28-39اسماء


Al-Khwarizmi Engineering Journal,Vol. 13, No. 1, P.P.  

 

Experimental and Numerical 

Asmaa Ali Hussein
Foundation of Techni

Email: 

(Received 4 September  
https://doi.org/10.22153/kej.2017.01.001

Abstract 
 
All central air conditioning systems contain piping system with various components, sizes, material, and layouts. If 

such systems in operating mode, the flow in piping system and its component such as 
vibration due to some flow phenomenon’s. In
used to study the flow-induced vibration in valves. Computational fluid dynamics (CFD) concepts are included with 
one-way and two-way fluid-structure interaction concepts by using finite element software Package (ANSYS 14.57).
Detection analysis is performed on flow characteristics under operation conditions
vibration. Most of real geometrical, operational, and boundary conditions are simulated to obtain best similarity with 
real operation conditions. Comparisons performed between experimental data and numerical results (one
way simulation) to verify the results. The main
vibration for valve is the water pulsation in addition to amount of water hammering
water pulsation in globe valve is the vortex shedding and pressure differe
valve. The vibration amplitude was increased with increasing flow rate
30% and then decreased until flow rate reaches to around 85% and then trends to be constant. 
 
Keywords: Flow-induced vibration, vortex shedding, pressure pulsation, v
transform (FFT). 
 
  
1. Introduction 
 

The vibration in piping system and its 
component especially valves can occurs due to 
many reasons. Some of these reasons related to
unavoidable flow phenomenon such as turbulence
cavitation, vortex shedding, and pressure 
pulsation. The other reasons related to structural 
behavior such as the resonance between the long 
pipeline and the other vibrating equipment such as 
pumps. The high level of vibration in piping 
system can cause breakdowns because the
noise, fracture, and fatigue failure. The reduction 
of vibration level in such systems is a valuable
task to avoid breakdown. The reduction 
vibration requires a wide knowledge of vibration 
source, causes, types, and how can to eliminate or 
reduce the causes. The prior investigation of flow 

  

Khwarizmi Engineering Journal,Vol. 13, No. 1, P.P. 28- 39 (2017)
 

Experimental and Numerical Research on Flow-Induced Vibratio
Valves 

 
Asmaa Ali Hussein 

Foundation of Technical Education/ Baghdad- Iraq 
Email: asmaa31930@yahoo.com 

 
September 2016; accepted 3 January 2017)

https://doi.org/10.22153/kej.2017.01.001 
 
  

All central air conditioning systems contain piping system with various components, sizes, material, and layouts. If 
the flow in piping system and its component such as valves can produce severe 

In this research, experimental measurements and numerical simulation are 
induced vibration in valves. Computational fluid dynamics (CFD) concepts are included with 

structure interaction concepts by using finite element software Package (ANSYS 14.57).
on flow characteristics under operation conditions and relations with structural 

geometrical, operational, and boundary conditions are simulated to obtain best similarity with 
performed between experimental data and numerical results (one

way simulation) to verify the results. The main conclusion was drawn from the study that the dominant source of 
vibration for valve is the water pulsation in addition to amount of water hammering. In addition, the main source of 
water pulsation in globe valve is the vortex shedding and pressure difference between upstream and downstream of 

with increasing flow rate until to be maximum when the flow rate around 
30% and then decreased until flow rate reaches to around 85% and then trends to be constant.  

vortex shedding, pressure pulsation, valve, finite element, ANSYS

The vibration in piping system and its 
component especially valves can occurs due to 

reasons related to 
such as turbulence, 

avitation, vortex shedding, and pressure 
related to structural 

the resonance between the long 
pipeline and the other vibrating equipment such as 

high level of vibration in piping 
because the leaks, 

reduction 
systems is a valuable 

The reduction of 
a wide knowledge of vibration 

to eliminate or 
ation of flow 

behavior and flow-induced vibration of such 
system will give a most important knowledge for 
optimum anti vibration design. The valve is one of
the main components of any piping system.
behavior of flow inside the valve and 
between the flow and valve structure components 
can be the source of severe vibration
Fletcher [1] introduced a theoretical
oscillations of piping fittings
conclusion from this study is t
typical ranges of acoustic resistance
is possible. The analysis process t
oscillations of little amplitude. Lighterink
[2] presented a paper described
examine the loads on tools due to the 
vibrations. Investigations performed on a piping 
system with standard equipment to investigate: a) 
the vibrational natural mode shape of the piping, 

