scholarly journals Exploding wire energy absorption dynamics at slow current rates

2016 ◽  
Vol 35 (1) ◽  
pp. 26-32 ◽  
Author(s):  
G. Rodríguez Prieto ◽  
L. Bilbao ◽  
M. Milanese
Keyword(s):  
Energy Absorption ◽  
Optical Sensors ◽  
Electrical Energy ◽  
Electrical Current ◽  
Initial Kinetic Energy ◽  
Metallic Wire ◽  
Exploding Wire ◽  
Initial Voltage ◽  
The Wire ◽  
Wire System

AbstractAbsorption of electrical energy provided to a metal wire in an exploding wire system is thought to be terminated or greatly diminished when the plasma is formed, after the joule heating of the metallic wire by the electrical current. Accordingly, it is common to account for the electrical energy delivered to the wire that the integration of current and voltage signals is halted when the voltage peak changes its slope. Usually, this moment is synchronized with the plasma appearance, as detected by optical sensors. In this work, experimental evidence of a two-step electrical energy absorption in an exploding wire surrounded by atmospheric air is presented. During the first step of the energy absorption the plasma is not formed, indicating that the delivered energy is not enough for ionizing the wire, giving place to a dark pause that lasts until a second energy absorption produces a plasma. The delay between the two steps can reach ≈2.2 µs for copper wires of 50 µm diameter charged at an initial voltage of 10 kV. Experimental investigation of variation of the delay between the two steps with different metals, charging voltages, and wire diameters are presented. A relation of the current density with the initial kinetic energy of the plasma and the electrical current rate is devised as a possible explanation of the observed phenomena.

scholarly journals Temporal distribution of the electrical energy on an exploding wire

2016 ◽  
Vol 34 (2) ◽  
pp. 263-269 ◽  
Author(s):  
Gonzalo Rodríguez Prieto ◽  
Luis Bilbao ◽  
Malena Milanese
Keyword(s):  
Energy Transfer ◽  
Temporal Distribution ◽  
Electrical Energy ◽  
Radial Expansion ◽  
Plasma Expansion ◽  
Metallic Wire ◽  
Plasma Dynamics ◽  
Exploding Wire ◽  
Lower Limits ◽  
Wire System

AbstractAn exploding wire system has been experimentally studied by the observation of its plasma dynamics and the electrical energy delivered by the supporting circuit to the metallic wire. Plasma radial expansion has been obtained from visible light streak images, meanwhile electrical energy transfer dynamics was derived from the analysis of voltage and current traces of the exploding wire circuit. In these measurements, a significant portion of the electrical energy has been transferred to the exploding wire circuit during the plasma expansion, and lower limits for the resistivity during the plasma expansion confirm the existence of a central liquid or solid metallic core in addition to the expanding plasma.

scholarly journals ‎‏FINDING PERCENTAGE OF BREAKDOWN STIMULATION OF ALUMINUM WIRES THAT OPERATES IN A CORROSIVE MEDIUM

2022 ◽  
Vol 26 (1) ◽  
pp. 87-94
Author(s):  
Mohammed Abdulateef Ahmed ◽  
Keyword(s):  
Tensile Stress ◽  
Electrical Energy ◽  
Electrical Current ◽  
Mechanical Resistance ◽  
Corrosive Environment ◽  
Aluminum Wire ◽  
Different Temperatures ◽  
Static Tensile ◽  
The Wire ◽  
Static Tensile Stress

The study of the duration of mechanical resistance to static tensile stress (withstand time) for an aluminum wire that being suffers from the corrosion effect stimulated by stray currents at different temperatures. Test device was designed and produced locally "in advance" in accordance with the specification (ASTM G103 - 97) to create static tensile stress of (1 N) on an aluminum wire of type ASTM (B231/B231M) with particular dimensions and utilized in the transmission of electrical energy, and when the wire is surrounded by a corrosive environment (NaCl solution) (3.5 % NaCl) at three different temperatures (25, 50, and 75 ° C) without any external electrical current causing corrosion; this symbolizes stray currents. Then compare the findings of that example to the results of the same wire's withstand time in the presence of an external electrical current generated by corrosion of type (D.C) by (5V & 3A). Following that, the resulting diagrams were analyzed, and it was discovered that the wire resistivity time (without the existence of stray currents and at a temperature of 25 ° C) completed (17 days), which is the longest duration of endure, and the lowest time of resistivity or resistance period (in the existence of an external electric current) is (18 hr.).Impact of (stray currents) at (75 ° C), and this is an indicator of the stray currents with corrosive environment temperatures on the resistance period (withstand duration) in the existence of static stress. The total stimulation increase is 1.9% between corrosion at 75°C and 25°C.

