Izinto Eziphathelene Noketshezi Oluqinile Nolunamandla
I-Fluid mechanics, enye yamagatsha ayisisekelo ku-continuum mechanics, iyinsimu efunda ukuziphatha koketshezi (uketshezi namagesi) kuzo zombili izimo ezimile nezishintshashintshayo. Ukuhlukaniswa kube yizimo ezimile (uketshezi oluphumulile) kanye nezimo eziguquguqukayo (uketshezi oluhambayo) kuvumela ukuqonda okuhlelekile kokuthi uketshezi lusebenzisana kanjani namandla nokuthi izakhiwo zawo zomzimba zibonakala kanjani ngaphansi kwezimo ezahlukene. Lesi sihloko sihlola izimiso ezibalulekile zoketshezi ezimweni ezimile nezishintshashintshayo, sihlola izakhiwo zazo, silawula izibalo, kanye nezinhlelo zokusebenza zangempela.
Izakhiwo Zoketshezi
Izakhiwo Eziyisisekelo
– Ubuningi (ρ): Ubuningi buyisisindo ngeyunithi ngayinye yevolumu yoketshezi. Kuyisici esiyisisekelo esithonya ukuziphatha koketshezi kokubili ezimweni ezimile nezishintshashintshayo.
– Ukuqina (η): Ukuqina kuyisilinganiso sokumelana koketshezi ekuguqukeni. Kulinganisa ukungqubuzana kwangaphakathi ngaphakathi koketshezi. Ukuqina kuthonya amaphethini okugeleza kanye nokuhlakazeka kwamandla kuketshezi olushintshashintshayo.
– Ukucindezela (P): Ukucindezela amandla asetshenziswa endaweni ngayinye ngaphakathi koketshezi, okubalulekile kokubili kuma-hydrostatics kanye nama-hydrodynamics.
Izakhiwo ezingeziwe
– Ukucindezeleka Komphezulu: Lokhu kungamandla ahlanganayo ebusweni boketshezi, okuthinta izimo ezifana nokwakheka kwe-capillarity kanye nokwakheka kwamaconsi.
– Ukucindezeleka: Nakuba uketshezi luvame ukungacindezeleki, amagesi abonisa ukwehluka okukhulu kobuningi ngaphansi kwezingcindezi ezahlukene.
– Ukushisa Okushisayo: Lesi sici sibalulekile ekuqondeni ukudluliselwa kokushisa koketshezi, kubalulekile kokubili ezinqubweni zemvelo nezezimboni.
Amanzi Angaguquki
Ama-Hydrostatics
I-Hydrostatics isifundo soketshezi oluphumulile. Ukugxila okuyinhloko ukuqonda ukusatshalaliswa kwengcindezi ngaphakathi koketshezi nokuthi amandla angaphandle, njengokudonsa phansi, athonya kanjani lokhu kusatshalaliswa.
I-Hydrostatic Pressure
Ingcindezi ye-hydrostatic inikezwa yi:
\[ P = \rho gh + P_0 \]
kuphi:
– \( P \) ingcindezi ekujuleni \( h \).
– \( \rho \) ukuminyana koketshezi.
– \( g \) ukusheshisa okubangelwa amandla adonsela phansi.
– \( P_0 \) ingcindezi yomoya ebusweni boketshezi.
Lesi sibalo sibonisa ukuthi ingcindezi iyanda ngokuhambisana nokujula kwekholomu yoketshezi. Lesi simiso siyisisekelo sokuqonda izenzakalo ezifana nokuntanta kanye nokwakhiwa kwezakhiwo eziqukethe uketshezi ezifana namadamu nemikhumbi-ngwenya.
I-Buoyancy
Isimiso sika-Archimedes sithi umzimba ocwiliswe oketshezini uzwa amandla okuphapha alingana nesisindo soketshezi olususiwe. Ukuqina kubalulekile ekwakhiweni kwemikhumbi nasekuqondeni ukuzinza kwezinto ezintantayo. Amandla okuphapha \(F_b \) angachazwa kanje:
\[ F_b = \rho V g \]
Lapho \( V \) kuyivolumu yoketshezi olususiwe.
Ama-Dynamic Fluids
I-Fluid Dynamics
I-fluid dynamics ihilela ukutadisha uketshezi oluhambayo. Ihlanganisa imikhakha ehlukahlukene engaphansi, okuhlanganisa i-aerodynamics kanye ne-hydrodynamics, kanye nezinhlelo zokusebenza ezisukela ekwakhiweni kwezindiza kuya kubunjiniyela bepayipi.
Izilinganiso zika-Euler no-Navier-Stokes
Ukunyakaza koketshezi kungachazwa ngezibalo zika-Euler zoketshezi olufanele (olungaqinile) kanye nezibalo zika-Navier-Stokes zoketshezi oluqinile.