 

    
Al-Khwarizmi 
  Engineering  

Journal 

Induced Vibration in 

All central air conditioning systems contain piping system with various components, sizes, material, and layouts. If 
valves can produce severe 

research, experimental measurements and numerical simulation are 
induced vibration in valves. Computational fluid dynamics (CFD) concepts are included with 

structure interaction concepts by using finite element software Package (ANSYS 14.57). 
and relations with structural 

geometrical, operational, and boundary conditions are simulated to obtain best similarity with 
performed between experimental data and numerical results (one-way and two-

that the dominant source of 
In addition, the main source of 

nce between upstream and downstream of 
to be maximum when the flow rate around 

ANSYS, fast Fourier 

induced vibration of such 
a most important knowledge for 

The valve is one of 
of any piping system. The 

behavior of flow inside the valve and interaction 
between the flow and valve structure components 

the source of severe vibration. N. H. 
theoretical study on the 

piping fittings. The main 
that there exist 

resistance for oscillation 
the formation of 

. Lighterink et. al 
] presented a paper described a method to 

due to the mechanical 
performed on a piping 

to investigate: a) 
the vibrational natural mode shape of the piping, 

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 29 
 

b) the natural mode shapes of the piping and 
equipment, and c) the total loads on the 
equipment. Ravi Pankhania et. Al [3] carried out 
study on vibration of piping equipment for nuclear 
application. The study included design and 
analysis of motor operated flow control used for 
nuclear application. Malik I. Al- Amayreh et.al [4] 
presented a research on butterfly valve for 
vibration reduction. The work included numerical 
simulation of a butterfly valve used to control the 
flow rate in industrial process. Present research 
includes experimental and numerical investigation 
on flow-induced vibration in globe valve. 

 
 

2. Numerical Simulation 
 
Computation fluid dynamics (CFD) with the 

aid of finite element software package (ANSYS 
14.57)is used in the current study. This program 
analyzes and solves a wide range of different 
mechanical problems, such as the structural, fluid 
flow, thermal, and the fluid-structure interaction 
problems [5]. ANSYS mechanical (APDL 
14.57)is used for structural analysis and ANSYS 
(Fluent 14.57) is used for fluid analysis and 
ANSYS workbench is used for fluid-structure 
interaction analysis. CFDisused to investigate the 
flow characteristics for the vicinity of valve. The 
flow characteristics included pressure and velocity 
distribution, velocity vector, vortex, cavitation 
regions, and the integrated dynamic forces on the 
structure. FSI applications involve coupling of 
fluid dynamics and structure mechanics 
disciplines: 1) Fluid flow exerts hydrodynamic 
forces on a structure and deforms and/or translates 
the structure. 2) Deformed or translated structure 
impart displacement to the fluid domain and 
changes its shape and thus changes the fluid flow. 
There are two modes of FSI. One-way solution 
used with conditions of very small of 
deformations in the structure. The solver 
calculates and passes flow fields from CFD to the 
structural analysis and no need to update and 
recalculate flow. Two-way is used when Large 
structural deformations is included where iterate 
between fluid solution and structural solution until 
the convergence is obtained. Both 1-way and 2-
way fluid-structure simulation are used in current 
research. The coupling of two- way solution is 
shown in Figure (1) [6].The aims of using the two 
simulations is to establish the accurate and best 
simulation for the problem and specify which 
mode of FSI give results close to experimental 

results. The numerical simulation will give good 
visualization of flow behavior inside the valves. 
Numerical simulation setup requires choosing the 
perfect geometry representation, suitable element 
type, boundary conditions, and material 
properties.  

 
2.1.  Element Type 

 
Two types of element used in current research. 

For structural analysis, SHELL281is used. The 
element has eight nodes with six degrees of 
freedom at each node. For fluid analysis, higher 
order tetrahedral element (10 node) with hanging 
nodes is used. Figure (2) shows the elements type. 
  
2.2. Boundary Condition  

 
For structural analysis, clamped boundary (all 

degrees of freedom = 0) used at the beginning and 
the end of valves to simulate the flanged 
connection of valves with piping system. For fluid 
analysis, velocity inlet boundary (V= 1m/s) used 
at the inlet of valve and wall boundary(V = 0) 
used to bound fluid and solid contact. 

