Numerical simulation and experiment investigation on passive-suction-jet control of wind effect of two tandem cable models

2020 ◽  
pp. 136943322097179
Author(s):  
Wen-Li Chen ◽  
Yan-Jiao Guo ◽  
Xiang-Wei Min ◽  
Hui Li
Keyword(s):  
Numerical Simulation ◽  
Control Method ◽  
Suspension Bridge ◽  
Flow Fields ◽  
Flow Patterns ◽  
Wind Effect ◽  
Long Span ◽  
Spacing Ratio ◽  
Vibration Responses ◽  
Jet Control

Two tandem cables are frequently employed as one group of hangers in a long-span suspension bridge; however, if they are close to each other, the mutual interaction between their flow fields is prone to produce large wind/wake-induced vibrations. In the present study, initially, a numerical simulation was conducted to investigate the interaction between two static tandem cable models with different spacing ratios, SR (center-to-center longitudinal spacing divided by the cable diameter, i.e. L/D). Concurrently, the passive-suction-jet control method was employed to eliminate the interaction of these two tandem cables. Aerodynamic coefficients and time-averaged and instantaneous flow fields were used to evaluate the effectiveness of the passive-suction-jet control. Subsequently, the passive-suction-jet control method was employed in a wind tunnel experiment to manipulate the wind-induced vibrations of two elastically mounted cable models. The flow patterns of the controlled tandem cables were subdivided into three basic regimes in the present study. Furthermore, the aerodynamics force suppression mechanism was explained based on the flow patterns. Both the aerodynamic forces and vibration responses of the tandem cable models reduced significantly when SR >  SRc (critical spacing ratio). Particularly for SR = 4.0, the lift fluctuation reduction of both the cable models was remarkable, the fluctuating lifts of the upstream and downstream cable models decreased by 93.3% and 72.1%, respectively, and the vortex-induced vibration responses decreased by 31.4% and 54.0% respectively. Furthermore, the wake-induced vibration responses of the tandem cable models could be completely suppressed when both were controlled using passive-suction-jet pipes.

scholarly journals Numerical simulation of temperature induced structural static responses for long-span suspension bridge

2017 ◽  
Vol 210 ◽  
pp. 246-252
Author(s):  
Lan Chen ◽  
Jingliang Deng ◽  
Linren Zhou ◽  
Yong Xia
Keyword(s):  
Numerical Simulation ◽  
Suspension Bridge ◽  
Long Span ◽  
Static Responses

Numerical Simulation of a Multistage Radial Inflow Turbine

2006 ◽  
Author(s):  
Yijin Li ◽  
Qun Zheng
Keyword(s):  
Numerical Simulation ◽  
Flow Fields ◽  
Flow Patterns ◽  
Secondary Flows ◽  
Radial Turbine ◽  
Aerodynamic Performances ◽  
Radial Inflow Turbine ◽  
Turbine Impeller

Aerodynamic performances of a three–stage radial inflow turbine are investigated with numerical simulation. Detailed flow fields, flow patterns, such as secondary flows etc. in the radial turbine impeller are presented and discussed in this paper.

Flutter Analysis of Long-Span Suspension Bridges Considering Yaw Wind and Aerostatic Effects

2021 ◽  
Author(s):  
Xin-Jun Zhang ◽  
Fu-Bin Ying ◽  
Lei-Lei Sun
Keyword(s):  
Wind Speed ◽  
Aerodynamic Force ◽  
Coupling Effect ◽  
Suspension Bridge ◽  
Computational Procedure ◽  
Wind Effect ◽  
Suspension Bridges ◽  
Long Span ◽  
Flutter Analysis ◽  
Yaw Angle

Based on the aerostatic and self-excited aerodynamic force models, a computational approach of three-dimensional (3D) refined flutter analysis for long-span bridges under skew winds is established, in which the structural nonlinearity, aerostatic effect and full-mode coupling effect, etc., are fully considered, and the computational procedure ([Formula: see text] flutter-sw) is developed accordingly. By taking the Runyang Suspension Bridge over the Yangtze river as an example, under the wind attack with initial angles of 0∘ and [Formula: see text] and yaw angles between 0∘ and 25∘, the flutter stability of the bridge in completion under skew winds is analyzed, and the influences of skew wind and aerostatic effect on the flutter stability of suspension bridges are assessed. The results show that the aerostatic effect has a significant influence on the flutter stability of long-span suspension bridge, and it may worsen its flutter stability, with an average decrease of 6.0%. However, it does not change the evolution of flutter stability of suspension bridge with increasing wind yaw angle. The critical flutter wind speed fluctuates with the increase of wind yaw angle, and it reaches the lowest value mostly under the skew wind, with an average reduction of 8.0%. The combined influence of the aerostatic effect and skew wind further reduces the flutter critical wind speed by 11.5% on average, and therefore, the aerostatic effect, skew wind effect and their adverse influences need to be comprehensively considered in the flutter analysis of long-span suspension bridges.

Control of Vibrations due to Moving Loads on Suspension Bridges

2006 ◽  
Vol 11 (3) ◽  
pp. 293-318 ◽  
Author(s):  
M. Zribi ◽  
N. B. Almutairi ◽  
M. Abdel-Rohman
Keyword(s):  
Bridge Deck ◽  
Suspension Bridge ◽  
Lyapunov Theory ◽  
Dynamic Responses ◽  
Suspension Bridges ◽  
Control Force ◽  
Moving Loads ◽  
Hydraulic Actuator ◽  
Long Span ◽  
Suspended Cables

The flexibility and low damping of the long span suspended cables in suspension bridges makes them prone to vibrations due to wind and moving loads which affect the dynamic responses of the suspended cables and the bridge deck. This paper investigates the control of vibrations of a suspension bridge due to a vertical load moving on the bridge deck with a constant speed. A vertical cable between the bridge deck and the suspended cables is used to install a hydraulic actuator able to generate an active control force on the bridge deck. Two control schemes are proposed to generate the control force needed to reduce the vertical vibrations in the suspended cables and in the bridge deck. The proposed controllers, whose design is based on Lyapunov theory, guarantee the asymptotic stability of the system. The MATLAB software is used to simulate the performance of the controlled system. The simulation results indicate that the proposed controllers work well. In addition, the performance of the system with the proposed controllers is compared to the performance of the system controlled with a velocity feedback controller.

Sign in / Sign up

Export Citation Format

Share Document