Simulation for a Floating Roof Behavior of Cylindrical Storage Tank due to Wind Load: Part 1 — CFD Analysis

2012 ◽  
Author(s):  
Shinichi Kuroda ◽  
Hidesaku Uejima ◽  
Kazuo Ishida ◽  
Shoichi Yoshida ◽  
Masaki Shiratori ◽  
...  
Keyword(s):  
Pressure Fluctuation ◽  
Storage Tank ◽  
Fatigue Cracks ◽  
Flow Simulation ◽  
Wind Load ◽  
Sea Surface ◽  
Dynamic Mode Decomposition ◽  
Dynamic Mode ◽  
Wind Flow ◽  
Oil Storage

Floating roofs are used in large cylindrical storage tanks to prevent evaporation of oil. The floating roof is said to vibrate in high winds like undulation of the sea surface. The wind induced, sea-surface-undulation-like vibration may initiate fatigue cracks at welded joints in the floating roof deck. In this two-part study, the authors attempted to simulate the vibration. In Part1 wind flow over an isolated cylindrical oil-storage tank was simulated without considering the motion of the roof. Computed unsteady pressure load data were transferred to structural analyses. Response analyses of the floating roof under the wind load are dealt with in Part2. The present paper describes the wind flow simulation. The computed pressure fluctuation over the roof exhibits broadband spectra and no remarkable dominant frequency. To gain some insights into characteristics of the roof pressure fluctuation and its association with global flow structures, the Snapshot Proper Orthogonal Decomposition (POD), the Dynamic Mode Decomposition (DMD), and the Complex POD were applied.

Simulation for a Floating Roof Behavior of Cylindrical Storage Tank due to Wind Load: Part 2 — Sloshing Response Analysis

2012 ◽  
Author(s):  
Shoichi Yoshida ◽  
Shinichi Kuroda ◽  
Hidesaku Uejima ◽  
Kazuo Ishida ◽  
Masaki Shiratori ◽  
...  
Keyword(s):  
Storage Tank ◽  
Fatigue Cracks ◽  
Wind Load ◽  
Vibration Characteristics ◽  
Response Analysis ◽  
Cfd Analysis ◽  
Element Analysis ◽  
Linear Elastic ◽  
Deck Plate ◽  
The Waves

The floating roofs are used in large cylindrical storage tanks to prevent evaporation of oil. The single-deck floating roof, considered herein, consists of a thin circular plate called “deck” attached to a buoyant ring of box-shaped cross section called “pontoon”. The deck plates are deformed to create waves and they are subjected to cyclic bending due to wind load. This phenomenon may lead to initiate fatigue cracks at the welding joints. It is important to know the vibration characteristics of the waves in the deck plate. The authors have reported a CFD analysis of a cylindrical storage tank due to uniform wind flow in another paper. This paper presents the axisymmetric finite element analysis for the sloshing response of the single-deck floating roofs in a cylindrical storage tank subjected to wind load obtained by the CFD analysis. It is assumed that the liquid is incompressible and inviscid, and the roof is linear elastic while the sidewall and the bottom are rigid. The basic vibration characteristics of the waves in the deck plate, such as frequency and amplitude, are investigated.

scholarly journals Installation of physical simulation of wind load on crane structures

2021 ◽  
Vol 24 (6) ◽  
pp. 1199-1208
Author(s):  
L. A. Sladkova ◽  
V. V. Krylov ◽  
F. A. Kuznetsov
Keyword(s):  
Computer Model ◽  
Physical Simulation ◽  
Flow Simulation ◽  
Dynamic Effect ◽  
Wind Load ◽  
Operating Conditions ◽  
Model Parameters ◽  
Wind Flow ◽  
Operation Conditions ◽  
The Impact

