FORCE MEASUREMENTS FOR AN OSCILLATING FOIL IN CONSTRAINED FLOW GRADUATION PROJECT. Oğuz KORKMAZ. Department of Aeronautical Engineering

Transcription

1 ISTANBUL TECHNICAL UNIVERSITY FACULTY OF AERONAUTICS AND ASTRONAUTICS FORCE MEASUREMENTS FOR AN OSCILLATING FOIL IN CONSTRAINED FLOW GRADUATION PROJECT Oğuz KORKMAZ Department of Aeronautical Engineering Thesis Advisor: Dr. İdil FENERCİOĞLU AYDIN January, 2019 i

2 ISTANBUL TECHNICAL UNIVERSITY FACULTY OF AERONAUTICS AND ASTRONAUTICS FORCE MEASUREMENTS FOR AN OSCILLATING FOIL IN CONSTRAINED FLOW GRADUATION PROJECT Oğuz KORKMAZ ( ) Department of Aeronautıcal Engineering Thesis Advisor: Dr. İdil FENERCİOĞLU AYDIN January, 2019 ii

3 Oğuz KORKMAZ,student of ITU Faculty of Aeronautics and Astronauticsstudent ID , successfully defended the graduation entitled FORCE MEASUREMENTS FOR AN OSCILLATING FOIL IN CONSTRAINED FLOW, which he prepared after fulfilling the requirements specified in the associated legislations, before the jury whose signatures are below. Thesis Advisor : Dr. İdil FENERCİOĞLU AYDIN... İstanbul Technical University Jury Members : Prof. Dr. N.L.Okşan ÇETİNER YILDIRIM... İstanbul Technical University Asst. Prof. Dr. Hayri ACAR... İstanbul Technical University Date of Submission : 02 January 2019 Date of Defense : 15 January 2019 iii

4 To my family and friends, iv

5 FOREWORD This thesis is about force measurements for an oscillating foil in constrained flow. January 2019 Oğuz KORKMAZ v

6 vi

7 TABLE OF CONTENTS Page TABLE OF CONTENTS... vii ABBREVIATIONS... viii SUMMARY... xii 1. INTRODUCTION Purpose of Thesis Flapping Wing Aerodynamics Motion Kinematics EXPERIMENTAL SETUP Determine Proper Channel Speed Setup for Flat Plate with Free Flow Setup for Flat Plate with Solid Side Wall POSTPROCESSING RESULTS AND DISCUSSIONS Effects of Side Wall on Power Generation CONCLUSIONS AND RECOMMENDATIONS Practical Application of This Study REFERENCES vii

8 ABBREVIATIONS c C P C Py C Pϴ C P total d d w f h h w k L M P P a Re s St t T U V y ΔT R η ϴ ϴ o ф α α eff : chord length (m), : power coefficient, : time-averaged power coefficient, : power coefficient due to plunging motion, : power coefficient due to pitching motion, : total power coefficient, C Py + C Pϴ : maximum total transverse distance swept by the foil trailing edge(m) : minimum distance between the trailing edge and the side wall inserts non-dimensionalized by c : flapping frequency (Hz) : non-dimensional plunge amplitude to chord ratio : distance between the two side wall inserts non-dimensionalized by c : reduced frequency : transverse force on the foil (N) : moment about the foil pivot point (Nm) : power developed (W) : time averaged power (W) : maximum power available, : Reynolds number based on free stream velocity and foil chord : span length (m) : Strouhal number : time : period of oscillation (s), : free-stream velocity (m/s) : translational velocity (m/s) : stroke reversal time, as a fraction of the flapping period : efficiency of power extraction : pitch motion velocity : pitch motion amplitude : phase angle between pitching and plunging motions : angle of attack : effective angle of attack viii

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10 LIST OF TABLES Page Table 2.1 : Investigation of the proper channel speed...11 Table 2.2 : Experiment scheme...14 x

