abstract drastic precipitations in unmorally times always are one of the important factors that created abundant damages in different geographical areas. in this research, three precipitations that occurred in summer 2009 in mashhad were investigated. the investigation of variation graphs of meteorological parameters show significant decreasing of air pressure and temperature and increasing of ...

Advection has been the standard transport mechanism in flow visualization. Diffusion, in contrast, has not been considered important in visual flow field analysis so far, although it is inherent to many physical processes. We present a novel technique that allows for interactive 3D visualization of both advection and diffusion in unsteady fluid flow. We extend texture-based flow visualization, ...

Abstract. We demonstrate here that a single physical phenomenon, specifically, naturally changing balance between intensities of temperature advection and diffusion in the viscous ice media, may influence entire spectrum Pleistocene variability from orbital to millennial timescales.

water quality prediction is a valuable tool for pollutant control in aquatic environments. a river system is selected and one-dimensional flow is assumed for the simulation of pollutant transport in this paper. advective and diffusive terms of transport equation are considered separately. different functions of advective transport are proposed and applied for a specified velocity on the discret...

prediction of spatial and temporal variation of water quality is vital for managing pollutantsdisposal into the rivers. depletion of dissolved oxygen (do) takes place due to the consumption of oxygen bymicrobes to digest bio-degradable pollutants which enter a water course. reaeration takes place in a specificrate depending on do deficit. many investigators have formulated models as an alternat...

Stream surfaces are a classic flow visualization technique used to portray the characteristics of vector fields, and texture advection research has made rapid advances in recent years. We present a novel hybrid visualization of texture advection on stream surfaces. This approach conveys properties of the vector field that stream surfaces alone cannot. We apply the visualization technique to var...

We present a new method for the realistic real-time simulation of rivers. Our solution includes a 2D fluid solver that simulates the flow of a river’s surface, an efficient method for adaptively computing 3D flow information and an animated 3D procedural wave texture that is advected through the fluid via advection particles in order to mimic the highly detailed fluid surfaces that are characte...

The issue of the parameterization of small-scale dynamics is addressed in the context of passive-scalar turbulence. The basic idea of our strategy is to identify dynamical equations for the coarse-grained scalar dynamics starting from closed equations for two-point statistical indicators. With the aim of performing a fully-analytical study, the Kraichnan advection model is considered. The white...

A novel volume-of-fluid method to simulate three-dimensional hexagonal solidification processes is presented. The Gibbs-Thomson temperature is calculated using the weighted mean curvature and a height function technique. This boundary condition is applied directly on the sharp interface. A geometric unsplit advection scheme is used to advance the interface to the next timestep. The phase change...