in the present study a quasi 2-d numerical model is developed for calculating air concentration distribution in rapid flows. the model solves air continuity equation (convection diffusion equation) in the whole flow domain. this solution is then coupled with calculations of the free surface in which air content in the flow is also considered. to verify the model, its results are compared with a...

Liquid water transport and removal from the gas diffusion layer GDL and gas channel of a polymer electrolyte fuel cell PEFC are studied experimentally and theoretically. In situ observations of the liquid water distribution on the GDL surface and inside the gas channel were made in an operating transparent PEFC. Liquid droplet formation and emergence from the GDL surface are characterized and t...

In this paper conjugated heat transfer in thermal entrance region through the sinusoidal wavy channel has been investigated. The fluid flow is assumed to be laminar, steady state, incompressible, and hydrodynamically fully developed. A constant heat flux is assumed to be applied on the outer edge of the channel wall. In this study the governing equations including continuity, momentum and energ...

because of its kinetic nature and computational advantages, the lattice boltzmann method (lbm) has been well accepted as a useful tool to simulate micro-scale flows. the slip boundary model plays a crucial role in the accuracy of solutions for micro-channel flow simulations. the most used slip boundary condition is the maxwell slip model. the results of maxwell slip model are affected by the ac...

Sasanian’s imperial policy aimed to construct new towns, massive irrigation infrastructures, and land modification bydepopulating rural areas in order to carry out massive agriculture projects particularly in Khuzestan. Shushtar with itsancient relics presents a unique chance to investigate some of these development activities, mainly in terms of irrigation.Several chief irrigation organs have ...

ion channels are naturally occurring pores through the proteins that regulate the passage of ions and thus maintain the concentration of ions inside and outside the cell. the ion channels control many physiological functions and they can show selectivity for a specific ion. ion channels are mostly observed in nerve cells and muscle cells. the influx of ions into cells can be regulated by a gate...

Ion channels are naturally occurring pores through the proteins that regulate the passage of ions and thus maintain the concentration of ions inside and outside the cell. The ion channels control many physiological functions and they can show selectivity for a specific ion. Ion channels are mostly observed in nerve cells and muscle cells. The influx of ions into cells can be regulated by a gate...

abstract study of turbidity current hydrodynamics plays an important role in increasing the economical life of dams though reduction in sediment accumulation. in the present experimental study, the effect of entrance densimetric froude number of turbidity current in sub and super critical conditions (fr =0.6-3.5) have been tested through effect of channel slope and change related to opening hei...

The efficiency and economical performance of sewer systems is an essential issue in urban drainage. The need for sewers to carry sediment has been recognized for many years. One of the main problems in designing sewerage systems is the sediment deposition. Sedimentation in sewers occurs regularly according to the alternating natural flow. The present study investigates the hydraulic characteris...