11 LIST OF FIGURES Page Figure 1.1 : Annual and estimated world population and energy demand (Omer, 2008)...1 Figure 1.2 : Primary Energy Consumotion (Quadrillion Btu) (Url-1)...2 Figure 1.3 : World oil productions changes over the years(omer, 2008)...2 Figure 1.4 : Volume of oil discovered worldwide (Omer, 2008)...3 Figure 1.5 : Schematic of angle of attack and force directions throughout the flapping cycle of a foil generating positive power...4 Figure 1.6 : Plunging motion y and pitching motion θ of the foil, and the associated angle of attack α. Lift L, drag D and moment M about the pivot point also shown...6 Figure 2.1 : Force/Torque sensor Nano25 IP68 (ATI)...8 Figure 2.2 : Sensing range and resolution of the F/T sensor...8 Figure 2.3 : Force/Moment Sensor Assembly...9 Figure 2.4 : Variation of plunge and pitch motions...10 Figure 2.5 : Motion kinematics of the flat plate...10 Figure 2.6 : Experimental setup...12 Figure 2.7 : Top and bottom views of experimental setup...13 Figure 2.8 : Experimental setup with side walls...13 xi

12 THESIS TITLE IN ENGLISH HERE SUMMARY Summary page will be made after the comments in the result section. Completed during the presentation of the thesis will be available. xii

13 1. INTRODUCTION 1.1 Purpose of Thesis The need for energy is increasing along with the increasing population and industrial development. A recent World Energy Council (WEC) study found that without any change in our current practice, the world energy demand in 2020 would be 50 80% higher than 1990 levels. According to a recent USA Department of Energy (DoE) report, annual energy demand will increase which is given in Figure 1.1 (Omer, 2008). Recently, there are major innovative developments in the field of technology which facilitate the lives of populations, but the requirement of energy is an obligation. Convenient and attainable habitual life can only be carried out with supplied energy. Figure 1.1 : Annual and estimated world population and energy demand (Omer, 2008). At present, a great percentage of the world's energy supply demands on fossil sources (Chu, 2012). Primary energy consumption between the year 1949 to 2017 is given in Figure 1.2 (Url- 1). However, mankind is facing the problem of resource limitation and the disaster of environmental pollution by producing harmful gas emissions (Karakas, 2016). 1

14 Figure 1.2 : Primary Energy Consumption (Quadrillion Btu) (Url-1). Technological progress has dramatically changed the world in a variety of ways. It has, however, also led to developments, e.g., environmental problems, which threaten man and nature. Build-up of carbon dioxide and other Greenhouse Gases (GHGs) is leading to global warming with unpredictable but potentially catastrophic consequences. When fossil fuels burn, they emit toxic pollutants that damage the environment and people's health with over 700,000 deaths resulting each year, according to the World Bank review of 2000(Omer, 2008). At the current rate of usage, taking into consideration population increases and higher consumption of energy by developing countries, oil resources, natural gas, and uranium will be depleted within a few decades (Figures 1.3 and 1.4). As for coal, it may take two centuries or so. One must, therefore, endeavor to take precautions today for a viable world for coming generations. Figure 1.3 : World oil productions changes over the years (Omer, 2008). 2

15 Figure 1.4 : Volume of oil discovered worldwide (Omer, 2008). The efficient solutions about fossil fuel problems lead us to renewable energy resources which are renewable, sustainable and ecological. There are many renewable energy production methods. Wind energy, hydropower, solar energy, and bioenergy are some of the effective alternatives for renewable and sustainable energy sources. Among the sustainable reserves, wind and hydropower have emerged as an important player in the energy space in recent decades. They also are believed to be a reliable and economically friendly electricity source (Schiermeier, 2008). As recent researches on turbine technology develop, wind turbines and hydro turbines have a great energy generation efficiency. And both of energy generators have some disadvantages which are cost, noise pollution and dangers for wildlife. The biggest disadvantage of wind energy in real life applications is that its continuity cannot be fully achieved (Ragheb, 2011). Wind power in many areas is too weak to feed the wind turbines. This creates a perfect field for flapping wing power generators(young, 2014). Flapping wing power generators might achieve similar performance levels at low speeds. The oscillation parameters for a flapping wing power generator are investigated in this study with the focus of energy extraction efficiency levels in the constrained flow. 3

