Laboratory Slurry Erosion Tests and Pump Wear Rate Calculations

J. J. Tuzson

doi:10.1115/1.3243089

Laboratory Slurry Erosion Tests and Pump Wear Rate Calculations

Journal of Fluids Engineering ◽

10.1115/1.3243089 ◽

1984 ◽

Vol 106 (2) ◽

pp. 135-140 ◽

Cited By ~ 33

Author(s):

J. J. Tuzson

Keyword(s):

Wear Rate ◽

Flow Pattern ◽

Field Test ◽

Test Data ◽

Three Dimensional ◽

Numerical Verification ◽

Slurry Erosion ◽

Pump Impeller ◽

Erosion Model ◽

Order Of Magnitude

From order-of-magnitude calculations, the erosion mechanism in slurry pumps for mining applications was found to be a scouring type. Impact erosion was found to be unlikely to occur. The erosion model assumes a “sliding bed” type of flow pattern and neglects the effect of turbulent diffusion of slurry particles. This choice was based on flow regime data from slurry pipeline flow and was not verified experimentally in pumps. A new centrifugal-erosion laboratory testing fixture was designed and fabricated at Allis-Chalmers which reproduces this type of erosion. Since flow conditions were closely controlled, an absolute rate of erosion could be determined. For mild steel (Rockwell C = 10) and aluminum oxide particles, a specific erosion energy of 1.5 × 108 in-lb/in3 (1000 joules/mm3) was measured. Flow pattern and slurry concentrations were calculated in a pump impeller using a quasi-three-dimensional streamline curvature method. These were combined with the above erosion model and the local erosion rate was estimated. Actual operating data had to be estimated for a quarry application of the pump because field test data was not available. The uncertainties of the field test data did not allow an exact numerical verification of the wear rate calculation, but order of magnitude agreement was obtained. The wear rate distribution agreed very well with the wear pattern observed on the impeller used in the quarry and the locations of excessive wear could be identified.

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Borehole Propagation With Undergaged Stabilizers: Theory and Validation

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.4042380 ◽

2019 ◽

Vol 141 (5) ◽

Author(s):

Umut Zalluhoglu ◽

Julien Marck ◽

Hossam Gharib ◽

Yiming Zhao

Keyword(s):

Field Test ◽

Test Data ◽

Three Dimensional ◽

Propagation Model ◽

Test Surface ◽

Propagation Modeling ◽

Proposed Model ◽

Delayed System ◽

Actual Field

This paper discusses borehole propagation modeling in the drilling industry. A three-dimensional (3D) borehole propagation model is proposed that tracks the wellbore/stabilizer contacts caused by an overgaged borehole. The resulting model represents a nonlinear delayed system that can be efficiently used to simulate borehole propagation. Simulations are provided to show the model capabilities to capture various drilling scenarios. The predictions are also validated with actual field-test data from mud-motor and rotary-steerable operations. The proposed model can be used to (a) design mud motors and rotary steerable systems (RSSs) and evaluate their steering performance, (b) design and test surface and downhole controllers for wellplan tracking, and (c) provide predictive recommendations to help directional driller operators make steering decisions while drilling.

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Detection, Averaging, and 3D Reconstruction of Biological Specimens on Hypercubes (Transputer-based) Computers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100181026 ◽

1990 ◽

Vol 48 (1) ◽

pp. 454-455

Author(s):

Jose-Maria Carazo ◽

I. Benavides ◽

S. Marco ◽

J.L. Carrascosa ◽

E.L. Zapata

Keyword(s):

