Modeling of free surface flow in a helical channel with finite pitch

The laminar fully developed free surface flow in a helical channel with finite pitch and rectangular section is modeled. The mass and momentum conservation equations are written in a local orthogonal system and solved numerically using the finite volume method The free surface position, determined using the height of liquid method compares favorably against the experimental data. The main and secondary velocity fields are determined as well as the friction factor for Reynolds number ranging from 352 to 856.29434535

Photonic crystal fibers as miniature monitoring platforms for petroleum characterization

A fiber design that allows the characterization of high and low refractive index materials is proposed and demonstrated. This fiber consists of an air-silica photonic crystal fiber supporting a Gaussian like mode confined in the fiber core and a ring mode in a region between the structured area and the fiber cladding. This versatile fiber design finds applications in the oil industry where materials of different refractive indices are found. The characterization of petroleum and CO2 using the new fiber is demonstrated. © 2012 SPIE

Experimental and numerical development of a two-phase Venturi flow meter

An algebraic model is developed access the gas and the liquid flow rates of a two-phase mixture through a Venturi tube. The flow meter operates with upward bubbly flows with low gas content, i.e., volumetric void fraction bellow 12%. The algebraic model parameters stem from numerical modeling and its output is checked against the experimental values. An indoor test facility operating with air-water and air-glycerin mixtures in a broad range of gas and liquid flow rates reproduces the upward bubbly flow through the Venturi tube. Measurements of gas and liquid flow rates plus the static pressure acroos the Venturi constitute the experimental database. The numerical flow modeling uses the isothermal, axis-symmetric with no phase change representation of the Two-Fluid model. The numerical output feeds the Venturi's algebraic model with the proper constants and parameters embodying the two-phase flow physics. The novelty of this approach is the development of each flow meter model accordingly to its on characteristics. The flow predictions deviates less than 14% from experimental data while the mixture pipe Reynolds number spanned front 500 to 50, 000.126345746

Modeling fully developed laminar flow in a helical duct with rectangular cross section and finite pitch

The mass and momentum transport equations are written in an orthogonal coordinate system using Germano's transformation to model a laminar flow in a helical duct with a rectangular cross section and finite pitch. The system of governing equations are discretized and solved by the finite-volume numerical method. The three dimensional domain is reduced to a two dimensional slab of cells. orthogonal to the main flow direction, enforcing the fully developed state for 2 pi/(tau.d(h)) >> 1 where tau and d(h) representing the duct's center-line torsion and its hydraulic diameter. This approximation and the use of an orthogonal grid allow a great simplification on the numerical procedure. Comparisons of the numerical solution against experimental data are drawn to assess the accuracy of the approximation. Crown Copyright (C) 2011 Published by Elsevier Inc. All rights reserved.36105059506

The architecture of complexity

In this paper we reflect on organizational space and its implications for organization and management. In contrast to dominant discourse in management and organization theory we address the ways in which corporate buildings, as social objects, provide a materiality to organization. Developing the concept of the architecture of complexity, we focus on space as the precondition of processes of organizing. The productive power of space lies in its potential to create and trigger complexity, as it pre-structures movement and flows of communication. Reflecting on two concrete spatial organizations (the fold and heterotopia) we suggest that the interplay of order and disorder and inside/outside relation, which these spaces provide, are spatial preconditions of organizational change and creativity