European Journal of Mechanics B-fluids最新文献_第7页

A three-dimensional level set method for two-phase electrohydrodynamics with finite electric Reynolds number 有限电雷诺数两相电流体力学的三维水平集方法

IF 2.5 3区工程技术 Q2 MECHANICS

European Journal of Mechanics B-fluids

Pub Date : 2025-10-14 DOI: 10.1016/j.euromechflu.2025.204389

Nabila Naz

The electrohydrodynamics (EHD) of droplets under electric fields underpins technologies from ink-jet printing and electrosprays to droplet sorting and microfluidics, yet accurate prediction remains challenging because most existing studies are confined to two-dimensional or axisymmetric models and often neglect surface-charge convection, a mechanism that strongly modifies interfacial stresses and breakup. To address this gap, we develop a fully three-dimensional (3D) level-set computational framework for leaky–dielectric two-phase flows that resolves bulk charge conservation, interfacial surface-charge convection, and topology change over a wide range of electric Reynolds numbers

R e_{E}

(the ratio of charge-relaxation to convection time) and electric capillary numbers

C a_{E}

(the ratio of electric stress to surface tension). Unlike existing three-dimensional studies that either neglect surface-charge convection or are restricted to small deformations without breakup, our framework provides a comprehensive 3D treatment of finite-

R e_{E}

charge convection, topology change, and breakup mapping. The method is carefully verified (mass conservation error

< 0.5 %

) and validated against Taylor’s small-deformation theory and silicone–castor oil experiments, confirming quantitative accuracy. Our simulations demonstrate that surface-charge convection redistributes interfacial charges, weakens EHD circulation, suppresses oblate deformation, and enhances prolate deformation; three-dimensional charge maps and two-dimensional cross-sectional contours quantify these effects in detail. For prolate drops, we capture and classify breakup transitions in full 3D — from end-pinching to conic cusping and ultimately tip streaming — and construct a comprehensive

(C a_{E}, R e_{E})

phase diagram. By integrating finite-

R e_{E}

effects, 3D surface-charge diagnostics, and breakup mapping in a validated computational method, this study establishes a novel predictive framework for electric-field-driven droplet technologies.

电场作用下液滴的电流体动力学（EHD）是喷墨打印、电喷雾、液滴分选和微流体等技术的基础，但准确的预测仍然具有挑战性，因为大多数现有研究局限于二维或轴对称模型，往往忽略了表面电荷对流，这是一种强烈改变界面应力和破裂的机制。为了解决这一差距，我们开发了一个全三维（3D）水平集计算框架，用于泄漏介质两相流，该框架解决了大量电荷守恒，界面表面电荷对流，以及在大范围内的电雷诺数ReE（电荷弛豫与对流时间之比）和电毛细数CaE（电应力与表面张力之比）的拓扑变化。现有的三维研究要么忽略了表面电荷对流，要么局限于没有破裂的小变形，而我们的框架提供了有限稀土电荷对流、拓扑变化和破裂映射的全面三维处理。该方法经过仔细验证（质量守恒误差<；0.5%），并与Taylor的小变形理论和硅-蓖麻油实验进行了验证，确认了定量准确性。模拟结果表明，表面电荷对流重新分配界面电荷，减弱EHD环流，抑制扁形变形，增强延伸变形；三维电荷图和二维截面轮廓详细量化了这些效应。对于长时间的液滴，我们捕获并分类了全3D的破裂转变-从末端挤压到圆锥锥形和最终的尖端流-并构建了一个全面的（CaE,ReE）相图。通过将有限稀土效应、三维表面电荷诊断和破裂映射集成到一种经过验证的计算方法中，该研究为电场驱动液滴技术建立了一个新的预测框架。

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引用次数: 0

Prolonging the life time of underground ice ring formed in the period of the cryogenic gas storage 延长低温储气期间形成的地下冰环的寿命

