Acta Mechanica Sinica最新文献

{"title":"How initial release styles shape the locomotion and hydrodynamic behavior of a self-propelled fin in unsteady wakes","authors":"Peng Han \u0000 (,&nbsp;),&nbsp;Yu-Hang Qiu \u0000 (,&nbsp;),&nbsp;Dong Zhang \u0000 (,&nbsp;),&nbsp;Jun-Duo Zhang \u0000 (,&nbsp;),&nbsp;Wei-Xi Huang \u0000 (,&nbsp;)","doi":"10.1007/s10409-026-51017-x","DOIUrl":"10.1007/s10409-026-51017-x","url":null,"abstract":"<div><p>Living fish may suddenly encounter obstacles, join the queue of a fish school, or detect upstream flow in advance, leading to interactions with environmental flows that can either occur abruptly or develop gradually from an initial state. This study aims to address, from a hydrodynamic perspective, the extent to which the initial conditions can influence the locomotion characteristics of fish. We numerically investigate the effects of different initial gaps, release styles, and flow fields (quiescent flow fields and fully developed unsteady flows) on fish swimming in unsteady wakes generated by both upstream bluff bodies (avoidance phenomena) and leading swimming fish (schooling phenomena). The study employs a self-propelled flexible fin model for the swimming fish, direct simulation techniques for fluid flow, and the immersed boundary method for fluid-structure interactions. The results indicate that fish in schooling phenomena are more resilient to initial conditions compared to those in avoidance phenomena. Notably, while different release styles can alter locomotion in avoidance phenomena, the effects of these styles become negligible when simulations start from a fully developed flow field, which more accurately reflects natural conditions. In summary, contrary to the existing view, our findings demonstrate that with more realistic settings, initial release styles have limited effects on the hydrodynamic behavior of a self-propelled fin in unsteady wakes generated by both avoidance and schooling phenomena.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":7109,"journal":{"name":"Acta Mechanica Sinica","volume":"42 12","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148926955","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimal design of a bioinspired micropillar arrayed surface for equal load sharing and robust adhesion","authors":"Yonggui Cheng \u0000 (,&nbsp;),&nbsp;Randong Zuo \u0000 (,&nbsp;),&nbsp;Shize Hong \u0000 (,&nbsp;),&nbsp;Zhilong Peng \u0000 (,&nbsp;),&nbsp;Shaohua Chen \u0000 (,&nbsp;)","doi":"10.1007/s10409-026-51232-x","DOIUrl":"10.1007/s10409-026-51232-x","url":null,"abstract":"<div><p>Simultaneous detachment of all microstructures during the loading process, known as equal load sharing (ELS), can ensure the robust adhesion of a microstructural surface. Inspired by gecko adhesion, although various fibrillar structured surfaces had been fabricated to mimic gecko adhesion, robust adhesion is not easily achieved because of the load concentration at the edge fibrils of the microstructural surface. In this paper, an optimal design strategy is proposed to analyze the factors affecting the interface adhesion. It is found that the height, radius, and elastic modulus of the micropillars and the elastic modulus of the backing layer can be well optimized into specific non-uniform distributions, achieving ELS of all the micropillars at interface detachment, thereby leading to robust adhesion of micropillar arrayed surfaces. Furthermore, the non-uniform distribution functions of the micropillar’s height, radius, and Young’s modulus are well achieved analytically and verified by the finite element simulations. The proposed optimal design methods can also be applied to other fibrillar geometries, for example, mushroom-shaped fibrillar arrays. The obtained results would be very helpful for the design of robust adhesion of gecko-inspired microstructural adhesives.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":7109,"journal":{"name":"Acta Mechanica Sinica","volume":"42 12","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148927200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Loading curve characterization and pile-up/sink-in parameters determination for instrumented spherical indentation test on strain-hardening metallic materials","authors":"Xiaofei Zheng \u0000 (,&nbsp;),&nbsp;Shouming Zhao \u0000 (,&nbsp;),&nbsp;Xiaoyu Fu \u0000 (,&nbsp;),&nbsp;Weifeng Jiang \u0000 (,&nbsp;),&nbsp;Guangjian Peng \u0000 (,&nbsp;),&nbsp;Taihua Zhang \u0000 (,&nbsp;)","doi":"10.1007/s10409-026-51203-x","DOIUrl":"10.1007/s10409-026-51203-x","url":null,"abstract":"<div><p>Instrumented spherical indentation test is currently a mainstream research method for identifying the plastic parameters of metallic materials. Since only indentation load and depth are directly