The purpose of this study was to establish valid indexes of conduit and resistance vessel structure in humans by using edge detection and wall tracking of high-resolution B-mode arterial ultrasound images, combined with synchronized Doppler waveform envelope analysis, to calculate conduit artery blood flow and diameter continuously across the cardiac cycle. Nine subjects aged 36.7 (9.2) yr unde...

Numerical solutions using finite element methods are considered for transient flow in a porous medium coupled to free flow in embedded conduits. Such situations arise, for example, for groundwater flows in karst aquifers. The coupled flow is modeled by the Darcy equation in a porous medium and the Stokes equations in the conduit domain. On the interface between the matrix and conduit, Beavers–J...

This present paper presents a lattice approach to model the influence of cracking on flow in concrete. An earlier mechanical lattice model based on the Voronoi tesselation with a damage-plasticity constitutive model was combined with a new dual lattice of conduit elements for flow analysis. The diffusivity of the conduit elements depends on the crack-opening obtained from the mechanical lattice...

Youxue Zhang Department of Geological Sciences, University of Michigan, Ann Arbor, MI 48109–1063, USA Fax: c1(734) 763 4690 e-mail: [email protected] Abstract Simulated gas-driven eruptions using CO2–water-polymer systems are reported. Eruptions are initiated by rapidly decompressing CO2–saturated water containing up to 1.0 wt.% CO2. Both cylindrical test cells and a flask test cell were used to...

We evaluated whether patterns in hydraulic architecture increase transport efficiency. Five patterns are identified: area-preserving branching; variable trunk versus twig sap velocity; distally decreasing leaf specific conductivity (K(L)) and conduit diameter; and a decline in leaf specific conductance (k(L)) of the entire plant with maturation. These patterns coexist in innumerable combination...

This paper presents a lattice approach to model the influence of cracking on inviscid flow in concrete. A mechanical lattice model based on a damage-plasticity constitutive model was combined with a new dual lattice of conduit elements for flow analysis. The diffusivity of the conduit elements depends on the crack-opening obtained from the mechanical lattice. The coupled lattice model was appli...