IF 2.5 3区工程技术 Q2 MECHANICS

European Journal of Mechanics B-fluids

Pub Date : 2025-10-14 DOI: 10.1016/j.euromechflu.2025.204395

Mustafa Turkyilmazoglu , Abdulaziz Alotaibi

Building upon a modified Karman–Pohlhausen technique, a recent study by Panfilov (2021) employed spherical coordinates to solve the heat transport problem in a heterogeneous domain surrounding a cavity storing cryogenic fluids underground. This analysis revealed the formation of an ice ring around the cavity, acting as a protective barrier against flooding from the stored material. This present work expands on that research by introducing heat generation and absorption into the media, aiming to analyze the temporal evolution of temperature and its impact on ice ring formation. Such heat exchange could be caused by seasonal fluctuations or geothermal activity. Motivated by these real-world influences, we extend the theoretical framework presented in Panfilov (2021) to investigate the universal evolution of the temperature field in the cavity, insulation, and rock regions. This study will track the emergence, persistence (dependent on heat balance), and eventual disappearance of the ice zone while determining its maximum thickness as a function of various parameters. We anticipate that heat generation will accelerate heat transfer between zones, reducing the perturbation length and consequently shortening the lifespan of the ice ring. Conversely, heat absorption will slow down thermal wave propagation by increasing the perturbation time length, thereby prolonging the freezing front of the ice ring and extending the life of both the ice crust and the cryogenic liquid within the underground cavity.

Panfilov（2021）最近的一项研究基于改进的Karman-Pohlhausen技术，采用球坐标解决了地下储存低温流体的空腔周围非均质区域的热传输问题。分析结果显示，在洞穴周围形成了一个冰环，作为防止储存物质泛滥的保护屏障。本研究在此基础上进行了扩展，将热的产生和吸收引入到介质中，旨在分析温度的时间演变及其对冰环形成的影响。这种热交换可能是由季节波动或地热活动引起的。受这些现实世界的影响，我们扩展了Panfilov（2021）提出的理论框架，以研究空腔、绝缘和岩石区域温度场的普遍演变。这项研究将跟踪冰带的出现、持续（取决于热平衡）和最终消失，同时确定其最大厚度作为各种参数的函数。我们预计热量的产生将加速区域之间的热传递，减少扰动长度，从而缩短冰环的寿命。反之，热吸收通过增加摄动时间长度来减缓热波传播，从而延长冰环冻结锋，延长冰壳和地下空腔内低温液体的寿命。

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引用次数: 0

A complete Helmholtz decomposition of second order horizontal velocity structure functions 二阶水平速度结构函数的完整亥姆霍兹分解

IF 2.5 3区工程技术 Q2 MECHANICS

European Journal of Mechanics B-fluids

Pub Date : 2025-10-14 DOI: 10.1016/j.euromechflu.2025.204394

Erik Lindborg

In recent years, several studies have been made in which atmospheric and oceanic data were used to decompose horizontal velocity statistics into a rotational component, associated with vertical vorticity, and a divergent component, associated with horizontal divergence. The decomposition methods rely on the assumption of statistical isotropy. In this paper, the full anisotropic equations relating the rotational, divergent and the rotational-divergent components of the second order velocity structure function tensor to the longitudinal, transverse and longitudinal–transverse components are formulated and solved analytically.

近年来进行了几项研究，利用大气和海洋资料将水平速度统计分解为与垂直涡度有关的旋转分量和与水平辐散有关的发散分量。分解方法依赖于统计各向同性的假设。本文建立了二阶速度结构函数张量的旋转、发散和旋转-发散分量与纵向、横向和纵向-横向分量的全各向异性方程，并对其进行了解析求解。

引用次数: 0

Effects of high-velocity flow and oxygen-lean conditions on autoignition of RP-3 aviation fuel 高速流动和贫氧条件对RP-3航空燃油自燃的影响

