLI-Imithambo

Isazinzulu, uDaniel Bernoulli, wakhula ngo-1738, umthetho-siseko onegama lakhe, obeka ubudlelwane besantya samanzi kunye noxinzelelo olukhoyo, xa ulwelo luhamba. Ulwelo luthanda ukukhawulezisa kwimibhobho emxinwa.

Ikwacebisa ukuba, kulwelo olushukumayo, amandla aguqulwa ngalo lonke ixesha indawo enqamlezileyo yombhobho itshintsha, ibonisa iBernoulli Equation, ubudlelwane bemathematika phakathi kweendlela zamandla eziboniswa lulwelo oluhambayo.

Ukusetyenziswa komgaqo weBernoulli uneentlobo ngeentlobo zamakhaya, ezentengiso kunye nezicelo zorhwebo, ezinje ngeetshimini, ukutshiza izinambuzane, iimitha zokuhamba, iityhubhu zeVenturi, iicarburettors, iikomityi zokutsala, ukuphakamisa inqwelomoya, iiozonators zamanzi, izixhobo zamazinyo, phakathi kwabanye. Yisiseko sokufunda i-hydrodynamics kunye ne-fluid mechanics.

IINGQONDO EZISISISEKO ukuqonda iMigaqo kaBernoulli

NdibamemileMasibone inqaku le- Ubushushu boMthetho kaJoule "Izicelo-zoQeqesho"

Ulwelo:

Iseti yeemolekyuli ezabiwe ngokungacwangciswanga ezigcinwe ngokudibeneyo kunye nemikhosi enyanzeliswa ziindonga zesikhongozeli, ngaphandle kwevolumu echaziweyo. Zombini ulwelo kunye neegesi zithathwa njengamanzi. Kwisifundo sokuziphatha kweencindi, ukufundwa kolwelo kwindawo yokuphumla (i-hydrostatic) kunye neencindi zamanzi ezihambayo (i-hydrodynamics) zihlala ziqhutywa. Jonga umzobo 1.

Siyakumema ukuba ubone eli nqaku Imigaqo ye-Thermodynamic

Ubunzima:

Umlinganiso we-inertia okanye ukuxhathisa ukutshintsha ukuhamba komzimba onamanzi. Ukulinganisa ubungakanani bolwelo, bulinganiswa nge-kg.

Ubunzima:

Amandla apho ulwelo lutsala emhlabeni ngesenzo somxhuzulane. Ilinganiswa ngo-N, lbm.ft / s².

Ukuxinana:

Inani lobunzima kwiyunithi yevolumu yento. Ilinganiswa nge-kg / m³.

Ukuhamba:

Umthamo ngeyunithi yexesha, kwi-m3 / s.

Uxinzelelo:

Inani lamandla afunyenwe kwindawo yento ethile, okanye ngaphezulu. Ilinganiswa ngePascal okanye ipsi, phakathi kwezinye iiyunithi.

I-viscisiti:

Ukuchasana kwamanzi okuhamba, ngenxa yokungqubana kwangaphakathi. Ukuphakama kwe-viscosity, kokuhla ukuhamba. Iyahluka ngoxinzelelo kunye nobushushu.

UMthetho woLondolozo lwaMandla:

Amandla awenziwanga okanye atshatyalaliswe, aguqulwa abe lolunye uhlobo lwamandla.

Ukuqhubeka kokulingana:

Kwipayipi enobubanzi obahlukeneyo, ukuhamba rhoqo, kukho ubudlelwane phakathi kweendawo kunye nesantya samanzi. Izantya zilingana ngokuchaseneyo nemimandla enqamlezileyo yombhobho. [1]. Jonga umzobo 2.

Umgaqo kaBernoulli

Ingxelo yoMgaqo-siseko kaBernoulli

Umgaqo kaBernoulli umisela ubudlelwane phakathi kwesantya kunye noxinzelelo lolwelo oluhambayo. Umgaqo kaBernoulli uthi, xa ushukuma ulwelo, njengoko isantya sokonyuka kolwelo sikhula, uxinzelelo luyancipha. Amanqaku esantya esiphezulu aya kuba noxinzelelo oluncinci. [Mbini]. Jonga umfanekiso 2.

Xa ulwelo luhamba ngombhobho, ukuba umbhobho unonciphiso (ubukhulu obuncinci), ulwelo kufuneka lonyuse isantya salo ukugcina ukuhamba, kunye noxinzelelo lwayo luyancipha. Jonga umfanekiso 4.

Ukusetyenziswa koMgaqo-siseko kaBernoulli

IsiBeki:

Isixhobo, kwiinjini ezihamba ngepetroli, apho kuxutywa khona umoya kunye nepetroli. Njengoko umoya udlula kwi-valve yokunyusa, uxinzelelo lwayo luyancipha. Ngokwehla koxinzelelo ipetroli iqala ukuhamba, kuxinzelelo oluphantsi kangaka iyaphefumla kwaye ixubeke nomoya. [3]. Jonga umfanekiso 5.