- Isibalo sika-Euler:
\[ \frac{\partial \mathbf{u}}{\partial t} + (\mathbf{u} \cdot \nabla)\mathbf{u} = -\frac{1}{\rho} \nabla P + \mathbf{f} \]
- Isibalo seNavier-Stokes:
\[ \rho \left( \frac{\partial \mathbf{u}}{\partial t} + (\mathbf{u} \cdot \nabla)\mathbf{u} \right) = -\nabla P + \mu \nabla^2 \mathbf{u} + \mathbf{f} \]
Lapho \( \mathbf{u} \) kuyinsimu yejubane, \( P \) kuyingcindezi, \( \mu \) kuyi-viscosity eguquguqukayo, kanye \( \mathbf{f} \) imelela amandla omzimba, njengokudonsa phansi.
Ukugeleza Okunezivunguvungu Nokuxokozela
– Ukugeleza kweLaminar: Kubonakaliswa yizingqimba zoketshezi ezibushelelezi nezihlelekile ezinokuxuba okuncane. Kuchazwa ngenombolo ephansi kaReynolds (\( Re \)), futhi ijubane lokugeleza liyafana. Isibonelo ukugeleza koju.
– Ukugeleza Okuguquguqukayo: Kubonakaliswa ukunyakaza koketshezi okungahlelekile, okuphazamisekile okuxubene kakhulu. Lokhu kwenzeka ngezinombolo eziphezulu zikaReynolds. Ukugeleza okuguquguqukayo kuvamile emanzini emvelo nasezinqubweni zezimboni.
Isimiso sikaBernoulli
Isimiso sikaBernoulli siwumqondo oyisisekelo ekushintsheni koketshezi, okuhlobene nokucindezela kanye nesivinini kuketshezi oluhambayo. Sithi ukwanda kwesivinini soketshezi kwenzeka ngesikhathi esisodwa nokwehla kwengcindezi noma amandla angaba khona. Isibalo sikaBernoulli sokugeleza okungacindezeleki yilesi:
\[ P + \frac{1}{2} \rho u^2 + \rho gh = \text{constant} \]
Lesi simiso siyisisekelo ekuchazeni izenzakalo ezifana nokuphakanyiswa kwamaphiko endiza kanye nomphumela weVenturi.
I-Computational Fluid Dynamics (CFD)
I-CFD iyinkambu esebenzisa ukuhlaziywa kwezinombolo kanye nama-algorithms ukuxazulula nokuhlaziya izinkinga ezihilela ukugeleza koketshezi. Besebenzisa ama-supercomputer, onjiniyela kanye nososayensi bangalingisa ukusebenzisana koketshezi okuyinkimbinkimbi ezimweni ezahlukahlukene, bathuthukise imiklamo yezinhlelo ezisukela ezimotweni zezemidlalo kuya kumamodeli emvelo.
Ukusetshenziswa Kwemishini Yoketshezi
Ubunjiniyela nobuchwepheshe
I-fluid mechanics ibalulekile ezinhlotsheni eziningi zobunjiniyela. Izimiso ze-hydrostatics kanye ne-fluid dynamics zisetshenziswa ku:
– Ubunjiniyela Bezokwakha: Amadamu, izinhlelo zokusabalalisa amanzi, kanye nezinhlelo zokulahla indle.
– Ubunjiniyela Bezindiza: Ukuklama izindiza, izinhlelo zokuqhuba amarokhethi, kanye ne-aerodynamics.
– Ubunjiniyela Bemishini: Izinhlelo ze-HVAC, ama-turbine, amaphampu, kanye nemiklamo yezimoto.
– Ubunjiniyela Basemanzini: Ukwakhiwa kwemikhumbi, ukuklama imikhumbi-ngwenya, kanye nezakhiwo zasemanzini.
Isayensi yezemvelo
Ukuqonda ukuziphatha koketshezi kubalulekile kwisayensi yezemvelo ukuze kuboniswe imisinga yolwandle, kubikezelwe amaphethini ezulu, futhi kuphathwe izinsiza zamanzi. Izifundo zamanzi zithembele kakhulu kumishini yoketshezi ukuze kubikezelwe izikhukhula kanye nokuphatha amachibi.
Medicine
Izimiso ze-fluid mechanics ziyasebenza emzimbeni womuntu, ikakhulukazi ekuqondeni ukugeleza kwegazi kanye ne-respiration mechanics. Lolu lwazi lusiza ekwakheni amadivayisi ezokwelapha njengenhliziyo yokwenziwa kanye ne-ventilator.
Isiphetho
Ucwaningo lwe-static kanye ne-dynamic fluid luhlanganisa indawo enkulu nebalulekile ye-physics kanye nobunjiniyela, enezimiso ezibalulekile kuzo zonke izinhlelo zokusebenza emikhakheni ehlukene. Izakhiwo eziyisisekelo kanye nezibalo ezilawulayo zinikeza uhlaka oluqinile lokubikezela nokulawula ukuziphatha kwe-fluid ezindaweni ezahlukene, kusukela ezindaweni zemvelo kuya ezinqubweni zezimboni eziyinkimbinkimbi. Kungakhathaliseki ukuthi ukuklama izakhiwo eziphephile, izimoto ezisebenza kahle kakhulu, noma amadivayisi ezokwelapha athuthukile, ukuqonda okutholakala ku-fluid mechanics kuqhuba ukusungula izinto ezintsha kanye nokuqonda kokubili ezinhlelweni zemvelo kanye nezakhiwe.