IF 2.5 3区工程技术 Q2 MECHANICS

European Journal of Mechanics B-fluids

Pub Date : 2025-10-11 DOI: 10.1016/j.euromechflu.2025.204392

Wenhui Zhai , Yuxin Fan , Wei Wang

In advanced afterburner systems, a high inflow temperature can induce thermal autoignition of fuel, resulting in undesirable temperature distributions and causing ablation of flameholders and fuel injection devices. To explore the thermal autoignition characteristics of RP-3 aviation fuel, experiments were conducted using a pressure-swirl atomizer with a forward fuel supply. Key operating parameters included inflow velocity (50–150 m/s), inflow temperature (1000–1200 K), oxygen content (10.5 %–14.1 %), and fuel–air ratio (0.04–0.06). The results indicate that the thermal release and dissipation of autoignition reactions are key factors influencing the autoignition length and mode. Increasing the inflow temperature and fuel–air ratio promotes greater thermal release, while higher flow velocity leads to increased thermal dissipation. When the thermal release is low (e.g., at 1000 K) or thermal dissipation is high (e.g., at 150 m/s and 1100 K), the autoignition mode exhibits randomness, and the flame structure shows a single peak. In cases of low thermal release, an inflow velocity greater than 100 m/s inhibits thermal occurrence. Conversely, with high thermal release (e.g., at 1200 K) or low thermal dissipation (50–100 m/s and 1100 K), the autoignition mode transitions from random to continuous, and the flame structure changes from unimodal to bimodal. Keeping other conditions constant, increasing the inflow temperature from 1000 K to 1200 K reduces the autoignition length by 7.3 %–56.8 %. Similarly, increasing the fuel–air ratio from 0.04 to 0.06 decreases the autoignition length by 12.5 %–49.5 %. On the other hand, raising the inflow velocity from 50 m/s to 150 m/s increases the autoignition length by 32.9 %–252.0 %.

在先进的加力燃烧室系统中，高流入温度会引起燃料的热自燃，导致不理想的温度分布，并导致火焰座和燃油喷射装置的烧蚀。为了研究RP-3航空燃油的热自燃特性，采用前向供油压力旋流喷雾器进行了实验。关键操作参数包括流入流速（50-150 m/s）、流入温度（1000-1200 K）、氧含量（10.5 % -14.1 %）和燃料空气比（0.04-0.06）。结果表明，自燃反应的热释放和热耗散是影响自燃长度和模式的关键因素。进气温度和燃料空气比的增加促进了更大的热释放，而流速的增加导致了更大的热耗散。当热释放低（如1000 K）或热耗散高（如150 m/s和1100 K）时，自燃模式表现为随机性，火焰结构表现为单峰。在低热释放的情况下，大于100 m/s的流入速度抑制热的发生。相反，当热释放高（如1200 K）或热耗散低（50-100 m/s和1100 K）时，自燃模式从随机转变为连续，火焰结构从单峰转变为双峰。在其他条件不变的情况下，将入流温度从1000 K提高到1200 K，可使自燃长度减少7.3 % ~ 56.8% %。同样，将燃料空气比从0.04增加到0.06，会使自燃长度减少12.5 % -49.5 %。另一方面，将来流速度从50 m/s提高到150 m/s，自燃长度增加32.9% % ~ 252.0 %。

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引用次数: 0

An improved weakly compressible multi-resolution SPH method for free-surface flow simulation 一种改进的弱可压缩多分辨率SPH自由表面流动模拟方法

