Experimental investigation of the stress and particle velocity fields associated with explosions in frozen soils

1969 ◽  
Vol 3 (1) ◽  
pp. 80-86
Author(s):  
Yu. Ya. Trukhanov
Keyword(s):  
Experimental Investigation ◽  
Particle Velocity ◽  
Velocity Fields ◽  
Frozen Soils

Effect of Erosive Particle Velocity on the Intensity of Polymeric Coating Wear

2010 ◽  
Vol 165 ◽  
pp. 91-96 ◽  
Author(s):  
Danuta Kotnarowska
Keyword(s):  
Experimental Investigation ◽  
Grain Size ◽  
Particle Velocity ◽  
Erosive Wear ◽  
Wear Intensity ◽  
Polymeric Coating ◽  
Degree Polynomial ◽  
Acrylic Coating ◽  
The Moment ◽  
Free Falling

The paper deals with experimental investigation of erosive wear of acrylic coating. The research was carried out on the erosive wear under the influence of alundum particles (grain size of 0.6 – 0.7 mm) striking the coatings at the angle of 45 degrees. It was established that intensity of the erosive wear (under the influence of free falling alundum particles) essentially depends on velocity of erosive particle at the moment of its impact against coating surface. For example, for the lowest velocity value (3.6 m/s) at the moment of impact, erosive wear intensity was equal to 0.4 mm/kg, while for the largest velocity value (5.3 m/s), the intensity doubled in magnitude. The characteristic of erosive wear intensity, depending on erosive particle velocity, was generated by using second-degree polynomial.

scholarly journals On the use of acoustic particle velocity fields in adjoint‐based inversion

2006 ◽  
Vol 120 (5) ◽  
pp. 3356-3356
Author(s):  
Matthias Meyer ◽  
Jean‐Pierre Hermand ◽  
Kevin B. Smith
Keyword(s):  
Particle Velocity ◽  
Velocity Fields

Mechanical behavior of frozen soils: Experimental investigation and numerical modeling

2021 ◽  
Vol 138 ◽  
pp. 104361
Author(s):  
Ajay Shastri ◽  
Marcelo Sánchez ◽  
Xuerui Gai ◽  
Moo Y. Lee ◽  
Thomas Dewers
Keyword(s):  
Experimental Investigation ◽  
Numerical Modeling ◽  
Mechanical Behavior ◽  
Frozen Soils

Ultrasonic Measurements of Local Particle Velocity and Concentration Within the Casing of a Centrifugal Pump

2015 ◽  
Author(s):  
John M. Furlan ◽  
Mohamed Garman ◽  
Jaikrishnan Kadambi ◽  
Robert J. Visintainer ◽  
Krishnan V. Pagalthivarthi
Keyword(s):  
Centrifugal Pump ◽  
Particle Velocity ◽  
Volume Fraction ◽  
Side Wall ◽  
Velocity Fields ◽  
Solid Particles ◽  
Acoustic Properties ◽  
Soda Lime Glass ◽  
Calibration Data ◽  
Slurry Flows

In the design of slurry transport equipment used in the mining and dredging industries, the effects of solid particle velocity and concentration on hydraulic performance and wear need to be considered. Two ultrasonic techniques have been used to investigate slurry flows through a centrifugal pump casing: a local particle concentration measurement technique (Furlan et al., 2012) and a pulsed ultrasonic Doppler Velocimetry (PUDV) technique (Hanjiang, 2003, Garman, 2015). Local particle velocities and concentrations have been obtained in a flow of soda lime glass particles (diameter of 195 μm) and water through the casing of a centrifugal slurry pump operating close to the best efficiency point using the two ultrasound techniques. For the concentration measurements, the acoustic properties of slurry flows such as sonic velocity, backscatter, and attenuation are correlated to the volume fraction of solid particles. The algorithm utilizes measurements obtained from homogeneous vertical pipe flow fields as calibration data in order to obtain experimental concentration profiles in the non-homogenous flow regimes which are encountered in the pump casing. The PUDV technique correlates the Doppler shift in frequency associated with the movement of particles towards or away from the transducer. A two measurement (angle) technique is applied within the pump casing in order to account for the components of particle velocity which are orthogonal to the casing side wall. The techniques are utilized to obtain concentration and velocity profiles within the pump casing for overall average loop particle concentrations ranging from 7–11 % by volume. The experimental results are compared with the concentration and velocity fields that are predicted by in-house finite element computational fluid dynamics (CFD) codes (Pagalthivarthi and Visintainer, 2009) which are used to predict wear in centrifugal slurry pump wet end components. Reasonable agreement is observed for both the concentration and velocity fields. Specifically, measurements indicate that there is a reduction of in-situ concentration and hence a corresponding radial acceleration of the particles with respect to the fluid occurring within the impeller which has also been predicted by computational predictions of flow through the impeller (Pagalthivarthi et al., 2013). Additionally, the prediction of the existence of secondary flow patterns by the casing computational code has been supported with the velocity measurements.

Resonance of Trapped Acoustic Modes of a Ducted Rectangular Cavity

2015 ◽  
Author(s):  
Michael Bolduc ◽  
Samir Ziada ◽  
Philippe Lafon
Keyword(s):  
Shear Layer ◽  
Particle Velocity ◽  
Acoustic Mode ◽  
Velocity Fields ◽  
Mode Shapes ◽  
Test Results ◽  
Trapped Modes ◽  
Cross Sectional ◽  
Acoustic Modes ◽  
Axisymmetric Cavities

Flow over ducted cavities can lead to strong resonances of the trapped acoustic modes due to the presence of the cavity within the duct. Aly & Ziada [1–3] investigated the excitation mechanism of acoustic trapped modes in axisymmetric cavities. These trapped modes in axisymmetric cavities tend to spin because they do not have preferred orientation. The present paper investigates rectangular cross-sectional cavities as this cavity geometry introduces an orientation preference to the excited acoustic mode. Three cavities are investigated, one of which is square while the other two are rectangular. In each case, numerical simulations are performed to characterize the acoustic mode shapes and the associated acoustic particle velocity fields. The test results show the existence of stationary modes, being excited either consecutively or simultaneously, and a particular spinning mode for the cavity with square cross-section. The computed acoustic pressure and particle velocity fields of the excited modes suggest complex oscillation patterns of the cavity shear layer because it is excited, at the upstream corner, by periodic distributions of the particle velocity along the shear layer circumference.

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