We measure the flow of granular materials inside a quasi-two-dimensional silo as it drains and compare the data with some existing models. The particles inside the silo are imaged and tracked with unprecedented resolution in both space and time to obtain their velocity and diffusion properties. The data obtained by varying the orifice width and the hopper angle allow us to thoroughly test model...

This paper reports an improvement of the particle-excitation flow control valve. The valve that we have designed in previous reports can control air flow, using particle excitation by piezoelectric resonance, and has the following advantages: small size, lightweight, high response and continuous airflow control. However, in our previous models, the relationship between the driving voltage and t...

3D color Doppler echocardiography has recently been employed to evaluate 3D proximal isovelocity surface area (PISA) and vena contracta (VC) area measures of regurgitant valve severity. Computational fluid dynamics (CFD) modeling may provide insight into the strengths and limitations of emerging 3D color Doppler applications for the quantification of mitral regurgitation (MR). The objective of ...

Monodisperse poly(DL-lactic acid) (PLA) particles of diameters between 11 and 121 μm were fabricated in flow focusing glass microcapillary devices by evaporation of dichloromethane (DCM) from emulsion droplets at room temperature. The dispersed phase was 5% (w/w) PLA in DCM containing 0.1-2 mM Nile Red and the continuous phase was 5% (w/w) poly(vinyl alcohol) in reverse osmosis water. Particle ...

A consolidation of literature indicating the advances in the field of mass flow measurement is presently not available. Last published review paper on Coriolis mas flow meter (CFM) was in 2006. This work is an attempt is made to summarize the available works on Coriolis mass flow meter. The literature is classified into three major groups. The first group gives the summary of construction and t...

PURPOSE The goals of this investigation were to evaluate the accuracy and reliability of the Angioflow meter system with use of in vitro and in vivo methods and to compare it to the standard Transonics HD01 system in a clinical setting. MATERIALS AND METHODS The Angioflow meter system consists of a 6-F endovascular catheter and a laptop computer containing proprietary software for this applic...

To determine the source of errors in the Gorlin formula for estimating stenotic valvular orifice area, we used a pulsatile flow model that emulated left ventricular and aortic pressures and flow and allowed control of ventricular outflow orifice area. After comparing orifice areas calculated by the Gorlin formula with actual orifice areas, the Gorlin formula constant (k) was found to be highly ...

Objectives. This study investigated the proximal centerline flow convergence region simultaneously by both color Doppler and laser Doppler velocimetry. Background. Although numerous investigations have been performed to test the flow convergence method, to our knowledge there has yet been no experimental study using reference standard velocimetric techniques to define precisely the hydrodynamic...

Because aortic stenosis results in the loss of left ventricular stroke work (due to resistance to flow through the valve and turbulence in the aorta), the percentage of stroke work that is lost may reflect the severity of stenosis. This index can be calculated from pressure data alone. The relation between percent stroke work loss and anatomic aortic valve orifice area (measured by planimetry f...