Korea-Australia Rheology Journal最新文献_第6页

Comparative study of two-relaxation time lattice Boltzmann and finite element methods for a planar 4:1 contraction flow: a Newtonian fluid at finite Reynolds numbers 有限雷诺数下牛顿流体平面4:1收缩流的双松弛时间晶格玻尔兹曼法与有限元法的比较研究

IF 1.3 4区工程技术

Korea-Australia Rheology Journal Pub Date : 2023-02-13 DOI: 10.1007/s13367-023-00052-3

Young Ki Lee

{"title":"Comparative study of two-relaxation time lattice Boltzmann and finite element methods for a planar 4:1 contraction flow: a Newtonian fluid at finite Reynolds numbers","authors":"Young Ki Lee","doi":"10.1007/s13367-023-00052-3","DOIUrl":"10.1007/s13367-023-00052-3","url":null,"abstract":"<div><p>We study the flow behavior of a Newtonian fluid in a planar 4:1 contraction channel using two numerical methodologies: the two-relaxation time lattice Boltzmann method (TRT-LBM) and the finite element method (FEM). To confirm the validity of the TRT-LBM, hydrodynamic quantities such that velocity, pressure, and vortex are carefully investigated at the wide ranges of Reynolds numbers (Re = 0.1–100). At first, we analyze the velocity along the channel. The results of TRT-LBM look reasonable and also coincide with the analytical solution and FEM results. Richer features are observed in the pressure profile along the flow direction. At low Reynolds numbers, the one-step change of the slope in the pressure profile is observed near the contraction region. The slope gradually grows up with the increase of Reynolds numbers, and eventually, this evolves the two-step change. Non-monotonic behavior is observed in the characteristics of the vortex. The size of the vortex non-linearly decreases as the Reynolds number increases. Also, the center of the vortex gradually moved toward the corner of the channel as an increase of Reynolds numbers with non-linearity. Not only the velocity and the pressure profiles but also the characteristics of the vortex quantitatively coincide in TRT-LBM and FEM results. Through this study, we confirm the robustness of the TRT-LBM as a simulation tool to investigate inertial flow in a planar contraction geometry.</p></div>","PeriodicalId":683,"journal":{"name":"Korea-Australia Rheology Journal","volume":"35 1","pages":"47 - 54"},"PeriodicalIF":1.3,"publicationDate":"2023-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s13367-023-00052-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4531445","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}

引用次数: 2

Dispersion of unfractionated microalgae in various polymers and its influence on rheological and mechanical properties 未分级微藻在各种聚合物中的分散及其对流变学和力学性能的影响

IF 1.3 4区工程技术

Korea-Australia Rheology Journal Pub Date : 2023-02-13 DOI: 10.1007/s13367-023-00050-5

Jin Hoon Yang, Jin-Ho Yun, Hee-Sik Kim, Joung Sook Hong, Kyung Hyun Ahn

{"title":"Dispersion of unfractionated microalgae in various polymers and its influence on rheological and mechanical properties","authors":"Jin Hoon Yang, Jin-Ho Yun, Hee-Sik Kim, Joung Sook Hong, Kyung Hyun Ahn","doi":"10.1007/s13367-023-00050-5","DOIUrl":"10.1007/s13367-023-00050-5","url":null,"abstract":"<p>This study investigates unfractionated microalgae (<i>Chlorella</i> sp. HS2 (HS2)) as a new resource of biomass to develop microalgae-based bioplastic materials. For the fabrication of microalgae-based bioplastics, HS2 is melt-compounded with various polymers with different solubility. In addition, lipid-extracted HS2 (HS2-LE) is tested to compare the dispersion of unfractionated microalgae. Dispersion of HS2 in the polymer is assessed with morphological observations and image analysis, further evaluated based on mechanical, thermal, FT-IR spectroscopic, and rheological measurements. HS2 disperses in polymer with broad size distribution and forms large millimeter-sized agglomerates throughout the composite regardless of type of polymers. Meanwhile, size distribution of HS2 aggregates is shifting to smaller region at mixing condition realizing strong stress transfer. For poly(ethylene–vinyl acetate) (EVA)/HS2 showing smaller size distribution, the addition of 10% HS2 increases elongation at break of EVA. Moreover, lipid-extracted HS2 (HS2-LE) increases further ductility and strength of EVA composite due to better dispersion of HS2-LE. This preliminary study to screen out of several polymers to develop microalgae-based bioplastics has brought out a potential of HS2 for bioplastic application.</p>","PeriodicalId":683,"journal":{"name":"Korea-Australia Rheology Journal","volume":"35 1","pages":"19 - 29"},"PeriodicalIF":1.3,"publicationDate":"2023-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4536892","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}