Iiplanethi:

Ukubhabha kwenqwelomoya, amaphiko ayilelwe ukwenzela ukuba kuveliswe amandla abizwa ngokuba "kukuphakamisa", oko kwenza umahluko woxinzelelo phakathi kwenxalenye ephezulu neyezantsi yamaphiko. Kumzobo 6 ungabona enye yoyilo lwamaphiko enqwelomoya. Umoya ogqitha phantsi kwephiko lenqwelomoya uthambekele ekwahlukaniseni ukudala uxinzelelo olukhulu, ngelixa umoya ogqitha kwiphiko uhamba umgama omkhulu nesantya esikhulu. Kuba uxinzelelo oluphezulu luphantsi kwephiko, amandla okuphakamisa aqhubela iphiko phezulu.

Umqhubi wenqanawa:

Sisixhobo esisetyenziswa njengesixhobo sokuhambisa iinqanawa. Iipropeleri zinoluhlu lweebhleyidi ezenzelwe ukuba xa i-propeller ijikeleza, umahluko wesantya uveliswa phakathi kobuso beelayi, kwaye ke ngenxa yoko umahluko woxinzelelo (isiphumo seBernoulli). Al. Umahluko woxinzelelo uvelisa amandla, ngokungafaniyo nenqwelomoya, eqhubela isikhephe. Jonga umfanekiso 7.

Ukuqubha:

Xa ushukumisa izandla zakho xa uqubha, kukho umahluko woxinzelelo phakathi kwesundu kunye nomva wesandla. Kwintende yesandla, amanzi adlula ngesantya esisezantsi kunye noxinzelelo oluphezulu (umthetho-siseko kaBernoulli), ovela "kumandla okuphakamisa" axhomekeke kumahluko woxinzelelo phakathi kwesundu kunye nomva wesandla. Jonga umzobo 8.

Ukulingana komgaqo kaBernoulli

Ubalo lukaBernoulli lusivumela ukuba sihlalutye imathematika xa sihamba. Umgaqo kaBernoulli uvela, ngokwezibalo, ngokusekwe kulondolozo lwamandla, esithi amandla awenziwanga okanye atshatyalaliswe, aguqulwa abe lolunye uhlobo lwamandla. I-Kinetic, amandla kunye nokuhamba kwamandla kujongwa:

• Iikinetiki: exhomekeke kwisantya kunye nobunzima bolwelo
• Izinto ezinokwenzeka: ngenxa yokuphakama, ngokunxulumene nenqanaba lesalathiso
• Ukuhamba okanye uxinzelelo: amandla athwalwa ziimolekyuli zolwelo xa zihamba kumbhobho. Jonga umfanekiso 9.

Amandla apheleleyo okushukuma okuhamba sisibalo samandla oxinzelelo lokuhamba, amandla e-kinetic kunye namandla anokubakho. NgokomThetho woLondolozo lwaMandla, amandla elwelo ngombhobho alingana nokungena kunye nokuphuma. Isixa samandla kwindawo yokuqala, kwindawo yokungena yombhobho, ilingana nesixa samandla esiphuma. [1]. Jonga umzobo 10.

Imiqobo yeBernoulli Equation

• Isebenza kuphela kulwelo olungenakuthelekiswa nanto.
• Ayithathi ingqalelo izixhobo ezongeza amandla kwinkqubo.
• Utshintsho lobushushu aluthathelwa ngqalelo (kubalo olusisiseko).
• Izinto zomhlaba azithathelwa ngqalelo (Akukho zilahleko zochuku).

Ukuzivocavoca

Ukuzisa amanzi kumgangatho wesibini wendlu, kusetyenziswa umbhobho ofana nalo uboniswe kumfanekiso 11. Kuyanqweneleka ukuba, ekuphumeni kombhobho, okufumaneka kwiimitha ezi-3 ngaphezulu komhlaba, amanzi anesantya se-5 m. / s, ngoxinzelelo olingana ne-50.000 Pa. Kufuneka ibe yintoni isantya noxinzelelo apho amanzi kufuneka empontshwe khona? Kumzobo we-10 ukungena kwamanzi kuphawulwe njenge-1 kunye nendawo yokuphuma kwamanzi kumbhobho omncinci njenge-point 2.

Solution

Ukufumanisa i-velocity v1, ukuqhubekeka kokulingana kusetyenziswa indawo yokungena yombhobho. Jonga umzobo 12.

Ubalo lweBernoulli luya kusetyenziselwa ukubala uxinzelelo kwindawo yokungena P1, njengoko kubonisiwe kumfanekiso we-13.

Izigqibo Umgaqo kaBernoulli

Umgaqo kaBernoulli uthi, kulwelo olushukumayo, xa isantya salo sisanda, isantya soxinzelelo esisezantsi. Amandla aguqulwa ngalo lonke ixesha indawo enqamlezileyo yombhobho itshintsha.

Ubalo lukaBernoulli sisiphumo solondolozo lwamandla kulwelo olushukumayo. Ithi isambuku soxinzelelo lolwelo, amandla e-kinetic kunye namandla anokubakho, ahlala ehleli rhoqo kuyo yonke indlela yolwelo.

Lo mthetho-siseko unokusetyenziswa okuninzi njengokuphakanyiswa kweenqwelomoya, okanye komntu xa edada, kunye noyilo lwezixhobo zothutho lwamanzi, phakathi kweminye emininzi, ukufundwa kwayo kunye nokuqonda kubaluleke kakhulu.

IZALATHISO

[1] Mott, URobert. (2006). Ubuchwephesha bolwelo. Uhlobo lwe-6. Imfundo yePearson
[2]
[3]