3D Reconstruction ◽

3D Structure ◽

Three Dimensional ◽

Software Tools ◽

Mapping Method ◽

Computer Architectures ◽

Parallel Computer ◽

Reconstruction Process ◽

Computing Power ◽

Order Of Magnitude

Obtaining the three-dimensional (3D) structure of negatively stained biological specimens at a resolution of, typically, 2 - 4 nm is becoming a relatively common practice in an increasing number of laboratories. A combination of new conceptual approaches, new software tools, and faster computers have made this situation possible. However, all these 3D reconstruction processes are quite computer intensive, and the middle term future is full of suggestions entailing an even greater need of computing power. Up to now all published 3D reconstructions in this field have been performed on conventional (sequential) computers, but it is a fact that new parallel computer architectures represent the potential of order-of-magnitude increases in computing power and should, therefore, be considered for their possible application in the most computing intensive tasks.We have studied both shared-memory-based computer architectures, like the BBN Butterfly, and local-memory-based architectures, mainly hypercubes implemented on transputers, where we have used the algorithmic mapping method proposed by Zapata el at. In this work we have developed the basic software tools needed to obtain a 3D reconstruction from non-crystalline specimens (“single particles”) using the so-called Random Conical Tilt Series Method. We start from a pair of images presenting the same field, first tilted (by ≃55°) and then untilted. It is then assumed that we can supply the system with the image of the particle we are looking for (ideally, a 2D average from a previous study) and with a matrix describing the geometrical relationships between the tilted and untilted fields (this step is now accomplished by interactively marking a few pairs of corresponding features in the two fields). From here on the 3D reconstruction process may be run automatically.

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Scanning-tunneling spectroscopy on conjugated polymer films

MRS Proceedings ◽

10.1557/proc-771-l4.3 ◽

2003 ◽

Vol 771 ◽

Author(s):

M. Kemerink ◽

S.F. Alvarado ◽

P.M. Koenraad ◽

R.A.J. Janssen ◽

H.W.M. Salemink ◽

...

Keyword(s):

Polymer Films ◽

Conjugated Polymer ◽

Three Dimensional ◽

Field Enhancement ◽

Direct Consequence ◽

Scanning Tunneling Spectroscopy ◽

Tunneling Spectroscopy ◽

Band Alignment ◽

Scanning Tunneling ◽

Order Of Magnitude

AbstractScanning-tunneling spectroscopy experiments have been performed on conjugated polymer films and have been compared to a three-dimensional numerical model for charge injection and transport. It is found that field enhancement near the tip apex leads to significant changes in the injected current, which can amount to more than an order of magnitude, and can even change the polarity of the dominant charge carrier. As a direct consequence, the single-particle band gap and band alignment of the organic material can be directly obtained from tip height-voltage (z-V) curves, provided that the tip has a sufficiently sharp apex.

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An Alternative Method for Calculating the Eddy Current Loss in the Sleeve of a Sealless Pump

Actuators ◽

10.3390/act10040078 ◽

2021 ◽

Vol 10 (4) ◽

pp. 78

Author(s):

Tomislav Strinić ◽

Bianca Wex ◽

Gerald Jungmayr ◽

Thomas Stallinger ◽

Jörg Frevert ◽

...

Keyword(s):

Eddy Current ◽

Three Dimensional ◽

Eddy Current Loss ◽

Theoretical Background ◽

Air Gap ◽

Magnetic Flux Density ◽

Pump Impeller ◽

Current Loss ◽

Faraday’S Law ◽

Transient Simulations

A sealless pump, also known as a wet rotor pump or a canned pump, requires a stationary sleeve in the air gap to protect the stator from a medium that flows around the rotor and the pump impeller. Since the sleeve is typically made from a non-magnetic electrically conductive material, the time-varying magnetic flux density in the air gap creates an eddy current loss in the sleeve. Precise assessment of this loss is crucial for the design of the pump. This paper presents a method for calculating the eddy current loss in such sleeves by using only a two-dimensional (2D) finite element method (FEM) solver. The basic idea is to use the similar structure of Ampère’s circuital law and Faraday’s law of induction to solve eddy current problems with a magnetostatic solver. The theoretical background behind the proposed method is explained and applied to the sleeve of a sealless pump. Finally, the results obtained by a 2D FEM approach are verified by three-dimensional FEM transient simulations.

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Visualization of gas-liquid flow pattern in a centrifugal pump impeller and its influence on the pump performance

Measurement: Sensors ◽

10.1016/j.measen.2020.100033 ◽

2021 ◽

Vol 13 ◽

pp. 100033

Author(s):

Lin Zhao ◽

Zhuang Chang ◽

Zhenduo Zhang ◽

Rui Huang ◽

Denghui He

Keyword(s):

Flow Pattern ◽

Centrifugal Pump ◽

Liquid Flow ◽

Pump Impeller ◽

Pump Performance ◽

Gas Liquid Flow ◽

Centrifugal Pump Impeller

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Origin and Application of the Twinned Calcite Strain Gauge

Geosciences ◽

10.3390/geosciences11070296 ◽

2021 ◽

Vol 11 (7) ◽

pp. 296

Author(s):