Optimization of a Treatment System of Wastewater Streams for Electrochemical Cr(VI) Reduction: Selective versus Centralized Treatment

2018 ◽  
Vol 16 (11) ◽  
Author(s):  
Adrián López-Yañez ◽  
Jorge Ramirez-Muñoz ◽  
Alejandro Alonso ◽  
Luis G. Cota ◽  
Jhonny Pérez Montiel
Keyword(s):  
Hexavalent Chromium ◽  
Minimum Cost ◽  
Electrical Energy ◽  
Electrical Current ◽  
Electrochemical Process ◽  
Effluent Treatment ◽  
Treated Wastewater ◽  
Total Annual Cost ◽  
Optimal Solutions ◽  
Selective Treatment

Abstract The problem of the optimization of selective treatment systems of wastewater streams contaminated with hexavalent chromium [Cr(VI)] is investigated. In order to comply with the Mexican environmental norm of Cr(VI) for treated wastewater streams at minimum cost, a nonlinear programming (NLP) model for the electrochemical reduction of hexavalent chromium to trivalent chromium was developed. The model incorporates a variable reaction rate, which is a function of the Cr(VI) concentration and the electrical current density of the electrochemical process. For this purpose, a basic superstructure of the effluent treatment is proposed. The superstructure is composed of three continuous electrochemical reactors without recirculation, and it may produce either a series and/or parallel design topology. The NLP model was used to minimize the objective function, defined as the total annual cost (TAC), which includes the capital cost of each electrochemical reactor, the electrical energy cost and the cost of the treatment of the wastewater streams. In order to investigate the solution set of the proposed NLP model, i. e., to improve the possibilities of obtaining optimum solutions based on economic criteria, a multi-start algorithm was implemented. Two example problems are used to show the versatility of the model and different local optimal solutions were obtained for each case study. The results show that a selective treatment of wastewater streams based on the search of local optimal solutions yields significant savings with respect to a centralized treatment design.

scholarly journals Mechanical Behavior of Entangled Metallic Wire Materials under Quasi-Static and Impact Loading

Materials ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3392 ◽  
Author(s):  
Yiwan Wu ◽  
Lei Jiang ◽  
Hongbai Bai ◽  
Chunhong Lu ◽  
Shangzhou Li
Keyword(s):  
Energy Absorption ◽  
Impact Loading ◽  
Absorption Rate ◽  
Maximum Load ◽  
Low Velocity Impact ◽  
Low Velocity ◽  
Metallic Wire ◽  
Maximum Deformation ◽  
Air Damping ◽  
Stiffness And Damping

In this paper, the stiffness and damping property of entangled metallic wire materials (EMWM) under quasi-static and low-velocity impact loading were investigated. The results reveal that the maximum deformation of the EMWM mainly depends on the maximum load it bears, and that air damping is the main way to dissipate impact energy. The EMWM can absorb more energy (energy absorption rate is over 60%) under impact conditions. The EMWM has excellent characteristics of repetitive energy absorption.

Interaction Between Solid Copper Jets and Powerful Electrical Current Pulses

2010 ◽  
Vol 78 (2) ◽  
Author(s):  
Patrik Appelgren ◽  
Torgny E. Carlsson ◽  
Andreas Helte ◽  
Tomas Hurtig ◽  
Anders Larsson ◽  
...  
Keyword(s):  
Current Pulse ◽  
Current Density ◽  
Energy Deposition ◽  
Current Flow ◽  
Contact Region ◽  
Electrical Energy ◽  
Electrical Current ◽  
Separation Distance ◽  
Flow Through ◽  
Solid Copper

The interaction between a solid copper jet and an electric current pulse is studied. Copper jets that were created by a shaped-charge device were passed through an electrode configuration consisting of two aluminum plates with a separation distance of 150 mm. The electrodes were connected to a pulsed-power supply delivering a current pulse with amplitudes up to 250 kA. The current and voltages were measured, providing data on energy deposition in the jet and electrode contact region, and flash X-ray diagnostics were used to depict the jet during and after electrification. The shape of, and the velocity distributions along, the jet has been used to estimate the correlation between the jet mass flow through the electrodes and the electrical energy deposition. On average, 2.8 kJ/g was deposited in the jet and electrode region, which is sufficient to bring the jet up to the boiling point. A model based on the assumption of a homogenous current flow through the jet between the electrodes underestimates the energy deposition and the jet resistance by a factor 5 compared with the experiments, indicating a more complex current flow through the jet. The experimental results indicate the following mechanism for the enhancement of jet breakup. When electrified, the natural-formed necks in the jet are subjected to a higher current density compared with other parts of the jet. The higher current density results in a stronger heating and a stronger magnetic pinch force. Eventually, the jet material in the neck is evaporated and explodes electrically, resulting in a radial ejection of vaporized jet material.

