in this paper, numerical investigation of a flat passive micromixer with heterogeneous surface properties that the flow through it, is driven by the electroosmotic flow have been presented. the governing equations, which consist of a laplace equation for the distribution of external electric potential, a poisson equation for the distribution of electric double layer potential, modified navier-s...

administrative regulations for water flow decrease distribution efficiency and effect the economical operation of irrigation networks. complications in distribution systems and the decrease in availability of water require study of the hydraulic performance of existing flow control structures. control systems designed by neyrpic (zayandeh rud network) and usbr (doroodzan network) were investiga...

statistical frequency analysis is the most common procedure for the analysis of flood data at a gauged location thatin first step it is needed to select a model to represent the population. among them, the central moment has been themost common and widely used, and with the using of computers, the application of the maximum likelihood hasincreased. this research was carried out in order to reco...

We use the multifractal formalism to describe the effects of dissipation on Lagrangian velocity statistics in turbulent flows. We analyze high Reynolds number experiments and direct numerical simulation data. We show that this approach reproduces the shape evolution of velocity increment probability density functions from Gaussian to stretched exponentials as the time lag decreases from integra...

regional analysis is one of the important methods for estimating the low flow in ungagged regions. investigation of the relations between effective factors of hydrological drought is the most important strategy to contrast and reduction of drought losses. in this study to analyze of low flow, the daily discharge data from 20 gauging stations with 25 years period (1988-2012) in the kashafroud ba...

existence of capacity drop phenomenon, as the difference between pre-queue and queue discharge flow rates, has been one of the controversial concepts of traffic engineering. several researches have focused on capacity drop existence and also its estimation issues. this paper aims to estimate capacity drop based not only on a comparison between breakdown and queue discharge flow rates, but also ...

Design of a natural dry cooling tower has been accomplished in two sections: the design of heat exchangers and the numerical solution of flow through the tower. Heat exchanger (Heller type) has been simulated thermodynamically and then coupled with a computer program, which calculated the turbulent natural convection flow through the tower. The computer program developed for this purpose can be...

An accurate description of the fluid flow and heat transfer within a Pressurized Water Reactor (PWR), for the safety analysis and reactor performance is always desirable. In this paper a mathematical model of the fundamental physical phenomena which are associated to a typical PWR is presented. The mathematical model governs the fluid dynamics in the reactor. Using commercial software CFX, a co...

Subcooled flow boiling in multi-microchannels can be used as an efficient thermal management approach in compact electrical devices. Highly subcooled flow boiling of HFE 7100 is studied in two microchannel heat sinks to choose a proper numerical model for simulating boiling flows in microchannels. Results of five different numerical models, including Volume of Fluid (VOF), Eulerian boiling, Eul...