TY  - JOUR
AU  - Ristić, Slavica
AU  - Polić, Suzana
AU  - Radojković, Bojana
AU  - Linić, Suzana
AU  - Bikić, Vesna
AU  - Jegdić, Bore
AU  - Pavlović, Miloš
PY  - 2018
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/2743
AB  - U radu su prikazani rezultati laserskog čišćenja korozivnih i drugih naslaga na metalnom arheološkom predmetu koji je nađen u Dunavu. Korišćen je Nd:YAG laser, energije do 750mJ i talasne dužine λ=1064nm i 532nm. Efikasnost čišćenja je ispitivana u funkciji energije lasera, talasne dužine, broja impulsa, odnosno vremena eksponiranja i vlažnosti površine uzorka. Rezultati skidanja nepoželjnih slojeva sa površine uzorka, kao i morfoloških promena na osnovnom materijalu, ispitivani su optičkom i skenirajućom elektronskom mikroskopijom ( OM i SEM), a ispitivanje mikrohemijskih promena izvršeno je pomoću energijske disperzione spektrometrijske analize (EDX) i rendgensko fluorescentnom spektroskopijom (XRF). Pokazano je da za čišćenje ovog uzorka veću efikasnost ima λ= 532nm i da je uticaj vlažnosti površine na efikasnost laserskog čišćenja veoma mali. Istraživanja obavljena na arheološkom uzorku iz Dunava, pokazuju da je primena lasera u čišćenju nepoželjnih slojeva veoma efikasna, bezbedna i ekološki prihvatljiva.
AB  - The paper presents the results of laser cleaning of corrosive and other deposits on a metal archaeological artefact from the Danube. Nd: YAG laser, energy up to 750 mJ and wavelengths λ = 1064 nm and 532 nm is used. The cleaning efficiency was examined in the function of laser energy, wavelength, and number of pulses, i.e. the time of exposure and moist of the surface of the sample. The results of removal of unwanted layers from the surface of the artefact and morphological changes on the base material were examined by optical and scanning electronic microscopy (OM and SEM). Micro-chemical changes have been determined by energy dispersive X-ray analysis (EDX) and x-ray fluorescence spectrometry (XRF). It has been shown that λ = 532 nm has higher efficiency for cleaning this sample and that the surface moisture has very small influence on laser cleaning efficiency. Research carried out on the archaeological object from the Danube shows that the application of lasers in the cleaning of undesirable layers is very efficient, safe and environmentally friendly.
PB  - Inženjersko društvo za koroziju, Beograd
T2  - Zaštita materijala
T1  - Istraživanje mogućnosti primene lasera u čišćenju arheoloških metalnih predmeta
T1  - Laser cleaning of the archaeological metal sample from the Danube
EP  - 421
IS  - 3
SP  - 410
VL  - 59
DO  - 10.5937/zasmat1803410R
ER  - 

@article{
author = "Ristić, Slavica and Polić, Suzana and Radojković, Bojana and Linić, Suzana and Bikić, Vesna and Jegdić, Bore and Pavlović, Miloš",
year = "2018",
abstract = "U radu su prikazani rezultati laserskog čišćenja korozivnih i drugih naslaga na metalnom arheološkom predmetu koji je nađen u Dunavu. Korišćen je Nd:YAG laser, energije do 750mJ i talasne dužine λ=1064nm i 532nm. Efikasnost čišćenja je ispitivana u funkciji energije lasera, talasne dužine, broja impulsa, odnosno vremena eksponiranja i vlažnosti površine uzorka. Rezultati skidanja nepoželjnih slojeva sa površine uzorka, kao i morfoloških promena na osnovnom materijalu, ispitivani su optičkom i skenirajućom elektronskom mikroskopijom ( OM i SEM), a ispitivanje mikrohemijskih promena izvršeno je pomoću energijske disperzione spektrometrijske analize (EDX) i rendgensko fluorescentnom spektroskopijom (XRF). Pokazano je da za čišćenje ovog uzorka veću efikasnost ima λ= 532nm i da je uticaj vlažnosti površine na efikasnost laserskog čišćenja veoma mali. Istraživanja obavljena na arheološkom uzorku iz Dunava, pokazuju da je primena lasera u čišćenju nepoželjnih slojeva veoma efikasna, bezbedna i ekološki prihvatljiva., The paper presents the results of laser cleaning of corrosive and other deposits on a metal archaeological artefact from the Danube. Nd: YAG laser, energy up to 750 mJ and wavelengths λ = 1064 nm and 532 nm is used. The cleaning efficiency was examined in the function of laser energy, wavelength, and number of pulses, i.e. the time of exposure and moist of the surface of the sample. The results of removal of unwanted layers from the surface of the artefact and morphological changes on the base material were examined by optical and scanning electronic microscopy (OM and SEM). Micro-chemical changes have been determined by energy dispersive X-ray analysis (EDX) and x-ray fluorescence spectrometry (XRF). It has been shown that λ = 532 nm has higher efficiency for cleaning this sample and that the surface moisture has very small influence on laser cleaning efficiency. Research carried out on the archaeological object from the Danube shows that the application of lasers in the cleaning of undesirable layers is very efficient, safe and environmentally friendly.",
publisher = "Inženjersko društvo za koroziju, Beograd",
journal = "Zaštita materijala",
title = "Istraživanje mogućnosti primene lasera u čišćenju arheoloških metalnih predmeta, Laser cleaning of the archaeological metal sample from the Danube",
pages = "421-410",
number = "3",
volume = "59",
doi = "10.5937/zasmat1803410R"
}

