Bird strike Analysis on Aircraft structure using SPH Model · 2020. 7. 30. · Bird strike Analysis...

Bird strike Analysis on Aircraft structure using SPH Model M.Dakshina Moorthy

1, T.Chakravarthi

2,

1Department of Mechanical Engineering, VANI1, chevutur

Email: [email protected] 21

Department of Mechanical Engineering, VANI1, chevutur

Email: mailto:[email protected]

Abstract: As a result of aerial vehicles collisions

with birds in the air, there are many accidents that

cause high cost and sometimes losing of life. In the

aviation sector, bird impact is considered an

important problem that causes material damage and

threatens flight safety. Bird-strikes on aircraft is a

major threat to human life and there is a need to

develop structures which have high resistance

towards these structures. It is imperative that today's

designed and manufactured aviation structures

comply with safe flight and landing requirements. In

order to satisfy these requirements, the behavior of

structural parts against bird impact is investigated.

In order to reduce the experimental costs, test is

studied on designing a leading edge by using the

finite element methods. In this study Smooth

Particle Hydrodynamics (SPH) and CEL (Coupled

Eulerian Lagrangian) was used for modeling the bird

Through the obtained results, it is aimed to improve

the design process and to produce more durable and

safe structures. But the high cost of testing and of

the "trial-and-error method" to increase the number

of tests, manufacturers are forced both time and

financially.

1.0 INTRODUCTION

Foreign material impact is a serious problem for

aircraft structures in general. Bird strike is one of

those, which causes significant loss of money and

human life. Because bird strike causes about 90%

percent of the aircraft accidents, people have been

trying to protect and strengthen aircrafts from bird

strike since early 1970s. Pilots may face from two to

five bird-strikes among their carrier since in-service

knowledge indicates that bird-strike occasions are

common incident in aviation. The first known bird

strike accident was recorded in 1908 in the Dayton /

Ohio / North Carolina region of the United States as

the murder of a bird by Orville Wright who is one of

the co-founders of the first plane which have a steam

engine. It can be given as an example of the accident

that there was no loss of life by forced landing in

Hudson River in New York city of United States of

America in January 2009, which was registered as

one of the biggest known accidents. The first bird

strike to a jet powered aircraft was in Germany in 27

August 1939. The first test flight of a jet powered

aircraft was on 24 August 1939. Three days later,

during the second flight, a loss of thrust was

experienced after a bird strike. Bird-strike events

postures significant threats to civilian and military

aircrafts as they lead to fatal to basic aircraft

components. Fuselage, engines, wings, windshield,

nose/radom are most common aircraft components

stricken by birds according to reports. Figure 1-1

shows those components of an aircraft that have a

risk of a bird-strike.

Fig. 1. Illustration of aircraft components

exposed to the risk of bird strike.

1.2 BIRD STRIKE PROBLEM

1.2.1 The Importance of Bird Strike in Aviation

As a result of the collision of an aircraft with foreign

objects, material and life-lost accidents occur. This

phenomenon, which is called as a foreign material

impact in the field of aviation, is examined in two

different sub-sections. One of these subsections,

solid body impact; a piece of metal that has fallen

from another aircraft or a stone which is on the

runway is often struck by the force of the wind on

the airstrip and hit by the aircraft. Another sub-title,

which is the subject of examination of this thesis at

the same time, is an accident that occurs when one

or more birds collide with aircrafts that may lead to

loss of human and bird life. The main difference

between these two collision states is that the solid

body reacts rigidly during the collision, while the

bird usually behaves in the direction of

fragmentation during bird collision. These two

behaviors have different effects on the structural

elements of the aerial vehicle. Bird strike is one of

the most important problems encountered in civilian

and military aviation areas. Guida (2008) stated that,

it is estimated that around 36,000 birds have been hit

every year worldwide. [12]

2 Literature Review

In this section, previous researches about bird strike

are carried out and necessary information related to

the subject of this research are given. Researches

about bird strikes has been started since 1970s and it

is still a current subject to work on.

Experimental equations are traditionally used to

analyze bird strike problems to determine the

thickness of structural components required to resist

bird strikes. However, the airworthiness

requirements have changed slightly and

experimental equations have not adequately met

today’s highly optimized complex aircraft

structures. Many researchers have focused on bird

strike research using computers and related

softwares in the last few decades.

