Numerička simulacija strujnog polja vazduha u nadzvučnom mlazniku sa preprekom na izlazu
Computational simulation of air flow supersonic nozzle with obstacle at exit
2016
Authors
Kostić, OliveraContributors
Stefanović, ZoranStupar, Slobodan
Simonović, Aleksandar
Gvozdenović, Slobodan
Miloš, Marko
Doctoral thesis (Published version)
Metadata
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U ovom radu se razmatra uticaj sklopnih operacija na izolacione karakteristike vakuumskih sklopnih elemenata. Razmatraju se sledeće sklopne operacije: uklop bez struje – isklop bez struje, uklop bez struje - uklop sa nominalnom strujom, uklop bez struje - isklop sa strujom kratkog spoja. Pri tome se ovaj uticaj ispituje na slučajne veličine ac probojni napon, impulsni probojni napon i na pretprobojne parametre V-4,V-5 i V-6 (dc naponi pri kojima je pretprobojna struja 10-4 A, 10-5 A i 10-6 A). Dobijeni efekti promene karakteristika nakon sklopnih operacija se porede sa odgovarajućim rezultatima dobijenim sa istim skopnim elementima kondicioniranih kontakata. Tako dobijeni rezultati se tumače preko mehanizma elektičnog pražnjenja u vakuumu. Osnovni rezultat, a ujedno i cilj rada, je ispitivanje relacija korelacije i regresije između eksperimentalno dobijenim statističkim uzorcima slučajne veličine ac i impulsni probojni napon i njima odgovarajućih statističkih uzoraka slučajnih veličina... predprobojnih parametara V-4,V-5 i V-6. Ispitivanje se vrši na komercijalnim vakuumskim sklopnim elementima sa CuCr i CuBi kontaktima.
This work considers the influence of switching operations on the insulating characteristics of vacuum circuit breakers. The following operations, all with circuit-making without current, have been taken into account: circuit-breaking without current, circuit-breaking with nominal current and circuit-breaking with short-circuit current. The influence of switching operations is examined for the random variables breakdown voltage (ac and pulse) and the prebreakdown parameters V-4, V-5, and V-6. Parameters V-4, V-5, and V-6 represent the dc voltage at which the pre-breakdown current takes values of 10-4, 10-5, and 10-6 A, respectively. Switching element characteristics after the switching operations are compared with the corresponding results obtained for switching element with conditioned contacts. Obtained results are analyzed through mechanisms of electrical discharges in vacuum. The main result is an examination of the correlation and regression between the experimentally obtained brea...kdown voltage (ac and pulse) random variable and its corresponding pre-breakdown parameters V-4, V-5, and V-6, respectively. Statistical samples created by using this method do not require the repetition of switching operations and therefore the dielectric strength of the vacuum insulation is kept in its initial state. The examination is carried out on commercial vacuum switching elements with CuCr and CuBi contacts.
Keywords:
vakuumski sklopni elementi / sklopne operacije / regresija / probojni napon / pretprobojni parametar / korelacija / Vacuum switching element / switching operation / regression / pre-breakdown parameter / correlation / breakdown voltageSource:
2016Publisher:
- Univerzitet u Beogradu, Mašinski fakultet
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http://eteze.bg.ac.rs/application/showtheses?thesesId=4151https://nardus.mpn.gov.rs/handle/123456789/7005
https://fedorabg.bg.ac.rs/fedora/get/o:13748/bdef:Content/download
https://fedorabg.bg.ac.rs/fedora/get/o:13912/bdef:Izvestaj/download
http://vbs.rs/scripts/cobiss?command=DISPLAY&base=70036&RID=514771619
https://machinery.mas.bg.ac.rs/handle/123456789/44
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Mašinski fakultetTY - THES AU - Kostić, Olivera PY - 2016 UR - http://eteze.bg.ac.rs/application/showtheses?thesesId=4151 UR - https://nardus.mpn.gov.rs/handle/123456789/7005 UR - https://fedorabg.bg.ac.rs/fedora/get/o:13748/bdef:Content/download UR - https://fedorabg.bg.ac.rs/fedora/get/o:13912/bdef:Izvestaj/download UR - http://vbs.rs/scripts/cobiss?command=DISPLAY&base=70036&RID=514771619 UR - https://machinery.mas.bg.ac.rs/handle/123456789/44 AB - U ovom radu se razmatra uticaj sklopnih operacija na izolacione karakteristike vakuumskih sklopnih elemenata. Razmatraju se sledeće sklopne operacije: uklop bez struje – isklop bez struje, uklop bez struje - uklop sa nominalnom strujom, uklop bez struje - isklop sa strujom kratkog spoja. Pri tome se ovaj uticaj ispituje na slučajne veličine ac probojni napon, impulsni probojni napon i na pretprobojne parametre V-4,V-5 i V-6 (dc naponi pri kojima je pretprobojna struja 10-4 A, 10-5 A i 10-6 A). Dobijeni efekti promene karakteristika nakon sklopnih operacija se porede sa odgovarajućim rezultatima dobijenim sa istim skopnim elementima kondicioniranih kontakata. Tako dobijeni rezultati se tumače preko mehanizma elektičnog pražnjenja u vakuumu. Osnovni rezultat, a ujedno i cilj rada, je ispitivanje relacija korelacije i regresije između eksperimentalno dobijenim statističkim uzorcima slučajne veličine ac i impulsni probojni napon i njima odgovarajućih statističkih uzoraka slučajnih veličina predprobojnih parametara V-4,V-5 i V-6. Ispitivanje