arXiv - PHYS - Applied Physics最新文献_第4页

Modelling of nucleate pool boiling on coated substrates using machine learning and empirical approaches 利用机器学习和经验方法建立涂层基底上核酸池沸腾模型

arXiv - PHYS - Applied Physics Pub Date : 2024-09-12 DOI: arxiv-2409.07811

Vijay Kuberan, Sateesh Gedupudi

{"title":"Modelling of nucleate pool boiling on coated substrates using machine learning and empirical approaches","authors":"Vijay Kuberan, Sateesh Gedupudi","doi":"arxiv-2409.07811","DOIUrl":"https://doi.org/arxiv-2409.07811","url":null,"abstract":"Surface modification results in substantial improvement in pool boiling heat\u0000transfer. Thin film-coated and porous-coated substrates, through different\u0000materials and techniques, significantly boost heat transfer through increased\u0000nucleation due to the presence of micro-cavities on the surface. The existing\u0000models and empirical correlations for boiling on these coated surfaces are\u0000constrained by specific operating conditions and parameter ranges and are hence\u0000limited by their prediction accuracy. This study focuses on developing an\u0000accurate and reliable Machine Learning (ML) model by effectively capturing the\u0000actual relationship between the influencing variables. Various ML algorithms\u0000have been evaluated on the thin film-coated and porous-coated datasets amassed\u0000from different studies. The CatBoost model demonstrated the best prediction\u0000accuracy after cross-validation and hyperparameter tuning. For the optimized\u0000CatBoost model, SHAP analysis has been carried out to identify the prominent\u0000influencing parameters and interpret the impact of parameter variation on the\u0000target variable. This model interpretation clearly justifies the decisions\u0000behind the model predictions, making it a robust model for the prediction of\u0000nucleate boiling Heat Transfer Coefficient (HTC) on coated surfaces. Finally,\u0000the existing empirical correlations have been assessed, and new correlations\u0000have been proposed to predict the HTC on these surfaces with the inclusion of\u0000influential parameters identified through SHAP interpretation. Keywords: Pool boiling, Thin film-coated, Porous-coated, Heat transfer\u0000coefficient, Machine learning, CatBoost, SHAP analysis","PeriodicalId":501083,"journal":{"name":"arXiv - PHYS - Applied Physics","volume":"13 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142177901","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}

引用次数: 0

Physical synchronization of soft self-oscillating limbs for fast and autonomous locomotion 软性自振荡肢体的物理同步，实现快速自主运动

arXiv - PHYS - Applied Physics Pub Date : 2024-09-11 DOI: arxiv-2409.07011

Alberto Comoretto, Harmannus A. H. Schomaker, Johannes T. B. Overvelde

引用次数: 0

Selective Actuation Enabled Multifunctional Magneto-mechanical Metamaterial for Programming Elastic Wave Propagation 用于编程弹性波传播的选择性致动多功能磁机械超材料

arXiv - PHYS - Applied Physics Pub Date : 2024-09-11 DOI: arxiv-2409.07635

Jay Sim, Shuai Wu, Sarah Hwang, Lu Lu, Ruike Renee Zhao

{"title":"Selective Actuation Enabled Multifunctional Magneto-mechanical Metamaterial for Programming Elastic Wave Propagation","authors":"Jay Sim, Shuai Wu, Sarah Hwang, Lu Lu, Ruike Renee Zhao","doi":"arxiv-2409.07635","DOIUrl":"https://doi.org/arxiv-2409.07635","url":null,"abstract":"Active metamaterials are a type of metamaterial with tunable properties\u0000enabled by structural reconfigurations. Existing active metamaterials often\u0000achieve only a limited number of structural reconfigurations upon the\u0000application of an external load across the entire structure. Here, we propose a\u0000selective actuation strategy for inhomogeneous deformations of\u0000magneto-mechanical metamaterials, which allows for the integration of multiple\u0000functionalities into a single metamaterial design. Central to this actuation\u0000strategy is that a magnetic field is applied to specific unit cells instead of\u0000the entire metamaterial, and the unit cell can transform between two\u0000geometrically distinct shapes, which exhibit very different mechanical\u0000responses to elastic wave excitations. Our numerical simulations and\u0000experiments demonstrate that the tunable response of the unit cell, coupled\u0000with inhomogeneous deformation achieved through selective actuation, unlocks\u0000multifunctional capabilities of magneto-mechanical metamaterials such as\u0000tunable elastic wave transmittance, elastic waveguide, and vibration isolation.\u0000The proposed selective actuation strategy offers a simple but effective way to\u0000control the tunable properties and thus enhance the programmability of\u0000magneto-mechanical metamaterials, which also expands the application space of\u0000magneto-mechanical metamaterials in elastic wave manipulation.","PeriodicalId":501083,"journal":{"name":"arXiv - PHYS - Applied Physics","volume":"45 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142177905","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}

