IEEE Journal on Multiscale and Multiphysics Computational Techniques最新文献

{"title":"Fast Analysis of Broadband Electromagnetic Scattering Problems by Combining Hyper Basis Functions-Based MoM With Compressive Sensing","authors":"Zhonggen Wang;Chenwei Li;Yufa Sun;Wenyan Nie;Xuejun Zhang;Pan Wang","doi":"10.1109/JMMCT.2024.3355976","DOIUrl":"https://doi.org/10.1109/JMMCT.2024.3355976","url":null,"abstract":"The hyper basis functions (HBF)-based MoM has been proven to be an efficient numerical method to analyze broadband electromagnetic scattering problems. However, this method costs a lot of time to reconstruct the impedance matrix and reduced matrix at each frequency point. In order to solve the above problem, a novel method combining HBF-based MoM and compressive sensing (CS) has been proposed in this paper. The proposed method first applies the characteristic modes (CM) derived at the highest frequency point as the HBF for solving the scattering problems at lower frequency points, and performs sparse transform of the induced currents as the sparse basis for the CS framework. Then the measurement matrix is constructed using the method of uniformly extracting the impedance matrix by rows to obtain stable calculation results. Finally, according to the prior condition that a few CM are sufficient to characterize the surface currents approximately, the recovery algorithm is simplified least square method to reconstruct the current coefficients. Numerical simulation results show that it can significantly improve the efficiency of solving broadband electromagnetic problems compared with HBF-based MoM.","PeriodicalId":52176,"journal":{"name":"IEEE Journal on Multiscale and Multiphysics Computational Techniques","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139710586","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of Q-Factor for AM-SLM Cavity Based Resonators Using Surface Roughness Models","authors":"Qazi Mashaal Khan;Dan Kuylenstierna","doi":"10.1109/JMMCT.2024.3354489","DOIUrl":"https://doi.org/10.1109/JMMCT.2024.3354489","url":null,"abstract":"This research delves into losses of X-band cavity resonators manufactured using additive manufacturing-selective laser melting (AM-SLM) compared to the standard subtractive manufacturing milling technology. Measured losses are benchmarked in terms of resonator (quality) \u0000<inline-formula><tex-math>$Q$</tex-math></inline-formula>\u0000-factor. The measured data is further modelled using the Groiss and one-ball Huray models taking into account the implications of surface roughness and electrical conductivity. The unloaded \u0000<inline-formula><tex-math>$Q$</tex-math></inline-formula>\u0000-factor is derived from frequency-dependent scattering (\u0000<inline-formula><tex-math>$S$</tex-math></inline-formula>\u0000) parameters obtained from measurements and full-wave simulations. Surface roughness was found to impact the \u0000<inline-formula><tex-math>$Q$</tex-math></inline-formula>\u0000-factor significantly and the resonant frequency marginally. Cavities based on AM-SLM technology exhibit higher roughness compared to milling and lowers the \u0000<inline-formula><tex-math>$Q$</tex-math></inline-formula>\u0000-factor. A fusion of both manufacturing methods by milling AM-SLM cavity walls demonstrates an augmented \u0000<inline-formula><tex-math>$Q$</tex-math></inline-formula>\u0000-factor compared to a directly printed cavity. In the study it was also found that the Groiss model tends to overestimate the \u0000<inline-formula><tex-math>$Q$</tex-math></inline-formula>\u0000-factor owing to AM-SLM's rougher surface, while the one-ball Huray model furnishes precise projections by establishing a link between surface roughness and powder particles. Electrical conductivity's influence on \u0000<inline-formula><tex-math>$Q$</tex-math></inline-formula>\u0000-factor was also investigated, showing negligible impact with increased surface roughness. Further, side walls of the AM-SLM cavity were more susceptible to surface roughness, compared to the cavity front walls due to higher surface current density. This study underscores the significance of analyzing surface roughness and electrical conductivity in AM-SLM cavity resonators and highlights the suitability of the one-ball Huray model for accurate \u0000<inline-formula><tex-math>$Q$</tex-math></inline-formula>\u0000-factor prediction of microwave structures with rough surfaces.","PeriodicalId":52176,"journal":{"name":"IEEE Journal on Multiscale and Multiphysics Computational Techniques","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139654885","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Maxwell-Schrödinger