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Cyu stattyu treba vikifikuvati dlya vidpovidnosti standartam yakosti Vikipediyi Bud laska dopomozhit dodavannyam dorechnih vnutrishnih posilan abo vdoskonalennyam rozmitki statti serpen 2023 Turbulentna difuziya ce perenesennya masi tepla chi impulsu v mezhah sistemi cherez vipadkovi i haotichni ruhi yaki zalezhat vid chasu Zmist 1 Zagalnij opis 2 Zastosuvannya 2 1 Atmosferna difuziya i zabrudnennya 2 2 Turbulentni polum ya difuziyi 3 Modelyuvannya 3 1 Pidhid Ejlera 3 2 Pidhid Lagranzha 3 3 Rishennya 4 Majbutni doslidzhennya 5 Literatura 6 PosilannyaZagalnij opis RedaguvatiTurbulentna difuziya vidbuvayetsya koli turbulentni ridinni sistemi dosyagayut kritichnoyi umovi u vidpovid na zsuvnij potik yakij vinikaye v rezultati poyednannya nadmirnih koncentraciyi gradiyentiv shilnosti gradiyentiv i visokih shvidkostej Ce vidbuvayetsya nabagato shvidshe nizh v molekulyarnij difuziyi i tomu nadzvichajno vazhlivo dlya problem sho stosuyutsya peremishuvannya i transportuvannya v sistemah pov yazanih z gorinnyam zabrudnyuyuchih rechovin rozchinenogo kisnyu i rozchiniv v promislovosti U cih oblastyah turbulentna difuziya diye yak vidminnij sposib shvidkogo znizhennya koncentraciyi vidu v ridini abo seredovishi v tih vipadkah koli ce neobhidno dlya shvidkogo zmishuvannya pid chas obrobki abo shvidkogo zabrudnennya rechovini abo zmenshennya zabrudnennya dlya bezpeki Prote bulo nadzvichajno vazhko rozrobiti konkretnu i povnistyu funkcionalnu model yaka mozhe buti zastosovana do difuziyi cogo vidu u vsih turbulentnih sistemah cherez nemozhlivist oharakterizuvati mittyevu i peredbachenu shvidkist ridini odnochasno Turbulentnij potik ye rezultatom kilkoh takih harakteristik yak neperedbachuvanist shvidkist difuziyi visoti rivnya kolivannya zavihrenosti i disipaciyi kinetichnoyi energiyi Zastosuvannya RedaguvatiAtmosferna difuziya i zabrudnennya Redaguvati Atmosferna dispersiya abo difuziya vivchaye yak zabrudnyuvachi zmishuyutsya v navkolishnomu seredovishi Ye bagato faktoriv vklyuchenih v comu procesi modelyuvannya napriklad v yakih sharah atmosferi vidbuvayetsya zmishuvannya stabilnist navkolishnogo seredovisha i yakij tip u rechovini sho zabrudnyuye ta u dzherela Modeli Ejlera i Lagranzha buli vikoristani dlya modelyuvannya atmosfernoyi difuziyi i mayut vazhlive znachennya dlya pravilnogo rozuminnya togo yak zabrudnyuvachi reaguyut i zmishuyutsya v riznih seredovishah Obidvi ci modeli vrahovuyut yak vertikalni tak i gorizontalni vitri j dodatkovo vikoristovuyut teoriyu difuziyi Fika dlya obliku turbulentnosti Vrahovuyuchi te sho ci metodi povinni vikoristovuvati idealni umovi i robiti chislenni pripushennya v konkretnij moment chasu to vazhko rozrahuvati vpliv turbulentnoyi difuziyi na zabrudnyuvachi z visokoyu tochnistyu Teoriya difuziyi Fika i podalshi dosyagnennya v galuzi doslidzhen z atmosfernoyi difuziyi mozhut buti zastosovani dlya modelyuvannya vplivu kotrij zdijsnyuyetsya potochnim rivnem vikidiv zabrudnyuvachiv z riznih dzherel na atmosferu Turbulentni polum ya difuziyi Redaguvati Vikoristovuyuchi plosku lazerno indukovanu fluorescenciyu i zobrazhennya procesiv chastinok velosimetriyi sposterigayetsya trivale doslidzhennya vplivu turbulentnoyi difuziyi na polum ya Osnovni galuzi doslidzhennya vklyuchayut v sebe sistemu zgoryannya v gazovih palnikah vikoristovuvanih dlya viroblennya elektroenergiyi i himichnih reakcij v strumeni polum ya difuziyi za uchastyu metanu vodnyu i azotu Krim togo dvoh impulsne zobrazhennya temperaturi Releya vikoristovuyetsya dlya korelyaciyi ekstenkciyi i zapalyuvannya dilyanok zi zminoyu temperaturi i zmishuvannyam himichnih rechovin v polum yi Modelyuvannya