Flexible Valveless Pump for Bio Applications

2019 ◽  
Author(s):  
Masoud Naghdi ◽  
Farhad Farzbod ◽  
Paul M. Goggans
Keyword(s):  
Liquid Metal ◽  
Lorentz Force ◽  
Permanent Magnets ◽  
Mechanical Energy ◽  
Electrical Energy ◽  
Electrical Current ◽  
Electromechanical Actuators ◽  
Valveless Pump ◽  
Metal Wires ◽  
Lorentz Force Law

Abstract In electromechanical actuators Lorentz force law is used to convert electrical energy into rotational or linear mechanical energy. In these conventional electromechanical actuators, rigid wires conducts the electrical current and as such the types of motion generated by these actuators are limited. Recent advances in liquid metal alloys permit designing electrical wires that are stretchable. These flexible wires have been used to fabricate various flexible connections, sensors and antennas. However, there have been very little efforts to use these stretchable liquid metal wires as actuators. Building upon our previous work in this area, we have made a flexible pump which can be used in bio applications. In this design we placed a flexible polymeric substrate filled by liquid metal Galinstan between two permanent magnets. Since the pump should convey the biological cells suspended along the fluid flow, utilizing check valves may increase the risk of clog in the inlet or outlet. Therefore, our design is based on the nozzle/diffuser concept. This new pump can be considered as a peristaltic and valve-less mechanical pumps which utilizes the Lorentz force law as the actuating mechanism.

scholarly journals Analog tachometer as an indicator motorcycle machine wearing based on moving coil

2018 ◽  
Vol 43 ◽  
pp. 01004
Author(s):  
Dhanis Woro Fittrin Selo Nur Giyatno ◽  
Tommy Richard Orlando ◽  
Nining Supriatin
Keyword(s):  
Control Unit ◽  
Electrical Energy ◽  
Electrical Current ◽  
Maintenance Cost ◽  
Current Sensing ◽  
Variable Resistor ◽  
Rotary Machine ◽  
System A ◽  
Machine Reliability ◽  
Electronic Instrumentation

As an increasing highly mobility and high traffic, the necessary of motorcycle is highly increasing. The condition makes user ride motorcycle with highly speed in highly frequency. Then, these conditions make motorcycle machine reliability is highly decreasing. Finally, it made machine is run to damage and maintenance cost to be high. Analog tachometer is an electronic instrumentation that proposed to solve these problems. Actually, instrumentation system of tachometer is an electromechanical system. A wire in a control unit is embedded into shaft of crank. Then, magnet in control unit will convert rotary machine energy into electrical energy with d’Arsonval meter. Current sensor and small variable resistor are the kind of sensor that are used in tachometer. Small variable resistor is used for tuning and recalibration. Utilization small variable resistor in tachometer circuit is make calibration and recalibration current sensing of electrical current that rectified by diode. Tachometer for counting rotation per minute (RPM) motorcycle machine is built up. The tachometer has capability to count RPM motorcycle machine 1,000 – 13.000 RPM. The range is reliable as an indicator for user to minimize motorcycle machine wearing.

Impact Resistance and Energy Absorption of Functionally Graded Cellular Structures

2011 ◽  
Vol 69 ◽  
pp. 73-78 ◽  
Author(s):  
Xiao Kai Wang ◽  
Zhi Jun Zheng ◽  
Ji Lin Yu ◽  
Chang Feng Wang
Keyword(s):  
Energy Absorption ◽  
Impact Resistance ◽  
Functionally Graded ◽  
Cellular Structures ◽  
Stress Wave Propagation ◽  
Initial Kinetic Energy ◽  
Gradual Change ◽  
Two Dimensional ◽  
The One ◽  
The Impact

The dynamic response of functionally graded cellular structures subjected to impact of a finite mass was investigated in this paper. Compared to a cellular structure with a uniform cell size, the one with gradually changing cell sizes may improve many properties. Based on the two-dimensional random Voronoi technique, a two-dimensional topological configuration of cellular structures with a linear density-gradient in one direction was constructed by changing the cell sizes. The finite element method using ABAQUS/Explicit code was employed to investigate the energy absorption and the influence of gradient on stress wave propagation. Results show that functionally graded cellular structures studied are superior in energy absorption to the equivalent uniform cellular structures under low initial kinetic energy impacts, and the performance of such structures can be significantly improved when the density difference is enlarged. The stress levels at the impact and support ends may be reduced by introducing a gradual change of density in cellular structures when the initial impact velocity is low.

Preliminary Results of Stress Recovery of Constrained NiTi SMA Wire for Aerospace Applications

2010 ◽  
Vol 643 ◽  
pp. 15-18
Author(s):  
Júlio Cesar Santos ◽  
Antunes Andre Da Silva ◽  
Afonso Paulo Monteiro Pinheiro ◽  
Leonardo Kyo Kabayama ◽  
Odair Doná Rigo ◽  
...  
Keyword(s):  
Shape Recovery ◽  
Electrical Current ◽  
Recovery Stress ◽  
Wire Electrode ◽  
Recovery Effect ◽  
Ignition System ◽  
Gas Leakage ◽  
Aerospace Applications ◽  
Niti Sma ◽  
The Wire

The rocket propellant ignition system uses electro-explosive device actuated by wire electrode. Those wires are usually made by Fe-Ni based alloy with controlled thermal expansion inserted into a ceramic feed-through and are connected to thin resistive wire which is heated through the passage of an electrical current for propellant ignition. The contact between ceramic feed-through and wires should be reliable since sometimes it could fail. A novel alternative process is to use SMA wires taking into account the shape recovery effect constraining the wire inside the feed-through. The recovery stress of 326 MPa for 4% pre-strain should be enough to constrain the wire inside the feed-trough avoiding the gas leakage.

Sign in / Sign up

Export Citation Format

Share Document