16 1.2 Flapping Wing Aerodynamics Although this study concentrates on a flapping wing power generator, flapping wing propulsion is also an associated subject. The parameters required for high-efficiency drive can offer flapping wing aerodynamics as a different alternative to conventional designs. Therefore, flapping wings can easily progress in research in the field of high-efficiency energy production. Therefore, in this section, advances in the field of flapping wing propulsion are briefly reviewed. It is well known that flapping wings can be used either as thrust and power generators. The most effective parameter for determining whether an airfoil generates thrust or extract power from the free stream is its effective angle of attack. A flapping wing creates an effective angle of attack due to its pitching and plunging movements. This effective angle of attack is the difference between the geometric angle and the induced angle. Figure 1.5 : Schematic of angle of attack and force directions throughout the flapping cycle of a foil generating positive power (Young et al, 2014). With a large amplitude for pitching motion, energy flux is generated from flow to foil, which means power is generated. The power generation with a flapping wing is a known fact as shown by Platzer in 1996 (Jonas et al., 1996). Kinsey and Dumas numerically studied a single flapping foil and showed that the leading edge vortex (LEV) separation is an important mechanism to maximize the efficiency of power extraction and to determine the most suitable aerodynamic parameters for delaying the leading edge vortex (LEV) separation through the flapping cycle and to achieve high power (Kinsey and Dumas, 2008). 4

17 In most studies on energy extraction from fluid mechanics, sinusoidal pitching and plunging are considered as wing motion kinematics (Kinsey et al, 2011). Platzer et al. proposed an alternative airfoil movement in which a high angle of attack movement is maintained for a long time, followed by rapid pitching reversals (Platzer et al, 2009). The power coefficient increases linearly with wave amplitude (Dumas and Kinsey, 2006). However, it is difficult to say that efficiency always follows this trend. The position change of the pivot point has the effect of changing the phase angle between the pitch and plunge motions (Davids, 1999; Kinsey and Dumas, 2008). As a result of the works of Davids (1999) and Kinsey and Dumas (2008), it was shown that the pivot point in front of the middle chord position maximizes power generation efficiency. In this study, the pitch pivot point is selected at 0.44 chord (c) from the leading edge. In this thesis study, an experimental study was conducted to obtain forces acting on a flapping flat plate. 1.3 Motion Kinematics The instantaneous force measurements on the airfoil are acquired to examine the power extracted from the free stream using the resulting aerodynamic force. The formulas of instantaneous aerodynamic power equation (1.1) and power coefficient equation (1.2), and time-averaged power coefficient equation (1.3), and efficiency equation (1.4) are given as, P = Lḣ + Mϴ (1.1) C P (t) = = C L + C M (1.2) C P = (1.3) η = = = C P (1.4) Where L, M, h, ϴ, and η represents lift, moment, plunge motion, pitch motion, and efficiency respectively, and d is the largest total distance swept by any portion of the foil. The Reynolds number equation (1.5), which is the ratio of inertial to viscous forces, is one of the principles defining flow parameters. The Reynolds number can be defined by the formula 5

18 wherein U is the free stream velocity, the characteristic length of L, and ν is the kinematic viscosity of the fluid. Re = (1.5) Another important parameter characterizing the type of vortex shedding in the wake of a flapping airfoil is the Strouhal number (St). This dimensionless parameter contains both the frequency and amplitude of oscillation and defined as; St = (1.6) where f is the flapping frequency, A is the peak-to-peak displacement of airfoil trailing edge (wake width). In this study, for simplicity and comparison purposes, Strouhal number values are calculated based on the displacement of the pivot point at quarter chord location. The reduced frequency, k (1.7) is a dimensionless parameter for measuring oscillation behavior and instability. Flapping frequency, f, the chord length, c, and the free stream velocity, U, define the reduced frequency like below: k = (1.7) Oscillating foil kinematics is the combination of plunge motion and pitching motion. The plunge movement is defined as the translation of the foil that is perpendicular to the free stream velocity. The pitching movement is the rotation of the airfoil from a fixed pivot point along the chord-wise planform. The effective angle of attack consists of a combination of the degrees of freedom results of these two motions, α eff. Figure 1.6 : Plunging motion y and pitching motion θ of the foil, and the associated angle of attack α. Lift L, drag D and moment M about the pivot point also shown (Young et al., 2014). 6

