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Metrology of Shock Waves

A special issue of Sensors (ISSN 1424-8220). This special issue belongs to the section "Physical Sensors".

Deadline for manuscript submissions: closed (20 May 2023) | Viewed by 33077

Special Issue Editors


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Laboratoire d'Analyse et d'Architecture des Systemes (LAAS), Centre National de la Recherche Scientifique (CNRS), 31031 Toulouse, France
Interests: microtechnologies, MEMS, microsensors
Special Issues, Collections and Topics in MDPI journals

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Guest Editor
Commissariat à l’Energie Atomique et aux énergies alternatives (CEA), Direction des Applications Militaires, 46500 Gramat, France
Interests: ultrafast metrology; optical sensors

Special Issue Information

Dear Colleagues,

The study of shock waves is required for a lot of civil and military applications. The metrology of these events is still a resarch area as it combines an often harsh environment and dynamic measurements.

The content of this Special Issue deals with progress in the metrology of shock waves and adresses all the measurement chains (from transducer to data analysis) by taking into account sensors technologies, performance characterization (calibration, estimation of measurement uncertainties, etc.), and modelling.

We invite authors to contribute original research articles as well as review articles that stimulate the continuing effort towards innovative solutions for the metrology of shock waves.

Potential topics include but are not limited to the following:

- New transducers and sensors (pressure, velocity, temperature, stress, etc.) using different principle (mechanical, optical, etc.);

- Wireless sensors;

- Dynamic calibration;

- Metrology in real environments;

- The effect of shock waves on materials or infrastructures (in air, solid, water, etc.).

Dr. Patrick Pons
Dr. Jérome Luc
Guest Editors

Manuscript Submission Information

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Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • shock waves
  • metrology
  • ultrafast sensors
  • dynamic calibration

Published Papers (14 papers)