Modeling of a Superconducting Qubit Coupled to a Transmission Line Network","authors":"Thomas E. Roth;Samuel T. Elkin","doi":"10.1109/JMMCT.2024.3349433","DOIUrl":"https://doi.org/10.1109/JMMCT.2024.3349433","url":null,"abstract":"In superconducting circuit quantum information technologies, classical microwave pulses are applied to control and measure the qubit states. Currently, the design of these microwave pulses uses simple theoretical or numerical models that do not account for the self-consistent interactions of how the qubit state modifies the applied microwave pulse. In this work, we present the formulation and finite element time domain discretization of a semiclassical Maxwell-Schrödinger method for describing these self-consistent dynamics for the case of a superconducting qubit capacitively coupled to a general transmission line network. We validate the proposed method by characterizing key effects related to common control and measurement approaches for transmon and fluxonium qubits in systems that are amenable to theoretical analysis. Our numerical results also highlight scenarios where including the self-consistent interactions is essential. By treating the microwaves classically, our method is substantially more efficient than fully-quantum methods for the many situations where the quantum statistics of the microwaves are not needed. Further, our approach does not require any reformulations when the transmission line system is modified. In the future, our method can be used to rapidly explore broader design spaces to search for more effective control and measurement protocols for superconducting qubits.","PeriodicalId":52176,"journal":{"name":"IEEE Journal on Multiscale and Multiphysics Computational Techniques","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139473800","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PIFON-EPT: MR-Based Electrical Property Tomography Using Physics-Informed Fourier Networks","authors":"Xinling Yu;José E. C. Serrallés;Ilias I. Giannakopoulos;Ziyue Liu;Luca Daniel;Riccardo Lattanzi;Zheng Zhang","doi":"10.1109/JMMCT.2023.3345798","DOIUrl":"https://doi.org/10.1109/JMMCT.2023.3345798","url":null,"abstract":"We propose Physics-Informed Fourier Networks for Electrical Properties (EP) Tomography (PIFON-EPT), a novel deep learning-based method for EP reconstruction using noisy and/or incomplete magnetic resonance (MR) measurements. Our approach leverages the Helmholtz equation to constrain two networks, responsible for the denoising and completion of the transmit fields, and the estimation of the object's EP, respectively. We embed a random Fourier features mapping into our networks to enable efficient learning of high-frequency details encoded in the transmit fields. We demonstrated the efficacy of PIFON-EPT through several simulated experiments at 3 and 7 T (T) MR imaging, and showed that our method can reconstruct physically consistent EP and transmit fields. Specifically, when only 20% of the noisy measured fields were used as inputs, PIFON-EPT reconstructed the EP of a phantom with \u0000<inline-formula><tex-math>$leq 5%$</tex-math></inline-formula>\u0000 error, and denoised and completed the measurements with \u0000<inline-formula><tex-math>$leq 1%$</tex-math></inline-formula>\u0000 error. Additionally, we adapted PIFON-EPT to solve the generalized Helmholtz equation that accounts for gradients of EP between inhomogeneities. This yielded improved results at interfaces between different materials without explicit knowledge of boundary conditions. PIFON-EPT is the first method that can simultaneously reconstruct EP and transmit fields from incomplete noisy MR measurements, providing new opportunities for EPT research.","PeriodicalId":52176,"journal":{"name":"IEEE Journal on Multiscale and Multiphysics Computational Techniques","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139399804","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced Thermodynamic Modeling of Converter Transformer Influenced by DC Bias","authors":"Suman Yadav;Gourav Kumar Suman;Ram Krishna Mehta","doi":"10.1109/JMMCT.2023.3334563","DOIUrl":"https://doi.org/10.1109/JMMCT.2023.3334563","url":null,"abstract":"DC bias in high-voltage DC transformers, arising from converter operations and DC transmission, poses significant challenges to their performance. The detrimental effects of DC bias primarily manifest in increased temperature, jeopardizing the safe operation of the transformers. This article presents a novel approach by extending the utilization of the Thermal Equivalent Circuit (TEC) to accurately