Figure 2.1: Multi-material Bird Model

Airoldi and Cacchione (2006) evaluated the

numerical performances of bird models with

different material characterization and shapes using

Lagrangian approach. The approach has been

applied to analyse bird impacts in idealized

conditions considering the normal impact on a rigid

target. Lagrangian approach has been found suitable

to perform a large number of analyses focusing on

the impact loading parameters obtained by bird

models of different shapes and accepting different

material characterizations. [11]

In order to reduce the experimental costs, Guida

(2009) studied on designing a leading edge by using

the finite element methods. In this study Smooth

Particle Hydrodynamics (SPH) was used for

modeling the bird whereas a classical finite element

approach accepted. Greatly similar results between

the experimental test and the SPH bird numerical

model were obtained. Figure 3 shows the

comparison of the test and simulation. [13]

Figure 2.2: Numerical and Experimental Shape

after the Impact

Analyzing a novel rib-less tailplane of a C27J

aircraft is approved by an experimental bird-strike

test. Advanced numerical simulation techniques can

significantly help to design safer and more efficient

aircraft structures capable of withstanding a bird-

strike is shown by these results. [14] [15] [16]

Heimbs (2011) examined the effects of collisions at

high speeds on boom composite plots, along with

the phenomenon of bird hitting. Lagrangian and

Eulerian impactor models have been compared in

this study. [17] This comparision is given in Figure

4.

Figure 2.3: Bird strike simulation on composite

plate with the (a) Lagrangian and (b) Eulerian

impactor models

Ubels (2003) investigated several composite leading

edge designs for a bird strike and these designs are

based on a novel application of composite materials

with high energy-absorbing characteristics: the

tensor-skin concept. [18] Furthermore Reglero

(2010) examined bird impact events on aluminum

foam composite composite wing structures. [19]

Heimbs (2011) observed how composite leading

edge reacts to a bird strike using Abaqus/Explicit

finite element software. Bird strike on a rigid plate

analyses were performed firstly in order to validate

the bird model then this validated bird model was

used to analyse a bird strike on a composite wing

leading edge. It is appeared that final simulation

results correlate with the experimental data in this

study. [20]

3 SIMULATION OF BIRD STRIKE

3.1 Simulation Steps In this section, the steps for the analysis of a bird

strike that have to be followed is going to be

described. The analysis of bird strike can be divided

into four main parts. First, the problem should be

defined along with the aviation standards. In this

context, the impact location, bird shape and weight,

impact speed should be clearly assessed. Secondly,

the appropriate solution should be chosen. In

addition, required material model for the soft

impactor must be selected. Thirdly, material models

should be determined according to metallic and non-

metallic aircraft structures. Finally, the bird

simulation is going to be performed. Figure 3-1

shows the flowchart for suggested procedure of bird

strike analysis.

Figure 3-1: Flowchart for Bird Strike Analysis

Procedure

3.2 Problem Description and Modeling of Bird

Geometry

Dead bird or chicken corpses are used in the bird

strike certification tests. However, in the

experimental tests, various materials are used which

have specific geometric shapes reflecting a bird

body. Considering the variability of bird species and

the variations in the impact, the bird model must

have a certain degree of similarity to that used in

experimental tests.

Figure 3-2: Bird Strike Experiment Set-up

One of the most important parts of the bird impact

analysis is determining the appropriate bird model.

Model designation includes bird geometry and

material selection. There are certain geometric

shapes commonly used in bird geometry. These are

cylindrical, cylindrical hemispherical ends,

ellipsoidal and spherical shapes. In particular, the

cylindrical hemispherical ends and ellipsoidal

shaped bodies yielded closer results to the actual

bird body in the tests. Figure 3.2 shows the bird

model geometric shapes that Heimbs (2010)

indicated in his paper. [30]

Figure 3-3: Different Substitude Bird Impactor

Geometries

Federal Aviation Administration (FAA) have some

regulations for the bird strike test condition.

According to FAA’s Issue Paper G-1, bird strike test

condition is given by the parameters in Table 3-1.

Table 3-1: FAA Bird Strike Conditions

The bird strike requirement is specified as:

(a) The aircraft must be capable of continued safe

flight and landing during which likely structural

damage or system failure occurs as a result of –

(1) In airplane mode, impact with a 4-pound bird

when the velocity of the aircraft relative to the bird

along the aircraft’s flight path is equal to Vc at sea

level or 0.85Vc at 8,000 ft, whichever is more

critical;

(2) In VTOL/conversion mode, impact with a 2.2

pound bird at Vcon or VH (whichever is less) at

altitude up to 8,000ft.