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Research

13 pages, 3861 KiB  
Article
Capacitive Effect and Electromagnetic Coupling on Manganin Gauge Limiting the Bandwidth for Pressure Measurements under Shock Conditions
by Antony Coustou, Alexandre Lefrançois, Patrick Pons and Yohan Barbarin
Sensors 2023, 23(14), 6583; https://0-doi-org.brum.beds.ac.uk/10.3390/s23146583 - 21 Jul 2023
Viewed by 546
Abstract
In this study, we investigated the capacitive effect and the electromagnetic coupling on the measurement chain induced by impact experiments with a gas gun or powder gun. Reduced bandwidth and noise were noticed on experimental signals. Rogowski coil measurements were added on the [...] Read more.
In this study, we investigated the capacitive effect and the electromagnetic coupling on the measurement chain induced by impact experiments with a gas gun or powder gun. Reduced bandwidth and noise were noticed on experimental signals. Rogowski coil measurements were added on the cables to characterize the electromagnetic coupling. The perturbation currents on the cables were quantified depending on the configuration. The gauge, the transmission line and the conditioning system were modeled. The calculations reproduced the electrical wave arrival time, the transmission line transfer impedance and the conditioning system transfer impedance; and the bandwidth limitation has been displayed. A capacitive effect with the piezoresistive manganin gauge embedded into the sample was identified, depending on the experimental setup. Full article
(This article belongs to the Special Issue Metrology of Shock Waves)
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22 pages, 7120 KiB  
Article
Toward Improvements in Pressure Measurements for Near Free-Field Blast Experiments
by Maylis Lavayssière, Alexandre Lefrançois, Bernard Crabos, Marc Genetier, Maxime Daudy, Sacha Comte, Alan Dufourmentel, Bruno Salsac, Frédéric Sol, Pascal Verdier and Patrick Pons
Sensors 2023, 23(12), 5635; https://0-doi-org.brum.beds.ac.uk/10.3390/s23125635 - 16 Jun 2023
Cited by 1 | Viewed by 950
Abstract
This paper proposes two ways to improve pressure measurement in air-blast experimentations, mostly for close-in detonations defined by a small-scaled distance below 0.4 m.kg−1/3. Firstly, a new kind of custom-made pressure probe sensor is presented. The transducer is a piezoelectric commercial, [...] Read more.
This paper proposes two ways to improve pressure measurement in air-blast experimentations, mostly for close-in detonations defined by a small-scaled distance below 0.4 m.kg−1/3. Firstly, a new kind of custom-made pressure probe sensor is presented. The transducer is a piezoelectric commercial, but the tip material has been modified. The dynamic response of this prototype is established in terms of time and frequency responses, both in a laboratory environment, on a shock tube, and in free-field experiments. The experimental results show that the modified probe can meet the measurement requirements of high-frequency pressure signals. Secondly, this paper presents the initial results of a deconvolution method, using the pencil probe transfer function determination with a shock tube. We demonstrate the method on experimental results and draw conclusions and prospects. Full article
(This article belongs to the Special Issue Metrology of Shock Waves)
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15 pages, 2852 KiB  
Article
Shock Properties Characterization of Dielectric Materials Using Millimeter-Wave Interferometry and Convolutional Neural Networks
by Jérémi Mapas, Alexandre Lefrançois, Hervé Aubert, Sacha Comte, Yohan Barbarin, Maylis Lavayssière, Benoit Rougier and Alexandre Dore
Sensors 2023, 23(10), 4835; https://0-doi-org.brum.beds.ac.uk/10.3390/s23104835 - 17 May 2023
Viewed by 789
Abstract
In this paper, a neural network approach is applied for solving an electromagnetic inverse problem involving solid dielectric materials subjected to shock impacts and interrogated by a millimeter-wave interferometer. Under mechanical impact, a shock wave is generated in the material and modifies the [...] Read more.
In this paper, a neural network approach is applied for solving an electromagnetic inverse problem involving solid dielectric materials subjected to shock impacts and interrogated by a millimeter-wave interferometer. Under mechanical impact, a shock wave is generated in the material and modifies the refractive index. It was recently demonstrated that the shock wavefront velocity and the particle velocity as well as the modified index in a shocked material can be remotely derived from measuring two characteristic Doppler frequencies in the waveform delivered by a millimeter-wave interferometer. We show here that a more accurate estimation of the shock wavefront and particle velocities can be obtained from training an appropriate convolutional neural network, especially in the important case of short-duration waveforms of few microseconds. Full article
(This article belongs to the Special Issue Metrology of Shock Waves)
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13 pages, 4421 KiB  
Article
Analysis of the Overpressure Fields in a Shock Tube with Multi-Point Initiation
by Zhuo Chen, Huiqi Ren, Qiang Zhao, Songbai Zhou, Zhilin Long and Wei Liu
Sensors 2023, 23(10), 4743; https://0-doi-org.brum.beds.ac.uk/10.3390/s23104743 - 14 May 2023
Viewed by 1268
Abstract
