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Frontiers of Mechanical Engineering

ISSN 2095-0233

ISSN 2095-0241(Online)

CN 11-5984/TH

邮发代号 80-975

2019 Impact Factor: 2.448

Frontiers of Mechanical Engineering  2024, Vol. 19 Issue (2): 10   https://doi.org/10.1007/s11465-024-0781-7
  本期目录
Reduced-order modeling and vibration transfer analysis of a fluid-delivering branch pipeline that consider fluid–solid interactions
Wenhao JI1,2, Hongwei MA1,2, Wei SUN1,2(), Yinhang CAO3
1. School of Mechanical Engineering and Automation, Northeastern University, Shenyang 110819, China
2. Key Laboratory of Vibration and Control of Aero-Propulsion Systems (Ministry of Education), Northeastern University, Shenyang 110819, China
3. College of Power and Energy Engineering, Harbin Engineering University, Harbin 150001, China
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Abstract

The efficient dynamic modeling and vibration transfer analysis of a fluid-delivering branch pipeline (FDBP) are essential for analyzing vibration coupling effects and implementing vibration reduction optimization. Therefore, this study proposes a reduced-order dynamic modeling method suitable for FDBPs and then analyzes the vibration transfer characteristics. For the modeling method, the finite element method and absorbing transfer matrix method (ATMM) are integrated, considering the fluid–structure coupling effect and fluid disturbances. The dual-domain dynamic substructure method is developed to perform the reduced-order modeling of FDBP, and ATMM is adopted to reduce the matrix order when solving fluid disturbances. Furthermore, the modeling method is validated by experiments on an H-shaped branch pipeline. Finally, transient and steady-state vibration transfer analyses of FDBP are performed, and the effects of branch locations on natural characteristics and vibration transfer behavior are analyzed. Results show that transient vibration transfer represents the transfer and conversion of the kinematic, strain, and damping energies, while steady-state vibration transfer characteristics are related to the vibration mode. In addition, multiple-order mode exchanges are triggered when branch locations vary in frequency-shift regions, and the mode-exchange regions are also the transformation ones for vibration transfer patterns.

Key wordsfluid-delivering branch pipeline    vibration transfer analysis    reduced-order modeling    fluid–solid interactions    finite element method    absorbing transfer matrix method
收稿日期: 2023-11-01      出版日期: 2024-06-05
Corresponding Author(s): Wei SUN   
 引用本文:   
. [J]. Frontiers of Mechanical Engineering, 2024, 19(2): 10.
Wenhao JI, Hongwei MA, Wei SUN, Yinhang CAO. Reduced-order modeling and vibration transfer analysis of a fluid-delivering branch pipeline that consider fluid–solid interactions. Front. Mech. Eng., 2024, 19(2): 10.
 链接本文:  
https://academic.hep.com.cn/fme/CN/10.1007/s11465-024-0781-7
https://academic.hep.com.cn/fme/CN/Y2024/V19/I2/10
Fig.1  
Fig.2  
Fig.3  
Fig.4  
Fig.5  
Domain Density/(kg·m−3) Elastic modulus/Pa Poisson’s ratio Velocity/(m·s−1) Pressure/Pa
Solid 7800 2.04× 1011 0.285 ? ?
Fluid (air) 1.293 ? ? 0 0
Fluid (water) 1000 ? ? 0 0
Tab.1  
Fig.6  
Fig.7  
Order Frequency of the air-filled pipeline Frequency of the water-filled pipeline
Test/Hz ATMM/Hz FEM/Hz e1/% e2/% Test/Hz ATMM/Hz FEM/Hz e1/% e2/%
1 113.36 119.50 116.40 5.4 2.7 91.74 97.00 95.30 5.7 3.6
2 162.76 165.50 172.60 1.7 6.0 134.76 135.00 143.70 0.2 6.6
3 259.60 270.00 264.00 4.0 1.7 231.89 236.50 232.20 2.0 0.1
4 391.96 389.00 380.90 0.8 2.8 351.14 342.00 336.30 2.6 4.2
5 466.70 487.50 479.90 4.5 2.8 409.14 415.00 422.60 1.4 3.3
6 490.72 517.50 521.90 5.5 6.3 433.39 427.00 440.50 1.5 1.6
7 651.99 683.50 673.00 4.8 3.2 526.70 565.00 560.00 7.3 6.3
Tab.2  
Fig.8  
Fluid medium Stress response at point S1 Stress response at point S2
σt/MPa σs/MPa eσ=σt σsσt×100% σt/MPa σs/MPa eσ=σt σsσt×100%
Air 69.24 63.26 8.64 70.11 67.08 4.32
Water 64.32 63.55 1.20 76.12 68.52 9.98
Tab.3  
Fig.9  
Fig.10  
Fig.11  
Fig.12  
Fig.13  
Fig.14  
Fig.15  
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Fig.17  
Fig.18  
Fig.19  
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Fig.21  
Abbreviations
ATMM Absorbing transfer matrix method
CR Change rate
DOF Degree of freedom
FDBP Fluid-delivering branch pipeline
FEM Finite element method
FVAP Fluid velocity and pressure
ROM Reduced-order modeling
SAM Semi-analytical method
SIM Structural intensity method
TMM Transfer matrix method
Variables
Af Area of the fluid
A Transfer matrix between the master and slave branches
b Number of boundary DOFs
Cr, c Damping matrices of the structure and fluid, respectively
fx, fy, fz External forces at a position in the x, y, and z directions, respectively
f Natural frequency
Gc, G Constraint matrix and transformation matrix, respectively
i~ Number of internal DOFs
Ii(t) Structural intensity response
Kps, k, Kc, K Stiffness matrices of the pipeline, fluid, coupling element, and pipeline system, respectively
K^ Reduced stiffness matrix
M(n − 1) General transfer matrices used in TMM
Mps, m, M Mass matrices of the pipeline, fluid, and pipeline system, respectively
mx, my, mz External moments at a position in the x, y, and z directions, respectively
M^ Reduced mass matrix
Pf Fluid pressure
Q^ Reduced external force
Q^(L, s) Transfer matrix used in TMM
R^(L, s) External excitation vector used in TMM
| u˙¯| Amplitudes of the velocity responses
u˙, v˙, w˙ Velocity responses at a position in the x, y, and z directions, respectively
un Node displacement response
u˙~, σ~ Steady-state velocity and stress
Vf Fluid velocity
W˙k, W˙s, W˙d CRs of kinetic, strain, and damping energies, respectively
x Reduced DOFs
y( z^, t) Time-domain state vectors
Θ~s, Γ^s, Ψ^s, D^s Coefficient matrices used in TMM
ϕ ˙x, ϕ˙y, ϕ ˙z Angular velocity responses at a position in the x, y, and z directions, respectively
Φ^ Frequency-domain state vectors
|σ¯| Amplitudes of stress responses
σ Stress response
ψ, γ Phase angles of stress and velocity responses, respectively
ω Angular frequency
Ξ State matrix of the branch
ξ1, ξ2 First- and second-order damping ratios, respectively
  
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