(b) Compliance must be shown by tests or by

analysis based on tests carried out on sufficiently

representative structures of similar design.

where, VC is cruise speed and VH indicates the

hover speed.

3.3 Bird Model

The bird material has been replaced with an equal

mass of water, as birds mostly consists of water and

air trapped in the bones and lungs. The bird

geometry is represented as a cylinder with

hemispherical ends as this geometry resembles the

pressure time history of the real bird during the

impact tests as shown in Figure. The bird

characteristic such as diameter, cylinder length and

density are obtained by using empirical formulas.

A bird with mass equal to 2 pounds has been

considered in this analysis as per the certification

requirement.

Bird mass = 4 lb = 1.8 kg

Density = 960 kg/m3

Diameter = 0.077m

Total Length = Cylinder Length + Diameter =

0.225 m

Figure 3-4: Bird dimensions that is used in the

analysis

As birds, mostly composed of water, a water-like

hydrodynamic response has been considered as a

valid approximation for a constitutive model for bird

strike analyses. The Equation of state (EOS)

describes the pressure-volume relationship with

parameters of water at room temperature, hence the

Mie-Grüneisen EOS Us-Up approach in

Abaqus/Explicit was adopted for this purpose.

4. SOLUTION TECHNIQUES Selecting the method to be used in the analysis is

one of the most serious issues in the simulation of

the bird impact problem. In this section it will be

examined what the basic finite element solution

techniques used for non-rigid bodies during collision

simulation are. It will also show applicability to the

bird strike problem, taking into account the

advantages and disadvantages of the finite element

methods mentioned. There are basically four finite

element approaches that can be used in the

simulation of the bird impact problem. These

approaches are; Lagrangian Solution Technique,

Eulerian Solution Technique, Arbitrary

LagrangianEulerian Solution Technique (CEL) and

Smooth Particle Hydrodynamics Solution Technique

(SPH). The main difference between these

techniques is the solution networking approach.

4.1 CEL (Coupled Eulerian Lagrangian) Solution

Technique

In the classic Euler approach, the solution network

reflects a fixed area in space, and the area to be

computed should cover the area where the material

is likely to be found, except for the environment in

which the material is located. For this reason, the

classical Euler approach requires more computation

than the Lagrange approach. In addition, in order to

approach the same result with Lagrange approach,

solution network elements are needed in a smaller

structure. Given all these disadvantages of the

classical Euler method, the CEL method allows

much more efficient analysis.

Figure 4.1.0 : CEL Modeling Method for Soft

Body Projectile

In conclusion, the CEL approach allows for more

efficient fluid-solid body analysis by taking good

aspects of the Eulerian and Lagrangian approaches.

On the other hand, it is trying to get rid of the

disadvantages of Euler and Lagrange methods. The

disadvantage of the CEL method is that the user has

to be experienced while determining the solution

network volume. Figure 4.6 shows the element

deformation in CEL bird model.

mDiameter

DiameterDensity

MassBirdLengthCylinder 146.0]

6**[*4

2

Figure 4.1.2: Bird strike simulation on rigid

plate with CEL impactor model

4.2 SPH (Smoothed Particle Hydrodynamics)

Solution Technique

In addition to methods such as Lagrange, Euler and

ALE, SPH (Smooth Particules Hydrodynamics)

method has been developed in order to get rid of

solution network problems and to make more

efficient analyzes. Initially developed for the

calculations of astrophysical collisions at hypersonic

speeds in the 1970s, fluid-rigid interaction problems

from the beginning of the 1990s, collision

simulations, analyzes of fragile and bendable

structures, and analyzes subjected to high

deformation. The bird collision problem, which

occurs in large diameter deformation, is suitable for

use with the SPH method. [32]

Figure 4.2.0 SPH Modeling Method for Soft

Body Projectile

Fig.4.2.1 Finite element mesh and SPH particle

distribution

In addition to methods such as Lagrangian, Eulerian

and ALE, SPH (Smooth Particles Hydrodynamics)

method has been developed in order to get rid of

solution network problems and to make more

efficient analyzes. Initially developed for the

calculations of astrophysical collisions at hyper-

sonic speeds in the 1970s, fluid-rigid interaction

problems from the beginning of the 1990s, collision

simulations, analyzes of fragile and bendable

structures, and analyzes subjected to high

deformation. SPH method is suitable for use with

the bird strike problem with large deformation.

