In order to model this Aeolian transport of sand, JenNins and Pasini ... flux and concentration within the transport layer are very thin and close to the bed.
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NUMERICAL SIMULATION OF AEOLIAN SALTATION WITHIN THE SEDIMENT TRANSPORT LAYER USING GRANULAR KINETIC THEORY JUAN PEDRO MARVAL LUGO1, LUIS ROJAS-SOLORZANO2 AND JENNIFER CURTIS3 8QLYHUVLGDG1DFLRQDO([SHULPHQWDO)UDQFLVFRGH0LUDQGD'HSDUWPHQWRI(QHUJHWLFMSPDUYDO#JPDLOFRP 2 8QLYHUVLGDG6LPRQ%ROLYDU'HSDUWPHQWRI&RQYHUVLRQRI(QHUJ\UURMDV#XVEYH 3 8QLYHUVLGDGGH)ORULGD'HSDUWPHQWRI&KHPLFDO(QJLQHHULQJMFXUWLV#FKHXÀHGX
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Recibido: marzo 2008
5HFLELGRHQIRUPD¿QDOUHYLVDGRRFWXEUH ABSTRACT
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SIMULACION NUMERICA DE LA SALTACION AEREA DENTRO DE LA CAPA DE TRANSPOPRTE DE SEDIMENTOS USANDO TEORIA CINETOCA GRANULAR RESUMEN /D PD\RUtD GH ORV ÀXMRV JUDQXODUHV TXH RFXUUHQ HQ FRQGLFLRQHV DPELHQWDOHV VRQ LQHVWDEOHV \ H[KLEHQ XQ FRPSOHMR FRPSRUWDPLHQWR ItVLFR /D IRUPDFLyQ \ PLJUDFLyQ GH GXQDV HQ ORV GHVLHUWRV VRQ FRQWURODGDV QR VyOR SRU HO ÀXMR GH SDUWtFXODVHQVDOWDFLyQVREUHHOOHFKRDUHQRVRVLQRWDPELpQSRUHOÀXMRWXUEXOHQWRGHDLUHDWPRVIpULFR(VWDVSDUWtFXODVHQ VDOWDFLyQDOFDQ]DQXQÀXMRPiVLFRGHVHGLPHQWDFLyQPi[LPROXHJRGHFLHUWRWLHPSROXHJRGHODPRYLOL]DFLyQLQLFLDOSRU GHVSOD]DPLHQWR\URGDPLHQWR$GLIHUHQFLDGHOWUDQVSRUWHGHVHGLPHQWRVHQDJXDHQHOFXDOODVSDUWtFXODVVRQHOHYDGDVSRU ODVXVSHQVLyQWXUEXOHQWDODVSDUWtFXODVHQVDOWDFLyQVRQDYLYDGDVHQODFDSDSULQFLSDOPHQWHSRUORVFKRTXHVH[LVWHQWHVGH SDUWtFXODSDUWtFXOD\SDUWtFXODOHFKRDUHQRVR3DUDHOPRGHODGRGHODWHRUtDGH7UDQVSRUWH(yOLFRGH$UHQD-HQNLQV\3DVLQL SURSXVLHURQXQPRGHORELIiVLFRXQHVWDGRHVWDEOH\XQLGLPHQVLRQDO XVDQGROD7HRUtD&LQpWLFD*UDQXODU7&* SDUDGHVFULELUORVHVIXHU]RVHQODIDVHVyOLGD(OSUHVHQWHWUDEDMRH[WLHQGHODLGHDRULJLQDOGH-HQNLQV\3DVLQLXVDQGRXQ PRGHORPiVUREXVWRGH7&*SDUDODVFRQWULEXFLRQHVFLQpWLFDVFROLVLRQDOHVDORVHVIXHU]RVWHQVRUHVGHODIDVHVyOLGDMXQWR a un modelo de fricción para los contactos continuos entre partículas. Fue seleccionada una geometría 2D rectangular con XQSHU¿OORJDUtWPLFRWtSLFRSDUDODYHORFLGDGGHHQWUDGDGHODLUH(VWHPRGHORHVYDOLGDGRFRQGDWRVH[SHULPHQWDOHVGH/LX \'RQJ \ORVUHVXOWDGRVGDGRVSRU3DQVLQL\-HQNLQV \0DUYDO 8QDEXHQDHVWLPDFLyQSDUDODHURVLyQ GHODVSDUWtFXODV\HOÀXMRPiVLFRGHVDOWDFLyQHVSUHGLFKD Palabras Clave6DOWDWLRQOD\HU*UDQXODUNLQHWLFWKHRU\&)' 80
