Next Article in Journal
Water Protection Zoning as an Instrument of Preservation for Lake Baikal
Previous Article in Journal
Gender and Community Mainstreaming in Fog Water Collection Systems
Article

Characteristics of Positive Surges in a Rectangular Channel

by 1,2, 1,3,*, 1,3, 1,3 and 1,3
1
Nanjing Hydraulic Research Institute, Nanjing 210029, Jiangsu, China
2
College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing 210098, Jiangsu, China
3
State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Nanjing 210029, Jiangsu, China
*
Author to whom correspondence should be addressed.
Water 2018, 10(10), 1473; https://doi.org/10.3390/w10101473
Received: 17 September 2018 / Revised: 9 October 2018 / Accepted: 16 October 2018 / Published: 19 October 2018
(This article belongs to the Section Hydraulics and Hydrodynamics)
A positive surge is an unsteady open channel flow motion characterized by an increase of flow depth. In previous experimental studies, a positive surge was typically induced by either a sudden increase of discharge in a channel or by the rapid closure of a downstream sluice gate, thus leading to a steep initial profile. However, in many instances, the evolution of a positive surge is of a progressive manner (e.g., in the downstream navigation canal during the emptying operation of lock chambers). In the present work, the inception and development of a positive surge induced by a progressive increase of discharge was investigated in a rectangular channel with a smooth bed. Both undular and breaking surges were studied. The results demonstrate that the maximum wave height at the first wave crest of an undular surge is in very close agreement with the McCowan theory. Additionally, the wave amplitude essentially shows a linearly increasing trend with an increasing surge Froude number up to Fr0 = 1.26 to 1.28, whereas it tends to suggest a power law reduction for larger surge Froude numbers. Moreover, the dispersion of undular surges is consistent with the linear wave theory only for surge Froude numbers close to unity. Overall, the present study demonstrates the unique features of positive surges induced by a progressive increase of discharge. View Full-Text
Keywords: undular surge; breaking surge; progressive; dispersion characteristics; surge Froude number undular surge; breaking surge; progressive; dispersion characteristics; surge Froude number
Show Figures

Figure 1

MDPI and ACS Style

Zheng, F.; Li, Y.; Xuan, G.; Li, Z.; Zhu, L. Characteristics of Positive Surges in a Rectangular Channel. Water 2018, 10, 1473. https://doi.org/10.3390/w10101473

AMA Style

Zheng F, Li Y, Xuan G, Li Z, Zhu L. Characteristics of Positive Surges in a Rectangular Channel. Water. 2018; 10(10):1473. https://doi.org/10.3390/w10101473

Chicago/Turabian Style

Zheng, Feidong, Yun Li, Guoxiang Xuan, Zhonghua Li, and Long Zhu. 2018. "Characteristics of Positive Surges in a Rectangular Channel" Water 10, no. 10: 1473. https://doi.org/10.3390/w10101473

Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop