SeyedMohsen Sajjadi
@scu.ac.ir
Assistant Professor, Department of Water Science and Engineering
Shahid Chamran University of Ahvaz
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
Saeed Hajialigol, Javad Ahadiyan, Seyed Mohsen Sajjadi, Mohammad Azamathulla Hazi, Aaron Anil Chadee, Hossein Azizi Nadian, and James T. Kirby
Elsevier BV
Mohammadreza Haghdoost, Esmail Lakzian, Reza Norouzi, John Abraham, SeyedMohsen Sajjadi, and Javad Ahadiyan
Springer Science and Business Media LLC
Ashkan Pilbala, Mahmood Shafai Bejestan, Seyed Mohsen Sajjadi, and Luigi Fraccarollo
Springer Science and Business Media LLC
AbstractThe effect of the elliptic ratio on the hydraulic performance of the LOPAC gate has been investigated using experimental and Computational Fluid Dynamics $$CFD$$ CFD simulations (Flow-$$3D$$ 3 D Hydro). Experiments and simulations were carried out at three different flow discharges, three different submerged ratios, and five different elliptic ratios. In this context, the $$CFD$$ CFD model was first calibrated and verified using the measured data, and then $$CFD$$ CFD simulation was performed. The ratio of upstream/downstream flow depth, the flow discharge coefficient, and the energy dissipation through the gate have been calculated and analyzed, and the three-dimensional features of the flow have been described. Based on the results, the elliptical LOPAC gates with circular weirs determine extreme values of the controlled flow parameters. Asymmetric recirculation downstream of the gate is sometimes observed in the model predictions. The use of Coriolis coefficients relevant to the entire cross-section, here deployed just for the circular and the traditional rectangular Lopac gates, has allowed a concise way to report and compare complex flows for any experimental condition.
Seyed Mohsen Sajjadi, Mohsen Kazemi, Seyed Amin Asghari Pari, and Seyed Mahmood Kashefipour
Springer Science and Business Media LLC
Mohammadreza Haghdoost, SeyedMohsen Sajjadi, Manoochehr Fathi Moghadam, and Javad Ahadiyan
IWA Publishing
Abstract The present experimental study analyzes the effects of lateral jet flow (LJF) in a stilling basin with abruptly expanding channels on the stabilization and the significant characteristics of spatial hydraulic jump. The experiments were carried out with three different inflow Froude numbers (8.77, 9.56, and 10.87), three different distances of the LJF from the abruptly expanding channel (0 m, 0.25 m, and 0.5 m), and one and two LJF (i.e., the number of active orifices in the LJF system). According to the results, the distances of the LJF from the narrow channel and the number of LJF improve the hydraulic jump's stabilization and flow pattern enhancement in the tailwater channel. Additionally, the average sequent depth and the spatial jump length decreased by 14% and 20%, respectively, compared to no LJF. Also, using LJF increases relative energy dissipation by 12.45% on average.
Shokoofeh Sharoonizadeh, Javad Ahadiyan, Anna Rita Scorzini, Mario Di Bacco, Mohsen Sajjadi, and Manoochehr Fathi Moghadam
Springer Science and Business Media LLC
Mehrdad Moradi, Mohsen Sajjadi, Ram Balachandar, Ali Arman, and Adrian Ilinca
Informa UK Limited
Hooman Kheybar, Seyed Mohsen Sajjadi, and Javad Ahadyan
Wiley
Saeed Hajialigol, Javad Ahadiyan, Mohsen Sajjadi, Anna Rita Scorzini, Mario Di Bacco, and Mahmood Shafai Bejestan
American Society of Civil Engineers (ASCE)
Shokoofeh Sharoonizadeh, Javad Ahadiyan, Anna Rita Scorzini, Mario Di Bacco, Mohsen Sajjadi, and Manoochehr Fathi Moghadam
MDPI AG
This study presents an investigation on the use of submerged counterflow jets as a means for stabilizing the spatial hydraulic jump occurring in abruptly expanding channels. The characteristics of the flow downstream from the stilling basin and the main parameters influencing the effectiveness of the device in improving flow uniformity and reducing scouring potential are examined in laboratory tests, under several geometric configurations and hydraulic boundary conditions. The position within the stilling basin and the jet density (i.e., the number of orifices issuing the counterflow jets) were found to be important parameters influencing the performance of the device. Overall, the results indicate that this dissipation system has promising capabilities in forcing the transition from supercritical to subcritical flow, by significantly shortening the protection length needed to limit the phenomena of instability associated with spatial hydraulic jumps.
Ashkan Pilbala, SeyedMohsen Sajjadi, and Mahmood Shafai Bejestan
Elsevier BV
Abstract This study intended to investigate the hydraulic performance of the new types of LOPAC gates, namely the elliptical LOPAC (EL) gate, and the rectangular LOPAC (RL) gate for irrigation canals. To that end, 90 experiments were carried out at three different flow discharges (25, 35, and 45 l/s), three different submergence ratios (y2/y1 = 0.7, 0.8, and 0.9) and five different gate opening angles (35, 40, 45, 50, and 52.5°). In the EL gate, as the submergence ratio decreased by 20%, the maximum increase in Cd for the discharges of 25, 35, 45 l/s at 52.5° of gate opening angles happened in the order of 0.426, 0.475, and 0.506, respectively. Moreover, the maximum decrease ratios in ΔE/E1 followed by 20% increase in the submergence ratio for the same discharges at 35° of gate opening angles were 0.195, 0.1944, and 0.1922 respectively. Finally, the empirical rating curve and equations were proposed to predict Cd and ΔE/E1 for both the EL and RL gate models. For the EL gate, the RMSE ratios for the proposed Cd and ΔE/E1 equations were obtained 0.0027 and 0.0021 respectively.
ARNAU BAYON, MEHRDAD MORADI, MOHSEN SAJJADI, and FRANCISCO JOSE VALLES-MORAN
The International Association for Hydro-Environment Engineering and Research (IAHR)
One of the most difficult issues to address when designing hydraulic structures is the energy dissipation in spillways, outlets and stilling basins. Different approaches exist to ensure that the flow properties downstream of the hydraulic structure are suitable to avoid foundation scour, streambed erosion and other undesirable processes. The present work focuses on the numerical modeling of Multi-Horizontal Submerged Jets (MHSJ) stilling basins. This particular type of structure aims at forming a submerged hydraulic jump where the staggered distribution of inlet jets interferes with the formation of coherent turbulent structures, thus affecting vortex shedding and so contributing to more favorable sequent depth ratios and overall energy dissipation. The work presented herein aims at characterizing and understanding of the flow in MHJS stilling basins. To this end, an air-water RANS k-ε model based on the VOF method is implemented using the CFD code OpenFOAM. A three-dimensional structured mesh of rectangular elements with selective refinement is used. The model accuracy is assessed using experimental data obtained from a physical model free from scale effects. This process shows that CFD models are capable of reproducing the flow in MHSJ stilling basins. The existent limitations when reproducing flow features such as vortex formation and hydraulic jump roller characteristics are discussed and some recommendations for future work are outlined.