IF 2.5 3区工程技术 Q2 MECHANICS

European Journal of Mechanics B-fluids

Pub Date : 2025-10-11 DOI: 10.1016/j.euromechflu.2025.204391

Zihao Zhao, Lingyun Tian, Xiaoyang Xu

This paper proposes an improved multi-resolution smooth particle hydrodynamics (SPH) method for efficiently and accurately simulating the free surface flow of viscous fluids. To address the numerical instabilities arising from interactions between coarse and fine particles due to differences in smoothing length, this study proposes a particle refinement method inspired by adaptive mesh refinement (AMR) and introduces a multi-layer background grid coupling mechanism to improve numerical accuracy while maintaining computational efficiency. To resolve physical field discontinuities at the interface between refined and non-refined regions due to the truncation of the smoothing kernel, buffer particles (including child guard and parent guard particles) are introduced on both sides of the refined region. The physical properties of hidden parent guard particles are updated by fine particles within the fine background grid, ensuring a smooth transition of physical quantities between coarse and fine particle regions. To mitigate tensile instability caused by irregular particle distribution, the particle shifting technique is further enhanced, improving the stability of multi-resolution simulations. Finally, comparisons with single-resolution simulations of dam-break flow, hydrostatic water column, and F-shaped cavity flow demonstrate that the proposed method significantly improves computational efficiency while maintaining high accuracy, thus confirming its effectiveness and robustness.

本文提出了一种改进的多分辨率光滑粒子流体力学（SPH）方法，用于高效、准确地模拟粘性流体的自由表面流动。针对细粒和粗粒之间由于平滑长度不同而产生的相互作用所带来的数值不稳定性，本研究提出了一种受自适应网格细化（AMR）启发的粒子细化方法，并引入多层背景网格耦合机制，在保持计算效率的同时提高数值精度。为了解决由于平滑核截断而导致的精细化和非精细化区域界面处的物理场不连续问题，在精细化区域两侧引入了缓冲粒子（包括子保护粒子和父保护粒子）。隐藏的母守护粒子的物理性质由细背景网格内的细粒子更新，确保了粗粒子和细粒子区域之间物理量的平稳过渡。为了减轻颗粒不规则分布引起的拉伸不稳定性，进一步加强了颗粒移动技术，提高了多分辨率模拟的稳定性。最后，通过与溃坝流、静压水柱流和f形空腔流的单分辨率模拟对比，表明本文方法在保持较高精度的同时，显著提高了计算效率，验证了其有效性和鲁棒性。

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引用次数: 0

Influences of particle-particle and particle-wall interactions on the settling behaviors of the centimeter-sized spherical particles 颗粒-颗粒和颗粒-壁相互作用对厘米级球形颗粒沉降行为的影响

IF 2.5 3区工程技术 Q2 MECHANICS

European Journal of Mechanics B-fluids

Pub Date : 2025-10-10 DOI: 10.1016/j.euromechflu.2025.204387

Lun Sun , Ri Zhang , Zhongwei Zhou , Jifu Yin , D.D. Meringolo

This paper experimentally investigates the effect of particle-particle and particle-wall interactions on the settling process of spherical particles. A convergence binocular calibration technique was used to capture the settling process under three typical conditions: (a) individual spherical particles settling at the center of the tank, (b) individual spherical particles settling near the wall, and (c) two symmetric spherical particles settling at the center of the tank. The ratio of initial particle-particle or particle-wall gap to the particle diameter is defined as a dimensionless parameter Gap. For individual particles released near the wall, when Gap is within 1.5, the wall significantly suppresses the random deflection characteristics typically observed for individual spherical particles settling at the tank center. Similarly, for two symmetric particles, random deflection is markedly suppressed, with highly symmetrical settling velocities and trajectories. The settling behavior of an individual spherical particle near the wall closely resembles that of the wall-facing particle in the symmetric-pair case, indicating that the wall effectively acts as a mirror. Additionally, Gap exerts little influence on the final mean settling velocity for either individual particles released near the wall or twin particles released at the center of the water tank.