引用次数: 1

Thermoplastic resin transfer molding of carbon fiber reinforced polyamide 6 composite with the improved processability using zeolite particle 热塑性树脂传递模塑碳纤维增强聚酰胺6复合材料与改善加工性的沸石颗粒

IF 1.3 4区工程技术

Korea-Australia Rheology Journal Pub Date : 2023-02-08 DOI: 10.1007/s13367-023-00051-4

Jae Hyo Lee, Seung Mo Son, Jung Jae Yoo, Sang Woo Kim, Jin Woo Yi, Dong Gi Seong

{"title":"Thermoplastic resin transfer molding of carbon fiber reinforced polyamide 6 composite with the improved processability using zeolite particle","authors":"Jae Hyo Lee, Seung Mo Son, Jung Jae Yoo, Sang Woo Kim, Jin Woo Yi, Dong Gi Seong","doi":"10.1007/s13367-023-00051-4","DOIUrl":"10.1007/s13367-023-00051-4","url":null,"abstract":"<div><p>Thermoplastic resin transfer molding (T-RTM) of polyamide 6-based composite is one of the promising process to mass-produce an environmentally friendly textile composite with recyclable thermoplastic resin, in which ε-caprolactam monomer with low viscosity is injected and in situ polymerized into the fabric. The side reactions caused by water in the anionic polymerization process of the monomer is a crucial problem for fabricating the composite with a high quality. In this study, we introduced zeolite, a porous ceramic water-absorbing particle, into the ε-caprolactam to improve the moisture sensitivity during the anionic polymerization. The selective water-absorbing effect of zeolite particle was verified by measuring the monomer conversion, viscosity-average molecular weight, and viscosity change during polymerization, and mechanical properties of the resultant carbon fiber reinforced polyamide composite were investigated. It is expected that processability of the T-RTM is remarkably improved by reducing both the drying time during process and quality deviation of the composite by variation of humidity, which can make T-RTM process a viable technology for mass-production of thermoplastic composites.</p></div>","PeriodicalId":683,"journal":{"name":"Korea-Australia Rheology Journal","volume":"35 1","pages":"39 - 45"},"PeriodicalIF":1.3,"publicationDate":"2023-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4338278","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}

引用次数: 0

Rheological characterization of cellulose nanocrystal-laden self-healable polyvinyl alcohol hydrogels 纤维素纳米晶负载自愈聚乙烯醇水凝胶的流变学表征

IF 1.3 4区工程技术

Korea-Australia Rheology Journal Pub Date : 2023-01-31 DOI: 10.1007/s13367-023-00049-y

Hyeonjeong Kim, Hyo Jeong Kim, Youngeun Lee, Jin Kyung Kim, Youngho Eom

{"title":"Rheological characterization of cellulose nanocrystal-laden self-healable polyvinyl alcohol hydrogels","authors":"Hyeonjeong Kim, Hyo Jeong Kim, Youngeun Lee, Jin Kyung Kim, Youngho Eom","doi":"10.1007/s13367-023-00049-y","DOIUrl":"10.1007/s13367-023-00049-y","url":null,"abstract":"<div><p>Among various nanomaterials, cellulose nanocrystals (CNCs) are regarded as the most suitable reinforcing fillers for hydrogels owing to their high dispersibility in water and favorable hydrogen bonding with water-dispersible polymers. Herein, CNC-laden polyvinyl alcohol (PVA)/borax (P/CNC) hydrogels were prepared by solution mixing, and their mechanical and rheological properties were investigated in terms of CNC loading of 0–60 w/w%. PVA/borax hydrogels are known to exhibit self-healing ability based on the dynamic nature of the borate–diol complex, which is dependent on the rheological response because the rheological chain dynamics dominantly affect the self-healing process. In mechanical testing, the Young’s modulus of the P/CNC hydrogels sharply increased above 40 w/w% CNC, indicating that the stiffening effect of CNC was enhanced above the critical loading. From a rheological perspective, the increases in the viscosity and storage modulus were further accelerated above 40 w/w%. In particular, the chain flow relaxation time (<i>τ</i><sub>f</sub>), a quantitative parameter closely related to the self-healing performance, was observed for the P/CNC hydrogels with CNC amounts of 0−40 w/w% (1.6−97.3 s); whereas, there is no <i>τ</i><sub>f</sub> for the P/CNC hydrogels with 45−60 w/w% CNC within a reasonable time scale we observed at 25 °C. Consequently, the incorporation of less than 40 w/w% CNCs affords high mechanical stiffness while maintaining self-healing ability.</p></div>","PeriodicalId":683,"journal":{"name":"Korea-Australia Rheology Journal","volume":"35 1","pages":"31 - 38"},"PeriodicalIF":1.3,"publicationDate":"2023-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"5179251","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}