RedaguvatiPidhid Ejlera Redaguvati Pidhid Ejlera do turbulentnoyi difuziyi fokusuyetsya na neskinchenno malomu obsyazi v pevnomu prostori i chasi v neruhomij sistemi vidliku pri yakij viznachayutsya fizichni vlastivosti taki yak masa impuls i temperatura Model korisna oskilki statistika Ejlera poslidovno vimirna i proponuye velike zastosuvannya v himichnih reakciyah Analogichno molekulyarni modeli vona povinna zadovolnyati ti zh principi sho i rivnyannya neperervnosti nizhche de advekciyu elementa abo vidu vrivnovazhuyut jogo difuziyi generaciyi za dopomogoyu reakciyi a takozh dodatkovo ci diyi z inshih dzherel abo tochok a takozh rivnyan Nav ye Stoksa c i t x j u j c i D i 2 c i x j x j R i c 1 c N T S i x t displaystyle begin aligned partial c i over partial t partial over partial x j u j c i D i partial 2 c i over partial x j partial x j R i c 1 c N T S i x t end aligned nbsp i 1 2 N displaystyle begin aligned i 1 2 N end aligned nbsp Tam de c i displaystyle c i nbsp koncentraciya vidiv interesu u j displaystyle u j nbsp shvidkist t displaystyle t nbsp chas x j displaystyle x j nbsp napryamok D i displaystyle D i nbsp konstanta difuziyi molekul R i displaystyle R i nbsp shvidkist c i displaystyle c i nbsp generuvannya reakciyi S i displaystyle S i nbsp norma c i displaystyle c i nbsp sho generuyetsya dzherelom Zvernit uvagu sho c i displaystyle c i nbsp ce koncentraciya na odinicyu ob yemu a ne spivvidnoshennya zmishuvannya kg kg u fonovij ridini Yaksho rozglyadati inertni vidi vidsutnist reakciyi bez dzherel i vvazhati molekulyarnu difuziyu neznachnoyu advekciya dodankiv v livij chastini rivnyannya zalishitsya Virishennya ciyeyi modeli zdayetsya trivialnim spochatku prote mi ne vrahovuvali vipadkovu skladovu shvidkosti plyus serednyu shvidkist v u j u u j displaystyle u j bar u u j nbsp sho yak pravilo asociyuyetsya z turbulentnoyu povedinkoyu U svoyu chergu koncentraciya rozchinu dlya modeli Ejlera povinna takozh mati vipadkovu skladovu c j c c j displaystyle c j bar c c j nbsp Ce prizvodit do problemi zamikannya neskinchennih zminnih i rivnyan ta unemozhlivlyuye virishennya dlya pevnoyi c i displaystyle c i nbsp na zaznachenih pripushennyah Na shastya isnuye nablizhene zakrittya u vprovadzhenni koncepciyi turbulentnoyi difuziyi i jogo statistichnih nablizhen dlya vipadkovih komponentiv koncentraciyi i shvidkosti vid turbulentnogo peremishuvannya u j c K j j c x j displaystyle langle u j c rangle K jj partial c over partial x j nbsp De K j j displaystyle K jj nbsp ye turbulentnoyu difuziyeyu Pidstavlyayuchi v pershe rivnyannya bez perervnosti ta ignoruvannya reakcij dzherela i rezultati molekulyarnoyi difuziyi v nastupnomu diferencialnomu rivnyanni z urahuvannyam tilki turbulentnogo difuzijnogo nablizhennya v turbulentnij difuziyi c i t u j c x j x j K j j c x j displaystyle partial c i over partial t bar u j partial c over partial x j partial over partial x j Bigl K jj partial c over partial x j Bigl nbsp Na vidminu vid molekulyarnoyi difuziyi D yaka ye postijna to turbulentna difuziya ye virazom matrici yaka mozhe zminyuvatisya v prostori i takim chinom ne mozhe buti prijnyata za mezhami zovnishnoyi pohidnoyi Pidhid Lagranzha Redaguvati Model Lagranzha turbulentnoyi difuziyi vikoristovuye ruhomu sistemu vidliku shob sliduvati trayektoriyi i peremishennya cogo vidu yak voni ruhayutsya za statistikoyu kozhnoyi chastki okremo Spochatku chastka znahoditsya v misci roztashuvannya x x 1 x 2 x 3 displaystyle x x 1 x 2 x 3 nbsp v moment chasu t displaystyle t nbsp Ruh chastinki opisuyetsya yiyi jmovirnistyu isnuyuchih v pevnomu elementi obsyagu v chas t displaystyle t nbsp sho opisuyetsyaPS x 1 x 2 x 3 t d x 1 d x 2 d x 3 PS x t d