19 For this reason, the effective angle of attack α eff (t) is defined in equation (1.12). α eff (t) = ϴ(t) - (1.12) 2. EXPERIMENTAL SETUP 2.1 Experimental Setup Overview The experiments were carried out at the Trisonic Laboratory of the Faculty of Aeronautics and Astronautics, Istanbul Technical University, in the Water Channel facility, capable of conducting experiments in a closed circuit, free surface, large-scale water channel. The test section is made of transparent Plexiglas with a size of 1010 x 790 mm. The test section is formed of three segments with upstream and downstream PVC reservoirs. Water filtration is carried out in the following order; firstly, the filtered water to fill an external reservoir is passed through a filtering system consisting of 25 μ polypropylene sediment and 5 μ carbon filters. The filtering system is used parallel to the water channel in closed circuit system. The stationary water in the chamber section is forced by a centrifugal pump, accelerated through the flow regulators and then through the 2:1 contraction section to the test section. After the test section, the water flow is directed down into the reservoir and then sent back to the settling chamber with a pipe. The turbulent intensity of the channel is under 1% (Fenercioglu, 2010). By controlling the RPM of the centrifugal flow pump, the flow rate in the test section is adjusted by means of an ABB AC drive. The linearly varying flow rate is calibrated in the test section for a water depth of 708 mm. The flow rate range of the channel is 0 to 140 mm/s. The detailed description of the water channel can be found in Fenercioglu (2010). In this study, a rectangular non-profiled flat plate was used considering the low production costs and power output enhancement results (Usoh et. al., 2012). The digital particle imaging velocimetry (DPIV) system with Dynamic Studio software (Dantec Dynamics A/S) is used to determine the desired channel speed to obtain the Reynolds number Re= A six-component ATI Nano25 IP68 Force/Torque (F/T) sensor Figure 2.1 (ATI Industrial Automation, Inc.), which can be operated in water and is used to measure the forces and moments acting on the flapping foil (Url-2). The sensor range and resolution are shown in 7

20 Figure 2.2. Calibration SI is used, thus calibration ranges for the measurements are ±250N for force in x and y directions, ±6Nm for torques in same directions. The maximum amount of error expressed as a percentage of the full-scale load is called measurement uncertainty. The weight of the sensor used is kg, its length is 27.5 mm and its diameter is 28 mm (Url-2). Figure 2.1 : Force/Torque sensor Nano25 IP68 (ATI) (Url-2). Figure 2.2 : Sensing range and resolution of the F/T sensor (Url-2). The sensor is attached to the vertical cantilevered arrangement between the flat plate model and the pitch servo motor. The cylindrical z-axis is normally normal to the pitch-plunge plane. The sensor is mounted as close to the wing profile side as possible and the sensor cable is fixed so as not to affect the movement. The XY plane of the sensor is mounted at the root of the airfoil parallel to the plane of the lifting and drag forces. The addition moment also coincides with the Z-axis. Sensor axis is shown in Figure2.3. 8

21 Figure 2.3 : Force/Moment Sensor Assembly (Url-3). The airfoil chord and the y-axis of the sensor are coincident. Due to the moment of inertia of the motors, the experiment is repeated with the same conditions in order to eliminate the effects of force and moment. The aerodynamic force and moment data in the air are subtracted from the original data in the water. Reference data are taken before and after each experiment to eliminate the bias error in the measurements. Whether a bias error occurs is checked during post-processing and reference values are taken into account during calculations. As the force/torque sensor rotates with the model, the instantaneous lifting and drag force at different angles of attack are calculated using the Fx and Fy values in the sensor. Calibration coefficients are used during data collection, so the recorded data gives direct force and moment. The dynamic force and moment data were collected for 20 periods with a sampling rate of Hz for each experiment. The Kollmorgen / Danaher Motion AKM33E and AKM54K servo motors were used for pitch and plunge motions respectively for the flat plate test model. ServoSTAR S300 and S700 digital servo amplifiers were used for pitching and plunging movements respectively while the servo motors were connected to the computer. Motor motion profiles are manufactured by LabVIEW VI, a signal generator for the given amplitude and frequency. The airfoil kinematic motions are non-sinusoidal pitching and plunging where the plunging motion is followed by rapid pitching reversals. The motion of the foil is given in Figure 2.4, with a fixed cycle of translational velocity combined with a constant pitch angle is followed by a sinusoidal reversal 9