Shock tubes can carry out dynamic mechanical impact tests on civil engineering structures. The current shock tubes mostly use an explosion with aggregate charge to obtain shock waves. Limited effort has been made to study the overpressure field in shock tubes with multi-point [...] Read more.
Shock tubes can carry out dynamic mechanical impact tests on civil engineering structures. The current shock tubes mostly use an explosion with aggregate charge to obtain shock waves. Limited effort has been made to study the overpressure field in shock tubes with multi-point initiation. In this paper, the overpressure fields in a shock tube under the conditions of single-point initiation, multi-point simultaneous initiation, and multi-point delayed initiation have been analyzed by combining experiments and numerical simulations. The numerical results match well with the experimental data, which indicates that the computational model and method used can accurately simulate the blast flow field in a shock tube. For the same charge mass, the peak overpressure at the exit of the shock tube with the multi-point simultaneous initiation is smaller than that with single-point initiation. As the shock waves are focused on the wall, the maximum overpressure on the wall of the explosion chamber near the explosion zone is not reduced. The maximum overpressure on the wall of the explosion chamber can be effectively reduced by a six-point delayed initiation. When the interval time is less than 10 ms, the peak overpressure at the nozzle outlet decreases linearly with the interval of the explosion. When the interval time is greater than 10 ms, the overpressure peak remains unchanged. Full article
(This article belongs to the Special Issue Metrology of Shock Waves)
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11 pages, 726 KiB  
Article
Demonstration of Pressure Wave Observation by Acousto-Optic Sensing Using a Self-Mixing Interferometer
by Sébastien Maqueda, Julien Perchoux, Clément Tronche, José Javier Imas González, Marc Genetier, Maylis Lavayssière and Yohan Barbarin
Sensors 2023, 23(7), 3720; https://0-doi-org.brum.beds.ac.uk/10.3390/s23073720 - 04 Apr 2023
Cited by 2 | Viewed by 1578
Abstract
In this paper, we demonstrate that a compact and inexpensive interferometric sensor based on the self-mixing effect in the laser cavity can be used for the characterization of shock waves. The sensor measures the changes in the refractive index induced by the shock [...] Read more.
In this paper, we demonstrate that a compact and inexpensive interferometric sensor based on the self-mixing effect in the laser cavity can be used for the characterization of shock waves. The sensor measures the changes in the refractive index induced by the shock wave. It is based on the self-mixing interferometry scheme. We describe the architecture of the dynamic sensor and the design of the experimental setup used for the characterization that involves a shock tube. Thus, we detail the experimental measurements for shock wave pressure amplitude of 5 bar and address their interpretation with regard to the most admitted models for acousto-optics. Full article
(This article belongs to the Special Issue Metrology of Shock Waves)
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11 pages, 1506 KiB  
Article
Temporally and Spatially Resolved Reflected Overpressure Measurements in the Extreme Near Field
by Andrew D. Barr, Sam E. Rigby, Sam D. Clarke, Dain Farrimond and Andy Tyas
Sensors 2023, 23(2), 964; https://0-doi-org.brum.beds.ac.uk/10.3390/s23020964 - 14 Jan 2023
Cited by 3 | Viewed by 5740
Abstract
The design of blast-resistant structures and protective systems requires a firm understanding of the loadings imparted to structures by blast waves. While empirical methods can reliably predict these loadings in the far field, there is currently a lack of understanding on the pressures [...] Read more.
The design of blast-resistant structures and protective systems requires a firm understanding of the loadings imparted to structures by blast waves. While empirical methods can reliably predict these loadings in the far field, there is currently a lack of understanding on the pressures experienced in the very near field, where physics-based numerical modelling and semi-empirical fast-running engineering model predictions can vary by an order of magnitude. In this paper, we present the design of an experimental facility capable of providing definitive spatially and temporally resolved reflected pressure data in the extreme near field (Z<0.5 m/kg1/3). The Mechanisms and Characterisation of Explosions (MaCE) facility is a specific near-field evolution of the existing Characterisation of Blast Loading (CoBL) facility, which uses an array of Hopkinson pressure bars embedded in a stiff target plate. Maraging steel pressure bars and specially designed strain gauges are used to increase the measurement capacity from 600 MPa to 1800 MPa, and 33 pressure bars in a radial grid are used to improve the spatial resolution from 25 mm to 12.5 mm over the 100 mm radius measurement area. In addition, the pressure bar diameter is reduced from 10 mm to 4 mm, which greatly reduces stress wave dispersion, increasing the effective bandwidth. This enables the observation of high-frequency features in the pressure measurements, which is vital for validating the near-field transient effects predicted by numerical modelling and developing effective blast mitigation methods. Full article