se vrši na komercijalnim vakuumskim sklopnim elementima sa CuCr i CuBi kontaktima. AB - This work considers the influence of switching operations on the insulating characteristics of vacuum circuit breakers. The following operations, all with circuit-making without current, have been taken into account: circuit-breaking without current, circuit-breaking with nominal current and circuit-breaking with short-circuit current. The influence of switching operations is examined for the random variables breakdown voltage (ac and pulse) and the prebreakdown parameters V-4, V-5, and V-6. Parameters V-4, V-5, and V-6 represent the dc voltage at which the pre-breakdown current takes values of 10-4, 10-5, and 10-6 A, respectively. Switching element characteristics after the switching operations are compared with the corresponding results obtained for switching element with conditioned contacts. Obtained results are analyzed through mechanisms of electrical discharges in vacuum. The main result is an examination of the correlation and regression between the experimentally obtained breakdown voltage (ac and pulse) random variable and its corresponding pre-breakdown parameters V-4, V-5, and V-6, respectively. Statistical samples created by using this method do not require the repetition of switching operations and therefore the dielectric strength of the vacuum insulation is kept in its initial state. The examination is carried out on commercial vacuum switching elements with CuCr and CuBi contacts. PB - Univerzitet u Beogradu, Mašinski fakultet T1 - Numerička simulacija strujnog polja vazduha u nadzvučnom mlazniku sa preprekom na izlazu T1 - Computational simulation of air flow supersonic nozzle with obstacle at exit UR - https://hdl.handle.net/21.15107/rcub_nardus_7005 ER -
@phdthesis{ author = "Kostić, Olivera", year = "2016", abstract = "U ovom radu se razmatra uticaj sklopnih operacija na izolacione karakteristike vakuumskih sklopnih elemenata. Razmatraju se sledeće sklopne operacije: uklop bez struje – isklop bez struje, uklop bez struje - uklop sa nominalnom strujom, uklop bez struje - isklop sa strujom kratkog spoja. Pri tome se ovaj uticaj ispituje na slučajne veličine ac probojni napon, impulsni probojni napon i na pretprobojne parametre V-4,V-5 i V-6 (dc naponi pri kojima je pretprobojna struja 10-4 A, 10-5 A i 10-6 A). Dobijeni efekti promene karakteristika nakon sklopnih operacija se porede sa odgovarajućim rezultatima dobijenim sa istim skopnim elementima kondicioniranih kontakata. Tako dobijeni rezultati se tumače preko mehanizma elektičnog pražnjenja u vakuumu. Osnovni rezultat, a ujedno i cilj rada, je ispitivanje relacija korelacije i regresije između eksperimentalno dobijenim statističkim uzorcima slučajne veličine ac i impulsni probojni napon i njima odgovarajućih statističkih uzoraka slučajnih veličina predprobojnih parametara V-4,V-5 i V-6. Ispitivanje se vrši na komercijalnim vakuumskim sklopnim elementima sa CuCr i CuBi kontaktima., This work considers the influence of switching operations on the insulating characteristics of vacuum circuit breakers. The following operations, all with circuit-making without current, have been taken into account: circuit-breaking without current, circuit-breaking with nominal current and circuit-breaking with short-circuit current. The influence of switching operations is examined for the random variables breakdown voltage (ac and pulse) and the prebreakdown parameters V-4, V-5, and V-6. Parameters V-4, V-5, and V-6 represent the dc voltage at which the pre-breakdown current takes values of 10-4, 10-5, and 10-6 A, respectively. Switching element characteristics after the switching operations are compared with the corresponding results obtained for switching element with conditioned contacts. Obtained results are analyzed through mechanisms of electrical discharges in vacuum. The main result is an examination of the correlation and regression between the experimentally obtained breakdown voltage (ac and pulse) random variable and its corresponding pre-breakdown parameters V-4, V-5, and V-6, respectively. Statistical samples created by using this method do not require the repetition of switching operations and therefore the dielectric strength of the vacuum insulation is kept in its initial state. The examination is carried out on commercial vacuum switching elements with CuCr and CuBi contacts.", publisher = "Univerzitet u Beogradu, Mašinski fakultet", title = "Numerička simulacija strujnog polja vazduha u nadzvučnom mlazniku sa preprekom na izlazu, Computational simulation of air flow supersonic nozzle with obstacle at exit", url = "https://hdl.handle.net/21.15107/rcub_nardus_7005" }
Kostić, O.. (2016). Numerička simulacija strujnog polja vazduha u nadzvučnom mlazniku sa preprekom na izlazu. Univerzitet u Beogradu, Mašinski fakultet.. https://hdl.handle.net/21.15107/rcub_nardus_7005
Kostić O. Numerička simulacija strujnog polja vazduha u nadzvučnom mlazniku sa preprekom na izlazu. 2016;. https://hdl.handle.net/21.15107/rcub_nardus_7005 .
Kostić, Olivera, "Numerička simulacija strujnog polja vazduha u nadzvučnom mlazniku sa preprekom na izlazu" (2016), https://hdl.handle.net/21.15107/rcub_nardus_7005 .