https://irju.jdvu.ac.in/jspui/handle/123456789/239 2026-10-28T13:07:17Z 2026-10-28T13:07:17Z Mondal, Sudarshan https://irju.jdvu.ac.in/jspui/handle/123456789/10709 2026-10-28T11:33:02Z 2024-01-01T00:00:00Z

Title: New temporal scour depth formula for spur dike using statistical analysis of literature data and formulas Authors: Mondal, Sudarshan Abstract: Temporal scour depth (ds) estimation at spur dikes is a significant issue for application engineers and researchers because accurate prediction is required for real-time monitoring. Although several formulas were employed, a definitive study is still needed to determine which formula predicts most accurately. Therefore, this study aims to address this need by conducting a comparative analysis of dst prediction formulas at spur dikes under clear water conditions using laboratory datasets spanning the last 20 years. The analysis encompasses 14 parameters, each playing a significant role in scour depth prediction. These parameters include sediment coarseness, flow shallowness, porosity, densimetric Froude number, Reynolds number, spur dike length, height, thickness, orientation, width of flume, relative density, sediment uniformity, flow intensity and time. By considering these parameters, the study aims to identify the best option that will provide a more promising temporal scour depth formula based on a statistical analysis of data and formulas in literatures. Therefore, useful statistical influence factors are used to evaluate eight existing literature formulas alongside a newly derived formula concerning their effectiveness in predicting temporal scour depth. The model has been evaluated using different statistical performance indicators including Coefficient of Determination (R2), Root Mean Squared Error (RMSE), Nash Sutcliffe Efficiency (NSE), and Mean Bias Error (MBE). The weightage of each influencing factor on the accuracy of predictions is calculated using CRITIC, Entropy, and AHP methods. Ranking of each formula based on their performance is determined using PROMETHEE and TOPSIS. The findings of the study reveal that the newly proposed formula most accurately predicts the d, in terms of Pin as well as comparing statistical influence indicators such as R2=0.84, RMSE = 0.13, NSE = 0.86, and MBE-0.003. The ranking of the formulas indicates that the newly developed formula consistently achieves the top position for each combination of weightage, for both the corresponding rankings. The formula of Coleman et al. (2003) is found useful for predicting dau, particularly when equilibrium scour depth (dse) and equilibrium time (te) are known. Additionally, the formulas proposed by Nasrollahi et al. (2008) and Karimi et al. (2012a, b) are found with similar accuracy compared to Coleman et al. (2003). Overall, this study not only identifies the most reliable formula for predicting dar but also emphasizes the importance of considering practical constraints and real-world applicability in engineering solutions. By prioritizing practicality over idealistic approaches, engineers can make informed decisions that strike a balance between accuracy and feasibility.

2024-01-01T00:00:00Z Das, Animesh https://irju.jdvu.ac.in/jspui/handle/123456789/10708 2026-10-28T11:25:20Z 2024-01-01T00:00:00Z

Title: Simulation of flow around a circular pier on a scoured bed using CFD modelling software Authors: Das, Animesh Abstract: Bridges are an important part of a transportation network. Piers on which the superstructure of the bridge is provided are important components for the stability and safety of the bridge. There are many cases of failure of bridges due to scouring at their foundations. The scour around the piers is caused due to changes in flow patterns around piers due to the three-dimensional separation of the boundary layer, which has a large magnitude of turbulence and vortices around the piers. For designing pier foundations, it is very essential to estimate the correct depth of scour below river bed level since it affects the depth of the foundation and ultimately the cost of the bridge. The present study is directly relevant to understanding erosion mechanisms around a circular bridge pier model constructed in a river bend. In this research, a Unsteady Reynolds Averaged Navier-Stokes (URANS) approach is applied, to enable the simulation of scouring around the bridge pier model. This methodology allows an approach that numerically describes a complex three-dimensional (3D) scour behavior around bridge piers by coupling the changes in topography with the local detailed hydrodynamics. By using a commercial Computational Fluid Dynamics (CFD) tool, ANSYS in order to calculate scour. The dynamic mesh updating technique is implemented to move the bed and assures a practical and accurate scour simulation by individually updating the domain's riverbed at each time step. Simulation, in accordance with the experimental configuration of Dargahi (1989) for the turbulent channel flow past a circular cylinder, mounted in a flatbed, has been undertaken using the RANS approach. The projected results have been compared with those obtained from URANS models (i.e., k-e standard and k- SST (Shear Stress Transport), and with the experimental data, in order to verify the reliability and feasibility of the URANS. The coupling between RANS and the dynamic mesh technique has been undertaken to study the coherent structures around a circular bridge pier model in the initial stage of scour evolution. The approach produces a good prediction of the qualitative and quantitative characteristics observed by the experiment of Dargahi (1989). Furthermore, studying the transient behavior of the horseshoe vortex system upstream of the circular pier model, during the scour process evolution shows that the main vortex has the bimodal oscillation phenomenon, which increases the ability of these vortices to remove the sediment around the circular pier model.

