An experimental investigation of the effects of thawed soil depth on rill flow velocity

2021 ◽  
Vol 35 (2) ◽  
Author(s):  
Xiaofeng Gao ◽  
Xiaonan Shi ◽  
Tingwu Lei ◽  
Huaqing Liu ◽  
Jiahui Yang
Keyword(s):  
Experimental Investigation ◽  
Flow Velocity ◽  
Soil Depth ◽  
Rill Flow

Experimental Investigation of the Flow-Induced Vibrations of a Rod Cluster Control Assembly Inside Guides With Enlarged Gaps

2019 ◽  
Author(s):  
Pierre Moussou ◽  
Vincent Fichet ◽  
Luc Pastur ◽  
Constance Duhamel ◽  
Yannick Tampango
Keyword(s):  
Experimental Investigation ◽  
Flow Velocity ◽  
Nuclear Power ◽  
Axial Flow ◽  
Fretting Wear ◽  
Pressurized Water Reactor ◽  
Test Rig ◽  
Pressurized Water ◽  
Control Assembly ◽  
Control Rods

Abstract In order to better understand the mechanisms of fretting wear damage of guide cards in some Pressurized Water Reactor (PWR) Nuclear Power Plant (NPP), an experimental investigation is undertaken at the Magaly facility in Le Creusot. The test rig consists of a complete Rod Cluster with eleven Guide Cards, submitted to axial flow inside a water tunnel. In order to mimic the effect of fretting wear, the four lower guide cards have enlarged gaps, so that the Control Rods are free to oscillate. The test rig is operated at ambient temperature and pressure, and Plexiglas walls can be arranged along its upper part, and a series of camera records the vibrations of the control rods above and below the guide cards. The vertical flow velocity is in the range of a few m/s. Beam-like pinned-pinned modes at about 5 Hz are observed, and oscillations of several mm of the central rods are measured, which come along with impacts at the higher flow velocities. A simple non-linear calculation reveals that the main effect of the impacts between Control Rods and Guide Cards is an increase of the natural frequency of the rods by about 10%. Furthermore, as the vibration spectra collapse remarkably well with the flow velocity, the experiments prove that turbulent forcing is responsible for the large oscillations of the control rods, no other mechanism being involved.

Comparison of rill flow velocity over frozen and thawed slopes with electrolyte tracer method

2016 ◽  
Vol 534 ◽  
pp. 630-637 ◽  
Author(s):  
Yunyun Ban ◽  
Tingwu Lei ◽  
Zhiqiang Liu ◽  
Chao Chen
Keyword(s):  
Flow Velocity ◽  
Tracer Method ◽  
Rill Flow

Different Type Tube Bundle Heat Transfer to Vertical Foam Flow

2007 ◽  
Author(s):  
Jonas Gylys ◽  
Stasys Sinkunas ◽  
Tadas Zdankus ◽  
Vidmantas Giedraitis
Keyword(s):  
Heat Transfer ◽  
Experimental Investigation ◽  
Flow Velocity ◽  
Void Fraction ◽  
Tube Bundle ◽  
Auxiliary Equipment ◽  
Foam Flow ◽  
Flow Parameters ◽  
Tube Bundles ◽  
Foam Generator

Gas-liquid foam due to especially large inter-phase contact surface can be used as a coolant. An experimental investigation of the staggered and in-line tube bundles’ heat transfer to the vertically upward and downward laminar foam flow was performed. The experimental setup consisted of the foam generator, vertical experimental channel, tube bundles, measurement instrumentation and auxiliary equipment. It was determined dependency of heat transfer intensity on flow parameters: flow velocity, direction of flow, volumetric void fraction of foam and liquid drainage from foam. Apart of this, influence of tube position in the bundle to heat transfer was investigated. Foam flow structure, distribution of the foam’s local void fraction and flow velocity in cross-section of the channel were the main factors which influenced on heat transfer intensity of the different tubes. Experimental investigation showed that the heat transfer intensity of the frontal and further tubes of the bundles to vertical foam flow is different in comparison with one-phase fluid flow. The results of the experimental investigation are presented in this paper.

