A one dimensional isothermal mathematical modeling of cathode side of a Proton Exchange Membrane (PEM) fuel cell is developed for the water management problem. Water transport is investigated in both cathode Gas Diffusion Layer (GDL) and membrane through solving appropriate equations for fluid flow and mass transport in GDL and water transport within the membrane. The gaseous mixture flowing in...

Modern managements of water distribution system (WDS) need water quality models that are able to accurately predict the dynamics of water quality variations within the distribution system environment. Before water quality models can be applied to solve system problems, they should be calibrated. Although former researchers use GA solver to calibrate relative parameters, it is difficult to apply...

background: this study aimed to evaluated trends for iron and manganese concentrations in wells, reservoirs, and water distribution networks in qom city during the summer of 2012. methods: this was a cross-sectional study. the studied scopes consisted of groundwater (60 wells), reservoirs (10 tanks), and water distribution network (33 points). one sample was taken from each source monthly. stat...

Water scarcity is one of the main concerns of several countries around the world. In this context, several approaches have been proposed for resource conservation and available water augmentation through specific actions such as process intensification and the use, reclamation, reuse, and recycle of alternative water sources. Nonetheless, there are no reported methodologies optimizing the multi...

A longstanding problem in the study of sediment transport in gravel-bed rivers is related to the physical mechanisms governing bed resistance and particle motion. To study this problem, we investigated the motion of coarse spherical glass beads entrained by a steady shallow turbulent water flow down a steep two-dimensional channel with a mobile bed. This experimental facility is the simplest re...

abstract background: the pressure of consumption spots in eater supply systems is one of the most important hydraulic parameters can be used in optimized management of water distribution networks. since the pressure has some different effects on various parameters of the network management including its hydraulic functions, reliability, stability and leakage, its control is of great importance ...

Three macroscopic root water uptake models (Molz–Remson, Feddes, and Selim–Iskandar) have been widely used in modeling water flow in soil–plant systems. In this article, we use evapotranspiration data and soil water content data obtained from lysimeter measurements and root distribution data obtained in a nearby wheat field to evaluate the accuracy of these root water uptake models in predictin...

A novel route to the exponential trapping-time distribution within a solidlike state in water clusters is described. We propose a simple homogeneous network (SHN) model to investigate dynamics on the potential energy networks of water clusters. In this model, it is shown that the trapping-time distribution in a solidlike state follows the exponential distribution, whereas the trapping-time dist...