The Effect of the Design of Surgical Electrodes On the Formation of Sparking Enhanced Burns

2021 ◽  
Author(s):  
Marija Radmilovic-Radjenovic ◽  
Dimitrije Radjenovic ◽  
Branislav Radjenovic
Keyword(s):  
Experimental Data ◽  
Computer Modeling ◽  
Direct Current ◽  
Fire Risk ◽  
Experimental Methods ◽  
Standard Procedures ◽  
Surgical Field ◽  
Simulation Results ◽  
Comsol Simulation ◽  
Simulation Package

Abstract Electrocautery is a safe and effective method of hemostasis during cutaneous surgery. Despite the unquestionable benefits, electrocautery sparks in the surgical field represent a significant fire risk that can be eliminated by clarifying the causation and conditions of their development. Apart from the experimental methods, computer modeling is proven to be an effective approach to improve the performance of electrocautery. This paper is dealing with the design of electrodes to prevent burns during standard procedures. Simulations were carried out by using the COMSOL simulation package for various electrode configurations (cylinder-cylinder, sphere-sphere, sphere-cylinder, and cylinder-sphere) representing shapes of surgical electrodes. The primary goal was to determine the location where sparking starts. The obtained simulation results agree well with the experimental data taken from the literature supporting that the sparking formation is strongly affected by the electrode configuration. It was found that sparking occurs most easily when both electrodes are cylindrical. Also, the sparking mechanism depends on electrical asymmetry that results in undesirable direct current burns. Results presented here can be used to establish practices for the safe use of the electrocautery devices and to prevent injury to patients and staff.

Effect of Ambient Temperature Zinc Oxide Surge Arrester Condition Monitoring

2014 ◽  
Vol 554 ◽  
pp. 573-577 ◽  
Author(s):  
Zulkurnain Abdul-Maleka ◽  
Amir Hesam Khavari ◽  
Nabipour Afrouzi Hadi ◽  
Saeed Vahabi-Mashak
Keyword(s):  
Experimental Data ◽  
Zinc Oxide ◽  
Surface Temperature ◽  
Ambient Temperature ◽  
Simulation Analysis ◽  
Simulation Software ◽  
Surge Arresters ◽  
Simulation Results ◽  
Comsol Simulation ◽  
The Relationship

Various methods have been developed to monitor surge arrester condition and predict the probable interruption which can be caused by the failure of surge arresters. This paper aims to carry out experimental and simulation work to find the relationship between the aging level, arrester surface temperature and ambient temperature. COMSOL simulation software was used for the modeling of 120kV rated gapless ZnO surge arresters. It is observed from both the simulation analysis and experimental data that the leakage current and temperature increase as a consequence of an increase in the applied voltage across the arrester. The thermal profile of the ZnO surge arrester changes depending on the aging level and the ambient temperature. The surface temperature simulation results compare well with the experimental results, for the case of varying aging levels.

BEHAVIORAL MODEL OF A LINEAR VOLTAGE STABILIZER IN THE SPICE LANGUAGE

2019 ◽  
Author(s):  
Aleksey Malahanov
Keyword(s):  
Experimental Data ◽  
Behavioral Model ◽  
Voltage Stabilizer ◽  
Static Mode ◽  
Technical Description ◽  
Simulation Results ◽  
Chip Manufacturer ◽  
Linear Voltage

A variant of the implementation of the behavioral model of a linear voltage stabilizer in the Spice language is presented. The results of modeling in static mode are presented. The simulation results are compared with experimental data and technical description of the chip manufacturer.

scholarly journals Realization of a fractional-order RLC circuit via constant phase element

2021 ◽  
Author(s):  
Riccardo Caponetto ◽  
Salvatore Graziani ◽  
Emanuele Murgano
Keyword(s):  
Experimental Data ◽  
Carbon Black ◽  
Fractional Order ◽  
Constant Phase Element ◽  
Polymeric Matrix ◽  
Fractional Order Systems ◽  
New Device ◽  
Rlc Circuit ◽  
Simulation Results

AbstractIn the paper, a fractional-order RLC circuit is presented. The circuit is realized by using a fractional-order capacitor. This is realized by using carbon black dispersed in a polymeric matrix. Simulation results are compared with the experimental data, confirming the suitability of applying this new device in the circuital implementation of fractional-order systems.

scholarly journals Investigation of the Thickness Differential on the Formability of Aluminum Tailor Welded Blanks

Metals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 875
Author(s):  
Jie Wu ◽  
Yuri Hovanski ◽  
Michael Miles
Keyword(s):  
Experimental Data ◽  
Finite Element ◽  
Numerical Model ◽  
Plastic Strain ◽  
Finite Element Model ◽  
Equivalent Plastic Strain ◽  
Element Model ◽  
Dome Height ◽  
Tailor Welded Blanks ◽  
Simulation Results