Thanks to the mesh-less structure of the SPH

method, there are no solution network problems

resulting from large deformations. The conventional

solid Lagrange solution significantly reduces the

step time in the elements, which are deformed

compared to the solution network and is fixed.

According to the Euler method, the SPH method

requires far fewer elements. It is also easy to follow

the deformation behavior of each particle as in the

Lagrange method. [22] [30] [33]

Figure 4.2.2: Bird strike simulation on rigid

plate with SPH impactor model

On the other hand, the SPH method also have some

disadvantages. There is a high memory and CPU

requirement for the calculation, and this problem is

inherited by parallel multiprocessor computers.

Another disadvantage is that, when the boundary

conditions are determined, the relative value of the

particles deviates from the true value when the

boundary conditions are exceeded.

4.3 Comparison of the Solution Teqniques

CEL and SPH finite element methods investigated

with advantages and disadvantages in this chapter

will be compared with one another in this section

and the method to be used within the scope of this

thesis will be selected. CEL and SPH methods give

more feasible results. On the other hand, in the SPH

method to be used as an analysis method in this

thesis study, birds will be expressed as particle and

rigid plate will be expressed according to Lagrange

solution network method. With the SPH method, the

greatest amount of deformations in the bird element

are represented most appropriately and the closest

results to the actual conditions are approached.

Heimbs (2010) made a table about advantages and

disadvantage about of bird modeling methods. [30]

Table 4.3: Comparision between CEL and SPH

Method

5. Bird-strike analysis

5.1 Bird geometry validation.

In order to validate the bird geometry which is going

to be used in this thesis, it is used in a bird strike

analysis on a flat plate, and compared the results

with an experimental test and a numerical solution

found in literature research.

The displacement vs. time , strain vs. time and

reaction force vs. time histories of the plate were

recorded, For each test group, two experiments were

conducted UNDER CEL MODEL AND SPH

MODEL and the experimental results showed good

repeatability. For all the tests conducted, no damage

or failure was observed on the plate.

5.1.1 Test 1:

Fig 01 displays the experimental results for test No.

1, The actual impact velocities are 60 m/s on both

SPH Bird Model and CEL Bird. These values are

very close to the expected impact velocity of 60 m/s,

indicating the impact velocity control mechanism in

our experimental setup works effectively. The

displacement vs. time curves measured in the two

experiments coincide, suggesting very good

repeatability.Before 2.0 ms of time period the

displacement response shows the plate is under bird

impact while after 2.0 ms the fluctuation in

displacement is just a result of the free rebound of

the plate. The free rebound displacement fluctuates

above zero, indicating the plate is deformed

plastically after impacted by the bird. The strain

measurement in the two experiments as well as the

Kinetic energy absorption measurements show good

repeatability.

(a) CEL simulation with bird velocity of 60 ms-1

(b) SPH simulation with bird velocity of 60 ms-1

Figure 5-1: shows a 1.8 kg bird impacting the

10 mm thick AlCu4Mg1 plate at a velocity of

60 m/s

CEL model SPH model

Advantages Uses mesh

and gives

absolute

values.

No mesh

distortion,

constant time

step

Simple model

generation

Numerically

stable

simulations.

Impactor

boundary

clearly

defined

Good

representation

of splashing

behavior

Complex bird

splitting can

be simulated

Lower

computational

cost

Disadvantages Higher

computational

cost

Model

generation

more

complex

Hourglass

problems

No tensile

behavior

Splashing

behavior

difficult to

represent with

CEL

No clear outer

boundary.

Fine mesh

necessary in

impact zone:

expensive.

5.1.2 Dynamic Responses:

Kinetic energy absorption vs time

Deflection vs timeStrain Energy vs time

(a) Graphs of CEL method with bird velocity 60ms-

1.

(c) Graphs of SPH method with bird velocity 60ms-

1.

Fig 5.1.1: Graphs of kinetic energy, strain

energy and displacement at 60ms-1.

5.2 Test 2:

Fig. displays the experimental results for test No. 2.

The actual impact velocities are 70 m/ s on both


very close to the expected impact velocity of 70 m/s.

The displacement vs. time curves are measured in

the two experiments show good agreement.

The strain measurements and the Kinetic energy

absorption measurements in the two experiments

show good repeatability.

(a) CEL simulation with bird velocity of 70ms-1

(b) SPH simulation with bird velocity of 70ms-1.

