Analysis of thermal management and anti-mechanical abuse of multi-functional battery modules based on magneto-sensitive shear thickening fluid

Electric vehicles(EVs)have garnered significant attention as a vital driver of economic growth and environmental sustainability.Nevertheless,ensuring the safety of high-energy batteries is now a top priority that cannot be overlooked during large-scale applications.This paper proposes an innovative active protection and cooling integrated battery module using smart materials,magneto-sensitive shear thickening fluid(MSTF),which is specifically designed to address safety threats posed by lithium-ion batteries(LIBs)exposed to harsh mechanical and environmental conditions.The theoretical framework introduces a novel approach for harnessing the smoothed-particle hydrodynamics(SPH)methodology that incorporates the intricate interplay of non-Newtonian fluid behavior,capturing the fluid-structure coupling inherent to the MSTF.This approach is further advanced by adopting an enhanced Herschel-Bulkley(H-B)model to encapsulate the intricate rheology of the MSTF under the influence of the magnetorheological effect(MRE)and shear thickening(ST)behavior.Numerical simulation results show that in the case of cooling,the MSTF is an effective cooling medium for rapidly reducing the temperature.In terms of mechanical abuse,the MSTF solidifies through actively applying the magnetic field during mechanical compression and impact within the battery module,resulting in 66%and 61.7%reductions in the maximum stress within the battery jellyroll,and 31.1%and 23%reductions in the reaction force,respectively.This mechanism effectively lowers the risk of short-circuit failure.The groundbreaking concepts unveiled in this paper for active protection battery modules are anticipated to be a valuable technological breakthrough in the areas of EV safety and lightweight/integrated design.

An experimental study on shock wave mitigation capability of polyurea and shear thickening fluid based suspension pads

The present experimental study investigates shock wave mitigation capability of potentially new personal protective equipment(PPE) suspension pads made from polyurea and shear thickening fluid(STF).The shock tube test results show that when placed behind Twaron fabric systems with thickness ranging from 2 mm to 18 mm, the replacement of conventional flexible foam pad with STF and STF-infused foam pads with the same thickness of 20 mm greatly reduces the normalized peak pressure(by about 72% for each pad). However, this benefit is partially offset by a large increase in the normalized impulse(by about78% for the STF pad and 131% for the STF-infused foam pad) which may cause the shock wave mitigation performance of these two pads to become less effective. Interestingly, the use of 4 mm thick polyurea pad can greatly reduce the normalized peak pressure and impulse as well(by about 74% and 49%, respectively). These results reveal that among the potentially new suspension pads tested, the polyurea pad displays the best shock wave mitigation performance. Therefore, polyurea has potential for use as a suspension pad in personal protective equipment requiring shock wave mitigation capability such as fabric ballistic vests, bomb suits and combat helmets.

An experimental study on ballistic impact response of jute reinforced polyethylene glycol and nano silica based shear thickening fluid composite

The present study aims at assessing the ballistic impact behaviour of jute reinforced polyethylene glycol(PEG)and nano silica based shear thickening fluid(STF).Preparation of STF is achieved by dispersing the nano silica particles at different weight percentage loadings of 10%,20%,30%and 40%in PEG and the effect of various weight percentages loading of nano silica particles on ballistic performance of the proposed composites is studied experimentally.Rheological studies of the prepared STF’s showed that at all nanosilica loading shear thickening occurred and also the shear thickening was highest at higher loading of nano silica at lower rate of shear.The study reveals that the ballistic performance of the jute fabric is enhanced with impregnation of STF.The ballistic results indicate that energy absorption of the proposed composites is enhanced with increased loading of nano silica particles and at the same time,the effect of STF was reduced.Specific energy absorption(SEA)of the neat fabric and the proposed composites was made use of for the purpose of comparing the energy absorption capabilities.It is found that the SEA of proposed composites with 10%nano silica loading is lesser than the neat fabric both in case of 3 layers and 6 layers.It was also found that proposed composite with 40%nano silica loading exhibits highest SEA compared to neat fabric and its counterparts with its SEA being 3.21 and 3.76 times highest compared to three and six layers of neat fabrics respectively.