A finite element model is proposed to investigate the effect of thickness differential on Limiting Dome Height (LDH) testing of aluminum tailor-welded blanks. The numerical model is validated via comparison of the equivalent plastic strain and displacement distribution between the simulation results and the experimental data. The normalized equivalent plastic strain and normalized LDH values are proposed as a means of quantifying the influence of thickness differential for a variety of different ratios. Increasing thickness differential was found to decrease the normalized equivalent plastic strain and normalized LDH values, this providing an evaluation of blank formability.

scholarly journals Verification of electric steel punching simulation results using microhardness

2021 ◽  
Author(s):  
Sampsa Vili Antero Laakso ◽  
Ugur Aydin ◽  
Peter Krajnik
Keyword(s):  
Plastic Deformation ◽  
High Speed ◽  
Steel Sheet ◽  
Electrical Steel ◽  
High Speed Steel ◽  
Experimental Methods ◽  
Fem Simulations ◽  
Iron Losses ◽  
Simulation Results ◽  
Electrical Steel Sheet

AbstractOne of the most dominant manufacturing methods in the production of electromechanical devices from sheet metal is punching. In punching, the material undergoes plastic deformation and finally fracture. Punching of an electrical steel sheet causes plastic deformation on the edges of the part, which affects the magnetic properties of the material, i.e., increases iron losses in the material, which in turn has a negative effect on the performance of the electromagnetic devices in the final product. Therefore, punching-induced iron losses decrease the energy efficiency of the device. FEM simulations of punching have shown significantly increased plastic deformation on the workpiece edges with increasing tool wear. In order to identify the critical tool wear, after which the iron losses have increased beyond acceptable limits, the simulation results must be verified with experimental methods. The acceptable limits are pushed further in the standards by the International Electrotechnical Commission (IEC). The new standard (IEC TS 60034-30-2:2016) has much stricter limits regarding the energy efficiency of electromechanical machines, with an IE5 class efficiency that exceeds the previous IE4 class (IEC 60034-30-1:2014) requirements by 30%. The simulations are done using Scientific Forming Technologies Corporation Deform, a finite element software for material processing simulations. The electrical steel used is M400-50A, and the tool material is Vanadis 23, a powder-based high-speed steel. Vanadis 23 is a high alloyed powder metallurgical high-speed steel with a high abrasive wear resistance and a high compressive strength. It is suitable for cold work processing like punching. In the existing literature, FEM simulations and experimental methods have been incorporated for investigating the edge deformation properties of sheared surfaces, but there is a research gap in verifying the simulation results with the experimental methods. In this paper, FEM simulation of the punching process is verified using an electrical steel sheet from real production environment and measuring the deformation of the edges using microhardness measurements. The simulations show high plastic deformation 50 μm into the workpiece edge, a result that is shown to be in good agreement with the experimental results.

Wear of a Tool in Double-Disk Lapping of Silicon Wafers

2010 ◽  
Author(s):  
Adam Barylski ◽  
Mariusz Deja
Keyword(s):  
Experimental Data ◽  
Integrated Circuits ◽  
Tool Wear ◽  
Silicon Wafers ◽  
Silicon Ingot ◽  
Proposed Model ◽  
Tool Wear Prediction ◽  
Simulation Results ◽  
High Degree ◽  
Kinematical Parameters

Silicon wafers are the most widely used substrates for fabricating integrated circuits. A sequence of processes is needed to turn a silicon ingot into silicon wafers. One of the processes is flattening by lapping or by grinding to achieve a high degree of flatness and parallelism of the wafer [1, 2, 3]. Lapping can effectively remove or reduce the waviness induced by preceding operations [2, 4]. The main aim of this paper is to compare the simulation results with lapping experimental data obtained from the Polish producer of silicon wafers, the company Cemat Silicon from Warsaw (www.cematsil.com). Proposed model is going to be implemented by this company for the tool wear prediction. Proposed model can be applied for lapping or grinding with single or double-disc lapping kinematics [5, 6, 7]. Geometrical and kinematical relations with the simulations are presented in the work. Generated results for given workpiece diameter and for different kinematical parameters are studied using models programmed in the Matlab environment.

