The goal of this work is to predict reasonable lifetime of a filter used to remove debris (e.g. foreign particles and gels) from the melt stream of an extrusion process. We are developing models which incorporate nonNewtonian porous media flow through a medium whose porosity changes as debris accumulates. Boundary conditions are based on the assumption of constant flow rate and coupling with ot...

Accurate measurement of peak velocity is critical to the assessment of patients with stenotic valvular disease. Conventional phase contrast (PC) methods for imaging high-velocity jets in aortic stenosis are susceptible to intravoxel dephasing signal loss, which can result in unreliable measurements. The most effective method for reducing intravoxel dephasing is to shorten the echo time (TE); ho...

Critical layers arise as a singularity of the linearized Euler equations when the phase speed of the disturbance is equal to the mean flow velocity. They are usually ignored when estimating the sound field, with their contribution assumed to be negligible. It is the aim of this paper to study fully both numerically and analytically a simple yet typical sheared ducted flow in order to distinguis...

recognizing of river flow pattern, deposition and erosion areas in meanders is highly important. despite the limitations of the physical models in laboratory investigation of flow pattern in meanders, mathematical models can be helpful. in this research, rsm and les turbulence models have been compared on sharp river bend of a laboratory flume using fluent software. the laboratory flume is a sh...

in the current study, five different atomistic water models (awms) are implemented, in order to investigate the impact of awms treatment on the water velocity profile and density number. for this purpose, molecular dynamics simulation (mds) of poiseuille flow in a nano-channel is conducted. considered awms are spc/e, tip3p, tip4p, tip4pfq and tip5p. to assessment of the ability of each model in...

In this study, the incipient motion of four groups sand, ranging from medium to very coarse particles, was experimentally examined using an acoustic Doppler velocimeter (ADV) in different water depths under hydraulically transitional flow condition. The transport criterion Kramer visual observation method used determine threshold conditions. Some equations for calculating average and near-bed v...

Flow separation at water intake is the main cause of head loss and flow discharge reduction. As a result, study of shape and size of separation is very essential when designing an optimum water intake. Water intake is normally built with a 90 degree angle to the main channel flow direction. However, the flow structure in this type of water intake consists of large separation size along with ...