predict temperatures at different elements of a converter transformer under DC bias conditions. Specifically designed for a 240 MVA converter transformer, the TEC incorporates capacitances and dynamic resistances as model parameters. Additionally, an electro-thermal finite element model is implemented to comprehensively analyze the transformer's behavior under varying levels of DC bias. To estimate the TEC parameters, a hybrid GWO-CS (Grey Wolf Optimization – Cuckoo Search) algorithm is employed based on measured values. Furthermore, the paper highlights the impact of DC bias on the converter transformer's life expectancy, considering the aging acceleration factor.","PeriodicalId":52176,"journal":{"name":"IEEE Journal on Multiscale and Multiphysics Computational Techniques","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138822201","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multiphysics Analysis of a High-Speed Eddy Current Brake","authors":"Sandeep Mohan Nayak;Mangal Kothari;Abhishek Sarkar;Soumya Ranjan Sahoo","doi":"10.1109/JMMCT.2023.3333386","DOIUrl":"https://doi.org/10.1109/JMMCT.2023.3333386","url":null,"abstract":"This paper presents the analytical-cum-numerical-based mathematical model for the multiphysics simulation of a high-speed unipolar axial eddy current brake (ECB). The operating principle and the necessary multiphysics simulation for an ECB are introduced. An analytical method is developed for high-speed ECB operation to search coarse parameters in the preliminary design technique. The model uses the behavior of the eddy currents on the plate during high-speed operation. A radial multiplier is incorporated to satisfy electromagnetic physics. The axisymmetric property of the disk reduces the disk geometry to an equivalent 2D domain where the estimated loss is defined. The ohmic loss from the analytical model is transferred to the numerical thermal model to evaluate temperature distribution. The convective heat transfer coefficient, which is a crucial variable in boundary conditions, is defined using the correlations between the Nusselt and Reynolds numbers. The steady-state heat diffusion equation is solved in the domain for three different speeds. The results show that the ohmic loss on the disk saturates and the temperature of the disk reduces during high-speed operations.","PeriodicalId":52176,"journal":{"name":"IEEE Journal on Multiscale and Multiphysics Computational Techniques","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138468117","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing Curl-Conforming Bases for Pyramid Cells","authors":"Roberto D. Graglia;Paolo Petrini","doi":"10.1109/JMMCT.2023.3333563","DOIUrl":"https://doi.org/10.1109/JMMCT.2023.3333563","url":null,"abstract":"Successful three-dimensional finite element codes for Maxwell's equations must include and deal with all four types of geometrical shapes: tetrahedra, bricks, prisms, and quadrangular-based pyramids. However, pyramidal elements have so far been used very rarely because the basis functions associated with them have complicated expression, are complex in derivation, and have never been comprehensively validated. We recently published a simpler procedure for constructing higher-order vector bases for pyramid elements, so here we fill a gap by discussing a whole set of test case results that not only validate our new curl-conforming bases for pyramids, but which enable validation of other codes that use pyramidal elements for finite element method applications. The solutions of the various test cases are obtained using either higher order elements or multipyramidal meshes or both. Furthermore, the results are always compared with the solutions obtained with classical tetrahedral meshes using higher order bases. This allows us to verify that purely pyramidal meshes and elements give numerical results of comparable accuracy to those obtained with multitetrahedral meshes that use elements of the same order, essentially requiring the same number of degrees of freedom. The various results provided here also show that higher order vector bases always guarantee a superior convergence of the numerical results as the number of degrees of freedom increases.","PeriodicalId":52176,"journal":{"name":"IEEE Journal on Multiscale and Multiphysics Computational Techniques","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10319679","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138435637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Algebraic and Fast Nested Construction Method for Generating Rank-Minimized ${mathcal H}^{2}$-Matrix for Solving Electrically