Tabanında gözenekli tabaka bulunan kanallardaki akışkan akışı ve konsantrasyon dağılımının sayısal olarak incelenmesi
Numerical analysis of fluid flow and concentration distribution of channels with porous layer on the base
Yazar: LEVENT DEMİRHAN
Danışman: PROF.DR. HAŞMET TÜRKOĞLU
Gazi Üniversitesi / Fen Bilimleri Enstitüsü / Makine Mühendisliği Ana Bilim Dalı
Derece: Yüksek Lisans, 2007
Konu: Makine Mühendisliği = Mechanical Engineering

Özet:
ivTABANINDA GÖZENEKL TABAKA BULUNAN KANALLARDAKAKI KAN AKI I VE KONSANTRASYON DA ILIMININ SAYISALOLARAK NCELENMES(Yüksek Lisans Tezi)Levent DEM RHANGAZ ÜN VERS TESFEN B L MLER ENST TÜSÜOcak 2007ÖZETBu çal/0mada taban/nda gözenekli tabaka bulunan iki paralel levhadanolu0an kanaldaki ak/0kan ak/0/ ve konsantrasyon da;/l/m/ say/sal olarakincelenmi0tir. Yap/ itibariyle PEM (Polimer Elektrolit Membranl/) yak/tpilinin katot k/sm/ndaki ak/0a benzer oldu;undan hem yak/t pili sistemihem de gözenekli yap/ hakk/nda bilgi verilmi0tir. Süreklilik, momentumve konsantrasyon denklemleri kontrol hacim metoduyla ayr/kla0t/r/larakve SIMPLE algoritmas/ kullan/larak geli0tirilen bir bilgisayar program/ile çözülmü0tür. Geli0tirilen program/ test etmek için, düz kanal ve altduvar/ gözenekli kanaldaki ak/0lar simule edilerek sonuçlar/, literatürsonuçlar/yla kar0/la0t/r/lm/0t/r. Gözeneklilik, Reynolds say/s/ vegözenekli tabaka kal/nl/;/n/n de;i0ik de;erleri için simülasyonlaryap/larak bu parametrelerin ak/0a ve konsantrasyon da;/l/m/na etkileriincelenmi0tir. Gözenekli tabakan/n gözeneklili;i artt/r/ld/;/ndaak/0kan/n gözenekli tabaka içindeki h/z/ artm/0 ve oksijenkonsantrasyonu azalm/0t/r. Reynolds say/s/n/n azalmas/, gözeneklitabakadaki boyutsuz h/z/n artmas/na ve konsantrasyonun azalmas/naneden olmu0tur.vGözenekli tabakan/n kal/nl/;/ artt/kça bu tabakadaki boyutsuz h/zgradyan/ ve gözenekli tabaka alt yüzeyindeki konsantrasyon azalm/0t/r.Ayr/ca gözeneklilik de;erinin artmas/yla, sürtünme katsay/s/n/n azald/;/belirlenmi0tir.Bilim Kodu : 914.1.002Anahtar Kelimeler : Gözenekli ortam, konsantrasyon da;/l/m/, say/salak/0kanlar dinami;iSayfa Adedi : 99Tez Yöneticisi : Prof. Dr. Ha0met TÜRKO LU

Abstract:
viNUMERICAL ANALYSIS OF FLUID FLOW AND CONCENTRATIONDISTRIBUTION OF CHANNELS WITH POROUS LAYER ON THE BASE(M.Sc.Thesis)Levent DEM RHANGAZI UNIVERSITYINSTITUTE OF SCIENCE AND TECHNOLOGYJanuary 2007ABSTRACTIn this study, fluid flow and concentration distribution in a parallel-platechannel with a porous layer on the base was numerically analyzed. As itis structurally similar to the flow in the cathode section of the PEM(Polymer Electrolyte Membrane) fuel cell, information has been givenboth on fuel cell system and the porous materials. Continuity,momentum and concentration equations were discritized by the controlvolume method and solved using a computer program developed usingSIMPLE algorithm. Flows in parallel-plate channel and in a channelwhose bottom wall is porous were solved by the software developed inthis study. Comparing the results of numerical simulations and theresult of analytical solution and results from literature, themathematical model and program developed were tested. Simulationswere made for different values of porosity, Reynolds number andthickness of porous layer. Using the results of these simulations, theeffects of these parameters on flow and concentration were analyzed. Itwas observed that when the porosity of porous layer is increased, thevelocity and concentration consumption in this layer also increases.Reducing Reynolds number resulted in increase of dimensionlessvelocity in this layer and decrease of concentration. As the thickness ofviithe porous layer increases, the dimensionless velocity gradient andconcentration decreased. Furthermore, when the porosity of porouslayer is increased, the fraction coefficient decreases.Science Code : 914.1.002Key Words : Porous medium, concentration distribution,computational fluid dynamicsPage Number : 99Adviser : Prof. Dr. Ha?met TÜRKOALU