Design and performance of a nozzle-type rainfall simulator for landslide triggering experiments

Slope deformation sensors (SDSs) were developed to monitor profiles of soil deformation at a high frequency during slope-monitoring and landslide-triggering experiments. It was hypothesized that the surface and subsurface movements could be combined to integrate the temporal development of the movements and help monitor the initiation and propagation of the shear bands indirectly, as well as predict the volume of the eventual landslide. Four SDSs were installed in a 38° slope in Northern Switzerland and slope movements due to two artificial rainfall sprinkling experiments in October 2008 and March 2009 were monitored. This paper describes the design, numerical validation, installation details, and performance of the SDSs during the first rainfall event. The data acquired from SDSs in terms of bending strain, deformation profiles, and an indication of the mechanical energy transmitted from the surrounding soil are analysed and compared with the patterns of surface movements of the slope and changes in the horizontal earth pressure. The findings are interpreted based on the applied rainfall, hydrological properties of the slope, bedrock shape, and specifications of the observed failure surface in the subsequent landslide triggering experiment. Details of the data acquired from SDSs during the second experiment in March 2009 are reported and analysed in a forthcoming paper.

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Numeric Analysis on Internal Flow of High-Speed Pump of Different Structural Style

ASME 2010 3rd Joint US-European Fluids Engineering Summer Meeting: Volume 1, Symposia – Parts A, B, and C ◽

10.1115/fedsm-icnmm2010-30405 ◽

2010 ◽

Author(s):

Hai-xia Shi ◽

Yu-jie He ◽

Jian-bo Wu ◽

Qiang Li

Keyword(s):

High Speed ◽

Static Pressure ◽

Pressure Field ◽

Computational Simulation ◽

Internal Flow ◽

Hydraulic Loss ◽

Excellent Performance ◽

Structural Style ◽

And Performance ◽

Nozzle Type

In order to study the effect of the structural style of high-speed pump on internal flow, 4 types high-speed pump of different structural style are selected for comprehensive analysis, S-A turbulence model and SIMPLIEC algorithm are adopted for numerical simulation of internal flow. By comprehensively comparing the static pressure, total pressure, sectional velocity vector and flow path line, two types of high-speed pumps with cylindrical-blade impeller matching nozzle type pump casing have relatively ideal pressure field and flow condition, can reduce hydraulic loss. The comprehensive performance of 4 types of high-speed pump is predicted through computational simulation, the high-speed pump with open cylindrical-blade impeller matching nozzle type pump casing has most excellent performance, indicating the structural style of high-speed pump has effect on its internal flow and performance.

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Technical Note: Evaluation of an Indoor Nozzle-Type Rainfall Simulator

Applied Engineering in Agriculture ◽

10.13031/2013.22689 ◽

2007 ◽

Vol 23 (3) ◽

pp. 283-287 ◽

Cited By ~ 5

Author(s):

L. N. Birt ◽

R. A. Persyn ◽

P. K. Smith

Keyword(s):

Technical Note ◽

Rainfall Simulator ◽

Nozzle Type

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Design and Performance of an In-Flight Rainfall Simulator in a Geotechnical Centrifuge

Geotechnical Testing Journal ◽

10.1520/gtj20160254 ◽

2017 ◽

Vol 41 (1) ◽

pp. 20160254 ◽

Cited By ~ 2

Author(s):

Dipankana Bhattacherjee ◽

B. V. S. Viswanadham

Keyword(s):

Rainfall Simulator ◽

Geotechnical Centrifuge ◽

And Performance

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A Revisit of Rainfall Simulator as a Potential Tool for Hydrological Research

10.5772/intechopen.93532 ◽

2020 ◽

Author(s):

Felix Gemlack Ngasoh ◽

Constantine Crown Mbajiorgu ◽

Matthew Boniface Kamai ◽

Gideon Onyekachi Okoro

Keyword(s):