Experimental Investigation of Flow Induced Rotation of Hinged Plates With Shapes to Avoid Fluttering

2011 ◽  
Author(s):  
Antonio Carlos Fernandes ◽  
Sina Mirzaei Sefat ◽  
Fabio Moreira Coelho ◽  
Amanda Silva Albuquerque
Keyword(s):  
Experimental Investigation ◽  
Flat Plate ◽  
Flow Velocity ◽  
Natural Frequency ◽  
Dimensional Analysis ◽  
Vertical Axis ◽  
Incoming Flow ◽  
Stabilizing Effect ◽  
Plate Width ◽  
Angle Of Rotation

This paper addresses the flow induced rotation phenomena of plates hinged to allow flow induced rotating about their vertical axis. Different transversal shape configurations are studied. The aim of this study is to simplify the fluttering problem that may occur with falling objects in water during installation of offshore devices. The investigation intent is to propose an optimized configuration for stabilizing the fluttering motion of pendulous installation method of manifolds. The experiments and dimensional analysis confirmed that natural frequency is linearly proportional to the incoming flow velocity and inversely proportional to the flat plate width, and also the equivalent harmonic angle of rotation for small oscillation angles is approximately constant in different velocities. Experiments show that the bluffer plates (plate with two stabilizers and plate with stabilizers and nose), by increasing of period of rotation and also decreasing of equivalent harmonic angle of rotation have stabilizing effect in the fluttering motion of falling objects.

Noise Generated by Cavitation in Orifice Plates

1989 ◽  
Vol 111 (3) ◽  
pp. 278-289 ◽  
Author(s):  
S. R. Bistafa ◽  
G. C. Lauchle ◽  
G. Reethof
Keyword(s):  
Experimental Investigation ◽  
Flow Velocity ◽  
Dimensional Analysis ◽  
Cavitation Number ◽  
Turbulent Shear ◽  
Scaling Relations ◽  
Source Strength ◽  
Acoustic Source ◽  
Acoustic Performance ◽  
Reciprocity Method

An experimental investigation of the noise generated by cavitation in turbulent shear flows produced by confined sharp-edged orifice plates is reported. The acoustic source strength of cavitation was determined by means of reciprocity type measurements. Two experimental checks of the reciprocity method were performed. Proposed scaling relations, derived from dimensional analysis, were empirically adjusted and used to predict prototype acoustic performance based on the results of model tests. The dependence of the acoustic source strength on flow velocity and cavitation number was determined experimentally and compared with similar results reported in the literature.

Break-Up Length and Spreading Angle of Liquid Sheets Formed by Splash Plate Nozzles

2008 ◽  
Vol 131 (1) ◽  
Author(s):  
M. Ahmed ◽  
N. Ashgriz ◽  
H. N. Tran
Keyword(s):  
Experimental Investigation ◽  
Flow Velocity ◽  
Liquid Sheet ◽  
Operating Conditions ◽  
Nozzle Diameter ◽  
Empirical Correlation ◽  
Liquid Viscosity ◽  
Liquid Sheets ◽  
Break Up ◽  
Semi Empirical

An experimental investigation is conducted to determine the effect of liquid viscosity and density, nozzle diameter, and flow velocity on the break-up length and spreading angle of liquid sheets formed by splash plate nozzles. Various mixtures of corn syrup and water were used to obtain viscosities in the range of 1–170 mPa s. Four different splash plate nozzle diameters of 0.5 mm, 0.75 mm, 1 mm, and 2 mm, with a constant plate angle of 55 deg were tested. The liquid sheet angles and the break-up lengths were measured at various operating conditions. An empirical correlation for the sheet spreading angle and a semi-empirical correlation for the sheet break-up lengths are developed.

Effect of Oil Flow Velocity on Hydraulic Shock

2015 ◽  
Vol 752-753 ◽  
pp. 896-901
Author(s):  
Adam Bureček ◽  
Lumír Hružík ◽  
Martin Vašina
Keyword(s):  
Experimental Investigation ◽  
Flow Velocity ◽  
Stationary Flow ◽  
Hydraulic Shock ◽  
Oil Flow

The article is focused on experimental investigation of oil dynamics in long pipe at non-stationary flow. The non-stationary flow is realized by sudden closing of seat valve at the end of the long pipe. For this reason the oil pressure is suddenly increased and hydraulic shock is created. There is described the influence of oil flow velocity on hydraulic shock in this article. The pressure is measured near the seat valve. Furthermore this process is mathematically simulated using Matlab SimHydraulics software and is compared with the experiment.

Sign in / Sign up

Export Citation Format

Share Document