Saeid Okhravi

Institute of Hydrology

This study investigated the influence of substrate level difference and material composition on dam break wave evolution over two erodible beds. Utilizing the Volume of Fluid (VOF) method, we tracked free surface advection and reproduced wave evolution using experimental data from the literature. For model validation, a comprehensive sensitivity an...

This study initially examines the various sources of flow resistance in sand-bed (lowland) and gravel-bed (mountainous) rivers along with the limitations of traditional estimation methods. The nondimensional hydraulic geometry approach, relating dimensionless flow discharge ( q * ) to the Darcy-Weisbach friction factor ( f ), has demonstrated good...

Rainwater harvesting (RWH), belonging to the broader family of detention-based Low Impact Development (LID) practices, is essential in mitigating water scarcity and addressing increased water demand due to climate change. By adopting this nature-based approach, runoff can be effectively managed, reducing its frequency, peaks, and volumes. This not...

A three-dimensional (3D) non-hydrostatic numerical model is established to investigate local scour around four aligned circular piles in uniform and non-uniform sediment mixtures and to provide information for improving scour countermeasures design. In the current study, unsteady Reynolds averaged Navier–Stokes (URANS) equations along with a Re-nor...

The Rozgrund water reservoir is one of the oldest reservoirs of the water supply system in the vicinity of Banská Štiavnica. In the past, it was one of the important reservoirs supplying the population with drinking water. Knowing the spatial and temporal variations of water temperature in the reservoir is the primary step to investigate and model...

The element of flow resistance is given distinctive attention due to its significant role in the assessment of the sediment entrainment processes, flood risk and management, and the effective design of water resources-related projects. Several flow resistance equations are well-acknowledged and they do not need to be calibrated when the uniform flo...

Groundwater potential maps constitute a valuable tool for groundwater sustainable management in arid regions. In this study, a groundwater potential map was developed for the Asadabad plain (Iran). The method deployed remote sensing techniques and hierarchical analysis, while geoelectric data were used to verify the results of the study. The method...

This study addressed a research concern that employing a fixed value for the bed roughness coefficient in lowland rivers (mostly sand-bed rivers) is deemed practically questionable in the presence of a mobile bed and time-dependent changes in vegetation patches. Accordingly, we set up 45 cross-sections in four lowland streams to investigate seasona...

This study presents the results of 32 laboratory experiments on local scour at a single pile and a 1 × 4 pile group for both uniform and non-uniform sediments under clear water conditions. The present study aims to evaluate the effects of different sediment beds made up of mixtures of sand and gravel (four-bed configurations) in d50 (1–3.5 mm) and...

The study addresses the research concern that the employment of fixed value for bed roughness coefficient in lowland rivers (mostly ‌sand-bed rivers) is deemed practically questionable in the presence of a mobile bed and time-dependent changes in vegetation patches. To address this issue, we set up 45 cross-sections in four lowland streams to inves...

Resistance to flow because of the presence of bed forms over armored river beds is of paramount ‎importance, leading to the effective design of water-resources-related projects. Based on the ‎findings over bed armored surfaces, it is shown that the controlling roughness (ks) can be taken ‎as equal to the median diameter of the armor layer. Analytic...

One of the main reasons for bridges failure at river crossings especially during floods is the riverbed scour at bridge pier foundation. Hence, the accurate prediction of maximum scour depth for saving financial resources and the safety of human lives is of paramount importance. However, most of the previous studies were based on local scour around...

The quantity of freshwater available per person in the world has been proceeded to decrease due to a combination of factors, including population increase, water pollution, inadequate planning and management of transboundary water, and inefficient operation of water supply and distribution systems. There is a direct water source to cease increasing...

Failure of bridges due to scour in the vicinity of piers poses a challenging problem to the hydraulic engineers. The main objectives of this study were to determine scour hole dimension, with its maximum scour depth as a function of time and at the equilibrium stage, the scour hole shapes and the investigation of the influence of sills on the scour...

Water conservation has had negative connotations for many people because it unintentionally implies hardship and inconvenience associated with rationing. However, water conservation is not simply a matter of using less water through restrictions. It is about careful management of water supply sources, use of water-saving technologies, reduction in...

This study was aimed at investigating the effects of flow distribution on a constructed subsurface horizontal flow wetland of 26 m length, 4 m width and one percent bed dip. Inlet configurations were selected as a variable parameter. Three different inlet flow configurations including midpoint–midpoint (A), corner–midpoint (B) and uniform–midpoint...

Lake Urmia in the northwest of Iran is the second largest hypersaline lake worldwide. During the past two decades, a significant water level decline has occurred in the lake. The Lake Urmia tragedy, which is perhaps the most disastrous water problem experienced by the Iranians to date, occurred not only as a result of frequent droughts and aggressi...

The study of flow and sediment size distribution in gravel bed Rivers has been the pivotal attention of many researchers for more than three decades. The surface grain size of gravel and cobble-bed rivers reflects the caliber and volume of sediment that is supplied to the channel and magnitude of discharge events that are capable of moving sediment...

He has published more than 200 publications, mainly in statistical and environmental hydrology and hydrometeorology. Saeid Okhravi received his degree in water engineering from IUT, Iran, and currently is a distinguished graduate student in water structure engineering in IUT. He has contributed in more than 10 scientific publications, mainly in sur...