22 of the direction and pitch angle. The motion is indicated by reversed times, which vary as a fraction of the total cycle, ΔTR, ranging from ΔTR=0.1 for the rapid reversal to ΔTR=0.5 for complete sinusoidal motion (Platzer et al., 2009). Figure 2.4 : Variation of plunge and pitch motions (Platzer et al., 2009). Figure 2.5 : Motion kinematics of the flat plate (Karakas et al., 2016). And set constant at k=0.8. Ongoing physical properties are as follows: the Reynolds Number is Re=10000, the corresponding flapping frequency of f=0.125 Hz and free stream velocity of U =0.1 m/s in this experiment process. The experiment was performed with two different phase angles (ф=90o and ф=110o). Phase angle is the angle between the pitch and plunge movements. The experiment was repeated for four different sidewall conditions. These are no side walls, dw/c = 0.1, dw/c = 0.5 and dw/c = 1.0 respectively as shown as Figure

23 2.2 Determination of Channel Speed One of the most important parts of the experiment is to find the desired free stream velocity. As seen in Formula 2.2, the pressure coefficient varies with the cube of the velocity. C P = (2.2) For this reason, digital particle imaging velocimetry (DPIV) system with Dynamic Studio software (Dantec Dynamics A/S) was used to determine the channel flow velocity. By measuring the movement of the particles between two light pulses, the velocity vectors are derived by deriving the particle-seeded stream from the lower parts of the target area. Due to this great importance of the channel flow velocity, the channel pump was tested in RPM values with the help of the DPIV system. Then, through Dynamic Studio software, speed vectors were removed by cross-correlation, vector statistics, and scalar derivatives. The results are as in Table 2.1 below: Table 2.1 : Investigation of the proper channel speed. As a result, it was determined that working at 1300 RPM with 708 mm water height would give a flow rate of 0.1 m/s. RPM μs Trigger Rate Number of Images Velocity (m/s) Setup for Flat Plate with Free Flow The sharp-edged rectangular flat Plexiglas plate has a chord length of c = 10 cm and a span of s= 30 cm and is mounted on a vertical incline around the point 0.44c. The servo motor that provides the Pitching motion is connected to the model with a connecting rod. This system is connected to the table in the linear direction providing plunging motion with the help of a coupling system and another servo motor connected to the linear table for plunging motion. To reduce the free surface effects, a rectangular upper-end plate sloping 30 outward on the vertically mounted flat plate is suspended. The lower end plate used for a 2D operation of the flat plate model is placed in such a way that it does not affect the pattern movement and twodimensional flow feature is provided in the constrained flow. The image of the experimental assembly is as shown in Figure

24 Figure 2.6 : Experimental setup (Fenercioglu, 2015). We can measure the forces and moments acting on the flapping foil using the ATI Nano25 IP68 Force/Torque sensor. Dynamic force and moment data were collected at Hz sampling rate in 20 periods. During this experiment, set the reduced frequency constant to k = 0.8. The Reynolds number, which provides the free flow rate of the water channel, U = 0.1 m/s, is Re = The flat plate profile is exposed to non-sinusoidal pitch and plunge oscillations combined with equal flapping frequencies of f = Hz. In the examined cases, it takes into account phase differences where ф = 90 and 110. Figure 2.7 : Top and bottom views of experimental setup (Karakas and Fenercioglu, 2016). 12