The purpose of the paper is to reproduce a standard wind flow (laminar, turbulent, pulsating modes) to study the impact on crane structures, with the aim to obtain the load values of crane elements most closely approximate to real conditions. When creating an installation, which is related to the field of experimental aerodynamics, the "principle of simulating the main factors determined by the operating conditions of the research object" is adopted to ensure the r eproducibility of test results to the maximum extent. To confirm the performance efficiency of the proposed installation device, its computer model is developed using the CAD software SolidWorks. The computer model parameters are in full geometric agreement with the dimensions of the developed real installation. The use of the installation makes it possible to study the dynamic effect of the wind on the stability of crane structures in various operation modes (change in wind speed, in the mode of load operation, in operation conditions at the wall, etc.). The proposed installation allows to simulate the loads on crane equipment with the possibility of characteristics expanding, for example, its carrying capacity. The generated computer model of the installation makes it possible to reveal the physical picture of wind flow distribution at the installation outlet. The results of wind flow simulation on the proposed installation are confirmed on a computer model with a high degree of convergence of results at wind speeds of 2.5 m/s and lower The installation proposed by the authors will allow to simulate: the value of the real average statistical wind load of various intensity; pulsating component of the wind load; vortex excitation; increase of the available aerodynamic research capability for a real crane structure. The developed installation is a calibration device for external impacts of the wind force on the crane structure.

Experimental Measurement of In-Plane Rolling Nonpneumatic Tire Vibrations Using High-Speed Imaging

2019 ◽  
Vol 47 (3) ◽  
pp. 196-210
Author(s):  
Meghashyam Panyam ◽  
Beshah Ayalew ◽  
Timothy Rhyne ◽  
Steve Cron ◽  
John Adcox
Keyword(s):  
High Speed ◽  
Image Correlation ◽  
Dynamic Mode Decomposition ◽  
Dynamic Mode ◽  
High Speed Imaging ◽  
Correlation Algorithm ◽  
Mode Decomposition ◽  
Series Of Experiments ◽  
Plane Deformations ◽  
Dominant Frequencies

ABSTRACT This article presents a novel experimental technique for measuring in-plane deformations and vibration modes of a rotating nonpneumatic tire subjected to obstacle impacts. The tire was mounted on a modified quarter-car test rig, which was built around one of the drums of a 500-horse power chassis dynamometer at Clemson University's International Center for Automotive Research. A series of experiments were conducted using a high-speed camera to capture the event of the rotating tire coming into contact with a cleat attached to the surface of the drum. The resulting video was processed using a two-dimensional digital image correlation algorithm to obtain in-plane radial and tangential deformation fields of the tire. The dynamic mode decomposition algorithm was implemented on the deformation fields to extract the dominant frequencies that were excited in the tire upon contact with the cleat. It was observed that the deformations and the modal frequencies estimated using this method were within a reasonable range of expected values. In general, the results indicate that the method used in this study can be a useful tool in measuring in-plane deformations of rolling tires without the need for additional sensors and wiring.

Oscillatory flow around a vertical wall-mounted cylinder: Dynamic mode decomposition

2021 ◽  
Vol 33 (2) ◽  
pp. 025113
Author(s):  
H. K. Jang ◽  
C. E. Ozdemir ◽  
J.-H. Liang ◽  
M. Tyagi
Keyword(s):  
Oscillatory Flow ◽  
Vertical Wall ◽  
Dynamic Mode Decomposition ◽  
Dynamic Mode ◽  
Mode Decomposition

Modeling the Turbulent Wake Behind a Wall-Mounted Square Cylinder

2020 ◽  
Author(s):  
Christian Amor ◽  
José M Pérez ◽  
Philipp Schlatter ◽  
Ricardo Vinuesa ◽  
Soledad Le Clainche
Keyword(s):  
Proper Orthogonal Decomposition ◽  
Turbulent Wake ◽  
Orthogonal Decomposition ◽  
Dynamic Mode Decomposition ◽  
Dynamic Mode ◽  
Square Cylinder ◽  
Complex Flow ◽  
Reduced Order ◽  
Mode Decomposition ◽  
Proper Orthogonal

Abstract This article introduces some soft computing methods generally used for data analysis and flow pattern detection in fluid dynamics. These techniques decompose the original flow field as an expansion of modes, which can be either orthogonal in time (variants of dynamic mode decomposition), or in space (variants of proper orthogonal decomposition) or in time and space (spectral proper orthogonal decomposition), or they can simply be selected using some sophisticated statistical techniques (empirical mode decomposition). The performance of these methods is tested in the turbulent wake of a wall-mounted square cylinder. This highly complex flow is suitable to show the ability of the aforementioned methods to reduce the degrees of freedom of the original data by only retaining the large scales in the flow. The main result is a reduced-order model of the original flow case, based on a low number of modes. A deep discussion is carried out about how to choose the most computationally efficient method to obtain suitable reduced-order models of the flow. The techniques introduced in this article are data-driven methods that could be applied to model any type of non-linear dynamical system, including numerical and experimental databases.

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