Korea-Australia Rheology Journal最新文献

{"title":"Rheological properties of silica-based shear thickening fluids reinforced with silicon nitride and carbon nanotubes","authors":"Yalin Zheng,&nbsp;Minghai Wei,&nbsp;Guangpeng Zhang,&nbsp;Aoping You","doi":"10.1007/s13367-026-00150-y","DOIUrl":"10.1007/s13367-026-00150-y","url":null,"abstract":"<div>\u0000 \u0000 <p>This study fabricates SiO₂/Si₃N₄/MWCNT shear-thickening fluids (STFs) based on nanoparticles silicon dioxide (SiO₂), silicon nitride (Si₃N₄), and multi-walled carbon nanotubes (MWCNT). The research investigates the effects of MWCNT mass fraction, ambient temperature, and gap distance on the shear thickening (ST) performance through rheological experiments. Scanning electron microscopy and X-ray diffraction confirm the presence of MWCNT and Si₃N₄ nanoparticles within the multiphase STF (MSTF), as well as their interactions with SiO₂ nanoparticles. Steady shear rheology tests reveal significant rheological behavior and a pronounced ST effect in SiO₂/Si₃N₄/MWCNT-STF with varying mass ratios. The optimal mass ratio of SiO₂, Si₃N₄, and MWCNT is found to be 20:2.5:0.8, at which point the ST performance of the MSTF is maximized. The peak viscosity increases from 65.83 Pa s (20:2.5:0.2) to 516.2 Pa s (20:2.5:0.8), while the critical shear rate decreases from 63.1 s⁻¹ to 6.31 s⁻¹. Dynamic rheology tests demonstrate that the 20%SiO₂/2.5%Si₃N₄/0.8%MWCNT-STF exhibit not only significant energy storage and dissipation capabilities but also enhanced rate sensitivity in energy storage and dissipation compared to silicon-based STF (SiO₂-STF) under lower rate excitations. Temperature sensitivity studies indicate that MSTF maintain excellent ST characteristics even in high-temperature environments. In comparison to SiO₂-STF, the variation in peak viscosity and critical shear rate of MSTF with increasing temperature is significantly reduced, demonstrating superior temperature stability and offering potential for engineering applications in higher temperature environments.</p>\u0000 <span>AbstractSection</span>\u0000 Graphical abstract\u0000 <div><figure><div><div><picture><source><img></source></picture></div></div></figure></div>\u0000 \u0000 </div>","PeriodicalId":683,"journal":{"name":"Korea-Australia Rheology Journal","volume":"38 1","pages":"107 - 121"},"PeriodicalIF":2.6,"publicationDate":"2026-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147336686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the relaxation time spectrum recovery from the stress relaxation test data using Post-Widder inversion formula and double-logarithmic-power-series model","authors":"Anna Stankiewicz","doi":"10.1007/s13367-025-00149-x","DOIUrl":"10.1007/s13367-025-00149-x","url":null,"abstract":"<div><p>The problem of recovering the relaxation time spectrum from discrete-time relaxation modulus measurement data is considered using the Post-Widder inversion formula and based on double-logarithmic-series-power model of the relaxation modulus. Using the specific properties of this relaxation modulus model, the product of the arbitrarily high power of time and the same order derivative of the relaxation modulus, which is the basis for the Post-Widder inversion rule, was expressed by analytical formula given by the series of recurrence-type, defined by the modulus model and triple-indexed integer coefficients introduced by simple recurrence equations. As a result, a new sequence of the Post-Widder approximations of the relaxation time spectrum was derived, given by recursive-type analytical formula. Two-stage identification scheme is presented for the relaxation spectrum model determination. In the first stage, the optimal double-logarithmic-series-power model is determined using Tikhonov-regularized linear least-squares method, applied to the log-transformed model and the relaxation modulus measurement data. Then, in the second identification stage, the calculation of the relaxation spectrum model is based on the recursive analytical formula of the Post-Widder approximation of arbitrarily high order. Finally, an example of the identification of the Baumgaertel-Schausberger-Winter spectrum is presented, which is characterized by a very wide range of relaxation times. It has been shown that the proposed method provides a very good approximation of the actual relaxation spectrum even for strong measurement noises.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture><span>The alternative text for this image may have been generated using AI.</span></div></div></figure></div></div>","PeriodicalId":683,"journal":{"name":"Korea-Australia Rheology Journal","volume":"38 2","pages":"125 - 150"},"PeriodicalIF":2.6,"publicationDate":"2026-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147862996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Patient-specific hemodynamic assessment of cerebral aneurysms treated with braided stents using immersed boundary method: computational fluid dynamics study","authors":"Ihab Omar,&nbsp;Nashmi H. Alrasheedi,&nbsp;As’ad Alizadeh,&nbsp;Abdellatif M. Sadeq,&nbsp;Ashraf Abed Hussein,&nbsp;Husam Rajab,&nbsp;Narinderjit Singh Sawaran Singh,&nbsp;Walid Aich","doi":"10.1007/s13367-025-00147-z","DOIUrl":"10.1007/s13367-025-00147-z","url":null,"abstract":"<div><h3>Background and objective</h3><p>Intracranial aneurysms in the internal carotid artery (ICA) pose significant clinical risk, particularly in the presence of abnormal hemodynamics exacerbated by arterial dilation. Flow-diverting stents offer a promising endovascular solution, yet their efficacy depends strongly on the interaction between device geometry and local blood flow dynamics.