引用次数: 1

Correction: Rheological characteristics of the theta-shaped polymer under shear flow 修正:theta形聚合物在剪切流动下的流变特性

IF 1.3 4区工程技术

Korea-Australia Rheology Journal Pub Date : 2023-01-16 DOI: 10.1007/s13367-022-00048-5

Jun Mo Kim

引用次数: 0

Effect of solution pH on the microstructural and rheological properties in boehmite suspensions 溶液pH对薄水铝石悬浮液微观结构和流变性能的影响

IF 1.3 4区工程技术

Korea-Australia Rheology Journal Pub Date : 2022-12-12 DOI: 10.1007/s13367-022-00046-7

Gi Wook Lee, Seong Hwan Kim, Da Young Lee, Kwan-Young Lee, Byoungjin Chun, Hyun Wook Jung

{"title":"Effect of solution pH on the microstructural and rheological properties in boehmite suspensions","authors":"Gi Wook Lee, Seong Hwan Kim, Da Young Lee, Kwan-Young Lee, Byoungjin Chun, Hyun Wook Jung","doi":"10.1007/s13367-022-00046-7","DOIUrl":"10.1007/s13367-022-00046-7","url":null,"abstract":"<div><p>The relationship between microstructure changes and rheological properties in suspensions containing boehmite particles, which are well applied in various industrial wash-coating processes, was investigated by changing pH condition. The boehmite particles in suspensions were either well dispersed or aggregated depending on the pH, owing to the relative contributions of repulsive interaction between particles as well as hydrolysis and condensation reactions. Four groups of boehmite suspensions were classified as very low, intermediate, almost zero charge, and high pH regimes based on their colloidal behaviors, and their microstructural differences were investigated using transmission electron microscopy (TEM) and multi-speckle diffusing wave spectroscopy (MSDWS). For gel-like suspensions of three groups, various rheological properties such as shear viscosity, viscoelastic modulus, yield stress, and recovery behavior were extensively compared, and the results clearly demonstrated that a suspension with high yield stress was not fully recovered into the original state when disturbed at high shear rates.</p></div>","PeriodicalId":683,"journal":{"name":"Korea-Australia Rheology Journal","volume":"35 1","pages":"1 - 10"},"PeriodicalIF":1.3,"publicationDate":"2022-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4789488","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}

引用次数: 1

Plate gap effect on vicosity and rheological model of shear thickening fluid 板隙对剪切增稠流体粘度的影响及流变模型

IF 1.3 4区工程技术

Korea-Australia Rheology Journal Pub Date : 2022-12-10 DOI: 10.1007/s13367-022-00047-6

Shiwei Hou, Zhanwen Lai, Minghai Wei

{"title":"Plate gap effect on vicosity and rheological model of shear thickening fluid","authors":"Shiwei Hou, Zhanwen Lai, Minghai Wei","doi":"10.1007/s13367-022-00047-6","DOIUrl":"10.1007/s13367-022-00047-6","url":null,"abstract":"<div><p>The present work investigates the effect of plate gap on the rheological properties of shear thickening fluid (STF) and proposes a phenomenological model to predict the viscosity curve of STF for different values of plate gap and temperature. Multiwalled carbon nanotube (MWCNT) reinforced silica-based STF (MWCNT/SiO<sub>2</sub>-STF) containing 0.8 wt% MWCNT and 20 wt% SiO<sub>2</sub> nanoparticles was prepared using polyethylene glycol as a dispersion medium and tested for its steady and dynamic rheological behavior at different plate gaps. The peak viscosity of MWCNT/SiO<sub>2</sub>-STF follows the characteristic behavior of an initial increase followed by a subsequent decrease corresponding to the increase in plate gap. A maximum viscosity of 198.89 Pa s was recorded at a plate gap of 1.0 mm. Although significant shear thinning in the dynamic rheological response of MWCNT/SiO<sub>2</sub>-STF was noticed at a 1.0 mm gap, the storage and loss modulus were better than those at 0.5 mm gap. The proposed model based predicts the shear thinning and thickening behavior of STF at low and high shear rates for different values of plate gap with reasonable accuracy. The model also provides a very good fit for the viscosity of STF at different temperatures. Thus, the proposed model is suitable for numerical simulations as well as theoretical analysis in the vibration control field.</p></div>","PeriodicalId":683,"journal":{"name":"Korea-Australia Rheology Journal","volume":"35 1","pages":"11 - 18"},"PeriodicalIF":1.3,"publicationDate":"2022-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4415485","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}