本文通过实验研究了颗粒-颗粒和颗粒-壁相互作用对球形颗粒沉降过程的影响。采用会聚双目标定技术捕捉了三种典型条件下的沉降过程：(A)单个球形颗粒沉降在槽中心，(b)单个球形颗粒沉降在槽壁附近，(c)两个对称球形颗粒沉降在槽中心。初始颗粒-颗粒间隙或颗粒-壁间隙与颗粒直径之比定义为无量纲参数间隙。对于靠近壁面释放的单个颗粒，当间隙小于1.5时，壁面显著抑制了随机偏转特性，通常观察到单个球形颗粒沉降在罐中心。同样，对于两个对称粒子，随机偏转被明显抑制，具有高度对称的沉降速度和轨迹。靠近壁面的单个球形颗粒的沉降行为与对称对情况下面向壁面的颗粒的沉降行为非常相似，表明壁面有效地起着镜子的作用。此外，无论是在水箱壁面附近释放的单个颗粒还是在水箱中心释放的双颗粒，间隙对最终平均沉降速度的影响都很小。

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引用次数: 0

Study on the influence of the rotational degree of freedom on the heat transfer of single-y vibrating blunt bodies 转动自由度对单y振动钝体传热影响的研究

IF 2.5 3区工程技术 Q2 MECHANICS

European Journal of Mechanics B-fluids

Pub Date : 2025-10-10 DOI: 10.1016/j.euromechflu.2025.204388

Qingchun Zhou, Xiaowei Liu, Chunji Hu

Active rotation is commonly employed in traditional enhanced heat dissipation applications. However, passive rotation, which operates without external energy input, leverages environmental energy more effectively, showing great potential for enhanced heat transfer applications. This study explores the impact of passive rotation on the heat transfer characteristics of single-degree-of-freedom transverse vibrations in circular cylinders and square prisms. Numerical simulations were performed under the conditions of Re = 100, m* = 2, ζ = 0, and Pr = 0.7. The results show that the rotational degree of freedom has minimal influence on the heat transfer of circular cylinders, with only a 1.11 % increase in Nusselt number. In contrast, it significantly enhances heat transfer in square prisms, leading to a 14.21 % increase. Further analysis reveals that the rotational degree of freedom transitions the vibration mode from pure vortex-induced vibration (VIV) to a combination of VIV and galloping, which is the primary mechanism behind the heat transfer enhancement. Flow field analysis indicates that this transition strengthens vortex intensity and disturbs the thermal boundary layer, providing a microscopic explanation for the observed heat transfer improvements. The introduction of rotational freedom in such systems offers a novel and effective approach to enhance heat transfer performance.

主动旋转通常用于传统的增强散热应用。然而，被动旋转在没有外部能量输入的情况下运行，更有效地利用环境能量，显示出增强传热应用的巨大潜力。本研究探讨了被动旋转对圆柱和方棱镜单自由度横向振动传热特性的影响。在Re = 100,m* = 2,ζ = 0,Pr = 0.7的条件下进行了数值模拟。结果表明：转动自由度对圆柱换热的影响最小，努塞尔数仅增加1.11 %；相比之下，它显著提高了方棱镜的传热，导致14.21% %的增加。进一步分析表明，旋转自由度将振动模式从单纯的涡激振动转变为涡激振动和驰骋振动的结合，这是传热增强的主要机制。流场分析表明，这种转变增强了涡旋强度，扰乱了热边界层，为观察到的传热改善提供了微观解释。在这种系统中引入旋转自由为提高传热性能提供了一种新颖有效的方法。

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引用次数: 0

Impact of temperature dependent viscosity on thermo-bioconvective flow of Jeffrey fluid containing gravitactic microorganism in a permeable medium 温度依赖粘度对含重力微生物的Jeffrey流体在可渗透介质中热生物对流的影响

IF 2.5 3区工程技术 Q2 MECHANICS

European Journal of Mechanics B-fluids

Pub Date : 2025-10-09 DOI: 10.1016/j.euromechflu.2025.204386

Dhananjay Yadav , Houda Al Maqbali , Mukesh Kumar Awasthi , Ravi Ragoju , Saif Al Aghbari , Maryam Al Aameriya , Basama Al Hanai , Asma Al Malki , Ljina Al Aamri

