lepkość i liczba Re

Transkrypt

lepkość i liczba Re
/HSNR üFLHF]\L/LF]ED5H\QROGVD
/HSNR ü MHVW PLDU WDUFLD ZHZQ WU]QHJR FLHF]\ WM RSRUX MDNL VWDZLDM GZLH OH FH
QLHVNR F]HQLHEOLVNRVLHELHZDUVWZ\FLHF]\SU]\SU]HVXZDQLXZ]JO GHPVLHELH/HSNR üMHVW
]DOH QDRGWHPSHUDWXU\FL QLHQLDLURG]DMXSá\QX
5R]Uy QLDVL OHSNR üG\QDPLF]Q LNLQHPDW\F]Q /HSNR üG\QDPLF]QDK3DV
/HSNR üNLQHPDW\F]QDQP V–VWRVXQHNOHSG\QDPGRJ VWR FLGDQHJRSá\QXZWHMVDPHM
WHPSHUDWXU]H
/HSNR FLROHMyZSRGDZDQHV MHV]F]HF] VWRZVWRNHVDFK6W6W FP V
υ=
η
ρ
3U]\QLHZLHONLFKSU GNR FLDFKVWUXPLHQLDUXFKMHVWODPLQDUQ\DSU]\SU]HNURF]HQLXSHZQHM
SU GNR FLJUDQLF]QHMSU]HFKRG]LZUXFKWXUEXOHQWQ\
0RPHQWSU]HM FLDRGUXFKXODPLQDUQHJRZWXUEXOHQWQ\]DOH \RGZDUXQNyZSU]HSá\ZXD
SU GNR üJUDQLF]QDE\ZDUy QD3U]HM FLHUXFKXODPLQDUQHJRZWXUEXOHQWQ\]DFKRG]L
QDWRPLDVWSU]\VWDáHMZDUWR FLJUDQLF]QHMEH]Z\PLDURZHJRSDUDPHWUXQD]\ZDQHJROLF]E 5H\QROGVD
/LF]ED5H\QROGVDMHVWWRVWRVXQHNVLáEH]ZáDGQR FLρZGGRVLáOHSNR FL 6WDQRZLRQD
NU\WHULXPGRZ\]QDF]DQLDFKDUDNWHU\VW\NLSU]HSá\ZX
Re
=
ZG
υ
*G]LH
•
•
•
GFKDUDNWHU\VW\F]Q\Z\PLDUOLQLRZ\QSGODSU]HSá\ZXSU]H]UXU E G]LHWRMHM
UHGQLFD
ZSU GNR üFKDUDNWHU\VW\F]QDSá\QX
QOHSNR üNLQHPDW\F]QD
υ=
K–OHSNR üG\QDPLF]QD
U–J VWR üSá\QX
Re =
η
ρ
ZG ρZG
=
η
η
ρ
ρLKV VWDáHGODRNUH ORQHJRPHGLXPQDWRPLDVWZLGZ]DOH QR FLRGZDUXQNyZ
PRJ E\ü GREUDQH Z Uy Q\ VSRVyE ,QDF]HM GOD NRU\W RWZDUW\FK OXE UXU D RGPLHQQLH GOD
]DJDGQLH GRW\F] F\FK Z]JO GQHJR UXFKX ]LDUQ L Sá\QX =DZV]H MHGQDN LVWRWD OLF]E\
5H\QROGVDMHVWWDNDVDPDLFKDUDNWHU\]XMHRQD]ZL ]HNPL G]\VLáDPLEH]ZáDGQR FLρZGD
VLáDPLOHSNR FLZVWUXPLHQLXSá\QXK
3U]\QLVNLFKZDUWR FLDFKOLF]E\5H\QROGVDZSU]HSá\ZLHGRPLQXM VLá\OHSNR FLGX D
ZDUWR üK3U]\Z\VRNLFKZDUWR FLDFKOLF]E\5H\QROGVD–VLá\EH]ZáDGQR FLSRUXV]DM FHJR
VL Sá\QXGX DZDUWR üLORF]\QXρZGDPDáDZDUWR üK
:DUWR üOLF]E\5H\QROGVD]DOH \RGWHPSHUDWXU\OHSNR üDWDN HRGFKDUDNWHUXGQD
L FLDQNRU\WDGQRL FLDQ\NRU\WDJáDGNLH5 Z\ V]DV]RUVWNLH5 QL V]D
'ODVWUXPLHQLZQDWXUDOQ\FKNRU\WDFKSU]HM FLHRGUXFKXODPLQDUQHJRZWXUEXOHQWQ\Z
]DOH QR FLRGZDUXQNyZWHPSHUDWXUDSU GNR üQDVW SXMHSU]\ZDUWR FLDFKOLF]E\
5H\QROGVDRGGR