引用次数: 1

Publisher Correction: Effect of initial solvent concentration on the structure and property of polymer nanocomposites 初始溶剂浓度对聚合物纳米复合材料结构和性能的影响

IF 1.3 4区工程技术

Korea-Australia Rheology Journal Pub Date : 2022-10-31 DOI: 10.1007/s13367-022-00045-8

Ga Young Kim, Tae Yeon Kong, So Youn Kim

引用次数: 0

Rheological characteristics of the theta-shaped polymer under shear flow 剪切流动下theta形聚合物的流变特性

IF 1.3 4区工程技术

Korea-Australia Rheology Journal Pub Date : 2022-10-06 DOI: 10.1007/s13367-022-00044-9

Jun Mo Kim

{"title":"Rheological characteristics of the theta-shaped polymer under shear flow","authors":"Jun Mo Kim","doi":"10.1007/s13367-022-00044-9","DOIUrl":"10.1007/s13367-022-00044-9","url":null,"abstract":"<div><p>We present the structural, dynamical, and rheological behaviors of theta chains according to the solution type and the molecular architecture, using extensive bead-rod Brownian simulations, and compare them with the corresponding pure ring chain. Through detailed analysis of the properties of theta chains in each solution system, we found that theta chains have their own chain structure for each solution system and, accordingly, a characteristic dynamical behavior in each solution. For example, due to the absence of intra and intermolecular interactions in the free-draining solution system, the theta chain can have a fully stretched structure and can rotate like a conventional linear chain. On the other hand, due to the presence of intra and intramolecular interactions in the dilute solution system, the theta chain can have a spread (or extended) chain configuration that is aligned parallel to the flow-vorticity plane under shear flow, resulting in a two dimensional (2D) planar sheet-like chain structure. Thus, the theta chain alternates between the 2D planar sheet structure and the folded sheet structure during the chain rotation and tumbling cycle. We also found that the structural, dynamical, and rheological properties of the theta chains are highly dependent on the existence of a bridged linear part of the theta chain irrespective of the solution type. Since the bridged part of the theta chain physically prevents chain extension induced by a strong shear flow, the theta chains tend to have a less deformed chain structure than the corresponding pure ring chain. Depending on the length of the branched part of the theta chain, the rotation and tumbling behavior of the theta chain are greatly modified.</p></div>","PeriodicalId":683,"journal":{"name":"Korea-Australia Rheology Journal","volume":"34 4","pages":"381 - 393"},"PeriodicalIF":1.3,"publicationDate":"2022-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4279261","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}

引用次数: 1

Lateral particle migration in shear-thinning colloidal dispersion 剪切变薄胶体分散中的横向颗粒迁移

IF 1.3 4区工程技术

Korea-Australia Rheology Journal Pub Date : 2022-10-06 DOI: 10.1007/s13367-022-00043-w

Young Hwan Kim, Tae Soup Shim, Ju Min Kim

{"title":"Lateral particle migration in shear-thinning colloidal dispersion","authors":"Young Hwan Kim, Tae Soup Shim, Ju Min Kim","doi":"10.1007/s13367-022-00043-w","DOIUrl":"10.1007/s13367-022-00043-w","url":null,"abstract":"<div><p>Colloidal dispersions have been frequently encountered in a wide range of industrial applications, such as foods, paints, and Li-ion electrode slurries. Therefore, it is essential to understand the rheological and flow characteristics of colloidal dispersions to improve the quality and optimize the processing conditions of colloidal products. The shear viscosity of a colloidal dispersion deviates from Newtonian behavior, exhibiting shear thinning and/or shear thickening as the volume fraction of the colloidal particles increases. However, there are not many reports on the non-Newtonian flow phenomena caused by the normal stress differences of colloidal dispersion due to their small magnitude. Recently, these normal stress differences in colloidal dispersions with a constant shear viscosity lead to a single-line focused streams of micron-sized particles along the centerline of microchannels. In this study, the lateral migration of single micron-sized particles suspended in poly (<i>N</i>-isopropylacrylamide) microgel dispersions with a shear-thinning viscosity was investigated. The micron-sized particles migrated toward the centerline or between the centerline and wall of a microchannel depending on the volume fraction of the colloidal particles and the flow conditions. The current findings are expected to contribute to our understanding of the non-Newtonian fluid dynamics in colloidal dispersions and flow-induced particle segregation phenomenon.</p></div>","PeriodicalId":683,"journal":{"name":"Korea-Australia Rheology Journal","volume":"34 4","pages":"327 - 334"},"PeriodicalIF":1.3,"publicationDate":"2022-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4279260","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}

引用次数: 1