25 In order to investigate the effect of the side walls, two transparent Plexiglas plates, 5c in length, 0.05c in thickness and 30 inwardly inclined, are suspended from the upper-end plate on both sides of the flapping flat plate. The arrangement of the side walls is shown in Figure 2.7 and 2.8. The distance between the side walls and the oscillating flat plate (dw) is set so that the minimum dimensionless distance between the walls and the flat plate is not dimensioned according to the chord length in the case of the minimum and maximum positions ΔTR = 0.1 and ф = 110 degrees, dw/c = 0.1, 0.5 and 1.0. Then, in the dw/c=0.1 case, 10 datasets containing all the ΔTR and ф changes were taken and continued with 10 data sets in dw/c=0.5 and 1.0. Figure 2.8 : Experimental setup with side walls (Fenercioglu, 2015). The schema observed during the experiment is as in Table

26 Wal Effect - Experimental Cases Flat plate dimensions: c=10 cm, s=30 cm Pitch pivot position: 0.44c (from the leading edge) U =0.1 m/s, Re=10000 k=2πfc/u =0.8 Exp. Case No f [Hz] h ф [ ] Distance Between the Two Side Walls ϴo [ ] ΔTR No Side Wall-Case-1 0,125 1,05 90 No side walls (2D) 73 0,1 No Side Wall-Case-2 0,125 1,05 90 No side walls (2D) 73 0,2 No Side Wall-Case-3 0,125 1,05 90 No side walls (2D) 73 0,3 No Side Wall-Case-4 0,125 1,05 90 No side walls (2D) 73 0,4 No Side Wall-Case-5 0,125 1,05 90 No side walls (2D) 73 0,5 No Side Wall-Case-6 0,125 1, No side walls (2D) 73 0,1 No Side Wall-Case-7 0,125 1, No side walls (2D) 73 0,2 No Side Wall-Case-8 0,125 1, No side walls (2D) 73 0,3 No Side Wall-Case-9 0,125 1, No side walls (2D) 73 0,4 No Side Wall-Case-10 0,125 1, No side walls (2D) 73 0,5 CaseA-1 0,125 1, ,7 cm 73 0,1 CaseA-2 0,125 1, ,7 cm 73 0,2 CaseA-3 0,125 1, ,7 cm 73 0,3 CaseA-4 0,125 1, ,7 cm 73 0,4 CaseA-5 0,125 1, ,7 cm 73 0,5 CaseA-6 0,125 1, ,7 cm 73 0,1 CaseA-7 0,125 1, ,7 cm 73 0,2 CaseA-8 0,125 1, ,7 cm 73 0,3 CaseA-9 0,125 1, ,7 cm 73 0,4 CaseA-10 0,125 1, ,7 cm 73 0,5 CaseB-1 0,125 1, ,7 cm 73 0,1 CaseB-2 0,125 1, ,7 cm 73 0,2 CaseB-3 0,125 1, ,7 cm 73 0,3 CaseB-4 0,125 1, ,7 cm 73 0,4 CaseB-5 0,125 1, ,7 cm 73 0,5 CaseB-6 0,125 1, ,7 cm 73 0,1 CaseB-7 0,125 1, ,7 cm 73 0,2 CaseB-8 0,125 1, ,7 cm 73 0,3 CaseB-9 0,125 1, ,7 cm 73 0,4 CaseB-10 0,125 1, ,7 cm 73 0,5 CaseC-1 0,125 1, ,7 cm 73 0,1 CaseC-2 0,125 1, ,7 cm 73 0,2 CaseC-3 0,125 1, ,7 cm 73 0,3 CaseC-4 0,125 1, ,7 cm 73 0,4 CaseC-5 0,125 1, ,7 cm 73 0,5 CaseC-6 0,125 1, ,7 cm 73 0,1 CaseC-7 0,125 1, ,7 cm 73 0,2 CaseC-8 0,125 1, ,7 cm 73 0,3 CaseC-9 0,125 1, ,7 cm 73 0,4 CaseC-10 0,125 1, ,7 cm 73 0,5 Table 2.2 : Experiment scheme 14

