Numerical and Experimental Investigation of the Design of a Piezoelectric De-Icing System for Small Rotorcraft Part 3/3: Numerical Model and Experimental Validation of Vibration-Based De-Icing of a Flat Plate Structure

The objective of this research project is divided in four parts: (1) to design a piezoelectric actuator-based de-icing system integrated to a flat plate experimental setup and develop a numerical model of the system with experimental validation, (2) use the experimental setup to investigate actuator activation with frequency sweeps and transient vibration analysis, (3) add ice layer to the numerical model and predict numerically stresses for different ice breaking with experimental validation, and (4) bring the concept to a blade structure for wind tunnel testing. This paper presents the first objective of this study. First, preliminary numerical analysis was performed to gain basic guidelines for the integration of piezoelectric actuators in a simple flat plate experimental setup for vibration-based de-icing investigation. The results of these simulations allowed to optimize the positioning of the actuators on the structure and the optimal phasing of the actuators for mode activation. A numerical model of the final setup was elaborated with the piezoelectric actuators optimally positioned on the plate and meshed with piezoelectric elements. A frequency analysis was performed to predict resonant frequencies and mode shapes, and multiple direct steady-state dynamic analyses were performed to predict displacements of the flat plate when excited with the actuators. In those steady-state dynamic analysis, electrical boundary conditions were applied to the actuators to excite the vibration of the plate. The setup was fabricated faithful to the numerical model at the laboratory with piezoelectric actuator patches bonded to a steel flat plate and large solid blocks used to mimic perfect clamped boundary condition. The experimental setup was brought at the National Research Council Canada (NRC) for testing with a laser vibrometer to validate the numerical results. The experimental results validated the model when the plate is optimally excited with an average of error of 20% and a maximal error obtained of 43%. However, when the plate was not efficiently excited for a mode, the prediction of the numerical data was less accurate. This was not a concern since the numerical model was developed to design and predict optimal excitation of structures for de-icing purpose. This study allowed to develop a numerical model of a simple flat plate and understand optimal phasing of the actuators. The experimental setup designed is used in the next phase of the project to study transient vibration and frequency sweeps. The numerical model is used in the third phase of the project by adding ice layers for investigation of vibration-based de-icing, with the final objective of developing and integrating a piezoelectric actuator de-icing system to a rotorcraft blade structure.

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Numerical and Experimental Investigation of the Design of a Piezoelectric De-Icing System for Small Rotorcraft Part 2/3: Investigation of Transient Vibration during Frequency Sweeps and Optimal Piezoelectric Actuator Excitation

Aerospace ◽

10.3390/aerospace7050049 ◽

2020 ◽

Vol 7 (5) ◽

pp. 49 ◽

Cited By ~ 3

Author(s):

Eric Villeneuve ◽

Christophe Volat ◽

Sebastian Ghinet

Keyword(s):

Steady State ◽

Numerical Model ◽

Flat Plate ◽

Piezoelectric Actuator ◽

Resonant Mode ◽

Sweep Rate ◽

Experimental Setup ◽

Transient Vibration ◽

Resonant Modes ◽

Frequency Sweeps

The objective of this research project is divided in four parts: (1) to design a piezoelectric actuator based de-icing system integrated to a flat plate experimental setup, develop a numerical model of the system and validate experimentally; (2) use the experimental setup to investigate actuator activation with frequency sweeps and transient vibration analysis; (3) add an ice layer to the numerical model, predict numerically stresses at ice breaking and validate experimentally; and (4) implement the concept to a blade structure for wind tunnel testing. This paper presents the second objective of this study, in which the experimental setup designed in the first phase of the project is used to study transient vibration occurring during frequency sweeps. Acceleration during different frequency sweeps was measured with an accelerometer on the flat plate setup. The results obtained showed that the vibration pattern was the same for the different sweep rate (in Hz/s) tested for a same sweep range. However, the amplitude of each resonant mode increased with a sweep rate decrease. Investigation of frequency sweeps performed around different resonant modes showed that as the frequency sweep rate tends towards zero, the amplitude of the mode tends toward the steady-state excitation amplitude value. Since no other transient effects were observed, this signifies that steady-state activation is the optimal excitation for a resonant mode. To validate this hypothesis, the flat plate was installed in a cold room where ice layers were accumulated. Frequency sweeps at high voltage were performed and a camera was used to record multiple pictures per second to determine the frequencies where breaking of the ice occur. Consequently, the resonant frequencies were determined from the transfer functions measured with the accelerometer versus the signal of excitation. Additional tests were performed in steady-state activation at those frequencies and the same breaking of the ice layer was obtained, resulting in the first ice breaking obtained in steady-state activation conditions as part of this research project. These results confirmed the conclusions obtained following the transient vibration investigation, but also demonstrated the drawbacks of steady-state activation, namely identifying resonant modes susceptible of creating ice breaking and locating with precision the frequencies of the modes, which change as the ice accumulates on the structure. Results also show that frequency sweeps, if designed properly, can be used as substitute to steady-state activation for the same results.