 
2.3. Material Properties 

 
The fluid used as flow material is water at 

average temperature 15 ̊c. The standard values of 
density and viscosity of water at this temperature 
used in numerical simulation. The material of 
valve body is cast iron. The standard values of 
mechanical properties (density, modulus of 
elasticity, and poissons ratio) according to ASTM 
for cast iron are used in structural analysis.  

 
2.4. Simulation Setup 
     

The one-way simulation included the transient 
fluid flow solution for time history of pressure 
distribution and then export the pressure solution 
at each time step to transient structural solution to 
obtain the time history of vibrational 
displacement. The solution results data obtained 
and then plotted with the aid of suitable graphic 
program. The two-way simulation included 
coupling solution of flow and structural solution 
to obtain the vibrational displacement directly. 
The fundamental steps associated with the 
application of the finite element method to solve 
problems in fluid simulation showed in the 
diagram in figure (1) [7]. 

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Asmaa Ali Hussein                         Al-Khwarizmi Engineering Journal, Vol. 13, No. 2, P.P. 28- 39 (2017) 
 

 30 
 

 
 

Fig. 1. Coupling procedure and numerical simulation steps. 
 

 

 
 

Fig. 2. Element type. 
 
 

3. Theoretical background 
3.1.  Flow analysis 
 

When dealing with water flows, some 
assumptions included: 
1- Three dimensional flow,  2-Incompressible 
flow,  3-Newtonian fluid.  
The governing equations of flow can be 
summarized by [8]: 
(i) Mass conservation (continuity equation)   
Equating the quantity of mass entering and 
leaving an element volume is:  

0=
∂
∂

+
∂
∂

+
∂
∂

z
w

y
v

x
u

                                        ... (1) 

Where: 
x, y, and z are the Cartesian coordinates. 
u, v,  and w are the velocity component in 
direction of x, y, and z respectively [m/s].   
(ii) Momentum conservation (Navier–Stokes 
Equations) 
Momentum conservation equation is: 
- in x- direction : 

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 31 
 

)(

)(

2

2

2

2

2

2

z
u

y
u

x
u

g
z
u

w
y
u

v
x
u

u
x
P

x

∂
∂

+
∂
∂

+
∂
∂

+=
∂
∂

+
∂
∂

+
∂
∂

+
∂
∂

m

rr

           ... (2) 

-in y- direction : 

)(

)(

2

2

2

2

2

2

z
v

y
v

x
v

g
z
v

w
y
v

v
x
v

u
y
P

y

∂
∂

+
∂
∂

+
∂
∂

+=
∂
∂

+
∂
∂

+
∂
∂

+
∂
∂

m

rr

             ... (3) 

- in z- direction : 

)(

)(

2

2

2

2

2

2

z
w

y
w

x
w

g
z
w

w
y
w

v
x
w

u
z
P

z

∂
∂

+
∂
∂

+
∂
∂

+=
∂
∂

+
∂
∂

+
∂
∂

+
∂
∂

m

rr

         … (4) 

Where: 
P: pressure (N/m2) 
ρ: fluid density (kg/m3) 
g: gravitational acceleration (m/s2) 
μ: Viscosity (N.s/m2) 
The comprehensive formulation of above 
equations in finite element analysis detailed in 
reference [9]. 
 
3.2. Structural Analysis 
 

The vibration responses of any continous 
structure due to external load can be evaluated by 
using numerical technique to solve the equation of 
motionwhich can be written as [9]. [�]�̈̅ +  [�]�̇̅ +  [�]�̅ =  ��(�)                           ...(5) �̈̅ = [�]�� (��(�) − [�]�̅ − [�]� �̇  )               …(6) 
Where: 
[M]: Mass matrix [kg] 
[c]: damping coeficient matrix [kg/s] 
[k]: stifness matrix [kg/s2] �, �,̇ �̈: displacement, velocity andacceleration of 
structural particle respectively.  
The complete procedure of numerical solution for 
above structural equations presented in reference 
[9]. 
 