Richard H. Groshong

Keyword(s):

Stress Analysis ◽

Strain Gauge ◽

Strain Tensor ◽

Three Dimensional ◽

Constant Strain Rate ◽

Axis Orientation ◽

Order Of Magnitude ◽

Rate Experiment ◽

Strain Axis ◽

Expected Values

This paper is a personal account of the origin and development of the twinned-calcite strain gauge, its experimental verification, and its relationship to stress analysis. The method allows the calculation of the three-dimensional deviatoric strain tensor based on five or more twin sets. A minimum of about 25 twin sets should provide a reasonably accurate result for the magnitude and orientation of the strain tensor. The opposite-signed strain axis orientation is the most accurately located. Where one strain axis is appreciably different from the other two, that axis is generally within about 10° of the correct value. Experiments confirm a magnitude accuracy of 1% strain over the range of 1–12% axial shortening and that samples with more than 40% negative expected values imply multiple or rotational deformations. If two deformations are at a high angle to one another, the strain calculated from the positive and negative expected values separately provides a good estimate of both deformations. Most stress analysis techniques do not provide useful magnitudes, although most provide a good estimate of the principal strain axis directions. Stress analysis based on the number of twin sets per grain provides a better than order-of-magnitude approximation to the differential stress magnitude in a constant strain rate experiment.

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Small footprint optoelectrodes using ring resonators for passive light localization

Microsystems & Nanoengineering ◽

10.1038/s41378-021-00263-0 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Vittorino Lanzio ◽

Gregory Telian ◽

Alexander Koshelev ◽

Paolo Micheletti ◽

Gianni Presti ◽

...

Keyword(s):

State Of The Art ◽

Three Dimensional ◽

Network Activity ◽

Ring Resonators ◽

Spatiotemporal Resolution ◽

Optical Ring Resonators ◽

Light Localization ◽

Order Of Magnitude ◽

Small Footprint

AbstractThe combination of electrophysiology and optogenetics enables the exploration of how the brain operates down to a single neuron and its network activity. Neural probes are in vivo invasive devices that integrate sensors and stimulation sites to record and manipulate neuronal activity with high spatiotemporal resolution. State-of-the-art probes are limited by tradeoffs involving their lateral dimension, number of sensors, and ability to access independent stimulation sites. Here, we realize a highly scalable probe that features three-dimensional integration of small-footprint arrays of sensors and nanophotonic circuits to scale the density of sensors per cross-section by one order of magnitude with respect to state-of-the-art devices. For the first time, we overcome the spatial limit of the nanophotonic circuit by coupling only one waveguide to numerous optical ring resonators as passive nanophotonic switches. With this strategy, we achieve accurate on-demand light localization while avoiding spatially demanding bundles of waveguides and demonstrate the feasibility with a proof-of-concept device and its scalability towards high-resolution and low-damage neural optoelectrodes.

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A Numerically Supported Investigation of the 3D Flow in Centrifugal Impellers: Part I — The Validation Base

Volume 1: Turbomachinery ◽

10.1115/96-gt-151 ◽

1996 ◽

Cited By ~ 1

Author(s):

Ch. Hirsch ◽

S. Kang ◽

G. Pointel

Keyword(s):

Boundary Layer ◽

Three Dimensional ◽

Boundary Layer Separation ◽

Numerical Approach ◽

Secondary Flows ◽

Pump Impeller ◽

High Loss ◽

Leakage Flows ◽

Fine Mesh ◽

Radial Pump

The three-dimensional flow in centrifugal impellers is investigated on the basis of a detailed analysis of the results of numerical simulations. In order to gain confidence in this process, an in-depth validation is performed, based on computations of Krain’s centrifugal compressor and of a radial pump impeller, both with vaneless diffusers. Detailed comparisons with available experimental data provide high confidence in the numerical tools and results. The appearance of a high loss ‘wake’ region results from the transport of boundary layer material from the blade surfaces to the shroud region and its location depends on the balance between secondary and tip leakage flows and is not necessarily connected to 3D boundary layer separation. Although the low momentum spots near the shroud can interfere with 3D separated regions, the main outcome of the present analysis is that these are two distinct phenomena. Part I of this paper focuses on the validation base of the numerical approach, based on fine mesh simulations, while Part II presents an analysis of the different contributions to the secondary flows and attempts to estimate their effect on the overall flow pattern.

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