x displaystyle Psi x 1 x 2 x 3 t dx 1 dx 2 dx 3 Psi x t dx nbsp yakij sliduye za funkcyami shilnosti jmovirnosti takij sho PS x t Q x t x t PS x t d x displaystyle Psi x t int infty infty int infty infty int infty infty Q x t x t Psi x t dx nbsp Tam de funkciya Q displaystyle Q nbsp ye jmovirnistyu shilnosti dlya perehodu chastinok Koncentraciyu chastinok v misci roztashuvannya x displaystyle x nbsp i chas t displaystyle t nbsp to mozhna obchisliti shlyahom pidsumovuvannya jmovirnostej chisla chastinok yaki sposterigayutsya v takij sposib c x t i 1 m PS i x t displaystyle langle c x t rangle sum i 1 m Psi i x t nbsp Yakij potim obchislyuyutsya shlyahom povernennya do integraliv c x t Q x t x 0 t 0 c x 0 t 0 d x 0 t 0 t Q x t x t S x t d t d x displaystyle langle c x t rangle int infty infty int infty infty int infty infty Q x t x 0 t 0 langle c x 0 t 0 rangle dx 0 int infty infty int infty infty int infty infty int t 0 t Q x t x t S x t dtdx nbsp Takim chinom cej pidhid vikoristovuyetsya dlya ocinki stanu i shvidkosti chastinok shodo svoyih susidiv i navkolishnogo seredovisha i nablizhayetsya vipadkovi koncentraciyi i shvidkosti pov yazani z turbulentnoyu difuziyeyu v statistici yih ruhu Rishennya Redaguvati Otrimanij rozchin dlya virishennya kincevih rivnyan pererahovanih vishe dlya oboh modelej dlya analizu statistichnih danih v turbulentnomu potoci yak rezultat duzhe shozhi virazhennya dlya obchislennya serednoyi koncentraciyi v konkretnij tochci z bezperervnogo dzherela Obidva rishennya rozrobleni Gaussian Plume i praktichno identichni v pripushenni sho vidhilennya v ploshini u napryamkah x y z displaystyle x y z nbsp pov yazani z turbulentnoyu difuziyeyu c x y z q 2 p s y s z exp y 2 s y 2 z 2 s z 2 displaystyle langle c x y z rangle q over 2 pi sigma y sigma z exp Biggl Biggl y 2 over sigma y 2 z 2 over sigma z 2 Biggl Biggl nbsp Des y 2 2 K y y x u s z 2 2 K z z x u displaystyle sigma y 2 2K yy x over bar u sigma z 2 2K zz x over bar u nbsp q displaystyle q nbsp shvidkist emisiyi u displaystyle u nbsp shvidkist vitru s i 2 displaystyle sigma i 2 nbsp vidhilennya vid napryamku i displaystyle i nbsp Pri riznih zovnishnih umovah takih yak napravlena shvidkist potoku viter i umovi navkolishnogo seredovisha dispersiya i koeficiyenti turbulentnoyi difuziyi vimiryuyutsya i vikoristovuyutsya dlya rozrahunku garnoyi ocinki koncentraciyi v konkretnij tochci vid dzherela Cya model duzhe korisna v atmosfernih naukah osoblivo pri roboti z koncentraciyami zabrudnyuyuchih rechovin v zabrudnenni povitrya yaki vihodyat z takih dzherel yak miscya zgoryannya richki abo avtomobili na dorozi Majbutni doslidzhennya RedaguvatiOskilki zastosuvannya matematichnih rivnyan turbulentnih potokiv i difuziyi nastilki vazhki doslidzhen v cij oblasti ne vistachalo do nedavnogo chasu U minulomu laboratorni zusillya vikoristovuvali dani zi stacionarnogo potoku v potokah abo z ridin yaki mayut velike chislo Rejnoldsa sho protikayut cherez trubu ale otrimati tochni dani z cih metodiv vazhko Ce vidbuvayetsya tomu sho ci metodi vklyuchayut idealnij potik yakij ne mozhe imituvati umovi turbulentnogo potoku neobhidni dlya rozrobki modelej turbulentnoyi difuziyi Z rozvitkom komp yuternogo modelyuvannya ta programuvannya vcheni zmogli zmodelyuvati turbulentnij potik dlya togo shob krashe zrozumiti turbulentnu difuziyu v atmosferi i v ridinah V danij chas na naukovo doslidnij roboti vikoristovuyetsya dva osnovni dodatki Persha ploska lazerno indukovana fluorescenciya yaka vikoristovuyetsya dlya viyavlennya mittyevoyi koncentraciyi zi shvidkistyu do odnogo miljona tochok v sekundu Cya tehnologiya mozhe buti pov yazana z velosimetriyeyu zobrazhennya chastinok yake viyavlyaye