4. Experimental Work 
 

Experimental work included vibration 
measurements for piping system components. The 
experimental tests performed on the piping of 
central air conditioning system in university of 
Baghdad because this system suffers severe 
mechanical vibration. The piping system contains 
many components such as valves, strainers, 
elbows, tees, and flow meters. The flow rate 
inside the system can be controlled with the aid of 
pumps and valves. The vibration measuring 
system can be used for this purpose. This system 
included three-axis accelero meter which can be 
mounted on any position in piping system to 
measure the dynamic acceleration of vibrational 
structure. Then, the output acceleration signal 
goes to Analog to digital convertor (ADC) card 
and then showed and recorded by using suitable 
computer software. Figure (3)shows the flow of 
vibration signal and apparatus of vibration signal 
measurements used in the current research. The 
accelerometer attached rigidly to the structure to 
measure the acceleration at any point in the 
structure in the form of signal. The more details 
and calibration of the vibration measuring devices 
performed and detailed in reference [10]. 

 
 

5. Description of Piping System 
 

All experimental tests performed on the piping 
network of central air conditioning system of the 
central library in university of Baghdad. The 
network consists of pipes with different diameters, 
lengths, and thickness. Also, there are many types 
of valves such as gate valve, balance valve, globe 
valve, and check valve. The vibration 
measurements performed on globe valve of piping 
network. 

 

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Asmaa Ali Hussein                         Al-Khwarizmi Engineering Journal, Vol. 13, No. 2, P.P. 28- 39 (2017) 
 

 32 
 

 
 
Fig. 3. Flow diagram of vibration signal and 
vibration measurement devices. 
 
 
6. Analysis Procedure  
 

The most important task is to establish a 
feasible, precise, and logical analysis for the 
obtained experimental and numerical data. Precise 
analysis will lead to precise results and 
conclusions. In the current research, specific 
procedureis used to analyze the obtained data. 
This procedure consists of the following steps: 
1. Obtain the experimental data from vibration 

measurement tests for globe valve. The 
vibration dataplotted in both time domain and 
frequency domain. 

2. Make suitable and precise numerical 
simulation for the flow inside the valve, which 
examined experimentally at step 1 

3. From the numerical simulation of step 2, the 
response of piping system to flow excitation 
which is the time history of structure 
displacement (vibration) due to flow dynamic 
forces can be obtained. These structure 
displacements (vibration) obtained from both 
1-way and 2-way numerical simulations.  

4. Make a precise correlation between the 
numerical results of structure vibration and 
flow characteristics to find the real reasons of 
structure vibration. 

5. Make precise comparisons between the results 
of structure vibration obtained from 
experimental tests and numerical simulations. 

6. Make feasible and precise correlation between 
the experimental results of structure vibration 
and flow characteristics obtained from 
numerical simulations 

7. Establish the conclusions. 
  
 
7. Results and Discussions 
 

The schematic diagram of the components of 
globe valve is shown in the figure (4). It mainly 
consists of two important regions: flow domain 
which the space occupied by fluid and contains all 
flow phenomenon's which the main cause of 
dynamic fluid forces and the pipe wall which 
represents the structure domain whose vibration is 
to be measured. 

 

 
 

Fig. 4. Schematic diagram of globe valve. 
 
 

The geometry of the flow domain is an 
important parameter for initiation and formation 
of the flow phenomenon. Figure 5 shows the 
meshed flow domain for numerical simulation at 
different enclosure ratio.  

 
 
 
 
 
 
 
 
 

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Asmaa Ali Hussein                         Al-Khwarizmi Engineering Journal, Vol. 13, No. 2, P.P. 28- 39 (2017) 
 

 33 
 

 

 
 

Fig. 5. Flow domain at different enclosure ratio. 
 

 
Figures6 and 7 show the velocity distribution 

and pressure distribution obtained from numerical 
simulation. The distribution of pressure and 
velocity over the flow domain depends mainly on 
amount of enclosure of the valve. Figure6 shows 

the pressure distribution at enclosure 100%, 80% 
and 60% respectively while figure 7shows the 
velocity distribution for the same enclosure ratio 
respectively. The entrance flow velocity is 1m/s. 

 

 
 

Fig. 6. Pressure distribution over the flow domain of globe valve at different enclosure ratio. 

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Asmaa Ali Hussein                         Al-Khwarizmi Engineering Journal, Vol. 13, No. 2, P.P. 28- 39 (2017) 
 

 34 
 

 
 

Fig. 7. Velocity vector distribution over the flow domain of globe valve at different enclosure ratio. 
 