Fig 5.2.0 : shows a 1.8 kg bird impacting the 10

mm thick AlCu4Mg1 plate at a velocity of 70

m/s



Deflection vs timeStrain Energy vs time

0.E+00

5.E+01

1.E+02

2.E+02

2.E+02

0.E+00

7.E-05

1.E-04

2.E-04

3.E-04

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1.E-03

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1.E-03

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Ener

gy

Time

Kinetic energy: ALLKE for Whole Model

-5.E+00

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gy

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Strain energy: ALLSE for Whole Model

-1.E-02

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1.E-03

1.E-03

1.E-03

1.E-03

1.E-03

2.E-03

Dis

pla

cem

ent

Time

From Field Data: U:U2 at part instance PANEL-1 node 2678

0.E+002.E+054.E+056.E+058.E+051.E+06

0.E+00

4.E-03

7.E-03

1.E-02

1.E-02

2.E-02

2.E-02

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Ene

rgy

Time


0.E+002.E+044.E+046.E+048.E+041.E+051.E+05

0.E+00

4.E-03

7.E-03

1.E-02

1.E-02

2.E-02

2.E-02

3.E-02

3.E-02

3.E-02

4.E-02

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8.E-02

Stra

in E

ner

gy

Time


-5.E+01

-4.E+01

-3.E+01

-2.E+01

-1.E+01

0.E+00

0.E+00

4.E-04

8.E-04

1.E-03

2.E-03

2.E-03

2.E-03

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4.E-03

4.E-03

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6.E-03

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8.E-03

Dis

pla

cem

ent

Time

From Field Data: U:U3 at part instance PANEL node 2279

0.E+00

5.E+01

1.E+02

2.E+02

2.E+02

3.E+02

0.E+00

8.E-05

2.E-04

2.E-04

3.E-04

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5.E-04

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Ener

gy

Time


-5.E+00

0.E+00

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2.E-04

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5.E-04

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Ener

gy

Time


(a) graphs of bird velocity 70m-1 in CEL method.

(b) graphs of bird velocity 70ms-1 in SPH method.

Fig 5.2.1 : graphs of kinetic energy, strain


5.3 Test 3:





The displacement vs. time curves measured in the

two experiments coincide.

Before 2.0 ms of time period the displacement

response shows the plate is under bird impact while

after 2.0 ms the fluctuation in displacement is just a

result of the free rebound of the plate. The free

rebound displacement fluctuates above zero,

indicating the plate is deformed plastically after

impacted by the bird. The strain measurement in the

two experiments as well as the Kinetic energy

absorption measurements show good repeatability.

(a) CEL simulation with bird velocity 80ms-1.

(b) SPH simulation with bird velocity 80ms-1.

Fig 5.3.1: shows a 1.8 kg bird impacting the 10

mm thick AlCu4Mg1 plate at a velocity of 80

m/s



Deflection vs time

Strain Energy vs time

-1.E-02

-1.E-02

-8.E-03

-6.E-03

-4.E-03

-2.E-03

0.E+00

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Ener

gy

Time


0.E+00

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Ene

rgy

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pla

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-5.E+00

0.E+00

5.E+00

1.E+01

2.E+01

2.E+01

3.E+01

3.E+01

0.E+00

8.E-05

2.E-04

2.E-04

3.E-04

4.E-04

5.E-04

6.E-04

7.E-04

7.E-04

8.E-04

9.E-04

1.E-03

1.E-03

1.E-03

1.E-03

1.E-03

1.E-03

1.E-03

Ener

gy

Time



(b) graphs of bird velocity 80ms-1 in SPH method.

Fig 5.3.1: graphs of kinetic energy, strain


5.4 Test 04:





The displacement vs. time curves measured in the

two experiments coincide.










(a) CEL simulation with bird velocity 90ms-1.

(b) SPH simulation with bird velocity 90ms-1.

Fig 5-7: shows a 1.8 kg bird impacting the 10 mm

thick AlCu4Mg1 plate at a velocity of 90 m/s.



