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溶质梯度诱导悬浮液滴自驱动的数值模拟研究

力学学报 2024年第5期56卷 1223-1232页

作者：李祥伟郝浩浩谭唤书南方科技大学力学与航空航天工程系多组分流体实验室复杂流动及软物质研究中心广东深圳518055

悬浮液滴在溶质浓度梯度下会发生自发的移动.其原因是液滴界面处的非均匀分布溶质会使得流体界面上出现界面张力梯度,诱发界面流动.该过程涉及自驱动液滴的界面移动、界面附近流场与溶质浓度场的演化,以及多物理场的耦合效应.认识和理... 详细信息

悬浮液滴在溶质浓度梯度下会发生自发的移动.其原因是液滴界面处的非均匀分布溶质会使得流体界面上出现界面张力梯度,诱发界面流动.该过程涉及自驱动液滴的界面移动、界面附近流场与溶质浓度场的演化,以及多物理场的耦合效应.认识和理解这一复杂动力学过程具有一定的基础科学意义.文章通过联合守恒型Allen-Cahn方程、不可压Navier-Stokes方程和溶质的对流扩散方程,构建了一套能够描述溶质梯度诱导液滴自驱动现象的多相-多组分流体数值模型.通过算例对照和理论对比(静置液滴的拉普拉斯压差、浮力驱动的气泡上升和溶质浓度驱动液滴的迁移)验证了数值模型的准确性.模拟并研究了不同Marangoni数下溶质Marangoni效应诱导的双液滴融合或分离现象.结果表明,液滴的尺寸越大,移动速度越快,且增大Marangoni数使得自驱动液滴界面传质从扩散主导转变为对流主导,增强了液滴移动对环境溶质场的影响,进而推迟两液滴的融合发生时刻或者减小两者的分离速度.为后续解决多相-多组分流体系统中的物理问题提供了一套可靠的数值模型,为多组分微液滴操控提供了参考数据.

关键词：多组分自驱动液滴 Marangoni界面流动相场模型

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短波中标称伴流场特性分析

上海交通大学学报 2019年第2期53卷 170-178页

作者：郭春雨刘恬赵庆新郝浩浩哈尔滨工程大学船舶工程学院哈尔滨150001 哈尔滨工业大学能源科学与工程学院哈尔滨150001

以KCS标准船型为研究对象,采用RANS(Reynolds Averaged Navier-Stokes)方法对KCS约束模型在规则短波航行下标称伴流场进行了数值计算,并针对标称伴流场在短波中时历周期性变化的规律和特性进行了分析.计算结果表明:短波顶浪下的轴向标... 详细信息

以KCS标准船型为研究对象,采用RANS(Reynolds Averaged Navier-Stokes)方法对KCS约束模型在规则短波航行下标称伴流场进行了数值计算,并针对标称伴流场在短波中时历周期性变化的规律和特性进行了分析.计算结果表明:短波顶浪下的轴向标称伴流分数满足与入射波相似的周期性变化规律,单个波浪遭遇周期下的波浪伴流分数变化占比相对较小,但影响不可忽略;波浪伴流分数为负值时其主要原因为流体质点发生沿波浪传递方向的波漂移,其值近似为总平均流量;当波峰波谷位于螺旋桨盘面处时,轴向标称伴流场变化最为明显,且变化程度受波陡影响最大,而波长的减小对桨盘面下方区域的影响更为明显.

关键词：标称伴流场短波伴流分数波浪伴流场质量迁移数值计算

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固有周期下阻尼板对半潜式平台阻尼的影响

哈尔滨工程大学学报 2018年第5期39卷 831-836页

作者：韩端锋郝浩浩高良田刘恬刘峰哈尔滨工程大学船舶工程学院黑龙江哈尔滨150001

为了研究半潜式平台在固有周期下的自由衰减运动,本文基于重叠网格技术的计算流体力学(CFD)方法对半潜式平台垂荡、横摇和纵摇自由衰减运动进行数值模拟。利用该方法分别研究了不同初始衰减位置下,阻尼板宽度和厚度对半潜式平台垂荡、... 详细信息

为了研究半潜式平台在固有周期下的自由衰减运动,本文基于重叠网格技术的计算流体力学(CFD)方法对半潜式平台垂荡、横摇和纵摇自由衰减运动进行数值模拟。利用该方法分别研究了不同初始衰减位置下,阻尼板宽度和厚度对半潜式平台垂荡、横摇和纵摇阻尼的影响规律,并从流场角度分析了阻尼板的作用机理,通过与实验数据对比,验证该方法的准确性。研究结果表明:平台运动幅度越大,阻尼板起到的抑制作用越强,阻尼板边缘处的流动分离是平台阻尼增加的直接原因;阻尼板宽度与平台垂荡、横摇及纵摇阻尼呈正相关,而阻尼板厚度与其呈负相关。

