K-1229 Turbulence-Induced Fluid Dynamic Forces Acting on Cross-Shaped Tube Bundle in Cross Flow : Part 2 : Measurement in the High Reynolds Number

2001 ◽  
Vol V.01.1 (0) ◽  
pp. 139-140
Author(s):  
Takashi NISHIHARA ◽  
Nobukazu TANAKA ◽  
Fumio INADA ◽  
Akira YASUO ◽  
Shinichi KAWAMURA ◽  
...  
Keyword(s):  
Reynolds Number ◽  
High Reynolds Number ◽  
Tube Bundle ◽  
Fluid Dynamic ◽  
Cross Flow ◽  
Shaped Tube ◽  
Dynamic Forces ◽  
Flow Part ◽  
High Reynolds

K-1228 Turbulence-Induced Fluid Dynamic Forces Acting on Cross-Shaped Tube Bundle in Cross Flow : Part 1 : Cross-Correlation due to Small Scale Test

2001 ◽  
Vol V.01.1 (0) ◽  
pp. 137-138
Author(s):  
Fumio INADA ◽  
Akira YASUO ◽  
Takashi NISHIHARA ◽  
Kimitoshi YONEDA ◽  
Shinichi KAWAMURA ◽  
...  
Keyword(s):  
Cross Correlation ◽  
Tube Bundle ◽  
Fluid Dynamic ◽  
Cross Flow ◽  
Small Scale ◽  
Shaped Tube ◽  
Dynamic Forces ◽  
Flow Part ◽  
Scale Test

Turbulence-Induced Fluid Dynamic Forces Acting on Cross-Shaped Tube Bundle in Cross Flow

2002 ◽  
Author(s):  
Takashi Nishihara ◽  
Fumio Inada ◽  
Akira Yasuo ◽  
Ryo Morita ◽  
Akihiro Sakashita ◽  
...  
Keyword(s):  
Tube Bundle ◽  
Fluid Dynamic ◽  
Cross Flow ◽  
Scale Model ◽  
Small Scale ◽  
Power Spectral ◽  
Shaped Tube ◽  
Dynamic Forces ◽  
Excitation Force ◽  
Small Scale Model

A cross-shaped tube bundle with dense arrangement may be designed for a lower plenum structure in a next generation LWR, though the characteristics of flow-induced vibration of this type of tube bundle remain virtually unknown. In this study, turbulence-induced fluid dynamic forces acting on a cross-shaped tube bundle with a dense arrangement subject to cross flow were measured by water tunnel tests with two types of scale models. One is a small-scale model to measure local fluid dynamic forces and their correlation length in the lift and drag direction. The other is a large-scale model to investigate the effect of the Reynolds number on fluid dynamic forces in the lift, drag and torsional directions. Free oscillation tests with another small-scale model were also conducted to measure vibration amplitude by random excitation force. In conclusion, the following results were obtained. Vortex-induced vibration cannot arise in the cross-shaped tube bundle, since a typical peak corresponding to periodic vortex shedding was not observed in power spectral density for fluid excitation force. Power spectral densities of fluid dynamic forces in the drag, lift and torsional directions have mutually similar properties and they are hardly dependent on the Reynolds number. The experimental results were compiled into dimensionless correlation equations composed of the power spectral density for the local fluid excitation force and its correlation length. They are useful for evaluating the random vibration amplitude. The estimated amplitudes of turbulence-induced vibration by the correlation equation coincide with those of the experimental results obtained by the free-oscillation tests.

Turbulence-induced fluid dynamic forces acting on cross-shaped tube bundle in cross-flow

2003 ◽  
Vol 18 (5) ◽  
pp. 635-650 ◽  
Author(s):  
T. Nishihara ◽  
F. Inada ◽  
A. Yasuo ◽  
R. Morita ◽  
A. Sakashita ◽  
...  
Keyword(s):  
Tube Bundle ◽  
Fluid Dynamic ◽  
Cross Flow ◽  
Shaped Tube ◽  
Dynamic Forces

scholarly journals Numerical Investigation of the Flow around a Feather Shuttlecock with Rotation

Proceedings ◽  
2020 ◽  
Vol 49 (1) ◽  
pp. 28
Author(s):  
John Hart ◽  
Jonathan Potts
Keyword(s):  
Reynolds Number ◽  
Wind Tunnel ◽  
Drag Coefficient ◽  
Numerical Investigation ◽  
Computational Fluid Dynamic ◽  
High Reynolds Number ◽  
Fluid Dynamic ◽  
Flow Structures ◽  
Drag Forces ◽  
High Reynolds

This paper presents the first scale resolving computational fluid dynamic (CFD) investigation of a geometrically realistic feather shuttlecock with rotation at a high Reynolds number. Rotation was found to reduce the drag coefficient of the shuttlecock. However, the drag coefficient is shown to be independent of the Reynolds number for both rotating and statically fixed shuttlecocks. Particular attention is given to the influence of rotation on the development of flow structures. Rotation is shown to have a clear influence on the formation of flow structures particularly from the feather vanes, and aft of the shuttlecock base. This further raises concerns regarding wind tunnel studies that use traditional experimental sting mounts; typically inserted into this aft region, they have potential to compromise both flow structure and resultant drag forces. As CFD does not necessitate use of a sting with proper application, it has great potential for a detailed study and analysis of shuttlecocks.