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Numerical and experimental validation of a morphed wing geometry using Price-Païdoussis wind-tunnel testing – CORRIGENDUM

The Aeronautical Journal ◽

10.1017/aer.2016.73 ◽

2016 ◽

Vol 120 (1230) ◽

pp. 1335-1335

Author(s):

R.M. Botez ◽

A. Koreanschi ◽

O. Sugar-Gabor

Keyword(s):

Wind Tunnel ◽

Experimental Validation ◽

Online Version ◽

Wind Tunnel Testing ◽

Correct Order ◽

Wing Geometry ◽

Tunnel Testing

The authors were listed incorrectly in the article by Botez(1). The authors should have appeared in the following order:A. Koreanschi, O. Sugar-Gabor and R.M. BotezThe article has now been updated with all authors listed in the correct order; this change has been made to the online version only.

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A Generalized Method for Flat Plates Impact Detection and Location

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.543.171 ◽

2013 ◽

Vol 543 ◽

pp. 171-175

Author(s):

Jose Andrés Somolinos ◽

Rafael Morales ◽

Carlos Morón ◽

Alfonso Garcia

Keyword(s):

Signal Processing ◽

Flat Plate ◽

Acoustic Signal ◽

Experimental Results ◽

Piezoelectric Sensors ◽

Experimental Setup ◽

Flat Plates ◽

Impact Detection ◽

Timing Difference

In the last years, many analyses from acoustic signal processing have been used for different applications. In most cases, these sensor systems are based on the determination of times of flight for signals from every transducer. This paper presents a flat plate generalization method for impact detection and location over linear links or bars-based structures. The use of three piezoelectric sensors allow to achieve the position and impact time while the use of additional sensors lets cover a larger area of detection and avoid wrong timing difference measurements. An experimental setup and some experimental results are briefly presented.

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Experiences from the wind-tunnel testing of the Hardanger Bridge section model

IABSE Congress, Christchurch 2021: Resilient technologies for sustainable infrastructure ◽

10.2749/christchurch.2021.0335 ◽

2021 ◽

Author(s):

Bartosz Siedziako ◽

Ole Øiseth

Keyword(s):

Wind Tunnel ◽

Superposition Principle ◽

Higher Order ◽

Lessons Learned ◽

Order Effects ◽

Experimental Setup ◽

Wind Tunnel Testing ◽

Section Model ◽

Higher Order Effects ◽

Tunnel Testing

<p>This paper presents an overview of the lessons learned and results from the extensive wind tunnel testing of the Hardanger bridge using a new experimental setup. Special attention is given to the reliability of wind tunnel results, the validity of the superposition principle, the presence of higher- order effects, and the importance of horizontal motion.</p>

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Experimental validation of a numerical model of busbar systems

IEE Proceedings - Generation Transmission and Distribution ◽

10.1049/ip-gtd:19951489 ◽

1995 ◽

Vol 142 (1) ◽

pp. 65 ◽

Cited By ~ 7

Author(s):

O. Battauscio

Keyword(s):

Numerical Model ◽

Experimental Validation

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Numerical model and experimental validation of the heat transfer in air cooled solar photovoltaic panel

Thermal Science ◽

10.2298/tsci16s4071r ◽

2016 ◽

Vol 20 (suppl. 4) ◽

pp. 1071-1081 ◽

Cited By ~ 3

Author(s):

Senthil Ranganathan ◽

Natarajan Elumalai ◽

Puja Natarajan Priyadharshini

Keyword(s):

Heat Transfer ◽

Numerical Model ◽

Experimental Validation ◽

Solar Photovoltaic ◽

Photovoltaic Panel

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Edge Cooling of a Fuel Cell during Aerial Missions by Ambient Air

Micromachines ◽

10.3390/mi12111432 ◽

2021 ◽

Vol 12 (11) ◽

pp. 1432

Author(s):

Lev Zakhvatkin ◽

Alex Schechter ◽

Eilam Buri ◽

Idit Avrahami

Keyword(s):

Fuel Cell ◽

Numerical Model ◽

Wind Tunnel ◽

Boundary Conditions ◽

Air Temperature ◽

Numerical Models ◽

Heat Removal ◽

Ambient Air ◽

Experimental Setup ◽

Good Agreement

During aerial missions of fuel-cell (FC) powered drones, the option of FC edge cooling may improve FC performance and durability. Here we describe an edge cooling approach for fixed-wing FC-powered drones by removing FC heat using the ambient air during flight. A set of experiments in a wind tunnel and numerical simulations were performed to examine the efficiency of FC edge cooling at various flight altitudes and cruise speeds. The experiments were used to validate the numerical model and prove the feasibility of the proposed method. The first simulation duplicated the geometry of the experimental setup and boundary conditions. The calculated temperatures of the stack were in good agreement with those of the experiments (within ±2 °C error). After validation, numerical models of a drone’s fuselage in ambient air with different radiator locations and at different flight speeds (10–30 m/s) and altitudes (up to 5 km) were examined. It was concluded that onboard FC edge cooling by ambient air may be applicable for velocities higher than 10 m/s. Despite the low pressure, density, and Cp of air at high altitudes, heat removal is significantly increased with altitude at all power and velocity conditions due to lower air temperature.

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