2024-01-01T00:00:00Z Sahanur Jamal Mondal https://irju.jdvu.ac.in/jspui/handle/123456789/10707 2026-10-28T11:10:31Z 2024-01-01T00:00:00Z

Title: Assesment of sustainable water sources for water distribution system using watergems: a case study of udaynarayanpur zone-i & zone-ii, howrah district, west bengal Authors: Sahanur Jamal Mondal Abstract: This research study addresses critical gaps in the optimization of rural water distribution systems, particularly in rapidly expanding regions like India, with a focus on adhering to CPHEEO norms and Jal Jeevan Mission guidelines. The objective is to develop a comprehensive model for gravity flow pipeline distribution networks using WaterGEMS software, analyzing factors such as velocity, flow, headloss, pressure, hydraulic grade, and pressure head at various nodes. The study emphasizes understanding trade-offs in pipe sizing, pressure, velocity, and head losses to enhance system efficiency and cost- effectiveness. Long-term performance and sustainability, including beyond intermittent water supply scenarios, are also investigated. Additionally, the study explores the integration of emerging technologies like artificial intelligence and optimization algorithms to improve network design with energy efficiency. The research identifies deficiencies in network analysis and design, particularly in addressing leakages and pressure differences. Comparisons between simulated and actual networks reveal the software's viability for accurate analysis and design improvements. The study further underscores the software's ability to handle various network problems with simplicity and accuracy and also analysis the tubewell yields under Udaynarayanpur Block. The Udaynarayanpur Zone I&II Piped Water Supply Scheme in West Bengal serves as a case study, demonstrating the practical application of WaterGEMS software for a network consisting of 984 pipes and 984 junctions. This research contributes to filling the research gap in optimizing rural water distribution systems, offering valuable insights for developing robust, economically viable, and compliant water supply systems, applicable to regions facing similar challenges.

2024-01-01T00:00:00Z Satpati, Aritra https://irju.jdvu.ac.in/jspui/handle/123456789/10706 2026-10-28T11:04:58Z 2024-01-01T00:00:00Z

Title: Development of a hydraulic model for stormwater drainage network using sewergems software: a case study of kamarhati municipality Authors: Satpati, Aritra Abstract: Rapid urbanization has led to significant challenges in managing storm water runoff from developed areas. If left unaddressed, this can result in urban flooding and degradation of water quality in rivers and receiving waters. Effective urban drainage systems are crucial to mitigate these impacts and ensure sustainable urban development. This study assesses the storm water drainage system in Kamarhati (Ward numbers 10-15), Kolkata, using statistical analysis, GIS, Google Earth Software, and SewerGEMS software. The research identifies construction, management, and design problems as the main challenges facing the existing drainage system. SewerGEMS software is used to analyze the system, and mitigation measures are proposed to address these problems. The study recommends periodic cleaning and modification of slope to avoid construction alignment problems. "SewerGEMS” software, developed by Bentley Systems, USA, was extensively used in this study to analyze and propose mitigation measures for the drainage system in Kamarhati region. The software's dynamic, multi-platform capabilities enabled efficient and cost-effective project completion. Input data was entered into the software, and results were interpreted to identify drainage system shortcomings. Probable solutions were proposed to address these issues, including periodic cleaning and modification of slope to avoid construction alignment problems. The study demonstrates the effectiveness of “SewerGEMS” in developing sustainable drainage systems, highlighting its potential for future applications.

2024-01-01T00:00:00Z