剪切增稠流体在Kevlar复合材料中的应用研究进展

高强度、高韧性、低密度的凯夫拉(Kevlar)材料在防护领域广泛应用,但直接使用Kevlar织物制备防护材料会使其过于笨重。因此,人们研究了轻质灵活的Kevlar复合材料,使用剪切增稠流体来增强其性能。本综述总结了使用不同分散相和分散介质的剪切增稠流体浸渍Kevlar复合材料的研究进展,旨在为防护材料的后续研究提供思路。

剪切增稠液增强高发泡率废纸缓冲材料的制备及性能

随着经济的快速增长和人们环保意识的不断增强,植物纤维类环保型发泡缓冲材料逐渐成为研究热点。为改善植物纤维发泡材料发泡率低、缓冲吸能效果差等问题,本研究设计半密闭型发泡模具,成功制备了具有高发泡率和优异吸能性的废纸缓冲材料并对制备工艺进行了优化。结果表明:使用质量分数为0.5%的氢氧化钠溶液预处理废纸浆,不仅可以有效去除废纸中的杂质,而且能在不降低纤维长度的情况下对废纸纤维进行适当改性,有利于提高废纸缓冲材料的发泡率和整体性能。以正交优化试验研究原料配比对废纸缓冲材料性能的影响,并据此确定了最优配方。通过设计全新半密闭型发泡模具,成功制备高发泡率的废纸缓冲材料,其膨胀率相较传统制备方式提高了3~4倍。本研究首次引入剪切增稠液(STF)增强废纸纤维,考察了STF含量对废纸缓冲材料力学性能、发泡倍率和回弹性能的影响,分析了STF对废纸缓冲材料的增强机理。结果表明:STF能够提高单根废纸纤维的强度并增强纤维之间的连结,从而提升缓冲材料吸能性,且随着STF含量的增加,材料的吸能性逐渐增强,发泡率逐渐降低,当STF含量为10%(质量分数,下同)时,STF增强废纸缓冲材料的综合性能达到最优。

SiO_(2)/聚乙二醇200/碳纳米管剪切增稠液浸渍芳纶织物及其复合材料防刺性能

为优化高性能织物的防刺性能,采用SiO 2和不同长径比的多壁碳纳米管(MWCNTs)制备多相剪切增稠液(MSTFs),研究MWCNTs的长径比与添加量对剪切增稠液流变性能的影响及MSTFs芳纶复合织物的防刺性能。之后将MSTFs复合织物与碳化硅/聚氨酯(SiC/TPU)涂层织物叠层制备双层防刺复合材料,探究叠层顺序对层合复合材料抗穿刺性能的影响。结果得出:长径比较大的碳纳米管对提高剪切增稠液(STF)的增稠效果更优;随着碳纳米管含量的增加,剪切增稠效果逐渐增强。实验结果表明:MSTFs(0.4%MWCNTs-A)浸渍芳纶织物的最大穿刺载荷较纯STF浸渍芳纶织物提高154.33%;不同叠层结构中以剪切增稠液浸渍织物为面层、SiC/TPU涂层织物为背层的双层复合织物表现出更优的防刺性能。

Mechanical response of encapsulated shear thickening fluid

In this investigation,the hard-to-handle shear thickening fluid(STF)is successfully encapsulated for easy handling and re-processing in the application of promising impact resistant material.Double-walled macroscopic STF capsules are synthesized using a convenient process by instilling the diluted STF droplets into reaction solution.The obtained STF capsules show significant shear thickening response to dynamic impact in comparison to quasistatic compression in terms of 154 times higher absorbed nominal strain energy.This innovative method opens a new window to design and manufacture versatile impact resistant materials and structures.

On Free Boundary Problem for the Non-Newtonian Shear Thickening Fluids

The aim of this paper is to explore the free boundary problem for the NonNewtonian shear thickening fluids.These fluids not only have vacuum,but also have strong nonlinear properties.In this paper,a class of approximate solutions is first constructed,and some uniform estimates are obtained for these approximate solutions.Finally,the existence of free boundary problem solutions is proved by these uniform estimates.

Applications of shear thickening fluids: a review

Shear thickening fluids (STFs) are a type of non-Newtonian fluids. In the equilibrium state, the STFs are in liquid-state. However, they become solid-state under a sudden strike or impact. And when the strike or impact is removed, the STFs can turn back to their equilibrium properties. This paper provides a detailed review on relevant literature related to the applications with shear thickening fluids. It introduced the factors affecting shear-thickening behaviour including volume fraction, particle size, particle shape, carrier fluid viscosity, temperature and some other factors.

