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Contribution to the modeling of the spatial distribution of radiation inside the furnace of the pulverized coal fired boiler.

dc.contributor.advisorTucaković, Dragan R.
dc.contributor.otherŽivanović, Titoslav
dc.contributor.otherBelošević, Srđan
dc.creatorCrnomarković, Nenad Đ.
dc.date.accessioned2018-03-05T13:19:39Z
dc.date.available2016-01-05T12:01:35Z
dc.date.available2018-03-05T13:19:39Z
dc.date.issued2012-09-21
dc.identifier.urihttp://eteze.bg.ac.rs/application/showtheses?thesesId=376
dc.identifier.urihttps://fedorabg.bg.ac.rs/fedora/get/o:6035/bdef:Content/download
dc.identifier.urihttp://vbs.rs/scripts/cobiss?command=DISPLAY&base=70036&RID=513958307
dc.identifier.urihttp://nardus.mpn.gov.rs/123456789/2283
dc.identifier.urihttp://vinar.vin.bg.ac.rs/handle/123456789/7246
dc.description.abstractzračenjem za ložište za sagorevanje ugljenog praha. Primena modela prikazana je naprimeru ložišta energetskog bloka snage 210 MW. Zapremina ložišta je podeljena na7956 zapreminskih zona, a zidovi ložišta na 2712 površinskih zona. Za svaki par zonaizračunate su direktne i totalne površine razmene, za medijum koji apsorbuje, emituje iizotropno rasipa zračenje. Razmena energije zračenjem određena je na grubojnumeričkoj mreži koju su sačinjavale zapreminske zone. Ostale fizičke veličineodređene su na finoj numeričkoj mreži, koja je dobijena podelom svake zapreminskezone na određeni broj kontrolnih zapremina. Formirane su tri fine numeričke mreže dabi se pokazalo da su rezultati nezavisni od numeričke mreže. Usvojena fina numeričkamreža sastojala se od 573 440 kontrolnih zapremina. Matematički model je verifikovankroz poređenje rezultata sa rezultatima merenja temperatura i upadnih flukseva zračenjana levom zidu ložišta. Matematičkim modelom je pokazano da gasna faza plamena uložištu formira centralni vrtlog, kojim su zahvaćene i čestice ugljenog praha.Visokotemperatursko jezgro plamena se formira u središtu ložišta. Maksimalna vrednostapsorbovanih flukseva zračenja po zidovima ložišta dobijena je u neposrednoj blizinigorionika, što je u skladu sa poznatom raspodelom flukseva zračenja za ložišta satangencijalnim rasporedom gorionika. Matematički model je primenjen za određivanjerazmene energije zračenjem u uslovima smanjenog opterećenja kotla. Pokazano je da sasmanjenjem produkcije pare kotla opadaju temperatura na kraju ložišta i vrednostiapsorbovanih flukseva zračenja na zidovima ložišta. Formiran je i istovetan matematičkimodel koji sadrži model zračenja šest flukseva. Poređenjem rezultata numeričkihsimulacija, dobijeno je zadovoljavajuće slaganje dva matematička modela ložišta.Formirani matematički model može se koristiti za analizu procesa u ložištu, kao i zaispitivanje procesa razmene energije zračenjem u ložištu.sr
dc.description.abstractA mathematical model that contained Hottel’s zonal model of radiative heat exchangewas formed for the pulverized coal fired furnace. Application of the mathematicalmodel was shown on the example of a furnace that was a part of 210 MW thermal unit.The furnace volume was divided into 7956 volume zones, whereas furnace walls weredivided into 2712 surface zones. For each pair of zones, direct exchange areas and totalexchange areas were calculated. Radiative heat exchange was determined using thecoarse numerical grid that was composed of volume zones. All other physical variableswere determined using the fine numerical grid that was formed by division of eachvolume zone to a certain number of control volumes. Three fine numerical grids wereformed to show that results were grid independent. Adopted fine numerical gridcomprised 573 440 control volumes. Mathematical model was verified through thecomparison with results of the temperature and incident wall radiative fluxesmeasurements. It was shown by mathematical modeling that gas phase formed centralvortex, which influenced the motion of the pulverized coal particles. The hightemperaturecore of the flame was formed in the center of the furnace. Maximal valuesof the absorbed wall radiative heat fluxes were obtained in the vicinity of the burners, inaccordance with the known distribution of the wall radiative fluxes for the tangentiallyfired furnace. Mathematical model was applied for the calculation of the radiative heatexchange in the conditions of reduced boiler loads. It was shown that temperature at thefurnace outlet and the absorbed wall radiative fluxes decreased with the decreased boilerload. Mathematical model that contained six-flux model of radiation was also formed.Comparison of the results of numerical simulations showed acceptable level ofagreement between mathematical models. Investigation showed that mathematicalmodel, which contained Hottel’s zonal model of radiative heat exchange, could be usedfor the analysis of the process inside the furnace and for investigation of the radiativeheat exchange, as well.en
dc.formatapplication/pdf
dc.languagesr
dc.publisherУниверзитет у Београду, Машински факултетsr
dc.rightsopenAccessen
dc.sourceУниверзитет у Београдуsr
dc.subjectHottel-ov zonalni model, toplotno zračenje, razmena energije zračenjem,ložište, ugljeni prah, matematički model, temperatursko polje, radijaciono polje,fluksevi zračenja na zidu, opterećenje kotlasr
dc.subjectHottel’s zonal model, thermal radiation, radiative heat exchange, furnace,pulverized coal, mathematical model, temperature field, radiative field, wall radiativeheat fluxes, boiler loaden
dc.titlePrilog modeliranju prostorne distribucije zračenja u ložištu kotla za sagorevanje ugljenog prahasr
dc.titleContribution to the modeling of the spatial distribution of radiation inside the furnace of the pulverized coal fired boiler.en
dc.typedoctoralThesisen
dc.rights.licenseBY-NC
dcterms.abstractТуцаковић, Драган; Живановић, Титослав; Белошевић, Срђан; Црномарковић, Ненад Ђ.; Прилог моделирању просторне дистрибуције зрачења у ложишту котла за сагоревање угљеног праха; Прилог моделирању просторне дистрибуције зрачења у ложишту котла за сагоревање угљеног праха;
dc.identifier.fulltexthttp://vinar.vin.bg.ac.rs//bitstream/id/1440/Disertacija.pdf


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