Studies have been made on the temperature dependence of both the hydraulic conductivity, L(p), and the THO diffusion coefficient, omega, for a series of cellulose acetate membranes (CA) of varying porosity. A similar study was also made of a much less polar cellulose triacetate membrane (CTA). The apparent activation energies, E(a), for diffusion across CA membranes vary with porosity, being 7....

An increase in the flow velocity in flowthrough large porous media and deflection of flow regime from Darcy law causes a nonlinear relationship between hydraulic gradient and pore velocity of media. So many investigations have done previously in such Medias. One of the most important subjects in flowthrough large porous media is relationship between friction coefficient and flow characteristics...

A numerical model of a water distribution network designed for a town with 50,000 inhabitants was implemented in EPANET. The paper presents a methodology for computing the chlorine residual concentration decay in the above urban size water distribution system, over a 3 days period of time. The hydraulic system fits a gravity distribution scheme, consisting of a looped network with a tank, 42 no...

The available studies for estimating the characteristics of hydraulic jump are only for artificial or natural beds, and very limited researches have simultaneously considered artificial and natural beds. The aim of this study is to present comprehensive equations and models for predicting the characteristics of hydraulic jump in artificial and natural rough beds with various dimensions, arrange...

Study patterns of flow in pipes with rough walls can be considered relevant, as the use of rough surfaces is a method of heat transfer. In the theoretical study of heat transfer processes in heat exchangers and devices used in various fields of technology, it is very important to know the basic laws of flow in rough pipes in turbulent regime. Flow patterns for rough pipes differs from the behav...

Vegetative filter strips (VFS) are an environmental management tool used to reduce sediment and pesticide transport from surface runoff. Numerical models of VFS such as the Vegetative Filter Strip Modeling System (VFSMOD-W) are capable of predicting runoff, sediment, and pesticide reduction and can be useful tools to understand the effectiveness of VFS and environmental conditions under which t...

The aim of this paper was to verify the common methods of hydraulic conductivity estimation for soil assessment in respect to wastewater disposal. The studies were conducted on three types of sandy soils. Hydraulic conductivity was determined using a scale effect-free laboratory method, empirical equations and compared with measurements estimated from a laboratory infiltration column with ident...

In cold climate regions winter conditions significantly influence the performance of stormwater infiltration devices. Frozen soil and water storage by snow changes their operation. In this paper winter operation of a grassed infiltration swale was investigated using on-site and laboratory measurements. The field investigation of a grassed swale at a parking place in an Alpine region showed that...

The interstitial fluid pressure of the submucosa of the gastric fundus was monitored by means of Guyton's capsules in dogs anesthetized with pentobarbital. The intracapsular pressure (ICP) was measured during secretion produced by: a) hypertonic solutions placed inside the stomach; b) arterial hypertension (200 mmHg) applied during intra-arterial infusion of histamine, and c) intra-arterial inf...

This study presents an artificial neural network (ANN) model to predict the values of the longitudinal dispersion coefficient ) ( l D in rivers from their main hydraulic parameters. The model can be considered as a useful aid to water quality monitoring in rivers. The ANN model is a relatively new promising technique which can make use of the river width, depth, velocity, and shear velocity for...