</p><h3>Methods</h3><p>This study employs a patient-specific computational fluid dynamics (CFD) framework to assess the hemodynamic effects of two braided stent models-standard and dense-implanted in an aneurysmal ICA. A high-fidelity immersed boundary method (IBM) is implemented to embed the stent geometry within the fluid domain without requiring mesh conformity. Simulations were performed under physiologically realistic pulsatile conditions using a non-Newtonian blood rheology model. Comparative analyses were conducted against a baseline (no-stent) model to evaluate spatial and temporal patterns of wall shear stress (WSS), time-averaged WSS (TAWSS), oscillatory shear index (OSI), and intra-aneurysmal velocity fields.</p><h3>Results</h3><p>Results reveal that the standard and dense stents reduced peak area-averaged WSS on the aneurysm wall by approximately 64% and 78%, respectively, compared to the no-stent model. The dense stent further achieved near-complete suppression of OSI, indicating a more stable hemodynamic environment.</p><h3>Conclusion</h3><p>These findings suggest that increasing stent mesh density enhances flow diversion and may improve long-term therapeutic outcomes in ICA aneurysm management.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":683,"journal":{"name":"Korea-Australia Rheology Journal","volume":"38 1","pages":"79 - 91"},"PeriodicalIF":2.6,"publicationDate":"2026-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147342424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Solvent-assisted mixing of Ag/MWCNT/PDMS composites for stretchable conductors","authors":"Ji-Won Kang,&nbsp;Eun Hui Jeong,&nbsp;Jun Dong Park,&nbsp;Byoung Soo Kim","doi":"10.1007/s13367-025-00144-2","DOIUrl":"10.1007/s13367-025-00144-2","url":null,"abstract":"<div><p>Incorporating metallic particles in a soft polymer matrix provides a practical and cost-effective route to electrically conductive stretchable materials. Reliable performance depends critically on the microstructure established before matrix curing, which is governed by the rheology of the uncured composite paste. This study presents a solvent-assisted formulation strategy that exploits solvent-polymer compatibility to adjust viscosity during mixing and evaporation, subsequently regulating filler migration and network consolidation. Using silver (Ag) particles and multiwalled carbon nanotubes (MWCNTs) in a polydimethylsiloxane (PDMS) matrix, we show that solvent-assisted processing enhances electrical performance under strain by promoting the formation of a percolated CNT-bridging network. The composite fabricated without solvent exhibits a monotonic modulus decrease, indicating localized and poorly dispersed MWCNT aggregates. In contrast, solvent-assisted mixing produces pronounced strain stiffening, evidencing formation of a flexible, percolated MWCNT network. Among solvent-processed samples, the isopropyl alcohol (IPA)–assisted composite shows the most distinct stiffening response, suggesting a more homogeneous and extended network than that formed with chloroform. At identical Ag loading, IPA processing maintains stable electrical resistance up to ~ 80% tensile strain and reduces hysteresis during cyclic loading, whereas chloroform processing shows resistance escalation near 70% strain. These findings demonstrate that solvent-assisted processing, particularly with IPA, markedly improves filler dispersion and structural integrity in Ag/MWCNT/PDMS stretchable conductors.</p><h3>Graphical Abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":683,"journal":{"name":"Korea-Australia Rheology Journal","volume":"38 1","pages":"37 - 44"},"PeriodicalIF":2.6,"publicationDate":"2026-01-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147342116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study of the printability and rheological behavior of inks formulated with collagen- polycaprolactone-chitosan","authors":"Angela Miscli Rangel-Garcia,&nbsp;Luis Medina-Torres,&nbsp;Octavio Manero,&nbsp;Marco Antonio Álvarez-Pérez,&nbsp;María Cristina Piña-Barba","doi":"10.1007/s13367-025-00148-y","DOIUrl":"10.1007/s13367-025-00148-y","url":null,"abstract":"<div>\u0000 \u0000 <p>The development of inks for use in 3D printing remains a significant challenge in the field of tissue engineering. In this study, the dimensionless printability factor is calculated by comparing printed images with the desired design, resulting in a value of 0.87 ± 0.11 for ink with the lowest polycaprolactone (PCL) content. A filament collapse test was conducted to ascertain the grid pore size, with results attained within the range of 0.60 to 1 mm. The rheological behavior of inks formulated with collagen (Col), polycaprolactone (PCL) and chitosan (Chi) exhibit shear-thinning viscosity, and decreasing rheological properties with increasing temperature. The storage (G′) and loss (G′′) moduli increase with increasing angular frequency. Results reveal that increasing polymer concentration improves printability and rheological properties of the Col: PCL: Chi inks, allowing the printing of scaffolds with regulated properties leading to important applications in tissue engineering.