This study investigates how linear and exponential variations in temperature-dependent viscosity influence the initiation of thermo-bioconvective flow in a non-Newtonian Jeffrey fluid with gravitactic microorganisms present in a permeable medium, which has not been addressed in the existing literature. The threshold of the thermo-bioconvective flow, taking into account the absence of microorganism flux at the boundaries, is determined through linear stability theory, and the corresponding eigenvalue problem is resolved analytically using the Galerkin method. The findings indicate that when viscosity changes linearly with temperature, the critical Rayleigh number

R_{D, c}^{E x}

at which the system starts convection is approximately 11 % higher than when viscosity changes exponentially with temperature. This shows that the system is more unstable when viscosity changes exponentially with temperature compared to a linear change. The stability of the arrangement decreases as the bio Rayleigh-Darcy number

R_{B D}

, the bio Péclet number

P e_{B}

, the Jeffrey factor

γ

, and the viscosity deviation parameter

F

increase. In instances of exponential viscosity variation with temperature, the size of the convective cells grows with the viscosity deviation parameter

F

, while it remains constant in the case of linear viscosity variation. Additionally, it is important to emphasize that oscillatory convective motion is not relevant to the current analysis.

本研究探讨了温度依赖性粘度的线性和指数变化如何影响存在于可渗透介质中的重力微生物的非牛顿杰弗里流体中热生物对流流动的启动，这在现有文献中尚未得到解决。考虑边界处不存在微生物通量，通过线性稳定性理论确定热生物对流的阈值，并利用伽辽金方法解析求解相应的特征值问题。结果表明，当粘度随温度呈线性变化时，系统开始对流的临界瑞利数rd，cEx比粘度随温度呈指数变化时高约11%。这表明，当粘度随温度呈指数变化时，与线性变化相比，系统更不稳定。随着生物瑞利-达西数rbd、生物psm - clet数peb、Jeffrey因子γ和粘度偏差参数f的增大，排列的稳定性降低。在粘度随温度呈指数变化的情况下，对流单元的尺寸随着粘度偏差参数f的增大而增大，而在粘度线性变化的情况下，对流单元的尺寸保持不变。此外，重要的是要强调振荡对流运动与当前的分析无关。

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引用次数: 0

Heat transfer from a partially buried circular cylinder in oscillatory flow 振荡流动中部分埋置圆柱的传热

IF 2.5 3区工程技术 Q2 MECHANICS

European Journal of Mechanics B-fluids

Pub Date : 2025-10-09 DOI: 10.1016/j.euromechflu.2025.204384

H. Thomas , R. Stuhlmeier , A.G.L. Borthwick , S. Michele

With the growing abundance of man-made cylindrical structures located on or close to the seabed, it is important to be able to assess their potential environmental impact. Herein, a model is presented of the viscous-thermal boundary layer in the vicinity of a circular cylinder resting on, or partially buried in, an otherwise flat seabed. To model the influence of wave-induced motions near such a cylinder, we assume oscillatory flow in which the water particle displacements are small with respect to the cylinder radius. A perturbation expansion is utilised to derive solutions of the boundary layer equations, leading to analytical solutions at multiple orders. The unsteady temperature field for various burial depths is then determined numerically using a Crank–Nicolson scheme, and quantitative results, such as the Nusselt number at the cylinder surface, are deduced. Both diffusion and steady convection are responsible for the unsteady transport of temperature. The dynamics of the convective field enhance overall heat transfer from the cylinder and lead to the temperature being transported radially outward near to the seabed.

由于在海床上或靠近海床的人造圆柱形结构越来越多，因此能够评估其潜在的环境影响是很重要的。本文提出了一个基于或部分埋在平坦海床上的圆柱附近的粘热边界层模型。为了模拟这种圆柱体附近波动引起的运动的影响，我们假设振荡流，其中水粒子的位移相对于圆柱体半径来说很小。利用微扰展开导出边界层方程的解，得到多阶解析解。然后采用Crank-Nicolson格式对不同埋深下的非定常温度场进行数值计算，并推导出圆柱表面的努塞尔数等定量结果。温度的非定常输运是由扩散和定常对流共同造成的。对流场的动力学增强了圆柱体的整体传热，并导致温度径向向外输送到海床附近。