mittyevi dani po shvidkosti Na dodatok do viyavlennya koncentraciyi i shvidkosti danih ci metodi mozhut buti vikoristani dlya vivedennya prostorovoyi korelyaciyi i zmini v navkolishnomu seredovishi Oskilki tehnologiyi i komp yuterni zdatnosti shvidko rostut ci metodi takozh znachno polipshilis i jmovirno ci metodi budut v centri podalshih doslidzhen z modelyuvannya turbulentnoyi difuziyi Krim cih dosyagnen takozh buli uspihi i v polovih robotah vikoristovuvani do togo yak komp yuteri stali dostupni Monitoring v realnomu chasi turbulentnosti shvidkosti i strumu dlya zmishuvannya ridini teper mozhlivij Ce doslidzhennya dovelo vazhlivist dlya vivchennya zmishuvannya cikliv zabrudnyuyuchih rechovin v turbulentnih potokah osoblivo dlya pitnoyi vodi Yak doslidzhuyut metodi i pidvishennya dostupnosti bagato novih oblastej viyavlyayut interes do vikoristannya cih metodiv Vivchennya yak robototehnika abo komp yuteri mozhut viyaviti zapah i zabrudnyuyuchi rechovini v turbulentnomu potoci ye odniyeyu z oblastej yaki jmovirno viyavlyayut velikij interes v naukovih doslidzhennyah Ci doslidzhennya mogli b dopomogti prosunuti ostanni doslidzhennya napriklad rozmishennya datchikiv v aviacijnih kabinah dlya efektivnogo viyavlennya biologichnoyi zbroyi chi virusiv Literatura Redaguvati Hideto Yoshida Masuda Hiroaki Higashitani Kō 2006 Powder Technology Handbook 3rd ed Boca Raton CRC ISBN 1 57444 782 3 OCLC 64679080 Roberts P J W amp Webster D R 2002 Turbulent Diffusion In Shen Hayley H Environmental fluid mechanics theories and applications New York American Society of Civil Engineers ISBN 0 7844 0629 4 OCLC 50090138 Beychok M R 2005 Fundamentals Of Stack Gas Dispersion 4th ed ISBN 0 9644588 0 2 Walcek C J 2002 Effects of wind shear on pollution dispersion Atmospheric Environment 36 3 511 7 doi 10 1016 S1352 2310 01 00383 1 Su L K Sun O S amp Mungal M G 2006 Experimental investigation of stabilization mechanisms in turbulent lifted jet diffusion flames Combustion and Flame 144 3 494 512 doi 10 1016 j combustflame 2005 08 010 Hult J Meier U Meier W Harvey A amp Kaminski C F 2005 Experimental analysis of local flame extinction in a turbulent jet diffusion flame by high repetition 2 D laser techniques and multi scalar measurements Proceedings of the Combustion Institute 30 1 701 9 doi 10 1016 j proci 2004 08 069 Csanady G T 1973 Turbulent diffusion in the environment Geophysics and astrophysics monographs 3 Boston MA D Reidel Publishing Company ISBN 90 277 0260 8 OCLC 629866 Pandis Spyros N Seinfeld John H 2006 Atmospheric chemistry and physics from air pollution to climate change J Wiley ISBN 0 471 72017 8 OCLC 62493628 JAMS Glossary Initials 2010 March 1 Closure problem Arima T Matsuura Y amp Oharu S 2007 Computation of air flows and motion of environmental pollutants over complex geographical topographies Journal of Computational and Applied Mathematics 204 1 187 196 doi 10 1016 j cam 2006 04 036 horizontal tab character in title at position 40 help Bilger R W 1989 Turbulent diffusion flames Annu Rev Fluid Mech 21 101 135 doi 10 1146 annurev fl 21 010189 000533 Posilannya Redaguvatihttps web archive org web 20100528081515 https share sandia gov crf article php id 144 Turbulent Diffusion Flame Research http www shodor org master environmental air plume index html Gaussian Plume Model Calculator http courses washington edu cewa567 Plumes PDF Turbulent Diffusion and Gaussian Plume Model from University of Washington http www lnu edu ua wp content uploads 2016 05 dis vovk pdf nedostupne posilannya z listopadaa 2019 http visnyk ami lnu edu ua db 251 800 28 pdf Otrimano z https uk wikipedia org w index php title Turbulentna difuziya amp oldid 40199180