</p>\u0000 </div>","PeriodicalId":683,"journal":{"name":"Korea-Australia Rheology Journal","volume":"38 1","pages":"93 - 106"},"PeriodicalIF":2.6,"publicationDate":"2026-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s13367-025-00148-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147338871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Instability-driven microstructural evolution in drying bidisperse colloidal films","authors":"Jinseong Yun,&nbsp;Byoungjin Chun,&nbsp;Hyun Wook Jung","doi":"10.1007/s13367-025-00145-1","DOIUrl":"10.1007/s13367-025-00145-1","url":null,"abstract":"<div>\u0000 \u0000 <p>We investigate the coupled effects of evaporation and sedimentation on the microstructural evolution of bidisperse colloidal films using lattice Boltzmann simulations. The drying process is examined under both continuous drying and a two-step drying protocol, in which a temporary interruption period is introduced during the rapid drying stage. Under continuous drying, the competition between evaporative accumulation and gravitational settling leads to distinct outcomes: a pronounced small-on-top stratification when large particles undergo stronger sedimentation, and a much weaker degree of such stratification when the sedimentation rates of the two particle types are comparable. When drying is temporarily paused, the dense particle layer formed near the air–liquid interface becomes gravitationally unstable, and exhibits Rayleigh–Taylor instability. During this quiescent period, size-dependent vertical stratification relaxes, while new lateral patterns featuring finger-like structures emerge. These lateral patterns subsequently influence the final film configuration, ultimately producing alternating regions enriched in small and large particles. These findings demonstrate that drying-induced instability through a two-step drying protocol provides a promising route for designing unique microstructures in colloidal films.</p>\u0000 <span>AbstractSection</span>\u0000 Graphical Abstract\u0000 <div><figure><div><div><picture><source><img></source></picture></div></div></figure></div>\u0000 \u0000 </div>","PeriodicalId":683,"journal":{"name":"Korea-Australia Rheology Journal","volume":"38 1","pages":"45 - 52"},"PeriodicalIF":2.6,"publicationDate":"2025-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147339793","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Physics-informed neural networks for complex fluids: opportunities and limitations","authors":"Jungwon Sa,&nbsp;Byeongju Jeon,&nbsp;Yonghyeon Seo,&nbsp;Jaeuk Lim,&nbsp;Siyoung Q. Choi","doi":"10.1007/s13367-025-00140-6","DOIUrl":"10.1007/s13367-025-00140-6","url":null,"abstract":"<div><p>Physics-informed neural networks (PINNs) offer a transformative alternative to conventional computational fluid dynamics (CFD) by embedding governing physical laws directly into neural network loss functions. While traditional CFD methods face limitations including high computational costs, mesh sensitivity, and extensive data requirements, PINNs overcome these barriers by ensuring solutions inherently satisfy conservation principles during training. This review examines PINN foundations and their dual capability in solving forward problems—predicting complex fluid behaviors—and inverse problems involving parameter identification from limited data. We categorize existing research across three dimensions: canonical flows (Couette, Poiseuille), constitutive models (non-Newtonian, viscoelastic), and mathematical formulations (Burgers, Cahn-Hilliard equations). Building on this framework, we discuss advanced PINN variants addressing limitations in accuracy, efficiency, and generalization. We conclude by outlining future directions in multiscale modeling, irregular geometries, and data-driven discovery of constitutive laws, highlighting PINNs’ potential to revolutionize computational strategies for complex fluids.