Post on 16-Jan-2017
VIDYA VIKAS INSTITUTE OF ENGINEERING & TECHNOLOGY MYSORE
Trailing Edge Control Surface Actuation of Aircraft Wing using SMA
Under the Guidance ofBharath shekar H.RAssistant ProfessorDepartment of Mechanical Engineering VVIET, Mysore
Submitted by:1.Gowtham J 4VM11ME0072.Manoj Kumar 4VM11ME0173.Mohammed Uwais 4VM11ME0194.Shreyas M N 4VM12ME410
INTRODUCTION
• Shape memory alloys are a unique class of metal alloys that can recover apparent permanent strains when they are heated above a certain temperature
• Shape memory alloys belongs to smart materials • There are two main types of SMA:
1. Nickel titanium Alloy.2. Copper-Aluminium Alloy.
• The discovery of the shape-memory effect were taken in the 1930s.• A. Ölander discovered the pseudoelastic behavior of the Au-Cd
alloy in 1932.
INTRODUCTION
INTRODUCTION
INTRODUCTION
Figure 2: Behavior of SMA Crystals Under Deformation, Heating, and Cooling
INTRODUCTION
• Shape memory alloys are the advanced materials that can be used as actuators as well as sensors. • The characteristic features of shape memory actuators
are: 1. High energy density2. High reversible strain makes them unique as compared to other
smart materials
• SMA “ remembers “and returns to its original shape even if it deforms. But it is not an simple elastic material.
TYPES OF TRANSFORMATION• Stress Induced Transformation
1. Super Elasticity or Psuedoelasticity Effect: When the SMA member is loaded in pure Austenite condition, it
undergoes a transformation to detwinned Martensite state, which also brings about a large deformation of Martensite because of the presence of external loading.
Figure 3: Psuedoelasticity Effect in SMA
TYPES OF TRANSFORMATION
2. R-Phase Transformation: During the cooling cycle of Ni-Ti alloy, an intermediate
phase called R phase is encountered just before the Martensite phase.
• Temperature Induced Transformation (Shape Memory Effect)There are two kinds of shape memories that are exhibited by an SMA member namely:
1. One- way shape memory effect2. Two-way shape memory effect
TYPES OF TRANSFORMATION
1. One Way Shape Memory Effect:
When a SMA is in its cold state, the metal can be bent or stretched & will hold those shapes until heated above the transmission temperature.
TYPES OF TRANSFORMATION
2. Two Way Shape Memory Effect:
The two way memory effect is the effect that the material remembers two different shapes, one at low temperature and one at high temperature.
APPLICATIONS
LITERATURE REVIEW• Tanaka[1] developed a constitutive law by assuming that the strain, temperature
and the martensite volume fraction are the only state variables, and developed the equations for the martensite volume fraction in terms of stress and temperature.
• Liang and Roger[2] developed the martensite volume fraction using cosine function.
• Brinson[3] developed one dimensional constitutive model for the thermomechanical behaviour of the shape memory alloys
• Michael[4] et.al designed a new shape memory alloy actuator that possesses impressive payload lifting capabilities.
• Peter Jardine[5] et.al developed the SMA torque tube which produced over 50 of span-wise twist.
• Benoit Berton[6] developed the mechanism for the trailing edge shape control. The mechanism is designed based on the original push-pull mechanism.
OBJECTIVE
• “To actuate the trailing edge control surface of aircraft wing using SMA wire”.
• Primary Objective:• Fabrication of wing according to NACA0022 standards.• Installation of SMA wire to the wing.
• Secondary Objective:• Conceptual design mechanism for the deployment of flap,
which converts the linear motion in to angular rotation.• To study the behaviour of SMA wire
METHODOLOGY
Conclusion
Results & Discussion
Experimental Analysis
Fabrication of Wing Structure with SMA Wire
Design of Flap Actuation Mechanism
Selection of Constitutive Material Model
Generation of Wing Structure using Catia
Selection of Wing Profile
METHODOLOGY• SELECTION OF WING PROFILE
The NACA airfoils are airfoil shapes for aircraft wings are developed by the
National Advisory Committee for Aeronautics, the standard wing structure
NACA0022 has been selected.
The NACA 4-digit wing sections define the profile by:
1. 1st digit describing maximum Camber as percentage of the cord.
2. 2nd digit describing the distance of maximum camber from the air foils leading
edge in 10% of the chord.
3. Last two digits describing maximum thickness of the airfoil as percent of the
chord.
• GENERATION OF WING STRUCTURE USING CATIA
• SELECTION OF CONSTITUTIVE MATERIAL MODEL
The material model developed by L.C Brinson can be considered as a benchmark. Hence it is used for further analysis.
METHODOLOGY• DESIGN OF FLAP ACTUATION MECHANISM
• FABRICATION OF WING STRUCTURE WITH SMA WIRE
Aluminium Sheet of 2mm thick is used for fabrication purpose and ϕ8mm Hinge rod is used. NiTiNol wire of 375µm is installed to the wing model.