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引用次数: 0

Stabilization of drug droplet contact line via Bovine Serum Albumin Solution-Phase Additive 用牛血清白蛋白溶液添加剂稳定药滴接触线

IF 2.5 3区工程技术 Q2 MECHANICS

European Journal of Mechanics B-fluids

Pub Date : 2025-10-08 DOI: 10.1016/j.euromechflu.2025.204385

Josías N. Molina-Courtois , Roxana Belen Pérez Hidalgo , Yojana J.P. Carreón , Carlos A. Martínez-Miwa , Lourdes Díaz-Jiménez , Mario Castelán , Jorge González-Gutiérrez

The method of pattern analysis in dried droplets has emerged as an effective tool for detecting adulterants in medications and diagnosing pathologies. However, despite numerous studies on the drying dynamics of droplets, there remains a need for effective methods to stabilize droplet contact line and achieve controlled coating. Finding alternative solutions for droplet stabilization could significantly improve the precision and efficacy in the application of the dry droplet pattern recognition method. In this study, we hypothesize that bovine serum albumin (BSA) can act as an effective tool for stabilizing the contact line of sessile methotrexate (MTX) drops, controlling pattern formation during the drying process. We evaluated BSA concentrations of 0.01, 0.1, 0.25, 0.5, 1, and 2% in MTX (10%) solutions; which, in the absence of BSA, become destabilized on polymethylmethacrylate (PMMA) substrates. Our results indicate that, starting from a concentration of 0.1% BSA, the methotrexate droplets are efficiently fixed, producing highly reproducible patterns. Using measurements of height profile, contact angle, and evaporation time, we found that BSA fixes the droplets and prevents the deformation of the contact line. Additionally, we observed that BSA modifies the interaction between the droplet and the substrate, improving adhesion and reducing the expansion or contraction of the droplets. Importantly, the stabilizing effect was only observed when BSA was present in solution; when BSA was pre-adsorbed onto the substrate, MTX droplets exhibited spreading and destabilization. We demonstrated that BSA promotes a homogeneous distribution of solutes and more uniform and controlled evaporation when acting as a solution-phase additive in MTX formulations. These findings indicate that BSA can serve as a functional modulator for enhancing reproducibility and controlling deposition in dropwise manufacturing of pharmaceutical coatings.

干燥液滴的模式分析方法已成为检测药物掺假和诊断病理的有效工具。然而，尽管对液滴的干燥动力学进行了大量的研究，但仍然需要有效的方法来稳定液滴接触线并实现受控涂层。寻找稳定液滴的替代方案可以显著提高干液滴模式识别方法的应用精度和效率。在这项研究中，我们假设牛血清白蛋白（BSA）可以作为一种有效的工具来稳定无柄甲氨蝶呤（MTX）滴剂的接触线，控制干燥过程中的模式形成。我们评估了MTX（10%）溶液中BSA浓度为0.01、0.1、0.25、0.5、1和2%的情况；在没有BSA的情况下，在聚甲基丙烯酸甲酯（PMMA）底物上变得不稳定。我们的研究结果表明，从0.1%的BSA浓度开始，甲氨蝶呤液滴被有效地固定，产生高度可重复性的图案。通过测量高度轮廓、接触角和蒸发时间，我们发现BSA可以固定液滴并防止接触线变形。此外，我们观察到BSA改变了液滴与基质之间的相互作用，改善了液滴的粘附性，减少了液滴的膨胀或收缩。重要的是，只有当BSA存在于溶液中时才观察到稳定效果；当BSA被预吸附到底物上时，MTX液滴表现出扩散和不稳定。我们证明，BSA促进溶质均匀分布和更均匀和控制蒸发时，作为一个溶液相添加剂在MTX配方。这些研究结果表明，BSA可以作为一种功能性调节剂，用于提高药物涂料的可重复性和控制沉积。

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引用次数: 0