关键词：半潜式平台阻尼板宽度厚度自由衰减运动阻尼流动分离重叠网格

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微槽道式热管模块散热特性实验研究

低温与超导 2022年第9期50卷 54-58,64页

作者：蒋昊辰张亚平郝昊昊西安科技大学能源学院西安710054

为解决大功率集成电路热点集中问题,设计了一种与针肋散热器一体化集成的微槽道式热管模块,分别改变了风速、散热器肋片尺寸、热源功率及热管表面温度均匀性,探究了该模块的散热特性。实验结果表明,在该实验工况下,散热器肋高20 mm时模... 详细信息

为解决大功率集成电路热点集中问题,设计了一种与针肋散热器一体化集成的微槽道式热管模块,分别改变了风速、散热器肋片尺寸、热源功率及热管表面温度均匀性,探究了该模块的散热特性。实验结果表明,在该实验工况下,散热器肋高20 mm时模块热扩散性能最佳,温度变化速率高出对照实验组约4℃/min;随着热流密度增加,热管能快速启动运行,该热管模块可正常运行的最大热流密度达到4.8 W/cm^(2),热管蒸发端与冷凝端最大温差达22℃,热管冷凝面端温差在3℃以内。表明该微槽道式热管模块能够最大限度避免基板的热应力集中,有效提高电路器件抵抗局部热冲击的性能,保证电路功率模块的高效平稳运行。

关键词：平板热管微型槽道散热特性热源功率

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液冷服冷源优化及性能参数研究

低温与超导 2022年第12期50卷 33-39页

作者：郝昊昊张亚平蒋昊辰西安科技大学能源学院西安710054

为延长液冷服的有效使用时间,提出一种使用高吸水性树脂(SAP)作为冷源的液冷服。在高温气候室中进行测试,探究液冷服对受试者皮肤温度及主观评价的影响。使用数值模拟探究环境温度、流量和人体代谢率对冷却服性能的影响,以及最佳工况组... 详细信息

为延长液冷服的有效使用时间,提出一种使用高吸水性树脂(SAP)作为冷源的液冷服。在高温气候室中进行测试,探究液冷服对受试者皮肤温度及主观评价的影响。使用数值模拟探究环境温度、流量和人体代谢率对冷却服性能的影响,以及最佳工况组合。结果表明:SAP能够延长液冷服的有效使用时间,与冰袋相比增长了37.5%,改善了受试者的主观评价;当环境温度和劳动强度增加时,改变进口温度比降低流速对皮肤温度有着更好的改善;在中度劳动下,20℃的进口温度与500 mL/min流量为最佳组合。

关键词：液冷服热应激热舒适相变蓄冷仿真模拟

Late Paleozoic to early Mesozoic volcanic-sedimentary history of the southeastern margin of the Central Asian Orogenic Belt: Timing of uplift of the Inner Mongolia paleo-uplift

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Science China Earth Sciences 2025年第1期68卷 297-309页

作者： Wenxing hao Jin-Hui YANG Guang ZHU State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences School of Resource and Environmental Engineering Hefei University of Technology

The Kulun region is located in the eastern Bainaimiao arc belt on the southeastern margin of the Central Asian Orogenic Belt(CAOB), adjacent to the North China Craton(NCC) to the south. This region records the closure of the PaleoAsian Ocean during the Paleozoic to early Mesozoic and is key to study the tectonic evolution of the northern margin of the *** conducted zircon U-Pb geochronology and Hf isotope analysis of volcanic-sedimentary and intrusive rocks in the Kulun region. The volcanic-sedimentary rocks were previously assigned an early Carboniferous age, but include volcanic rocks with ages of 267–266 Ma and sedimentary rocks with youngest detrital zircon age peaks of 265–244 Ma, which were intruded by a granite with an age of 242 Ma. This indicates that these rocks are actually middle Permian to Middle Triassic in age(267–242Ma) and correspond to the Qingfengshan and Liujiagou formations. Moreover, two volcanic rock samples have high εHf(t) values(+1.6 to +16.1) and relatively young two-stage Hf model ages(1095–327 Ma), indicating their sources associated with the CAOB. The age spectra and Hf isotopic characteristics of detrital zircons from the sedimentary rocks suggest that, during the middle Permian to Middle Triassic, the sedimentary provenance in the Kulun region was mainly the CAOB. However, by the Early Jurassic, the provenance changed to the NCC(i.e., the Inner Mongolia Paleo-uplift, IMPU). This result, combined with the development of a series of conglomerates on the northern margin of the NCC in the Late Triassic(i.e., Xingshikou, Xiaoyingzi,and Xiaohekou formations), indicates the Kulun region experienced an abrupt change in paleogeography during the Late Triassic, with the IMPU undergoing significant uplift and thus becoming the main sediment source in the Kulun region. Based on the Late Triassic alkaline igneous belt(235–215 Ma) in the IMPU, we speculate that this uplift was caused by detachment of the southward-subducting Paleo-Asian oceanic

关键词： Central Asian Orogenic Belt the North China Craton Zircon geochronology Hf isotopes Inner Mongolia Paleo-uplift

Preparation of Low Ratio Magnesium Ccement by Acid Leaching Treatment of Boron Mud

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 120-129页

作者： YANG Mei ZHANG Mingzhe CHEN hao School of Materials Science and Engineering Shenyang Jianzhu UniversityShenyang 110168China School of Physical Science and Technology Shenyang Normal UniversityShenyang 110168China