 
Figure 8and 9 show the dynamic response 

(vibration) on the valve wall obtained from 1-way 
and 2-way numerical solution respectively in both 
time and frequency spectrum (FFT). These results 
obtained from numerical simulation as a table of 
time history of wall displacement and then drawn 

by using graphic program.Figure10shows the 
experimental vibration measurement for the same 
valve with enclosure of 30%obtained by 
experimental test in both time and frequency 
spectrum (FFT). 

 

 
 

Fig. 8. Displacement of globe valve obtained from numerical solution 1-way.  

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 35 
 

 
 

Fig. 9. Displacement of globe valve obtained from numerical solution 2-way.  
 

 
 

Fig. 10. Time domain and frequency spectrum (FFT) of experimental vibration signal of globe valve. 
 
 

It is obvious that the vibration measurements 
will determine the frequency spectrum and the 
amplitude of vibration but does notsupply details 
about the source of shaking because the absolute 
value of vibration does not give a suitable 
knowledge about the flow behavior and vibration 
source inside the piping system. The first 
observation on the vibration data is that the 
behavior of experimental measured vibration 
signal is close to that obtained from 1-way 
numerical simulation than that obtained from 2-
way numerical simulation. Experimental tests 
show that the vibration signal was repeated with 
approximately constant frequency (336Hz)and 
amplitude (0.4mm)and there is one distinguish 
peak in frequency spectrum. Similarly, the 1-way 
simulation provides repeated vibration signal with 
some noise and frequency spectrum shows one 

distinguish peak. The vibration signal obtained 
from 2-way simulation has remarkable decay in 
amplitude and changing frequency until 
approaches to convergence state. In addition, the 
frequency spectrum shows more than one 
distinguish peak (300Hz). This is an important 
observation because it confirms the validity of 
numerical simulation. The 2-way numerical 
simulation is an important issue when the 
structure undergoing large deflection vibration. 
This observation indicates that 1-way FSI 
simulation is sufficient to estimate the dynamic 
response of piping structure in current study 
where the vibration of valve can be considered as 
small deflection vibration. Different operation 
conditions, support type, material size, types, and 
boundary conditions of the same structure may be 
made 1-way FSI simulation not sufficient to 

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Asmaa Ali Hussein                         Al-Khwarizmi Engineering Journal, Vol. 13, No. 2, P.P. 28- 39 (2017) 
 

 36 
 

predict the dynamic response (vibration). The 
second and most important observation on the 
vibration results that the response of valve to flow 
excitation is approximately repeated with amount 
of noise in the form of random vibration. This 
indicates that the dominant source of vibration can 
be water pulsation or water hammering or vortex 
shedding because all these sources provide a 
regular excitation wave. Water pulsation and 
water hammering are including pressure waves. 
Water pulsation included steady oscillation with 
small amplitude. This small amplitude can be 
developed and enlarge if the resonance conditions 
are realize while the water hammering is unsteady 
transient oscillations with large amplitude. The 
water hammering may occured in valves and 
pumps but it is related to fluid –structure 
interaction. The comparisons between the 
experimental vibration data and the numerical 
simulation results show that no significant FSI 
was established for current case study. This 
observation proves that the dominant source of 
vibration for valve is the water pulsation in 
addition to amount of water hammering. Now, it 
is a valuable to specify the source of water 
pulsation for flow in valves. By return to figures 6 
and 7, the main source of water pulsation is the 
vortex shedding and pressure difference between 

upstream and downstream of valve. Figure 7 
shows many circulation regions which can be the 
source of vortex. The vortex shedding is a regular 
flow phenomenon can cause regular pressure 
wave which in turn excite the structure to vibrate. 
Figure 6 shows high reduction of pressure cross 
the valve section. The pressure reduction causes 
the high amount of turbulence energy transferred 
into the system and can be the source of 
associated random vibration (noise).In addition, 
the appearance of one distinguish peak in 
frequency spectrum for both experimental and 1-
way numerical simulation proves that the system 
may vibrates close to one natural mode of 
vibration. This phenomenon called lock-in where 
the frequency of vortex shedding coincides with 
one of the natural frequencies of the system. The 
other subsequent result from vibration data and 
flow characteristics that the vibration of valve 
depends on the flow path and the flow rate of 
water sincethe flow characteristics (velocity and 
pressure)distribution has strong dependency on 
the amount of valve enclosure (flow path) as 
shown in figures 6-7. Figure 11 shows the 
vibration measurement data (displacement signal) 
of globe valve measured at different flow rate 
cross the valve (enclosing percentage).  