METHODOLOGY• EXPERIMENTAL ANALYSIS Experimental Setup to Find Actuation Time and Load
Capacity
METHODOLOGY• Experimental Setup for Stress-Strain Curve
RESULTS AND DISCUSSIONS
•STRESS-STRAIN BEHAVIOUR OF SMA WIRE
RESULTS AND DISCUSSIONS
DEFLECTION v/s LOAD
From the graph above it is observed that the wire of diameter
375µm produces an angular deflection of 35º with a maximum load of 660 grms, for any further loading leads to decrease in actuation capability.
RESULTS AND DISCUSSIONS• TIME FOR ACTUATION
The experiment is conducted for the wire of diamete of 375µm. From the above graph it is observed that as the load increases the time for actuation also increases linearly. Upto 360 grms a constant actuation time is obtained and theareafter it varies linearly with respect to load.
RESULTS AND DISCUSSIONS
• TRANSFORMATION TEMPERATURES USING K-TYPE THERMOCOUPLE
RESULTS AND DISCUSSIONS
• Observations Trail 1:
Power supply is given to the circuit built and it can be observed that it takes 4 sec for the wire to heat up or start transforming. The voltage during these 4 sec is 1.21mV which is converted to temperature using k-type thermocouple. After 4 sec the wire temperature reaches to 70ºC i.e. 2.93mV where the maximum actuation is obtained. When power is cutoff it suddenly cools, i.e. at this phase transformation takes place. After this the wire slowly cools.
Trail 2: Experiment is carried out same as trail 1, in this case the wire starts loosing its property due to excessive loading and continuous usage of the wire.
RESULTS AND DISCUSSIONS• MATLAB ANALYSIS
1
2
3
45
RESULTS AND DISCUSSIONS
The above plot is generated using MATLAB codes written according to Brinson model. It consists of variations in stress, strain and temperature of SMA wire according to Brinson constitutive model.
Curve (1) = Linear elastic deformation upon loading.Curve (2) = Forward transformation upon loading.Curve (3) = Stress reversal upon unloading.Curve (4) = Rise in temperature to AS.
Curve (5) = Reverse transformation on increasing the temperature to AF.
CONCLUSION
• The primary objective of this work is to implement the SMA wire as an actuating member for a flap.
• The work required, the proper understanding of constitutive material models and working with material.
• Experiments have been carried out to understand the stress-strain behaviour of sample wire and the result obtained is satisfactory.
• Using NACA0022 the wing has been fabricated. • The actuation of control surface is analysed using the tested wire• The implementation is demonstrated on flap of a wing.• The flap rotation of 350 is achieved with the proposed
mechanism.• The Quantitative and Qualitative aspects like Stress-
Strain, Temperature, Load capacity, Time for actuation and Frequency has been studied.
FUTURE SCOPE OF WORK
• The flap actuation is performed with a simple mechanism. Hence there is a scope for further design and its optimization.• An optimized mechanism can be fabricated
and tested in the wind tunnel.• The concept mechanism can be implemented
for flap actuation in small aircrafts and UAV’s.• Composite models can be developed
considering SMA and proper resin system.
REFERENCES1. Tanaka, K. “A Thermomechanical Sketch of shape memory effect one dimensional tensile
behaviour”, Res Mechanica, Elsevier publishers, vol.2, issue.3,1986, pp59-72.2. Liang, C. “One-dimensional Thermomechanical Constitutive Relations for shape memory
materials”, Ph.d thesis, 1990, Virginia Tech.3. L.C. Brinson, “one-dimensional constitutive behaviour of shape memory alloys:
Thermomechanical derivation with non-constant material functions and redefined martensite internal variable”, Journal of Intelligent Material Systems and Structures, vol.4, April-1993, pp 229-241.
4. Michael, J.M, Constantinos Mavroidis, Charles Pfeiffer, “Design and dynamics of shape memory alloy wire bundle actuator”, Proceedings of the ANS, 8th Topical meeting on Robotics and Remote Systems, 1999
5. Jardine, AP, Bartley-Cho,JD, Flanagan,JS, “Improved design and performance of the SMA torque tube for the DARPA smart wing program” proceedings SPIE 3674,270, Newport Beach, CA, USA, Tuesday 02 March 1999
6. Benoit Berton, “Shape memory application: Trailing edge shape control”, Multifunctional structures/Integration of sensors and antennas, proceedings RTO-MP-AVT-141, France, 2006, pp 13.1-13.16
7. S.H.Adarsh, U.S. Mallikarjun “Effect of variation in applied force on transformation temperatures of NiTinol SMA’s”, Procedia Materials Science 2014, vol.5 697-703
8. FLEXINOL® Muscle Wire® Properties “DYNALLOY, Inc.” Makers of Dynamic Alloys 1562 Reynolds Avenue, Irvine, CA 92614
ThankYou..