The effects of liquid-solid ratio and reaction time on the leaching rate of magnesium at room temperature were investigated,as well as the effects of the molar ratio of MgO/MgCl_(2),the amount of water added,and the amount of acid-impregnated slag dosed on the compressive strength and water resistance of *** results showed that the magnesium element in the boron mud could be maximally leached under the conditions of 1:1 concentration of hydrochloric acid at room temperature,liquid-solid ratio of 2.5 mL·g^(-1),and reaction time of 5 h,and the main products were amorphous SiO_(2) as well as a small amount of magnesium olivine which had not been completely *** LR-MOC prepared using the acid-soaked mixture could reach a softening coefficient of 0.85 for 28 d of water immersion when the molar ratio of MgO/MgCl_(2) was 2.2,the amount of water added was 0 g,and the acid-soaked slag dosing was 40 wt%,which also led to an appreciable late-strength,with an increase of 19.4%in compressive strength at 28 d compared to that at 7 *** previous studies,LR-MOC prepared in this way has a final strength phase that is not the more easily hydrolysed 3-phase but the lath-like *** this phenomenon,we analyzed the mechanism and found that,during the acid leaching process,a part of amorphous SiO_(2) dissolved in the acid leaching solution formed a silica sol,in which Mg^(2+)played a bridging role to make the silica sol more *** the addition and hydrolysis of MgO,the silica sol gel coagulation slows down,providing a capping layer to inhibit the hydrolysis of the 5-phase crystals and providing some strength after *** amorphous SiO_(2) in the other part of the acid-impregnated slag generated M-S-H gel with Mg^(2+)and OH-,which synergised with the dense structure composed of interlocking crystals to improve the water resistance of LR-MOC.

关键词： boron mud magnesium chloride-oxygen cement acid immersion water resistance silica sol

The role of axon guidance molecules in the pathogenesis of epilepsy

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Neural Regeneration Research 2025年第5期20卷 1244-1257页

作者： Zheng Liu Chunhua Pan hao Huang Department of Neurology Affiliated Hospital of Zunyi Medical UniversityZunyiGuizhou ProvinceChina

Current treatments for epilepsy can only manage the symptoms of the condition but cannot alter the initial onset or halt the progression of the disease. Consequently, it is crucial to identify drugs that can target novel cellular and molecular mechanisms and mechanisms of action. Increasing evidence suggests that axon guidance molecules play a role in the structural and functional modifications of neural networks and that the dysregulation of these molecules is associated with epilepsy susceptibility. In this review, we discuss the essential role of axon guidance molecules in neuronal activity in patients with epilepsy as well as the impact of these molecules on synaptic plasticity and brain tissue remodeling. Furthermore, we examine the relationship between axon guidance molecules and neuroinflammation, as well as the structural changes in specific brain regions that contribute to the development of epilepsy. Ample evidence indicates that axon guidance molecules, including semaphorins and ephrins, play a fundamental role in guiding axon growth and the establishment of synaptic connections. Deviations in their expression or function can disrupt neuronal connections, ultimately leading to epileptic seizures. The remodeling of neural networks is a significant characteristic of epilepsy, with axon guidance molecules playing a role in the dynamic reorganization of neural circuits. This, in turn, affects synapse formation and elimination. Dysregulation of these molecules can upset the delicate balance between excitation and inhibition within a neural network, thereby increasing the risk of overexcitation and the development of epilepsy. Inflammatory signals can regulate the expression and function of axon guidance molecules, thus influencing axonal growth, axon orientation, and synaptic plasticity. The dysregulation of neuroinflammation can intensify neuronal dysfunction and contribute to the occurrence of epilepsy. This review delves into the mechanisms associated with

关键词： axon guidance drug-resistant epilepsy epilepsy nerve regeneration nervous system diseases neural pathways neuroinflammatory diseases neuronal plasticity neurons synaptic remodeling

基于熵权TOPSIS法的甘肃省农产品物流能力评价研究

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物流科技 2024年第15期47卷 10-13页

作者：郝浩浩段小红甘肃农业大学财经学院甘肃兰州730070

为了科学地评价甘肃省农产品物流能力,文章采用了熵权TOPSIS法,选取了与甘肃省农产品物流能力相关的10项指标构建评价体系,从时间与空间两个角度来评价农产品物流能力。纵向上,选取甘肃省2012—2021年相关统计数据,对甘肃省农产品物流... 详细信息

为了科学地评价甘肃省农产品物流能力,文章采用了熵权TOPSIS法,选取了与甘肃省农产品物流能力相关的10项指标构建评价体系,从时间与空间两个角度来评价农产品物流能力。纵向上,选取甘肃省2012—2021年相关统计数据,对甘肃省农产品物流能力进行整体评价分析;横向上,选取甘肃省14个市(州)作为研究对象,借助2021年统计数据进行对比分析。评价结果显示:2012-2021年甘肃省农产品物流能力从非常不协调状态过渡到了一般协调状态,但各个市(州)的农产品物流能力发展不平衡。最后根据农产品物流能力评价结果提出相应对策。

关键词：熵权 TOPSIS 农产品物流能力