引用次数: 0

Simultaneous Crystallization Effects in Multiple Levitated Plasma-Functionalized Graphene Nanoflake Nanofluid Droplets 多重悬浮等离子体功能化石墨烯纳米片纳米流体液滴中的同时结晶效应

arXiv - PHYS - Applied Physics Pub Date : 2024-09-11 DOI: arxiv-2409.07555

Adam McElligott, André Guerra, Alejandro D. Rey, Phillip Servio

{"title":"Simultaneous Crystallization Effects in Multiple Levitated Plasma-Functionalized Graphene Nanoflake Nanofluid Droplets","authors":"Adam McElligott, André Guerra, Alejandro D. Rey, Phillip Servio","doi":"arxiv-2409.07555","DOIUrl":"https://doi.org/arxiv-2409.07555","url":null,"abstract":"Acoustic levitation is a container-free method for examining novel\u0000crystallization effects, though liquid-to-solid phase change has seen little\u0000investigation for levitated nanofluids. Recent developments have allowed for\u0000examining the morphological and temperature evolution of multiple levitated\u0000nanofluid droplets freezing simultaneously. The fundamental effect of adding\u0000nanoparticles to a levitated crystallization system is crystal growth rate\u0000enhancement from improved mass transfer at the growing solid front. Nucleation\u0000times are unaffected as freezing is initiated by secondary ice nucleation\u0000particles (INPs). Instead, the enhancement produces higher instantaneous\u0000nucleation pressures and more cracking in the primary ice shell. In turn, more\u0000INPs are ejected, resulting in faster protrusion formation on the droplet\u0000surface (hastened further in systems containing adjacent droplets). The crystal\u0000matrix also includes more defects, resulting in liquid escaping and forming\u0000beads at the droplet base and optical clarity loss. During crystal\u0000decomposition, thermal gradients create convective currents dampened by the\u0000same transport phenomena that enhance crystal growth. Suspension loss after a\u0000crystallization-decomposition cycle reduced opacity and light absorbance such\u0000that the droplets were 62% closer in appearance to water. However, the\u0000non-isobaric, sample-encompassing cooling process resulted in smaller particle\u0000clusters than if the droplets were frozen on a solid surface.","PeriodicalId":501083,"journal":{"name":"arXiv - PHYS - Applied Physics","volume":"127 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142177904","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}

引用次数: 0

A Source-Independent Fault Detection Method for Transmission Lines 与源无关的输电线路故障检测方法

arXiv - PHYS - Applied Physics Pub Date : 2024-09-11 DOI: arxiv-2409.07439

Reza Jalilzadeh Hamidi, Julio Rodriguez

引用次数: 0

Sound Wave Manipulation Based on Valley Acoustic Interferometers 基于谷声干涉仪的声波操纵技术

arXiv - PHYS - Applied Physics Pub Date : 2024-09-11 DOI: arxiv-2409.07221

Wei Zhao, Jia-He Chen, Shu-Guang Cheng, Yong Mao, Xiaojun Zhang, Zhi Tao, Hua Jiang, Zhi Hong Hang

{"title":"Sound Wave Manipulation Based on Valley Acoustic Interferometers","authors":"Wei Zhao, Jia-He Chen, Shu-Guang Cheng, Yong Mao, Xiaojun Zhang, Zhi Tao, Hua Jiang, Zhi Hong Hang","doi":"arxiv-2409.07221","DOIUrl":"https://doi.org/arxiv-2409.07221","url":null,"abstract":"Topological acoustics provides new opportunities for materials with\u0000unprecedented functions. In this work, we report a design of topological valley\u0000acoustic interferometers by Y-shaped valley sonic crystals. By tight-bounding\u0000calculation and experimental demonstration, we successfully tune the acoustic\u0000energy partition rate by configuring the channel. An analytical theory proposed\u0000to explain the transmission property matches well with experimental\u0000observations. An additional {pi} Berry phase is verified to accumulate\u0000circling along the shape-independent topological valley acoustic\u0000interferometer, unique in the pseudospin half systems. Based on the spectral\u0000oscillation originating from the accumulated dynamic phase and {pi} Berry\u0000phase, a simplified method to measure acoustic valley interface dispersion is\u0000explored, which overcomes the shortcomings of the traditional fast Fourier\u0000transform method and improves the measuring efficiency by simply analyzing the\u0000peaks and dips of the measured transmission spectrum. Moreover, an effective\u0000approach to tuning its transmissions, as well as the spectral line shapes\u0000proposed and realized by the local geometry design of the interferometer,\u0000exhibits strong tunability under an unchanged physical mechanism. Our work\u0000opens an avenue to design future acoustic devices with the function of sound\u0000wave manipulation based on the physical mechanism of interference and Berry\u0000phase.","PeriodicalId":501083,"journal":{"name":"arXiv - PHYS - Applied Physics","volume":"31 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142177908","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}