Large Surface Integral Equations","authors":"Chang Yang;Dan Jiao","doi":"10.1109/JMMCT.2023.3326774","DOIUrl":"10.1109/JMMCT.2023.3326774","url":null,"abstract":"In this work, we develop a kernel-independent and purely algebraic method, Nested Construction Method, which can construct a rank-minimized \u0000<inline-formula><tex-math>${mathcal H}^{2}$</tex-math></inline-formula>\u0000-matrix with low complexity based on prescribed accuracy. The time cost of this method in generating each cluster basis and coupling matrix is of \u0000<inline-formula><tex-math>$O(k n log {n})$</tex-math></inline-formula>\u0000, while the memory consumption scales as \u0000<inline-formula><tex-math>$O(k^{2})$</tex-math></inline-formula>\u0000, where \u0000<inline-formula><tex-math>$k$</tex-math></inline-formula>\u0000 is the rank of the cluster basis, and \u0000<inline-formula><tex-math>$n$</tex-math></inline-formula>\u0000 is cluster size. The accuracy and efficiency of the proposed method are demonstrated by extensive numerical experiments. In addition to surface integral equations, the proposed algorithms can also be applied to solving other electrically large integral equations.","PeriodicalId":52176,"journal":{"name":"IEEE Journal on Multiscale and Multiphysics Computational Techniques","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135152772","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Excitation of Electromagnetic Field Inside Rotating Spherical Cavity","authors":"Daria E. Titova","doi":"10.1109/JMMCT.2023.3321123","DOIUrl":"https://doi.org/10.1109/JMMCT.2023.3321123","url":null,"abstract":"Rotating cavities are often used for rotation rate measurement. However, the representation of electromagnetic fields in rotating reference frames is based on simplifying assumptions and approximate solutions. In this article, problem of excitation of electromagnetic field inside a rotating spherical cavity resonator with arbitrary sources of currents and charges is formulated and solved rigorously. The solution is based on the covariant Maxwell's equations. Expressions for the electromagnetic field components are derived using electric and magnetic Debye potentials. Impedance boundary problem of electromagnetic field excitation in a rotating dielectric filled spherical cavity with finite conductivity metal walls is formulated and solved rigorously. In a special case of excitation of the cavity resonator with an elementary electric dipole, the frequency response and the quality factor of the resonator were calculated for different dielectric fillings and metals of the cavity walls. The obtained analytical solutions were verified for the special case of zero rotation rate compared with the simulation of the problem in CAD.","PeriodicalId":52176,"journal":{"name":"IEEE Journal on Multiscale and Multiphysics Computational Techniques","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68175802","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multiphysics Design Methodology for U-Band Temperature-Compensated Bandstop Filters","authors":"Chang Che;Yi Zeng;Ming Yu","doi":"10.1109/JMMCT.2023.3312756","DOIUrl":"https://doi.org/10.1109/JMMCT.2023.3312756","url":null,"abstract":"This article proposes a novel multiphysics design methodology for a U-band bandstop waveguide filter with temperature compensation (TC). A bimetal TC structure is first implemented to a bandstop filter in such high frequencies for working in a wide temperature range (−20 °C ∼ 70 °C) with little frequency drift. The synthesis and design of the bandstop filter are detailed. The proposed methodology mainly guides the design of the bimetal actuator from geometry, multiphysics, post-production and theoretical promotion. The geometric derivation for the bimetal reactions is elaborated and leads to a simplified equivalent model. Multiphysics analysis, including temperature, thermal stress, and electromagnetic field, is co-elaborated in the design process. Considering the fabrication errors, a post-production adjustment method for the TC structure is designed for practical use. Dimensionless formulae are introduced to provide general design guidelines and rules for filters with different dimensions and TC demands. Finally, a sixth-order temperature-compensated bandstop filter is manufactured and tested in temperature cycles. The measurements have validated the theoretical and simulation results.","PeriodicalId":52176,"journal":{"name":"IEEE Journal on Multiscale and Multiphysics Computational Techniques","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49962814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}