 

 
 

Fig. 11. Displacement measurement of globe valve at different flow rate cross the valve. 
 
 

It is obvious from the figure that the vibration 
amplitude increases with increasing of flow rate to 
be maximum when the flow rate around 30% and 

then decreased until flow rate reaches to around 
85% and the trends to be constant as shown in 
figure 12. 

 

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Asmaa Ali Hussein                         Al-Khwarizmi Engineering Journal, Vol. 13, No. 2, P.P. 28- 39 (2017) 
 

 37 
 

 
 

Fig. 12.Vibration amplitude of globe valve versus 
flow rate cross the valve. [Experimental data]. 
 

 
This behavior of vibration is related to flow 

characteristics as mentioned. Figure 7 shows that 
severe flow conditions (high pulsation and vortex 
shedding) between enclosure percentages 80-60% 
[flow rate 20-40%]. This confirms the previous 
results. The dependency of vibration level on flow 
characteristics (flow phenomenon's, flow path, 
flow rate, pressure distribution, and velocity 
distribution) requires other experimental and 
numerical analysis on valve of different geometry. 

 
 

7. Conclusion 
 
1. Experimental tests show that the structural 

vibration signal was approximately repeated 
with approximately constant frequency 
(336Hz) and amplitude with little noise 
signals. This can be shown from FFT of 
experimental data where one distinguish peak 
represent the dominant vibration frequency and 
many small peaks represent the noise.  

2. There is one distinguish peak in frequency 
spectrum for experimental vibration 
measurement. 

3. The behavior of experimental measured 
vibration signal of valve is close to that 
obtained from 1-way numerical simulation 
than that obtained from 2-way numerical 
simulation. Therefore, the 1-way FSI 
simulation is sufficient to estimate the dynamic 
response (vibration) of valve because it can be 
considered as small deflection vibration. 

4. The dominant source of vibration of valves can 
be water pulsation or water hammering or 
vortex shedding because all these sources 
provide a regular excitation wave with 

approximately constant frequency at steady 
state of velocity and pressure. 

5. The dominant source of vibration for globe 
valve established in current study is the water 
pulsation in addition to amount of water 
hammering 

6. The main source of water pulsation in globe 
valve is the vortex shedding and pressure 
difference between upstream and downstream 
of valve. 

7. The vibration of valve dependent on the flow 
path and the flow rate of water since the flow 
characteristics (velocity and pressure) 
distribution has strong dependency on the 
amount of valve enclosure (flow path) 

8. The vibration amplitude increases with 
increasing of flow rate to be maximum when 
the flow rate around 30% and then decreased 
until flow rate reaches to around 85% and then 
trends to be constant 

 
 
Nomenclature 
 

 
 
8. References 
 
[1] N. H. Fletcher, "Autonomous vibration of 

simple pressure-controlled valves in gas 
flows", J. Acoustic. Soc. Am. 93(4), Pt. 1, 
April 1993. 

[2] N.E. LIGTERINK, R. DE GROOT, H.J. SLOT 
, EMAD GHARAIBAH, "Flow induced 
vibration of subsea gas production systems 
caused by choke valves", SPE Annual 
Technical Conference and Exhibition held on 
8-10 October 2012, San Antonio, Texas. 
Copyright 2012, Society of Petroleum 
Engineers. 

Description Symbol 
Cartesian coordinates. x, y, and z 
Velocity component in direction of x, 
y, and z respectively. u, v, and w 

Pressure (N/m2) P 
Fluid density (kg/m3) ρ 
Gravitational acceleration (m/s2) g 
Viscosity (N.s/m2) μ 
Mass matrix [kg] [M] 
Damping coefficient matrix [kg/s] [c] 
Stiffness matrix [kg/s2] [k] 
Displacement, velocity and 
acceleration of structural particle 
respectively. 