引用次数: 0

The Potential of Geminate Pairs in Lead Halide Perovskite revealed via Time-resolved Photoluminescence 通过时间分辨光致发光揭示卤化铅包晶中双星对的潜力

arXiv - PHYS - Applied Physics Pub Date : 2024-09-10 DOI: arxiv-2409.06382

Hannes Hempel, Martin Stolterfoht, Orestis Karalis, Thomas Unold

{"title":"The Potential of Geminate Pairs in Lead Halide Perovskite revealed via Time-resolved Photoluminescence","authors":"Hannes Hempel, Martin Stolterfoht, Orestis Karalis, Thomas Unold","doi":"arxiv-2409.06382","DOIUrl":"https://doi.org/arxiv-2409.06382","url":null,"abstract":"Photoluminescence (PL) under continuous illumination is commonly employed to\u0000assess voltage losses in solar energy conversion materials. However, the early\u0000temporal evolution of these losses remains poorly understood. Therefore, we\u0000extend the methodology to time-resolved PL, introducing the concepts of\u0000geminate PL, doping PL, and sibling PL to quantify the transient chemical\u0000potential of photogenerated electron-hole pairs and key optoelectronic\u0000properties. Analyzing the initial PL amplitudes reveals hot charge carrier\u0000separation for around 100 nm and is likely limited by the grain size of the\u0000triple cation perovskite. The following PL decay is caused by the diffusive\u0000separation of non-excitonic geminate pairs and time-resolves a fundamental yet\u0000often overlooked energy loss by increasing entropy. For triple-cation halide\u0000perovskite, we measure a \"geminate correlation energy\" of up to 90 meV,\u0000persisting for ~ten nanoseconds. This energy is unutilized in standard solar\u0000cells and is considered lost in the Shockley-Queisser model. Therefore, this\u0000geminate energy could substantially enhance the device's efficiency,\u0000particularly under maximum power point and low-illumination conditions.","PeriodicalId":501083,"journal":{"name":"arXiv - PHYS - Applied Physics","volume":"15 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142177773","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}

引用次数: 0

On the negative capacitance in ferroelectric heterostructures 铁电异质结构中的负电容

arXiv - PHYS - Applied Physics Pub Date : 2024-09-10 DOI: arxiv-2409.06156

Yuchu Qin, Jiangyu Li

{"title":"On the negative capacitance in ferroelectric heterostructures","authors":"Yuchu Qin, Jiangyu Li","doi":"arxiv-2409.06156","DOIUrl":"https://doi.org/arxiv-2409.06156","url":null,"abstract":"Negative capacitance can be used to overcome the lower limit of subthreshold\u0000swing (SS) in field effect transistors (FETs), enabling ultralow-power\u0000microelectronics, though the concept of ferroelectric negative capacitance\u0000remains contentious. In this work, we analyze the negative capacitance in\u0000ferroelectric/dielectric heterostructure rigorously using Landau-Denvonshire\u0000theory, identifying three (one) critical dielectric thicknesses for first\u0000(second) order ferroelectric phase transition upon which the stability of\u0000negative capacitance changes. A critical electric window is also identified,\u0000beyond which the ferroelectric negative capacitance cannot be maintained.\u0000Between the first and second critical thicknesses, meta-stable negative\u0000capacitance exists near zero polarization, yet it will be lost and cannot be\u0000recovered when the electric window is broken. Between the second and third\u0000critical thicknesses, stable negative capacitance always exists near zero\u0000polarization within the electric window regardless of initial polar state,\u0000resulting in hysteretic double P-E loop. Beyond the third (first) critical\u0000thickness of first (second) order phase transition, P-E loop becomes hysteresis\u0000free, though the spontaneous polarization can still be induced at sufficient\u0000large electric field. Singularities in the effective dielectric constant is\u0000also observed at the critical thickness or electric field. The analysis\u0000demonstrates that the negative capacitance of ferroelectric can be stabilized\u0000by linear dielectric within a critical electric window, and the negative\u0000capacitance can be either hysteresis free or hysteretic for first order\u0000ferroelectrics, while it is always hysteresis free for the second order\u0000ferroelectrics.","PeriodicalId":501083,"journal":{"name":"arXiv - PHYS - Applied Physics","volume":"387 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142177771","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}

引用次数: 0

LaB6 aided spontaneous conversion of bulk graphite into carbon nanotubes at normal atmospheric conditions 在正常大气条件下，LaB6 有助于将块状石墨自发转化为碳纳米管

arXiv - PHYS - Applied Physics Pub Date : 2024-09-10 DOI: arxiv-2409.06410

Shalaka A. Kamble, Soumen Karmakar, Somnath R. Bhopale, Sanket D. Jangale, Neha P. Gadke, Srikumar Ghorui, S. V. Bhoraskar, M. A. More, V. L. Mathe

引用次数: 0

Role of Zr in Cu-rich single-phase and nanocomposite Cu-Zr: molecular dynamics and experimental study Zr 在富铜单相和纳米复合铜-Zr 中的作用：分子动力学和实验研究

arXiv - PHYS - Applied Physics Pub Date : 2024-09-10 DOI: arxiv-2409.06582

Jiri Houska, Mariia Zhadko, Radomir Cerstvy, Deepika Thakur, Petr Zeman

引用次数: 0