On the Study of Magneto-Hydrodynamic Non-Newtonian Fluid Flow throughout Curvilinear Channel with Corrugated Walls

This article aims to numerically investigate the flow pattern for Newtonian and power law non-Newtonian fluid in a semi-half circular channel with corrugated walls under the influence of a magnetic field. The results indicate that, presence of a magnetic field affects the flow field in several aspects, especially in the vortex creation and dissipation. In addition, the analysis is carried out for different Reynolds numbers to ascertain the influence of magnetic field on each flow regime. Eventually, the analysis is carried out for a range of power indices including pseudo plastic (shear-thinning) to dilatants (shear-thickening) fluids. The results show that by increasing the power-index, the vortices begin to form and grow gradually so that in the shear-thickening fluid an extra vortex is formed and created nearby the corrugated part of the channel.

剪切增稠液及其复合织物动态力学行为与数值研究进展

剪切增稠液(shear thickening fluids,STFs)是一种新型智能液体装甲材料,与织物复合时可有效提升织物抗冲击能力,在结构冲击领域有广阔的应用潜力。该研究对STF及其增强织物的动态力学行为与数值仿真方法最新进展进行了综述和评价,介绍了STF剪切增稠机理及流变特性的主要影响因素,讨论了STF和STF复合织物的动态力学行为及本构模型,分析了STF复合织物的抗冲击性能的影响因素及STF对织物的增强机理,讨论了STF复合织物在数值仿真方法研究方面的最新进展。最后对STF及其增强织物的力学行为研究进行了总结,并对STF的发展趋势进行了展望。

剪切增稠液及其吸能减振作用研究进展

目的 研究剪切增稠液(Shear Thickening Fluid, STF)及其吸能减振方面的应用,为实现更好的结构振动控制效果提供参考。方法 通过文献调查法和文献研究法,系统综述了剪切增稠液及其在吸能减振方面的应用,并重点介绍了在STF制备开发中实现复合功能所面临的挑战,如STF增稠机理需要完善、STF功能开发范围较为单一、STF振动控制应用有待拓展等。结果 剪切增稠液作为一种新兴的高阻尼智能材料,在材料制备、性能调控、成因机理和应用开发等方面取得了丰硕的研究成果;将剪切增稠液替代传统黏滞阻尼器的阻尼介质,可以显著提高黏滞阻尼器的耗能减振能力,也可用于隔震系统中以缓解隔震层的变形,从而有效保障结构抗震的安全性。结论 为进一步拓展STF的实用性,建议研究热点应更多关注功能化STF组分的引入以及与其他智能材料的复合应用,开发出具有复合功能的STF,便于更好地应用于实际项目或在结构构件中发挥其作用。

压裂用耐温乳液稠化剂的制备及性能

为发展耐温疏水聚合物压裂液体系,本文在丙烯酰胺、丙烯酸、2-丙烯酰胺-2-甲基丙磺酸(AMPS)中引入了疏水单体甲基丙烯酸十八烷基酯来提高稠化剂的耐温性,合成了聚合物稠化剂PAS。实验结果表明,制备改性聚合物的条件为:单体占总质量的30%,乳化剂占油相的10%,亲水亲油平衡值(HLB)为6,引发剂占单体质量的0.2%,油水相比为1∶2。其黏均分子量为450×10^(4)g/mol。测试了该聚合物1.5%的浓度在120℃、170s^(-1)下剪切1.5h后黏度保持在80mPa·s,具有较好的耐温性,并具有剪切回复性能;其粒径分布为500~1200nm;在破胶剂过硫酸钾的用量为0.03%时,在90℃下,其黏度可以下降到5mPa·s,完成破胶。

齿轮齿廓抛光方法研究进展

齿轮是现代机械传动系统中运用最为广泛的传动件,齿轮齿廓的精度和表面质量对齿轮传动的精度、平稳性、可靠性和噪声影响巨大。齿轮的加工过程通常要经历初切齿—热处理—初磨—精磨等工艺过程,然而,经磨削加工后齿廓仍然存在磨削横纹、表面粗糙度难以进一步降低、表面粗糙度沿齿廓分布不均匀等问题。目前,齿轮经磨削后进行齿廓抛光是解决上述问题的有效途径之一。为此,将现有主要齿轮齿廓抛光方法归纳为齿廓电化学机械抛光、齿廓磨料流抛光、齿廓磁流变抛光以及齿廓剪切增稠抛光等4大类。详细阐述了当前主要齿轮齿廓抛光方法的加工原理;列举了各种加工方法的加工实例;从加工的适应范围、加工效率、抛光后的齿廓表面粗糙度的改善率以及对加工设备的要求等方面归纳了各个加工方法的技术优势和存在的问题。结果表明,使用其他辅助能场(如超声、激光、磁场等)与传统抛光方法复合以实现高效、高精度、高表面一致性齿廓抛光将是未来的主要研究方向。