Deflection vs time


-1.E-02

-1.E-02

-1.E-02

-8.E-03

-6.E-03

-4.E-03

-2.E-03

0.E+00D

isp

lace

men

t

Time

_U:U2 PI: PANEL-1 N: 2678

0.E+002.E+054.E+056.E+058.E+051.E+061.E+061.E+062.E+06

0.E+00

4.E-04

9.E-04

1.E-03

2.E-03

2.E-03

3.E-03

3.E-03

4.E-03

4.E-03

4.E-03

5.E-03

5.E-03

6.E-03

6.E-03

7.E-03

7.E-03

7.E-03

8.E-03

Ener

gy

Time


0.E+00

5.E+04

1.E+05

2.E+05

2.E+05

0.E+00

4.E-04

9.E-04

1.E-03

2.E-03

2.E-03

3.E-03

3.E-03

4.E-03

4.E-03

4.E-03

5.E-03

5.E-03

6.E-03

6.E-03

7.E-03

7.E-03

7.E-03

8.E-03

Ene

rgy

Time


-6.E+01

-5.E+01

-4.E+01

-3.E+01

-2.E+01

-1.E+01

0.E+00

Dis

pla

cem

en

t

Time

From Field Data: U:U3 at part instance PART-2-1 node 2279

050100150200250300350400

0

7.55008E-05

0.000150289

0.000225078

0.000300578

0.000375365

0.000450152

0.000525653

0.000600443

0.000675233

0.000750023

0.000825412

0.000900664

0.000975282

0.001050243

0.001125023

0.001200484

0.001275244

0.001350002

0.001425428

0.0015

Ener

gy

Time


-5.E+00

0.E+00

5.E+00

1.E+01

2.E+01

2.E+01

3.E+01

3.E+01

4.E+01

0.E+00

8.E-05

2.E-04

2.E-04

3.E-04

4.E-04

5.E-04

6.E-04

7.E-04

7.E-04

8.E-04

9.E-04

1.E-03

1.E-03

1.E-03

1.E-03

1.E-03

1.E-03

1.E-03

Axi

s Ti

tle

Axis Title


(a) Graphs of bird velocity 90m-1 in CEL method.

(b) graphs of bird velocity 90ms-1 in SPH

method.



5.5 Test 05:

Fig. 05 displays the experimental results for test No.

5. The actual impact velocities are 100 m/ s on both


very close to the expected impact velocity of 100

m/s. The displacement vs. time curves measured in

the two experiments coincide.










CEL simulation with bird velocity of 100ms-1.

SPH simulation bird velocity of 100ms-1.

Fig 5-9: shows a 1.8 kg bird impacting the 10 mm

thick AlCu4Mg1 plate at a velocity of 100 m/s.