(This article belongs to the Special Issue Metrology of Shock Waves)
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24 pages, 11799 KiB  
Article
Transient Response of Miniature Piezoresistive Pressure Sensor Dedicated to Blast Wave Monitoring
by Kevin Sanchez, Bilel Achour, Anthony Coustou, Aurélie Lecestre, Samuel Charlot, Maylis Lavayssière, Alexandre Lefrançois, Hervé Aubert and Patrick Pons
Sensors 2022, 22(24), 9571; https://0-doi-org.brum.beds.ac.uk/10.3390/s22249571 - 07 Dec 2022
Cited by 2 | Viewed by 2327
Abstract
Blast waves generated by energetic materials involve very fast time variations in the pressure. One important issue for blast wave metrology is the accurate measurement (typical precision in the range of ±5% or better) of the static overpressure peak. For most near field [...] Read more.
Blast waves generated by energetic materials involve very fast time variations in the pressure. One important issue for blast wave metrology is the accurate measurement (typical precision in the range of ±5% or better) of the static overpressure peak. For most near field configurations, this measurement requires ultra-fast sensors with response times lower than a few microseconds. In this paper, we design, model, fabricate and characterize a new ultra-fast sensor using piezo-resistive gauges at the center of a miniaturized and rectangular silicon membrane. When a pressure step of 10 bar is applied to the membrane, the signal delivered to the sensor output presents dampened oscillations, with a resonant frequency of 20.6 MHz and quality factor of 24,700 ns after the arrival of the shock wave. After removing undesirable drifts that appear after 700 ns, we may expect the sensor to have a response time (at ±5%) of 1.2 µs. Consequently, the proposed pressure sensor could be advantageously used for the accurate measurement of static overpressure peaks in blast wave experiments. Full article
(This article belongs to the Special Issue Metrology of Shock Waves)
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17 pages, 5576 KiB  
Article
Measurement and Analysis of Shock Wave Pressure in Moving Charge and Stationary Charge Explosions
by Xuejiao Ma, Deren Kong and Yucheng Shi
Sensors 2022, 22(17), 6582; https://0-doi-org.brum.beds.ac.uk/10.3390/s22176582 - 31 Aug 2022
Cited by 4 | Viewed by 2383
Abstract
Shock wave pressure is one of the most important parameters in an explosion. However, there have been few experimental and analytical investigations of moving charge explosions. In this article, we present an experimental method to measure the shock wave pressure from a moving [...] Read more.
Shock wave pressure is one of the most important parameters in an explosion. However, there have been few experimental and analytical investigations of moving charge explosions. In this article, we present an experimental method to measure the shock wave pressure from a moving charge explosion. Tests of stationary charges and moving charges with speeds of 580 m/s, 703 m/s and 717 m/s were carried out. The shock wave pressure curves and parameters at different measurement points were obtained and analyzed. The theoretical calculation of the shock wave overpressure was studied and compared with the experimental result. The differences between the stationary charge and moving charge explosions were investigated. The results showed that the shock wave pressure distribution of a moving charge had strong directionality. The shock wave pressure parameters (including overpressure, arrival time, duration and impulse) were influenced by the charge’s moving velocity, direction angle and distance from the blast point. The shock wave overpressure value was greater than that of a stationary charge explosion at angles between 0° and 90°. The correlation model based on the velocity vector superposition method could describe the relationship of overpressure between the stationary charge and moving charge explosions. Full article
(This article belongs to the Special Issue Metrology of Shock Waves)
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11 pages, 1431 KiB  
Article
Frequency Bandwidth of Pressure Sensors Dedicated to Blast Experiments
by Mathieu Chalnot, Patrick Pons and Hervé Aubert
Sensors 2022, 22(10), 3790; https://0-doi-org.brum.beds.ac.uk/10.3390/s22103790 - 17 May 2022
Cited by 2 | Viewed by 2399
Abstract
New broadband (>1 MHz) pressure sensors are regularly reported in the literature to measure the overpressure of blast waves. However, the frequency bandwidth needed to accurately measure such overpressure has not yet been clearly discussed. In this article, we present a methodology to [...] Read more.
New broadband (>1 MHz) pressure sensors are regularly reported in the literature to measure the overpressure of blast waves. However, the frequency bandwidth needed to accurately measure such overpressure has not yet been clearly discussed. In this article, we present a methodology to determine the bandwidth required to estimate the overpressure magnitude at the front of a blast wave, in order to obtain a desired estimation accuracy. The bandwidth is derived here by using Kingery and Bulmash data. Full article
(This article belongs to the Special Issue Metrology of Shock Waves)
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13 pages, 6855 KiB  
Communication
Analysis of Shock Wave Interaction with an Obstacle by Coupling Pressure Measurements and Visualization