基于MOF-801的高性能剪切增稠液的制备及防护性能研究

航空服作为保护飞行员安全的重要个人防护设备,一直在不断改进和升级。如何在保证飞行员生命健康的前提下,实现航空服穿戴舒适化和轻质化,一直都是一个亟须解决的问题。剪切增稠液是一种新型智能材料,其具有独特的非牛顿流体特性,可有效吸收外来冲击从而实现缓冲效果。然而,现有研究中剪切增稠液体系亟待进一步优化,传统二氧化硅基剪切增稠效应也需要提高。基于此,本文以氯化氧锆为次级构筑单元,富马酸为侨联配体,得到具有高度结晶度和良好热稳定性的MOF-801纳米颗粒。将其与乙二醇溶液通过球磨法制备得到剪切增稠液。该产品表现出优异的剪切增稠性能,在相同质量分数下其性能优于传统二氧化硅基的剪切增稠液。同时,利用激波发生装置,研究发现剪切增稠液在超高速激波作用下,同样表现出由液体向固体的转变。最后,通过稀释后抽滤方法,将剪切增稠液与天然皮革紧密复合,所得复合结构表现出良好的能量耗散特性和缓冲减震特点。MOF-801基剪切增稠液不仅具有优异的剪切增稠性能,也为新一代防护服的仿生轻质化设计提供了新的方向。

基于剪切增稠液的耗能器设计与性能分析

为增强非结构构件的抗振性能,文中基于约束阻尼形式以及新型阻尼材料STF,提出一种贴附式夹层耗能器。文中介绍耗能器的构造及工作原理并通过STF的增稠机理解释其减振耗能的可行性;其次通过数值模拟的方式研究耗能器中STF夹层厚度对其耗能性能的影响,得出在非结构构件的振动频率不同时,耗能器应选择适宜的夹层厚度,为非结构构件耗能减振提供了新思路。

STF复合高分子纤维材料传统体育防护用具开发研究

文章介绍了剪切增稠流体(STF)复合高分子纤维材料的特性和分类,分析了不同体系STF材料的剪切增稠机理,然后探究了在体育防护用具的开发中STF复合高分子纤维材料的应用优势,最后研究了该复合材料在具体的防护装备和防护外衣中的开发与应用。

成分比例和温度调控对剪切增稠液流变性能的影响

以粒径为350 nm的二氧化硅和聚乙二醇200为原料,通过球磨的方式将不同比例的二氧化硅和聚乙二醇进行充分混合后得到剪切增稠液,并从剪切应力、剪切速率与黏度方面分析剪切增稠液的流变特性,研究二氧化硅质量分数和温度对黏度的影响.结果表明,在一定范围内,随着纳米二氧化硅含量增加和温度的降低,剪切增稠液的整体黏度逐渐增加,临界剪切速率逐渐减小,更易触发剪切增稠机制.

剪切增稠流体增强尼龙纤维织物的防刺性能

研究了SiO2/PEG剪切增稠流体对尼龙纤维织物防刺性能的影响。研究结果表明,固相体积分数为10%的SiO2/PEG 400分散体系,具有典型的剪切增稠特性。经过SiO2/PEG 400剪切增稠流体处理的复合防刺纤维织物的防刺性能优于普通尼龙纤维织物。对纤维织物的显微损伤机制的研究表明,剪切增稠流体使尼龙纤维实现强化粘合,阻止纤维在高能量冲击下产生偏移,从而在纤维之间呈现高效率的能量转移。此类复合防刺纤维织物可用于制造穿着更舒适、防护性能更强的防刺服。

添加剂的含量和分子链长对剪切增稠液性能的影响

将二氧化硅颗粒和不同分子链长添加剂颗粒分散到聚乙二醇分散介质中制得剪切增稠液样品，研究了添加剂的不同含量和不同分子链长对剪切增稠液流变性能的影响．对其流变特性的研究表明，随着添加剂含量的增加和分子链长的增长，样品的剪切增稠效应增强明显，并用大粒子簇的形成对增强机理给出了合理的解释．