Results Of Quasi-static Analysis Research Articles

Approximate theoretical analysis of gas penetration in metal micro spallation

After high pressure shock, the shock wave in the metal is unloaded at the metal-gas interface, and micro spallation occurs when the metal melts. When the micro spallation develops to a certain extent, the high pressure gas penetrates the zero pressure vacuum gap between the metal melt droplets. In this paper, the phenomenon of gas penetrating metal micro spallation zone is analyzed theoretically. Based on the regular hexahedron periodic arrangement of metal droplets, the calculation formulas of the maximum penetration depth, the sealing time of the penetration channel and the maximum mass of the gas penetrating the metal micro spallation zone are given through theoretical analysis under the quasi-static and semi-dynamic conditions. The quasi-static process is considered to be the gas penetration process that can be approximated as the escape process of gas into the vacuum, and the gap in the metal micro spallation zone will be filled with gas. The semi-dynamic analysis is based on two basic assumptions: one is the equal droplet size and spacing in the micro spallation zone and the other is the critical sealing condition of gas penetration. In the process of semi-dynamic analysis it is demonstrated that the initial critical sealing distance is independent of the shape factor of the droplet single control volume. The semi-dynamic analysis can give various critical sealing information when the gas stops penetrating the metal micro spallation zone. The results of quasi-static analysis can be used as the upper limit of gas penetration, and the semi-dynamic analysis results can be used as the lower limit of gas penetration. From the sensitivity analysis, it can be seen that the change law of physical phenomena given by theoretical analysis accords with the basic physical understanding of the problem. Through this study, the upper and lower limit of the mixed state of gas penetrating the metal micro spallation zone can be estimated, which can provide more accurate initial metal-gas mixed state for subsequent research of the evolution of mixed state. The theoretical analyses given in this paper are based on a lot of uncertain assumptions, and the in-depth study of this phenomenon is still needed based on the law summary and mutual confirmation of experiment and simulation.

New and accurate synthesis formulas for open supported coplanar waveguides

AbstractIn this article, new and accurate synthesis formulas to compute the physical dimensions of open supported coplanar waveguides (OS‐CPWs) are presented. The synthesis formulas are obtained with the use of differential evolution (DE) and particle swarm optimization (PSO) algorithms. They are useful for the computer‐aided design of OS‐CPWs. The average percentage errors of the synthesis formulas obtained by using DE and PSO algorithms are computed to be 1.26% and 1.67%, respectively, for 4560 OS‐CPW samples having different electrical parameters and physical dimensions, as compared with the results of quasi‐static analysis. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 262–269, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24908

ACCURATE SYNTHESIS FORMULAS OBTAINED BY USING A DIFFERENTIAL EVOLUTION ALGORITHM FOR CONDUCTOR-BACKED COPLANAR WAVEGUIDES

In this paper, accurate synthesis formulas obtained by using a difierential evolution (DE) algorithm for conductor-backed coplanar waveguides (CBCPWs) are presented. The synthesis formulas are useful to microwave engineers for accurately calculating the physical dimensions of CBCPWs. The results of the synthesis formulas are compared with the theoretical and experimental results available in the literature. A full-wave electromagnetic simulator IE3D and experimental results are obtained in this work. The average percentage error of the synthesis formulas obtained by using DE algorithm is computed as 0.67% for 1086 CBCPW samples having difierent electrical parameters and physical dimensions, as compared with the results of quasi-static analysis.

New and Accurate Synthesis Formulas for Asymmetric Coplanar Stripline with an Infinitely Wide Strip

New and accurate synthesis formulas for the asymmetric coplanar stripline with an infinitely wide strip (ACPS-IWS) are presented. They are obtained by using a differential evolution algorithm (DEA) and particle swarm optimization (PSO) algorithm, and are useful to microwave engineers for accurately computing the physical dimensions of ACPS-IWS. The average percentage errors of the synthesis formulas found by using DEA and PSO are calculated to be 0.85% and 1.62%, respectively, for 4913 ACPS-IWS samples having different electrical parameters and physical dimensions, as compared with the results of quasi-static analysis.

Synthesis Formulas for Multilayer Homogeneous Coupling Structure with Ground Shielding

This paper presents new and accurate synthesis formulas for the multilayer homogeneous coupling structure with ground shielding (MHCS-WGS). The synthesis formulas are obtained by means of a differential evolution algorithm (DEA), and are useful to microwave engineers for accurately calculating the physical dimensions of MHCS-WGS. The average percentage error is calculated to be 0.8% for 13614 MHCS-WGS samples having different electrical parameters and physical dimensions, as compared with the results of quasi-static analysis.

Very accurate and simple CAD models based on neural networks for coplanar waveguide synthesis

Very accurate and simple neural models for coplanar waveguide (CPW) synthesis are proposed. The results obtained from these neural models are compared with the results of quasi-static analysis, the other synthesis formulas, and other experimental works. The accuracy of the neural models is found to be better than 0.4% for 11,206 CPW samples. © 2005 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2005.

Artificial Neural Network Models for Coplanar Stripline Synthesis

This paper presents an Artificial Neural Network based coplanar stripline (CPS) synthesis models suitable for microwave Computer-aided design (CAD) applications. The synthesis models were developed by training feedforward neural network with the numerical results of quasi-static analysis. The correlation between the results of developed models and the expected results are greater than 0.999920 for all modeled parameters. The proposed approach is capable of providing accurate CAD models for synthesis of microwave and millimeter-wave components for which accurate analysis models are available whereas accurate synthesis models are not available.

CAD Models for Coplanar Waveguide Synthesis using Artificial Neural Network

This paper presents Artificial neural network based synthesis models for Coplanar waveguide (CPW) suitable for Computer aided-design (CAD) applications. The CPW synthesis models were basically developed by training the neural network with the numerical results of quasi-static analysis. The developed models have been validated and the correlations between the results of developed models and quasi-static analysis results are greater than 0.999938 for each modeled parameters. The results presented indicate that the developed models retain the accuracy of the quasi-static analysis. The proposed approach is capable of providing accurate and efficient CAD models for synthesis of microwave and millimeter-wave components for which accurate analysis results are available whereas synthesis models are not available or are not accurate over the desired range of operation.