Control of Sediment Entry into Intake Canals …
215
4 Conclusion
Intake canals divert water from main rivers for various purposes. Transport of sediment along with water causes reduction in the quality and quantity of water transported. Use of submerged vanes as river training structures at the entrance of intake
canals has been in existence since 1990. The present study introduces collars to
submerged vanes to reduce its local scour and prevent the collapse of vanes. An
optimum vane angle of 40° resulted in the lowest percentage of sediment entry into
the intake canal of 7.38%. On the contrary, maximum local scour for vanes with 40°
vane angle was found to be the highest with a value of 1.09 times the main channel
flow depth. Collars of diameters 3H v and 4H v were installed at the vane bottom to
reduce the local scour, where H v is the height of the vane. It is found that collar is
efficient in reducing local scour for all vane angles with a maximum reduction of
68.06% for 15° vane angle and 3H v collar diameter. Also, use of vanes with collars
at 15° vane angle resulted in a decrease of sediment entry into the intake canal by
24.84% and 5.24% for collar diameters 3H v and 4H v , respectively. However, the
collars reduced the performance of the optimum vane angle of 40° in terms of the
sediment entry percentage. It is concluded that collars are efficient in reduction of
sediment entry into intake canal for only lower vane angles. Perhaps the study of
collars could be extended for cases with lower vane spacing to vane height spacing
ratio, where the optimum vane angle is 15°.
References
1. Bosman DE, Prestedge GK, Rooseboom A, Slatter P T (2002) An investigation into the removal
of sediments from water intakes on rivers by means of jet type dredge pumps Water Research
Commission Report, 1187/1/02
2. Nakato T, Kennedy JF, Bauerly D (1990) Pump-station intakes hoaling control with submerged
vanes. J Hydraul Eng 116(1):119–128
3. Barkdoll BD, Ettema R, Odgaard AJ (1999) Sediment control at lateral diversions: limits and
enhancements to vane use. J Hydraul Eng 125(8):862–870
4. Odgaard AJ, Wang Y (1991) Sediment management with submerged vanes. I: theory. J Hydraul
Eng 117(3):267–283
5. Marelius F, Sinha SK (1998) Experimental investigation of flow past submerged vanes. J
Hydraul Eng 124(5):542–545
6. Yonesi HA, Omid MH, Haghiabi AH (2008) A study of the effects of the longitudinal
arrangement sediment behavior near intake structures. J Hydraul Res 46(6):814–819
7. Tan SK, Yu G, Lim SY, Ong MC (2005) Flow structure and sediment motion around submerged
vanes in open channel. ASCE J Waterw Port Coast Ocean Eng 131(3):132–136
8. Odgaard AJ, Kennedy JF (1983) River-bend bank protection by submerged vanes. J Hydraul
Eng 109(8):1161–1173
9. Odgaard AJ, Spoljaric A (1986) Sediment control by submerged vanes. J Hydraul Eng
112:1164–1180
10. Michell F, Ettema R, Muste M (2006) Case study: sediment control at water intake for large
thermal-power station on a small river. J Hydraul Eng 132(5):440–449
11. Ouyang HT, Lai JS, Yu H, Lu CH (2008) Interaction between submerged vanes for sediment
management. J Hydraul Res 46(5):620–627
215
4 Conclusion
Intake canals divert water from main rivers for various purposes. Transport of sediment along with water causes reduction in the quality and quantity of water transported. Use of submerged vanes as river training structures at the entrance of intake
canals has been in existence since 1990. The present study introduces collars to
submerged vanes to reduce its local scour and prevent the collapse of vanes. An
optimum vane angle of 40° resulted in the lowest percentage of sediment entry into
the intake canal of 7.38%. On the contrary, maximum local scour for vanes with 40°
vane angle was found to be the highest with a value of 1.09 times the main channel
flow depth. Collars of diameters 3H v and 4H v were installed at the vane bottom to
reduce the local scour, where H v is the height of the vane. It is found that collar is
efficient in reducing local scour for all vane angles with a maximum reduction of
68.06% for 15° vane angle and 3H v collar diameter. Also, use of vanes with collars
at 15° vane angle resulted in a decrease of sediment entry into the intake canal by
24.84% and 5.24% for collar diameters 3H v and 4H v , respectively. However, the
collars reduced the performance of the optimum vane angle of 40° in terms of the
sediment entry percentage. It is concluded that collars are efficient in reduction of
sediment entry into intake canal for only lower vane angles. Perhaps the study of
collars could be extended for cases with lower vane spacing to vane height spacing
ratio, where the optimum vane angle is 15°.
References
1. Bosman DE, Prestedge GK, Rooseboom A, Slatter P T (2002) An investigation into the removal
of sediments from water intakes on rivers by means of jet type dredge pumps Water Research
Commission Report, 1187/1/02
2. Nakato T, Kennedy JF, Bauerly D (1990) Pump-station intakes hoaling control with submerged
vanes. J Hydraul Eng 116(1):119–128
3. Barkdoll BD, Ettema R, Odgaard AJ (1999) Sediment control at lateral diversions: limits and
enhancements to vane use. J Hydraul Eng 125(8):862–870
4. Odgaard AJ, Wang Y (1991) Sediment management with submerged vanes. I: theory. J Hydraul
Eng 117(3):267–283
5. Marelius F, Sinha SK (1998) Experimental investigation of flow past submerged vanes. J
Hydraul Eng 124(5):542–545
6. Yonesi HA, Omid MH, Haghiabi AH (2008) A study of the effects of the longitudinal
arrangement sediment behavior near intake structures. J Hydraul Res 46(6):814–819
7. Tan SK, Yu G, Lim SY, Ong MC (2005) Flow structure and sediment motion around submerged
vanes in open channel. ASCE J Waterw Port Coast Ocean Eng 131(3):132–136
8. Odgaard AJ, Kennedy JF (1983) River-bend bank protection by submerged vanes. J Hydraul
Eng 109(8):1161–1173
9. Odgaard AJ, Spoljaric A (1986) Sediment control by submerged vanes. J Hydraul Eng
112:1164–1180
10. Michell F, Ettema R, Muste M (2006) Case study: sediment control at water intake for large
thermal-power station on a small river. J Hydraul Eng 132(5):440–449
11. Ouyang HT, Lai JS, Yu H, Lu CH (2008) Interaction between submerged vanes for sediment
management. J Hydraul Res 46(5):620–627