27 3. POSTPROCESSING Data processing is, generally, "the collection and manipulation of items of data to produce meaningful information." (French, 1996) In this sense, it can be considered a subset of information processing, change of information in any way that can be detected by an observer. The term Data Processing (DP) has also been used to refer to a department within an organization responsible for the operation of data processing applications (Illingworth, 1997). After post-processing definition, we can examine the post-processing steps in this thesis. The first step in post-processing is to take counterweight. This is a correction made according to the average of the change of the data A and B received for 21 seconds before and after the data to be processed. This can be done using the Matlab code. The second step in post-processing is to take the phase average. With this process, the experimental data consisting of 20 periods is reduced to 1. The third step of post-processing is block average. In this process, we downscale effective 100 Hz sampling rate data to 1 period, in other words, it reduces the frequency of Hz to 100 Hz. In the fourth step of post-processing, wing movements are modeled. This includes the angle of attack and plunge amplitude values. These values are written to a file, the force data and the data received by air are written into this file. With this file, the motion dynamics are calculated. In the fifth step of the post-processing process, noisy data is cleared by a filtering model. With the help of Matlab, the files created in the previous operation are read with the help of various programs. The force data is filtered using the Low Pass Parabolic FFD Filter. In this filter, Pass Frequency is equal to 1.25 Hz and Stop Frequency is equal to 2.99 Hz. At the end of this filtering, noisy (high frequency) data is cleared. The processed data is now ready for use by passing through the required filter operations. In the sixth step of the post-processing process, lift and drag forces are derived from the force data derived as F x and F y. Because the sensor rotates with the model exposed to pitching and plunging movements, the lift force is calculated by dynamically transforming the forces measured for the kinematics of motion for each test case. The following equations are used for this process. L = F x cos(α) + F y sin(α) (3.1) 15

28 D = F x sin(α) - F y cos(α) (3.2) M = T z (3.3) C l = (3.4) C d = (3.5) C m = (3.6) Where, = kg/m 3, is the density of water. S and c are the wing surface area and chord length respectively. T z is the z-moment value from the sensor. In the seventh and last step of the post-processing process, the job parameters are rendered dimensionless. In this process, Plunge and Pitch Powers are collected and derived from these values C P, C D and C L values. 4. RESULTS AND DISCUSSIONS The comments of the results will be available at the end of the thesis presentation. 2 1,5 1 0,5 0-0,5-1 -1,5-2 -2,5-3 No Side Wall and ф=90 0 0,2 0,4 0,6 0,8 1 TR=0.1 TR=0.2 TR=0.3 TR=0.4 TR=0.5 16

29 No Side Wall and ф= ,2 0,4 0,6 0,8 1 TR=0.1 TR=0.2 TR=0.3 TR=0.4 TR= ,5 1 0,5 0-0,5-1 -1,5-2 -2,5-3 Case-A and ф=90 0 0,2 0,4 0,6 0,8 1 TR=0.1 TR=0.2 TR=0.3 TR=0.4 TR= Case-A and ф= ,2 0,4 0,6 0,8 1 TR=0.1 TR=0.2 TR=0.3 TR=0.4 TR=0.5 17

30 Case-B and ф=90 2 1,5 1 0,5 0-0,5-1 -1,5-2 -2, ,2 0,4 0,6 0,8 1 TR=0.1 TR=0.2 TR=0.3 TR=0.4 TR=0.5 Case-B and ф= ,2 0,4 0,6 0,8 1 TR=0.1 TR=0.2 TR=0.3 TR=0.4 TR= ,5 1 0,5 0-0,5-1 -1,5-2 -2,5-3 Case-C and ф=90 0 0,2 0,4 0,6 0,8 1 TR=0.1 TR=0.2 TR=0.3 TR=0.4 TR=0.5 18

31 C_p Mean Case-C and ф= ,2 0,4 0,6 0,8 1 TR=0.1 TR=0.2 TR=0.3 TR=0.4 TR= ,9 0,8 0,7 0,6 0,5 0,4 0,3 0,2 0, ,5 2 2,5 3 3,5 4 4,5 5 Delta_TR free flow fi=90 free flow fi=110 Case_A fi=90 Case_A fi=110 Case_B fi=90 Case_B fi=110 Case_C fi=90 Case_C fi= Effects of Side Wall on Power Generation The comments of the graphics will be made in the following process. 19

32 5. CONCLUSIONS AND RECOMMENDATIONS The comparative results and recommendations for future studies will be carried out in the future. 5.1 Practical Application of This Study Industrial examples of the study will be included in this section in the following process. 20

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