� , �̇ , �̈ :  

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 38 
 

[3] Ravi Pankhania, Dhaval Patel and V.M. 
Bhojawala, "Free Vibration Analysis of a 
Motor Operated Gate Valve for Nuclear 
Application Using Finite Element Analysis", 
International Journal of Advanced Mechanical 
Engineering. ISSN 2250-3234 Volume 4, 
Number 3 (2014), pp. 349-356. 

[4] Malik I. Al-Amayreh, Mohammad I. Kilani, 
Ahmed S. Al-Salaymeh, " Numerical Study of 
a Butterfly Valve for Vibration Analysis and 
Reduction" International Journal of 
Mechanical, Aerospace, Industrial, 
Mechatronic and Manufacturing Engineering 
Vol:8, No:12, 2014. 

[5] ANSYS theory reference. Twelve edition, 
2009, ANSYS Inc., South Point, Canonsburg, 

[6] H. H. Hamad, "Dynamic response of solar 
collector for self-cleaning", Ph.D thesis, 
university of technology, 2012. 

[7] C. Taylor and T. G. Hughes, ˝Finite Element 
Programming of the Navier-Stokes Equations”, 
Bell and Bain Ltd., 1st Published, 1981. 

[8] Sinan A. Ali “ Study effect of Riblet Upstream 
Wing-Wall junction Numerically and 
Experimentally” ,M.Sc. thesis, Mechanical 
eng. Dept. University of Technology, 2011. 

[9] Friedel Hartmann Casimir Katz “Structural 
Analysis with Finite Elements” Springer-
Verlag Berlin Heidelberg 2007. 

[10] Ihsan.A. Baqer, "Modeling of 3D Grasping 
of artificial hand under dynamic load", Ph.D 
thesis, University of technology, Baghdad, 
2014. 

 
 
 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
 
 
 
 

  
  
  
  
  
  
  

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 )2017( 28-39 صفحة ،2العدد ،13المجلد الھندسیة الخوارزمي جلةم             اسماء علي حسن                                                   

 39 
 

  
 

  على االھتزاز الناتج عن الجریان في الصمامات بحث عملي وعددي
  

  علي حسین أسماء
  العراق_ بغداد/ ھیئة التعلیم التقني

  asmaa31930@yahoo.com:البرید االلكتروني

  
  

  الخالصة
  

عندما تكون ھذه االنظمة في حالة . تحتوي على منظومة انابیب مع ملحقات وقیاسات ومواد ومخططات متنوعةجمیعھا تكییف الھواء المركزیة  أنظمةإن 
تم اجراء ، في البحث الحالي. بسبب بعض ظواھر الجریان اً حاد اً تشغیل فان الجریان في منظومة االنابیب وملحقاتھا مثل الصمامات یمكن ان ینتج اھتزاز

تم استخدام مفھوم دینامیك الموائع العددي ومفھوم التفاعل بین المائع . عملیة والمحاكاة العددیة لدراسة االھتزاز الناتج عن الجریان في الصماماتالالقیاسات 
تم اجراء تحلیل تنبؤي على خصائص ).  ANSYS 14.57(د طریقة العناصر المحددة والھیكل باتجاه واحد وباتجاھین باستخدام برنامج حاسوبي یعتم

. تم محاكاة اغلب الظروف الھندسیة والحدیة للحصول على افضل تشابھ مع الظروف الحقیقیة. الجریان تحت ظروف التشغیل والعالقة مع اھتزاز الھیكل
اھم النتائج . اسات العملیة والمحاكاة العددیة للتحقق من النتائج والحصول على نتائج دقیقةتم اجراء مقارنات بین النتائج المستحصلة من القیوكذلك 

المصدر الرئیس لنبضات الماء في  كذلك ان . طرق الماء فضال عنلالھتزاز داخل الصمامات ھو نبضات الماء  المستخلصة من الدراسة ان المصدر الرئیس
ایضا وجد ان سعة االھتزاز تزداد بازدیاد معدل الجریان لتصل الى . الخروج للصماموق الضغط بین مجرى الدخول الصمام الكروي ھو انبثاق الدوامات وفر

 .  ومن ثم تبقى ثابتة تقریبا% ٨٠ومن ثم تنخفض الى ان یصل معدل الجریان حوال % ٣٠اعلى قیمة عند حوالي معدل جریان 
  

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