by Antoine Gautier, Isabelle Sochet and Sébastien Courtiaud
Sensors 2022, 22(9), 3325; https://0-doi-org.brum.beds.ac.uk/10.3390/s22093325 - 26 Apr 2022
Cited by 3 | Viewed by 2508
Abstract
Small-scale experiments are a good means of carrying out explosion and shock wave measurements. Commonly, the shock wave is tracked thanks to pressure sensors and sometimes with a high-speed camera. In the present study, these methods were used to analyze the interaction of [...] Read more.
Small-scale experiments are a good means of carrying out explosion and shock wave measurements. Commonly, the shock wave is tracked thanks to pressure sensors and sometimes with a high-speed camera. In the present study, these methods were used to analyze the interaction of a shock wave with an obstacle of simple geometry. The primary aim of the study was to demonstrate the need to correlate these different methods in order to analyze certain phenomena related to the three-dimensional interaction of a shock wave with an object. The correlation between the overpressure and the visualization made it possible to carry out a complex analysis. The visualization was carried out simultaneously on two planes, from the front and top views, thanks to the optical setup. Shock wave characteristics were taken at ground level downstream of the obstacle with pressure gauges. The correlation of the images obtained allows the identification of the waves on the profile and their contribution in intensity. Full article
(This article belongs to the Special Issue Metrology of Shock Waves)
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15 pages, 2252 KiB  
Article
Effect of the Dynamic Response of a Side-Wall Pressure Measurement System on Determining the Pressure Step Signal in a Shock Tube Using a Time-of-Flight Method
by Andrej Svete, Francisco Javier Hernández Castro and Jože Kutin
Sensors 2022, 22(6), 2103; https://0-doi-org.brum.beds.ac.uk/10.3390/s22062103 - 09 Mar 2022
Cited by 16 | Viewed by 1925
Abstract
Technological progress demands accurate measurements of rapidly changing pressures. This, in turn, requires the use of dynamically calibrated pressure meters. The shock tube enables the dynamic characterization by applying an almost ideal pressure step change to the pressure sensor under calibration. This paper [...] Read more.
Technological progress demands accurate measurements of rapidly changing pressures. This, in turn, requires the use of dynamically calibrated pressure meters. The shock tube enables the dynamic characterization by applying an almost ideal pressure step change to the pressure sensor under calibration. This paper evaluates the effect of the dynamic response of a side-wall pressure measurement system on the detection of shock wave passage times over the side-wall pressure sensors installed along the shock tube. Furthermore, it evaluates this effect on the reference pressure step signal determined at the end-wall of the driven section using a time-of-flight method. To determine the errors in the detection of the shock front passage times over the centers of the side-wall sensors, a physical model for simulating the dynamic response of the complete measurement chain to the passage of the shock wave was developed. Due to the fact that the use of the physical model requires information about the effective diameter of the pressure sensor, special attention was paid to determining the effective diameter of the side-wall pressure sensors installed along the shock tube. The results show that the relative systematic errors in the pressure step amplitude at the end-wall of the shock tube due to the errors in the detection of the shock front passage times over the side-wall pressure sensors are less than 0.0003%. On the other hand, the systematic errors in the phase lag of the end-wall pressure signal in the calibration frequency range appropriate for high-frequency dynamic pressure applications are up to a few tens of degrees. Since the target phase measurement uncertainty of the pressure sensors used in high-frequency dynamic pressure applications is only a few degrees, the corrections for the systematic errors in the detection of the shock front passage times over the side-wall pressure sensors with the use of the developed physical dynamic model are, therefore, necessary when performing dynamic calibrations of pressure sensors with a shock tube. Full article
(This article belongs to the Special Issue Metrology of Shock Waves)
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21 pages, 2276 KiB  
Article
Experimental and Analytical Study of under Water Pressure Wave Induced by the Implosion of a Bubble Generated by Focused Laser
by Zhaofeng Han, Cyril Mauger, Thibaut Chaise, Thomas Elguedj, Michel Arrigoni, Mahmoud El Hajem and Nicolas Boisson
Sensors 2021, 21(14), 4800; https://0-doi-org.brum.beds.ac.uk/10.3390/s21144800 - 14 Jul 2021
Cited by 2 | Viewed by 2692
Abstract
In various domains of material processing, such as surface cleaning and surface treatment, cavitation phenomenon may become an alternative to traditional methods if this phenomenon is well understood. Due to experimental and mathematical difficulties in theoretical models, it is still a challenge to [...] Read more.