Self-Excited Vibration of Cross-Shaped Tube Bundle in Cross Flow

2002 ◽  
Author(s):  
Fumio Inada ◽  
Takashi Nishihara ◽  
Akira Yasuo ◽  
Ryo Morita ◽  
Akihiro Sakashita ◽  
...  
Keyword(s):  
Reynolds Number ◽  
Large Scale ◽  
Tube Bundle ◽  
Cross Flow ◽  
Small Scale ◽  
Design Guideline ◽  
Shaped Tube ◽  
Excited Vibration ◽  
Scale Test ◽  
Flexible Tubes

Cross-shaped tube bundle is proposed for a lower plenum structure in a next generation LWR. Vibration response of cross-shaped tube bundle in cross flow has been measured in water tunnel tests. First, small-scale test was conducted. Tests were conducted with 3×3 flexible tubes as well as single flexible tube in rigid tube bundle. The flexible tubes could vibrate in lift, drag, and torsional direction. The effect of arrangements of tube bundle and the natural frequency ratio of bending and torsional vibrations were considered. Second, a large-scale test was conducted for only one case to check the effect of Reynolds number, in which Reynolds number was 10 times larger than that of small-scale test. In all the cases, large amplitude vibration could appear when the flow velocity became larger than a critical value, and a self-excited vibration was found to occur. The nondimensional critical gap velocity of the large-scale test agreed well with that of the small-scale test, which suggested that the effect of Reynolds number was not so large. A design guideline to prevent self-excited vibration was proposed for cross-shaped tube bundle.

A Calibration of a Feedwater Flowmeter Installed to Model Loop of a Nuclear Power Plant Using High Reynolds Number Facility

2008 ◽  
Author(s):  
Noriyuki Furuichi ◽  
Yoshiya Terao ◽  
Masaki Takamoto
Keyword(s):  
Reynolds Number ◽  
Power Plant ◽  
Nuclear Power Plant ◽  
Nuclear Power ◽  
High Reynolds Number ◽  
Tube Bundle ◽  
Three Dimensional ◽  
Calibration Result ◽  
Calibration Facility ◽  
High Reynolds

A calibration result of ultrasonic flowmeters using in a feedwater flowrate in a nuclear power plant, is described under a variety of upstream conditions using the new high Reynolds number calibration facility. The pipe layouts are classified to five type three-dimensional one with two or three elbows. The flow conditioners are tube bundle type and Mitsubishi type. Pipe Reynolds number is up to 1.6×107. The large effect of the flow conditioner and pipe layout is observed for cramp-on type. For multi-path type, individuality is observed.

scholarly journals Trajectory of a synthetic jet issuing into high-Reynolds-number turbulent boundary layers

2018 ◽  
Vol 856 ◽  
pp. 531-551 ◽  
Author(s):  
Tim Berk ◽  
Nicholas Hutchins ◽  
Ivan Marusic ◽  
Bharathram Ganapathisubramani
Keyword(s):  
Reynolds Number ◽  
Boundary Layers ◽  
High Reynolds Number ◽  
Velocity Ratio ◽  
Cross Flow ◽  
Turbulent Boundary Layers ◽  
Synthetic Jet ◽  
Actuation Frequency ◽  
The Cross ◽  
High Reynolds

Synthetic jets are zero-net-mass-flux actuators that can be used in a range of flow control applications. For some applications, the scaling of the trajectory of the jet with actuation and cross-flow parameters is important. This scaling is investigated for changes in the friction Reynolds number, changes in the velocity ratio (defined as the ratio between the mean jet blowing velocity and the free-stream velocity) and changes in the actuation frequency of the jet. A distinctive aspect of this study is the high-Reynolds-number turbulent boundary layers (up to $Re_{\unicode[STIX]{x1D70F}}=12\,800$) of the cross-flow. To our knowledge, this is the first study to investigate the effect of the friction Reynolds number of the cross-flow on the trajectory of an (unsteady) jet, as well as the first study to systematically investigate the scaling of the trajectory with actuation frequency. A broad range of parameters is varied (rather than an in-depth investigation of a single parameter) and the results of this study are meant to indicate the relative importance of each parameter rather than the exact influence on the trajectory. Within the range of parameters explored, the critical ones are found to be the velocity ratio as well as a non-dimensional frequency based on the jet actuation frequency, the cross-flow velocity and the jet dimensions. The Reynolds number of the boundary layer is shown to have only a small effect on the trajectory. An expression for the trajectory of the jet is derived from the data, which (in the limit) is consistent with known expressions for the trajectory of a steady jet in a cross-flow.

Sign in / Sign up

Export Citation Format

Share Document