Ristić, S., Polić, S., Radojković, B., Linić, S., Bikić, V., Jegdić, B.,& Pavlović, M.. (2018). Istraživanje mogućnosti primene lasera u čišćenju arheoloških metalnih predmeta. in Zaštita materijala
Inženjersko društvo za koroziju, Beograd., 59(3), 410-421.
https://doi.org/10.5937/zasmat1803410R

Ristić S, Polić S, Radojković B, Linić S, Bikić V, Jegdić B, Pavlović M. Istraživanje mogućnosti primene lasera u čišćenju arheoloških metalnih predmeta. in Zaštita materijala. 2018;59(3):410-421.
doi:10.5937/zasmat1803410R .

Ristić, Slavica, Polić, Suzana, Radojković, Bojana, Linić, Suzana, Bikić, Vesna, Jegdić, Bore, Pavlović, Miloš, "Istraživanje mogućnosti primene lasera u čišćenju arheoloških metalnih predmeta" in Zaštita materijala, 59, no. 3 (2018):410-421,
https://doi.org/10.5937/zasmat1803410R . .

TY  - JOUR
AU  - Milićev, Snežana
AU  - Pavlović, Miloš D.
AU  - Ristić, Slavica
AU  - Vitić, Aleksandar
PY  - 2002
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/319
AB  - Da bi se eliminsala pojava jakog udarnog talasa pri nadzvučnom opstrujavanju projektila, koja zanačajno povećava otpor pri letu krozvazduh, na njegov vrh montira se igla. U radu se daju rezultati eksperimentalnog istraživanja uticaja oblika igle na aerodinamičke koeficijente (uzgona, otpora, momenta propinjanja, kao i položaj centra pritiska) pri nadzvučnom opstrujavanju tela zaobljenog vrha. Eksperiment je izveden u aereotunelu, za jednu vrednost Mahovog i Rejnoldsovog broja, kao i za jednu vrednost napadnog ugla α = 2o. Za telo bez igle, kao i za telo sa četiri različita modela igle merene su aerodinamičke sile i momenti. U radu su predloženi kriterijumi za procenu uticaja igle zasnovani isključivo na rezultataima dobijrenim vizualizacijom strujanja. Igla najboljih karakteristika, od ispitanih konfiguracija, izabrana na osnovu izmerenih aerodinamičkih koeficijenata, uklapa se u ove kvalitativne kriterijume.
AB  - In order to eliminate the appearance of a strong shock wave at a supersonic flight of a missile, which considerably increases the drag during its flight through the air, a spike is mounted on its nose. Presented paper offers the results of an experimental analysis of the influence of the spike's shape on the aerodynamic coefficients (drag, lift and pitching moment coefficient, as well as the location of the center of pressure) at supersonic flow past blunt-nosed body. The experiment was carried out in a wind tunnel, for one value of Mach and Reynolds numbers, and for one value of the angles of attack, α = 2o. For the body without spike, and with four different spike shapes, the aerodynamic forces and moment were measured. Using only the photos obtained by Schlieren visualization of the flow, the paper proposes a criterion of estimating the aerodynamic effect of the spike shape. The best spike shape from the experimental set of spikes, selected by the measurement of the aerodynamic coefficients, coincided with this qualitative criterion.
PB  - Univerzitet u Nišu, Niš
T2  - Facta universitatis - series: Mechanics, Automatic Control and Robotics
T1  - O uticaju igle na nadzvučno strujanje oko zaobljenog tela
T1  - On the influence of spike shape at supersonic flow past blunt bodies
EP  - 382
IS  - 12
SP  - 371
VL  - 3
UR  - https://hdl.handle.net/21.15107/rcub_machinery_319
ER  - 