In various domains of material processing, such as surface cleaning and surface treatment, cavitation phenomenon may become an alternative to traditional methods if this phenomenon is well understood. Due to experimental and mathematical difficulties in theoretical models, it is still a challenge to accurately measure the physical mechanism of the fluid/structure interactions. In this study, we verified the feasibility of using polyvinylidene fluoride (PVDF) sensors to quantitatively measure the under-water pressure wave generated by the collapse of a single cavitation bubble. The electrical signal obtained by PVDF can be converted into pressure information only by using the sensor material parameters provided by the supplier. During the conversion process, only the capacitance of the acquisition chain needs to be additionally measured. At the same time, a high-speed video recording system was used to visualize the evolution of the cavitation bubble. The Gilmore analytical model and an associated wave propagation model were used to simulate the pressure peak of the first collapse of the cavitation bubble. This theoretical pressure was compared with the experimental results. The result showed that, for bubbles with a normalized standoff distance γ larger than 5, the PVDF sensor had the ability to quantitatively measure the pressure wave generated by a single cavitation bubble. Full article
(This article belongs to the Special Issue Metrology of Shock Waves)
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11 pages, 3177 KiB  
Communication
Evaluation of Shock Tube Retrofitted with Fast-Opening Valve for Dynamic Pressure Calibration
by Eynas Amer, Mikolaj Wozniak, Gustav Jönsson and Fredrik Arrhén
Sensors 2021, 21(13), 4470; https://0-doi-org.brum.beds.ac.uk/10.3390/s21134470 - 29 Jun 2021
Cited by 12 | Viewed by 2641
Abstract
Accurate dynamic pressure measurements are increasingly important. While traceability is lacking, several National Metrology Institutes (NMIs) and calibration laboratories are currently establishing calibration capacities. Shock tubes generating pressure steps with rise times below 1 μs are highly suitable as standards for dynamic pressures [...] Read more.
Accurate dynamic pressure measurements are increasingly important. While traceability is lacking, several National Metrology Institutes (NMIs) and calibration laboratories are currently establishing calibration capacities. Shock tubes generating pressure steps with rise times below 1 μs are highly suitable as standards for dynamic pressures in gas. In this work, we present the results from applying a fast-opening valve (FOV) to a shock tube designed for dynamic pressure measurements. We compare the performance of the shock tube when operated with conventional single and double diaphragms and when operated using an FOV. Different aspects are addressed: shock-wave formation, repeatability in amplitude of the realized pressure steps, the assessment of the required driver pressure for realizing nominal pressure steps, and economy. The results show that using the FOV has many advantages compared to the diaphragm: better repeatability, eight times faster to operate, and enables automation of the test sequences. Full article
(This article belongs to the Special Issue Metrology of Shock Waves)
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22 pages, 1247 KiB  
Article
PVDF Based Pressure Sensor for the Characterisation of the Mechanical Loading during High Explosive Hydro Forming of Metal Plates
by Jérémie Tartière, Michel Arrigoni, Alain Nême, Hugo Groeneveld and Sjoerd Van Der Veen
Sensors 2021, 21(13), 4429; https://0-doi-org.brum.beds.ac.uk/10.3390/s21134429 - 28 Jun 2021
Cited by 7 | Viewed by 2727
Abstract
High explosive hydro forming (HEHF) is a suitable technique for large metal plate forming. Manufacturing stages of such a part requires an adapted design of explosive charge configurations to define the mechanical loading exerted on the part. This mechanical loading remains challenging to [...] Read more.
High explosive hydro forming (HEHF) is a suitable technique for large metal plate forming. Manufacturing stages of such a part requires an adapted design of explosive charge configurations to define the mechanical loading exerted on the part. This mechanical loading remains challenging to be experimentally determined but necessary for predictive numerical simulation in the design of parts to form. Providing that the actual mechanical impulse would allow the neglecting of the modelling of the detonation stage, this considerably increases the computational time. The present work proposes an experimental method for obtaining the exerted mechanical loading by HEHF on the part to form. It relies on the development of low-cost sensor based on a polyvinyliden fluorid (PVDF) gauge. In addition to it, an analytical approach based on shock physics is proposed for the sensor signal interpretation. The method considers the multi-layer aspect of the sensor and its intrusiveness with respect to waves propagation. Measurements were repeated to assess their relevance and the reproducibility by using steel and aluminium anvils in HEHF. Numerical modelling in 2D plane geometry of the experiments was performed with two commercial hydrocodes. The comparison of mechanical impulses shows an agreement in terms of chronology but a noticeable difference in terms of amplitude, explained by mesh size and numerical diffusion. Full article
(This article belongs to the Special Issue Metrology of Shock Waves)
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