Investigation of Flow Field Around Submerged Bell Mouth Groin: An Experimental Study

Yıl 2011, Cilt: 3 Sayı: 1, 55 - 70, 01.03.2011

M.j. Uddin M.m. Hossain

Öz

A study was undertaken to investigate the flow field around bell mouth groin in a large mobile bed physical
model facility (46m x 11 m). A total number of 24 test runs were conducted. Three different discharges and four
different angles and two groin conditions (submerged and non-submerged) was considered. All tests were
conducted for 8 hours duration in clear water condition. Velocity data have been collected forming grids in both
vertical and horizontal direction around the vicinity of the bell mouth groin. Velocity was measured at 0.2, 0.4,
0.6 and 0.8 depths from the water surface by forming grids. Change in flow conditions around bell mouth groin
for various test run have been analyzed non-dimensionally in longitudinal, lateral and vertical direction. The
streamwise velocity along lateral direction was found that the lateral shifting of maximum velocity away from
the head of the bell mouth groin. In most cases, streamwise vertical velocity in lower part of the channel is found
higher than that of upper part. Streamwise vertical velocity profile has been found variable with different
discharges and does not follow its natural logarithmic pattern. Velocity vector indicates that flow is steady at
upstream along longitudinal direction. The flow diverted at head of structure and flows through sides of
structure towards downstream. A circulation of flow has been observed around head of structure after diverting
of flow towards down. Immediately after rear front of structure, relatively weak circulation of flow has been
observed. In this paper the results of test runs conducted under submerged conditions for 1500
and 900
angles
are reported.

Anahtar Kelimeler

Local scour, Submerged, Non-submerged, Bell mouth groin

Kaynakça

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