@article{
author = "Milićev, Snežana and Pavlović, Miloš D. and Ristić, Slavica and Vitić, Aleksandar",
year = "2002",
abstract = "Da bi se eliminsala pojava jakog udarnog talasa pri nadzvučnom opstrujavanju projektila, koja zanačajno povećava otpor pri letu krozvazduh, na njegov vrh montira se igla. U radu se daju rezultati eksperimentalnog istraživanja uticaja oblika igle na aerodinamičke koeficijente (uzgona, otpora, momenta propinjanja, kao i položaj centra pritiska) pri nadzvučnom opstrujavanju tela zaobljenog vrha. Eksperiment je izveden u aereotunelu, za jednu vrednost Mahovog i Rejnoldsovog broja, kao i za jednu vrednost napadnog ugla α = 2o. Za telo bez igle, kao i za telo sa četiri različita modela igle merene su aerodinamičke sile i momenti. U radu su predloženi kriterijumi za procenu uticaja igle zasnovani isključivo na rezultataima dobijrenim vizualizacijom strujanja. Igla najboljih karakteristika, od ispitanih konfiguracija, izabrana na osnovu izmerenih aerodinamičkih koeficijenata, uklapa se u ove kvalitativne kriterijume., In order to eliminate the appearance of a strong shock wave at a supersonic flight of a missile, which considerably increases the drag during its flight through the air, a spike is mounted on its nose. Presented paper offers the results of an experimental analysis of the influence of the spike's shape on the aerodynamic coefficients (drag, lift and pitching moment coefficient, as well as the location of the center of pressure) at supersonic flow past blunt-nosed body. The experiment was carried out in a wind tunnel, for one value of Mach and Reynolds numbers, and for one value of the angles of attack, α = 2o. For the body without spike, and with four different spike shapes, the aerodynamic forces and moment were measured. Using only the photos obtained by Schlieren visualization of the flow, the paper proposes a criterion of estimating the aerodynamic effect of the spike shape. The best spike shape from the experimental set of spikes, selected by the measurement of the aerodynamic coefficients, coincided with this qualitative criterion.",
publisher = "Univerzitet u Nišu, Niš",
journal = "Facta universitatis - series: Mechanics, Automatic Control and Robotics",
title = "O uticaju igle na nadzvučno strujanje oko zaobljenog tela, On the influence of spike shape at supersonic flow past blunt bodies",
pages = "382-371",
number = "12",
volume = "3",
url = "https://hdl.handle.net/21.15107/rcub_machinery_319"
}

Milićev, S., Pavlović, M. D., Ristić, S.,& Vitić, A.. (2002). O uticaju igle na nadzvučno strujanje oko zaobljenog tela. in Facta universitatis - series: Mechanics, Automatic Control and Robotics
Univerzitet u Nišu, Niš., 3(12), 371-382.
https://hdl.handle.net/21.15107/rcub_machinery_319

Milićev S, Pavlović MD, Ristić S, Vitić A. O uticaju igle na nadzvučno strujanje oko zaobljenog tela. in Facta universitatis - series: Mechanics, Automatic Control and Robotics. 2002;3(12):371-382.
https://hdl.handle.net/21.15107/rcub_machinery_319 .

Milićev, Snežana, Pavlović, Miloš D., Ristić, Slavica, Vitić, Aleksandar, "O uticaju igle na nadzvučno strujanje oko zaobljenog tela" in Facta universitatis - series: Mechanics, Automatic Control and Robotics, 3, no. 12 (2002):371-382,
https://hdl.handle.net/21.15107/rcub_machinery_319 .