Deflection vs time



-2.E-02

-2.E-02

-1.E-02

-5.E-03

0.E+00D

Isp

lace

men

t

Time


0.E+00

5.E+05

1.E+06

2.E+06

2.E+06

3.E+06

0.E+00

4.E-04

9.E-04

1.E-03

2.E-03

2.E-03

3.E-03

3.E-03

4.E-03

4.E-03

4.E-03

5.E-03

5.E-03

6.E-03

6.E-03

7.E-03

7.E-03

7.E-03

8.E-03

Ener

gy

Time


0.E+00

5.E+04

1.E+05

2.E+05

2.E+05

3.E+05

0.E+00

4.E-04

8.E-04

1.E-03

2.E-03

2.E-03

2.E-03

3.E-03

3.E-03

4.E-03

4.E-03

4.E-03

5.E-03

5.E-03

6.E-03

6.E-03

6.E-03

7.E-03

7.E-03

8.E-03

8.E-03

Ene

rgy

Time


-7.E+01

-6.E+01

-5.E+01

-4.E+01

-3.E+01

-2.E+01

-1.E+01

0.E+00

0.E+00

4.E-04

8.E-04

1.E-03

2.E-03

2.E-03

2.E-03

3.E-03

3.E-03

4.E-03

4.E-03

4.E-03

5.E-03

5.E-03

6.E-03

6.E-03

6.E-03

7.E-03

7.E-03

8.E-03

8.E-03

Dis

pla

cem

en

t

Time

From Field Data: U:U3 at part instance PANNEL node 2279

0.E+005.E+011.E+022.E+022.E+023.E+023.E+024.E+024.E+025.E+025.E+02

0.E+00

8.E-05

2.E-04

2.E-04

3.E-04

4.E-04

5.E-04

5.E-04

6.E-04

7.E-04

8.E-04

8.E-04

9.E-04

1.E-03

1.E-03

1.E-03

1.E-03

1.E-03

1.E-03

1.E-03

2.E-03

Ene

rgy

Time


-5.E+00

0.E+00

5.E+00

1.E+01

2.E+01

2.E+01

3.E+01

3.E+01

4.E+01

0.E+00

8.E-05

2.E-04

2.E-04

3.E-04

4.E-04

5.E-04

5.E-04

6.E-04

7.E-04

8.E-04

8.E-04

9.E-04

1.E-03

1.E-03

1.E-03

1.E-03

1.E-03

1.E-03

1.E-03

2.E-03

Ener

gy

Time


-3.E-02

-2.E-02

-2.E-02

-1.E-02

-5.E-03

0.E+00

0.E+00

8.E-05

2.E-04

2.E-04

3.E-04

4.E-04

5.E-04

5.E-04

6.E-04

7.E-04

8.E-04

8.E-04

9.E-04

1.E-03

1.E-03

1.E-03

1.E-03

1.E-03

1.E-03

1.E-03

2.E-03

Ener

gy

Time


Graphs of bird velocity 100ms-1 in SPH method.



6.0 Result:

Comparisons of results from different tests

In this section, the bird strike is simulated using the

Two-bird models CEL and SPH respectively. Fig

compares the simulation results with the

experimental measurements.

From the comparison of different properties of the

whole system when the bird velocity at 60 ms-1,

70ms-1,80 ms-1,90 ms-1,100 ms-1.

1. The curves of Kinetic Energy and Strain

Energy are behaving similar in sph and

experimet values are very near, whereas the

CEL mehtod is not providing values near to

the experimental values.

2. The displacement curve of CEL is Near to

the experimental values but it again

discontinued at the peak values wihout

exhibiting any rebounce framework in the

plate.

3. The strain energy curve of CEL is Near to

the experimental values but it again

discontinued at the peak values wihout

exhibiting any rebounce framework in the

plate.

7.0 Conclusion

The main purpose is to analyse a bird strike on

Aircraft structure using Abaqus/Explicit. Explicit

finite element method is used to analyze this type of

short duration highly nonlinear impact problem.

1. Within the scope of this thesis study,

detailed information about the bird crash

and the related regulations will be reached

and an analysis and evaluation of the bird

crash events will be presented.

2. The advantages and disadvantages of

available solution techniques such as (CEL)

Coupled Eulerian Legrangian and SPH

(Smooth Particle Hydrodynamics) methods

used in bird strike analyzes will be

examined and compared.

3. In addition, soft body impactor which is a

bird in this study, is going to be modeled

according to literature review. Cylindrical

bird geometry will be modeled by using

SPH (Smooth Particle Hydrodynamics)

solution technique.

4. The SPH method will be modeled again

from a previous work on bird strike and the

bird strike phenomenon will be examined

on a Aircraft structure which will be taken

as an example after the validity of the

parameters is proved. In this study, bird

strike analysis on a 10 mm thick AlCu4Mg1

plate will be carried out,

5. The effect of the change of solution net

density and the material thickness will be

examined.

6. Strain-strain amounts on the Crash will be

compared with the material properties and a

comment will be tried to be made.

0.E+00

5.E+05

1.E+06

2.E+06

2.E+06

3.E+06

0.E+00

4.E-04

7.E-04

1.E-03

1.E-03

2.E-03

2.E-03

3.E-03

3.E-03

3.E-03

4.E-03

4.E-03

4.E-03

5.E-03

5.E-03

5.E-03

6.E-03

6.E-03

6.E-03

7.E-03

7.E-03

8.E-03

8.E-03

Ener

gy

Time


0.E+00

5.E+04

1.E+05

2.E+05

2.E+05

3.E+05

3.E+05

0.E+00

4.E-04

7.E-04

1.E-03

1.E-03

2.E-03

2.E-03

3.E-03

3.E-03

3.E-03

4.E-03

4.E-03

4.E-03

5.E-03

5.E-03

5.E-03

6.E-03

6.E-03

6.E-03

7.E-03

7.E-03

8.E-03

8.E-03

Ener

gy

TIme


-7.E+01

-6.E+01

-5.E+01

-4.E+01

-3.E+01

-2.E+01

-1.E+01

0.E+00

1.E+01

0.E+00

4.E-04

8.E-04

1.E-03

2.E-03

2.E-03

2.E-03

3.E-03

3.E-03

4.E-03

4.E-03

4.E-03

5.E-03

5.E-03

6.E-03

6.E-03

6.E-03

7.E-03

7.E-03

8.E-03

8.E-03

Dis

pla

cem

en

t

Time

From Field Data: U:U3 at part instance PANNEL node 2279

8.0 References:

CCAR-25-R3 Airworthiness Standards, Transport

Category Aircrafts, Civil Aviation Administration of

China, 2001.

