Journals Information
Civil Engineering and Architecture Vol. 13(3), pp. 1875 - 1884
DOI: 10.13189/cea.2025.130331
Reprint (PDF) (1374Kb)
Hydraulic Evaluation of Morning Glory Spillways with Semi-Elliptical Notches
Ahmed. H. Mahmoud 1, Mamdouh Dardeer 1, Anani. E. Anani 1, Mahmoud Zayed 2,*
1 Department of Civil Engineering, Faculty of Engineering, Al-Azhar University, Egypt
2 Channel Maintenance Research Institute, National Water Research Center, Egypt
ABSTRACT
Morning glory spillways (MGSs) or shaft spillways have special design features allowing the excess water to be passed from the dam reservoir to the downstream outlet. In this research, holes within MGS featuring semi-elliptical notch shapes were experimentally investigated for discharge coefficient (
) and flow pattern compared with the classical MGS in case of without notches. This new and innovative design utilizing the semi-elliptical notches was examined for various approach Froude numbers (
) and notch numbers of 
= 2, 4 and 8 notches. The results indicated that the semi-elliptical notches had the ability to enhance the discharge coefficient and also breakdown the streamlines of flow vortex of simple shaft spillways. However, the semi-elliptical notches were more effective for lower , and consequently lower flow discharges. The impact of notches on the percentages of improvement in values decreased as rose compared with the classical MGS. A new discharge coefficient () formula for MGS with semi-elliptical notches was proposed which was valid for 
, 
, 
and 
.
KEYWORDS
Dam Reservoir, Discharge Coef铿乧ient, Morning Glory Spillway, Physical Modeling, Semi-Elliptical Notches, Vortex Breakers
Cite This Paper in IEEE or APA Citation Styles
(a). IEEE Format:
[1] Ahmed. H. Mahmoud , Mamdouh Dardeer , Anani. E. Anani , Mahmoud Zayed , "Hydraulic Evaluation of Morning Glory Spillways with Semi-Elliptical Notches," Civil Engineering and Architecture, Vol. 13, No. 3, pp. 1875 - 1884, 2025. DOI: 10.13189/cea.2025.130331.
(b). APA Format:
Ahmed. H. Mahmoud , Mamdouh Dardeer , Anani. E. Anani , Mahmoud Zayed (2025). Hydraulic Evaluation of Morning Glory Spillways with Semi-Elliptical Notches. Civil Engineering and Architecture, 13(3), 1875 - 1884. DOI: 10.13189/cea.2025.130331.