Experimental Methodologies: Two Case Studies Investigating the Syntax- Discourse Interface

2013 ◽  
Vol 6 (1) ◽  
Author(s):  
Timothy Gupton ◽  
Tania Leal Méndez
Keyword(s):  
Experimental Data ◽  
Quantitative Data ◽  
Native Speaker ◽  
Experimental Methods ◽  
Experimental Investigations ◽  
Experimenter Bias ◽  
Current Article ◽  
Theoretical Syntax ◽  
Discourse Interface ◽  
L1 And L2

AbstractThe current article examines two experimental investigations of the syntaxdiscourse interface, which address theoretical questions in different ways: the first is an L1 investigation of Galician speakers in Gupton (2010) and the second is a dual investigation of L1 and L2 Spanish reported on in Leal Méndez & Slabakova (2011). These investigations gathered quantitative data via psycholinguistic tasks with accompanying audio utilizing the WebSurveyor platform. They involved counterbalanced designs and were followed by statistical analysis. While acknowledging that experimental data does not have primacy over intuitive data, the authors endorse the use of experimental methods of data elicitation (such as the ones already used in generative SLA research) in theoretical syntax in order to avoid experimenter bias and to get a more complete picture of native speaker intuition and competencies.

The penetration and ricochet of ogive-nosed rigid projectiles obliquely impacting metallic targets

2021 ◽  
pp. 204141962110377
Author(s):  
Yaniv Vayig ◽  
Zvi Rosenberg
Keyword(s):  
Experimental Data ◽  
Numerical Simulations ◽  
Dynamic Pressure ◽  
Oblique Impacts ◽  
Simulation Results ◽  
The Impact ◽  
Penetration Depths ◽  
Resistance To Penetration ◽  
Good Agreement

A large number of 3D numerical simulations were performed in order to follow the trajectory changes of rigid CRH3 ogive-nosed projectiles, impacting semi-infinite metallic targets at various obliquities. These trajectory changes are shown to be related to the threshold ricochet angles of the projectile/target pairs. These threshold angles are the impact obliquities where the projectiles end up moving in a path parallel to the target’s face. They were found to depend on a non-dimensional entity which is equal to the ratio between the target’s resistance to penetration and the dynamic pressure exerted by the projectile upon impact. Good agreement was obtained by comparing simulation results for these trajectory changes with experimental data from several published works. In addition, numerically-based relations were derived for the penetration depths of these ogive-nosed projectiles at oblique impacts, which are shown to agree with the simulation results.

scholarly journals Development of a Novel Hybrid Unified Viscoplastic Constitutive Model

2015 ◽  
Author(s):  
Luis A. Varela J. ◽  
Calvin M. Stewart
Keyword(s):  
Experimental Data ◽  
Stainless Steel ◽  
Hybrid Model ◽  
Material Constant ◽  
Inelastic Behavior ◽  
Hastelloy X ◽  
Material Constants ◽  
Stainless Steel 304 ◽  
Simulation Results ◽  
Optimal Material

Hastelloy X and stainless steel 304 are alloys widely used in industrial gas turbines components, petrochemical industry and energy generation applications; In the Pressure Vessel and Piping (PVP) industries they are used in nuclear and chemical reactors, pipes and valves applications. Hastelloy X and stainless steel 304 are favored for these types of applications where elevated temperatures are preferred for better systems’ efficiencies; they are favored due to its high strength and corrosion resistance at high temperature levels. A common characteristic of these alloys, is its rate-dependent mechanical behavior which difficult the prediction of the material response for design and simulation purposes. Therefore, a precise unified viscoplastic model capable to describe Hastelloy X and stainless steel 304 behaviors under a variety of loading conditions at high temperatures is needed to allow a better and less conservative design of components. Numerous classical unified viscoplastic models have been proposed in literature, to predict the inelastic behavior of metals under extreme environments. Based on Miller and Walker classical unified constitutive models a novel hybrid unified viscoplastic constitutive model is introduced in the present work, to describe the inelastic behavior caused by creep and fatigue effects at high temperature. The presented hybrid model consists of the combination of the best aspects of Miller and Walker model constitutive equations, with the addition of a damage rate equation which provides a description of the damage evolution and rupture prediction capabilities for Hastelloy X and stainless steel 304. A detailed explanation on the meaning of each material constant is provided, along with its impact on the hybrid model behavior. Material constants were calculated using the recently developed Material Constant Heuristic Optimizer (MACHO) software, to ensure the use of the optimal material constants values. This software uses the simulated annealing algorithm to determine the optimal material constants in a global surface, by comparing numerical simulations to an extensive database of experimental data. To validate the capabilities of the proposed hybrid model, numerical simulation results are compared to a broad range of experimental data at different stress levels and strain amplitudes; besides the consideration of two alloys in the present work, would demonstrate the model’s capabilities and flexibility to model multiple alloys behavior. Finally a quantitative analysis is provided to determine the percentage error and coefficient of determination between the experimental data and numerical simulation results to estimate the efficiency of the proposed hybrid model.

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