I. Smojver, D. Ivančević, Numerical simulation of

bird strike damage prediction in airplane flap

structure, Compos. Struct. 92 (2010) 2016–2026.

A. Airoldi, D. Tagliapiera, Bird Impact Simulation

against a Hybrid Composite and Metallic Vertical

Stabilizer, (2001) AIAA-2001-1390.

J. Reglero, M. Rodriíguez-Pérez, E. Solórzano, et

al., Aluminium foams as a filler for leading edges:

improvements in the mechanical behavior under bird

strike impact tests, Mater. Des. 32 (2) (2011) 907–

910.

J. Liu, Y.L. Li, X.C. Yu, et al., A novel design for

reinforcing the aircraft tail leading edge structure

against bird strike, Int. J. Impact Eng. 105 (2017)

89–101.

M.Y. Zhao, J.J. Li, Efficiency metallic leading edge

structure bird strike resistant design, Adv. Mater.

Res. 338 (2011) 84–89.

A. Riccio, R. Cristiano, S. Saputo, et al., Numerical

methodologies for simulating bird-strike on

composite wings, Compos. Struct. 202 (2008) 590–

602.

M.A. Lavoie, A. Gakwaya, M.N. Ensan, et al.,

Review of existing numerical methods and

validation procedure available for bird strike

modeling, International conference on

computational & experimental engineering and

sciences, 2 2007, pp. 111–118.

Y.J. Liu, Z. Li, Q. Sun, et al., Separation dynamics

of large-scale fairing section: a fluid–structure

interaction study, Proc. Inst. Mech. Eng. G J.

Aerosp. Eng. 227 (2013) 1767–1779.

R. Jain, K. Ramachandra, Bird impact analysis of

pre-stressed fan blades using explicit finite element

code, Proceedings of the International Gas Turbine

Congress Tokyo, 2003.

M. Guida, F. Marulo, M. Meo, et al., SPH–

Lagrangian study of bird impact on leading edge

wing, Compos. Struct. 93 (2011) 1060–1071.

J. Liu, Y.L. Li, F. Xu, The numerical simulation of a

bird-impact on an aircraft windshield by using the

SPH method, Adv. Mater. Res. 33 (2008) 851–856.

R. Budgey, The Development of Artificial Bird

Designs for Bird-Strike Resistance Testing,

IBSC25/WP-IE3, Amsterdam, 2000.

J. Liu, Y.L. Li, Inversion on the constants of bird

body constitutive model I: study on bird impact

plane test, Journal of Aeronautics 32 (5) (2011)

802–811.

S.C. Fei, Q. Sun, Investigation on parameters

calibration for the J-C failure model of aluminum

alloy, Computer Simulation 30 (9) (2013) 46–50.

N. Li, Y.L. Li, W.G. Guo, Comparison of

mechanical properties and their temperature

dependencies for three aluminum alloys under

dynamic load, Acta Aeronauticaet Astronautical

Sinica 29 (4) (2008) 903–908.

Y.J. Liu, Q. Sun, A dynamic ductile fracture model

on the effects of pressure, Lode angle and strain rate,

Mater. Sci. Eng. A 589 (2014) 262–270.

Y.J. Liu, Q. Sun, X.L. Fan, et al., A stress-invariant

based multi-parameters ductile progressive fracture

model, Mater. Sci. Eng. A 576 (2013) 337–345.

X. Liang, Damage accumulation and fracture

initiation in uncracked ductile solids subject to

triaxial loading, Int. J. Solids Struct. 44 (2007)

5163–5181.

M.Dakshina Moorthy is currently

pursuing her M.Tech (Mechanical Engineering) Machine

Design domain in Sri Vani Group of Institutions, Chevuturu Village,G.Konduru Mandalam,Krishna

District, Vijayawada,Andhra Pradesh.

He completed her graduation in Sri Venkateswara Colleeg of

Engineering,Tirupathi,Andhra Pradesh. His areas of interests

includes Machine Design, Advanced Strength of Materials, Finete

Element analysis.

Mr.T.Chakravarhi was born in 1985.he

received his mtech &Btech from jntuh in (2014&2006).at

present he is working as assistant professor and head

Mech department at srivani group of

institutions,chevutur.he has six years of teaching

experience and 8 years of industrial experience.

Bird strike Analysis on Aircraft structure using SPH Model · 2020. 7. 30. · Bird strike Analysis...

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Transcript of Bird strike Analysis on Aircraft structure using SPH Model · 2020. 7. 30. · Bird strike Analysis...