Data Collection ◽

Terminal Velocity ◽

Rainfall Simulator ◽

Natural Rainfall ◽

Distribution Uniformity ◽

Hybrid Simulator ◽

Potential Tool ◽

Pressure Nozzle ◽

Nozzle Type ◽

Nozzle Spacing

Different means of hydrological data collection have developed and used. However, they are constraint in one way or other. This paper therefore revisited the rainfall simulator as potential tool for hydrological research. The research disclosed that there are three different types of rainfall simulators; drop former simulator, pressure nozzle simulator and hybrid simulator. It can further be classified as indoor model and outdoor. The research also showed that precipitation is the driving force in hydrological studies. Consequently, in the design of rainfall simulator, the following should be taken into consideration: nozzle spacing, pump size, nozzle size, nozzle type, nozzle spacing, plot size and pressure. Meanwhile, intensity, distribution uniformity, kinetic energy, rainfall drop size and rainfall terminal velocity should be noted in its evaluation. Factoring-in the aforementioned design considerations, data collection is made easy without necessarily waiting for the natural rainfall. Since the rainfall can be controlled, the erratic and unpredictable changeability of natural rainfall is eliminated. Emanating from the findings, pressurized rainfall simulator produces rainfall characteristics similar to natural rainfall, which is therefore recommended for laboratory use if natural rainfall-like characteristics is the main target.

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An approach to rainfall simulator automation and performance evaluation

Proceedings of the 10th World Congress on Intelligent Control and Automation ◽

10.1109/wcica.2012.6359040 ◽

2012 ◽

Author(s):

Jun Cai ◽

Pingkang Li ◽

Peng Wang

Keyword(s):

Performance Evaluation ◽

Rainfall Simulator ◽

And Performance

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Transmission Scanning Electron Microscopy and Energy Analysis with the Siemens ELMISKOP 101

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100095509 ◽

1972 ◽

Vol 30 ◽

pp. 450-451

Author(s):

H. M. Thieringer

Keyword(s):

Objective Lens ◽

Transmission Microscopy ◽

Image Recording ◽

Mode Of Operation ◽

Scanning Transmission ◽

Electron Microscopes ◽

And Performance ◽

Convergent Beam ◽

Ray Path ◽

Beam Diffraction

It has repeatedly been show that with conventional electron microscopes very fine electron probes can be produced, therefore allowing various micro-techniques such as micro recording, X-ray microanalysis and convergent beam diffraction. In this paper the function and performance of an SIEMENS ELMISKOP 101 used as a scanning transmission microscope (STEM) is described. This mode of operation has some advantages over the conventional transmission microscopy (CTEM) especially for the observation of thick specimen, in spite of somewhat longer image recording times.Fig.1 shows schematically the ray path and the additional electronics of an ELMISKOP 101 working as a STEM. With a point-cathode, and using condensor I and the objective lens as a demagnifying system, an electron probe with a half-width ob about 25 Å and a typical current of 5.10-11 amp at 100 kV can be obtained in the back focal plane of the objective lens.

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Angular Resolved Electron Spectroscopy with Parallel Recording

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100135459 ◽

1990 ◽

Vol 48 (2) ◽

pp. 370-371

Author(s):

Huang Min ◽

P.S. Flora ◽

C.J. Harland ◽

J.A. Venables

Keyword(s):

Electron Spectroscopy ◽

Low Voltage ◽

Solid Angle ◽

Detection System ◽

Voltage Electron ◽

Cylindrical Mirror ◽

Inner Radius ◽

Channel Plate ◽

And Performance ◽

Type Detector

A cylindrical mirror analyser (CMA) has been built with a parallel recording detection system. It is being used for angular resolved electron spectroscopy (ARES) within a SEM. The CMA has been optimised for imaging applications; the inner cylinder contains a magnetically focused and scanned, 30kV, SEM electron-optical column. The CMA has a large inner radius (50.8mm) and a large collection solid angle (Ω > 1sterad). An energy resolution (ΔE/E) of 1-2% has been achieved. The design and performance of the combination SEM/CMA instrument has been described previously and the CMA and detector system has been used for low voltage electron spectroscopy. Here we discuss the use of the CMA for ARES and present some preliminary results.The CMA has been designed for an axis-to-ring focus and uses an annular type detector. This detector consists of a channel-plate/YAG/mirror assembly which is optically coupled to either a photomultiplier for spectroscopy or a TV camera for parallel detection.

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