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":683,"journal":{"name":"Korea-Australia Rheology Journal","volume":"37 3-4","pages":"469 - 492"},"PeriodicalIF":2.6,"publicationDate":"2025-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s13367-025-00140-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145898461","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of polymer concentration on the wake structure for the viscoelastic flow behind a square cylinder","authors":"Om Prakash Pandit,&nbsp;Dipankar Chatterjee,&nbsp;Sourabh Khambra","doi":"10.1007/s13367-025-00146-0","DOIUrl":"10.1007/s13367-025-00146-0","url":null,"abstract":"<div><p>The work investigates numerically the influence of elastic force and polymer concentration on the behavior of two-dimensional viscoelastic flow past a square cylinder. The Oldroyd-B constitutive model is implemented for the characterization of the viscoelastic flow behavior. The coupled conservation and the constitutive equations are solved using a finite volume method in a non-uniform structured collocated grid system. The roles of the Weissenberg number (<i>Wi</i>) and the polymer viscosity ratio (1-<i>β</i>) are studied for the range <span>(0 le Wi le 5)</span>, 1-<i>β</i> = 0.01, 0.04, and 0.1 and Reynolds number <span>(10 le {text{Re}} le 4)</span> 0. The elastic force causes suppression of the wake behind the object while the polymer concentration leads to an increase in the stretching strength of the wake. A fully developed flow in a confined domain of blockage ratio 0.1 is considered for the study. It is observed that higher the value of <i>Re</i> and the polymer viscosity (1-<i>β</i>), a lower <i>Wi</i> is required for the wake suppression. The wake behind the square cylinder increases in both lateral and longitudinal directions with an increase of <i>Wi</i> and polymer viscosity ratio (1-<i>β</i>). It is further observed that the influence of polymer viscosity ratio on the flow structure around the cylinder has a significant impact in increasing the wake size and drag force at low <i>Wi</i> and <i>Re</i>.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":683,"journal":{"name":"Korea-Australia Rheology Journal","volume":"38 1","pages":"53 - 77"},"PeriodicalIF":2.6,"publicationDate":"2025-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147338817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"From 3D particle structuring to the 3D printing of silicones: A review","authors":"Chanyoung Kang,&nbsp;Ryun Oh,&nbsp;Daehoon Han,&nbsp;Yeongun Ko,&nbsp;Sangchul Roh","doi":"10.1007/s13367-025-00139-z","DOIUrl":"10.1007/s13367-025-00139-z","url":null,"abstract":"<div><p>Silicones, a class of elastomers, are widely used in various applications, including soft robotics, microfluidic devices, biomedical materials, flexible electronics, and wearable sensors. 3D printing is one of the rapidly growing additive manufacturing methods for 3D structuring of materials, and it can expand the use of silicones for diverse applications. For an extrusion-type 3D printing process, such as direct ink writing, the inks require specific rheological properties. However, silicones typically exist as a viscous fluid, making it challenging to 3D print them without additional treatment, such as the incorporation of rheology modifiers. Here, we review common fillers used to modify the rheological properties of silicone for extrusion-based 3D printing. We discuss filler structuring and the resulting emergent rheological properties of silicone. We also review past studies on the applications of 3D-printed silicones with rheology modifiers.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":683,"journal":{"name":"Korea-Australia Rheology Journal","volume":"37 3-4","pages":"455 - 468"},"PeriodicalIF":2.6,"publicationDate":"2025-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145898460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rheology of physiological fluids and their artificial substitutes","authors":"Jinhyeong Lee,&nbsp;Jiho Choi","doi":"10.1007/s13367-025-00141-5","DOIUrl":"10.1007/s13367-025-00141-5","url":null,"abstract":"<div><p>Biological fluids exhibit complex rheological behaviors that are essential for physiological function and significantly altered in disease. Direct studies of native fluids, however, are constrained by invasive sampling, variability, and limited reproducibility, underscoring the importance of developing mimicking fluids. Unlike early substitutes based on Newtonian solutions, next-generation mimicking systems aim to reproduce non-Newtonian features such as thixotropy, and pH-dependent transitions. Recent advances highlight multicomponent formulations and simulation frameworks that more faithfully capture the defining rheological signatures of biofluids, yet most approaches remain preliminary and rely on simplified or animal-derived components. This review synthesizes progress in mimicking systems for major biofluids, identifies current challenges including limited pathological data and lack of standardized protocols, and emphasizes the need for integrated experimental and computational strategies. Looking ahead, future efforts should combine microstructural characterization, standardized rheological databases, and AI-enhanced modeling with sustainable materials. Such developments will establish physiologically accurate and reproducible mimicking fluids, enabling broad applications in diagnostics, medical device testing, and precision medicine.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":683,"journal":{"name":"Korea-Australia Rheology Journal","volume":"37 3-4","pages":"431 - 454"},"PeriodicalIF":2.6,"publicationDate":"2025-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145898350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}