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control devices for dunes motion or in the construction of KLJKZD\VRYHUSDVVHVWXQQHOV 7KH SUHVHQW ZRUN LQWURGXFHV D QXPHULFDO PRGHO IRU SUHGLFWLQJWKHÀRZRIVDQGSDUWLFOHVLQDVDOWDWLQJVWDWHRYHU a sand bed using an Eulerian model for both phases. The gas SKDVHWXUEXOHQFHFORVXUHPRGHOLVWKHVWDQGDUGNİPRGHO DQG WKH VROLGSKDVH VWUHVV LV GHVFULEHG XVLQJ *.7 ZLWK D IULFWLRQDO PRGHO ZKLFK LV DSSOLHG IRU VXVWDLQHG SDUWLFOH contacts. The mathematical model is implemented in the commercial code ANSYS-Fluent® and computed results DUHFRPSDUHGZLWKH[SHULPHQWDOGDWDJLYHQE\/LX 'RQJ DQGWKHPRGHOSUHGLFWLRQVJLYHQE\3DVLQL -HQNLQV DQG0DUYDOHWDO OVERVIEW OF SALTATION :KHQ VDQG SDUWLFOHV DUH GUDJJHG E\ D ORZ YHORFLW\ ZLQG WZR GLIIHUHQW PHFKDQLVPV RI WUDQVSRUW DUH UHODWHG WR WKH VXVSHQVLRQ 7KHVH WZR PHFKDQLVPV DUH NQRZQ DV ³6DOWDWLRQ´ DQG ³5HSWDWLRQ´ $QGUHRWWL HW DO UHFRJQL]HGE\%DJQROG PRUHWKDQ\HDUVDJRLQ KLVFODVVLFDOERRN³7KHSK\VLFVRIEORZQVDQGDQGGHVHUW GXQHV´6DOWDWLRQDQG5HSWDWLRQWRJHWKHUFRQWULEXWHWRWKH SDUWLFOH PDVV ÀX[ RYHU WKH VDQG\ VXUIDFH DQG FRQWURO WKH G\QDPLFVRIDGXQHJLYHQLWVSDUWLFXODUVKDSHFKDUDFWHULVWLFV LQWKHGHVHUW%DVHGRQSUHYLRXVUHVHDUFKLWLVNQRZQWKDW WKHSDUWLFOHVLQWHUDFWZLWKHDFKRWKHUDQGZLWKWKHVDQGEHG $QGUHRWWLHWDO )URPWKHHDUO\ZRUNRI%DJQROG¶V XQWLO QRZ PXFK UHVHDUFK HIIRUW ERWK H[SHULPHQWDO DQG WKHRUHWLFDOQXPHULFDOPRGHOLQJKDVEHHQGHYRWHGWRWU\LQJ WRGHVFULEHWKHFRPSOH[SKHQRPHQRORJ\RIVDOWDWLRQ 0DQ\ H[SHULPHQWDO ZRUNV KDV JLYHQ LQVLJKW LQWR GHWDLOV DERXWWKH6DOWDWLRQOD\HU/LX 'RQJ1DOSDQLVHW DO6SLHVHWDO%XWWHU¿HOG6WRXW ,YHUVHQ 5DVPXVVHQ5DVPXVVHQ 6RUHQVHQ 2NROL 1LVKLPXUD +XQW 1L HW DO 'RQJHWDO%DXHUHWDO 5HVHDUFK UHVXOWV DUH SUHVHQWHG LQ WHUPV RI WZR OHQJWK VFDOHV 7KH small length scale is on the order of the particle diameter and consists of measurements of the ejection and impact velocities, ejection and impact angles, trajectories of the GLIIHUHQWW\SHVRISDUWLFOHVVQRZPXVWDUGVHHGTXDUW] DQG SDUWLFOHVL]H7KHPHDQHMHFWLRQYHORFLW\LVSURSRUWLRQDOWR WKHIULFWLRQYHORFLW\X ZKLFKFKDUDFWHUL]HVWKHÀRZDQG KDVGLPHQVLRQVRIVSHHGEXWLVDPHDVXUHRIVKHDU(TQ DQGGRHVYHU\PXFKZLWKWKHJUDLQVL]H
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