measurable, the shape characteristics of the indentation load-depth curve become crucial for the identification of material properties. In this study, indentation tests are performed on ten common metallic materials, revealing distinct types of loading curve shapes. By analyzing finite element simulation results for both linear-elastic power-law hardening and linear-elastic linear hardening materials, the indentation loading curves are classified into three types: concave, S-shaped (convex-to-concave), and convex. These shapes are primarily governed by the plastic parameters of the materials. Through analytical studies based on the extended Meyer’s law, the Meyer exponent is selected as the reliable characterization parameter for the loading curve shapes. Based on the relationships between plastic parameters and curve shape characteristics, demarcation lines are defined for shape type classification. Furthermore, relationships among multiple indentation analysis parameters are investigated, and a linear relationship is revealed between the measurable Meyer exponent and the pile-up/sink-in deformation parameter. This framework enables a novel methodology to determine the true contact depth and true contact area directly from the loading curve, providing a practical approach to identify pile-up/sink-in behavior of the material without requiring additional microscopic observation.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":7109,"journal":{"name":"Acta Mechanica Sinica","volume":"42 12","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148926956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Discussion on the classification of instability and critical load inspired by creasing and slightly curved beams under compression","authors":"Pengfei Yang \u0000 (,&nbsp;),&nbsp;Bin Liu \u0000 (,&nbsp;)","doi":"10.1007/s10409-026-51116-x","DOIUrl":"10.1007/s10409-026-51116-x","url":null,"abstract":"<div><p>This study proposes a novel approach for identifying instability types through systematic analysis of the characteristics of state and energy curves. Four distinct types of instability are identified: (i) finite energy-drop instability, (ii) infinitesimal energy-drop instability, (iii) stiffness drop instability, and (iv) perturbation-induced energy transition instability. This classification is established through systematic examination of state curve nonsmoothness (including kink points and jump points), loading/unloading path consistency, and corresponding energy barrier features in the energy curves. Notably, this approach reveals significant differences between creasing instability and conventional instability phenomena. The influence of initial geometric imperfections on instability characteristics is also investigated. While jump points in state curves demonstrate remarkable robustness against geometric imperfections, kink points will disappear for such imperfections. Three definitions of critical instability load are proposed for practical structures with imperfections and perturbations. The abrupt critical load, associated with jump/kink points on the state curve, conforms to classic theory but is overly idealized. The multivalueemergent critical load, marking the onset of multi-equilibrium states, is much more robust. It ensures safety yet is overly conservative. Energy barrier-based critical load, incorporating external perturbation energy and inter-equilibrium energy barriers, balances safety and efficiency. This work provides a targeted tool for engineers to select critical load definitions based on structural imperfections and perturbation conditions.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":7109,"journal":{"name":"Acta Mechanica Sinica","volume":"42 11","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148926960","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Protective performance of artificial cartilage foam metamaterials on human hip considering the strain rate effect","authors":"Jialong Luo \u0000 (,&nbsp;),&nbsp;Huifeng Xi \u0000 (,&nbsp;),&nbsp;Shiqing Huang \u0000 (,&nbsp;),&nbsp;Bowei Wang \u0000 (,&nbsp;),&nbsp;Xiqiao Feng \u0000 (,&nbsp;)","doi":"10.1007/s10409-026-25169-x","DOIUrl":"10.1007/s10409-026-25169-x","url":null,"abstract":"<div><p>Hip fractures represent a major public health concern among the elderly, primarily arising from falls, particularly lateral falls. Hip protectors have been demonstrated to reduce the risk of hip fractures. This study builds a new and more accurate human protection evaluation method to better assess the protective effect of hip protectors, discovers a novel hip protection material, namely artificial cartilage foam materials (ACF), and explores its protective effects during lateral falls. The results highlight the necessity for simulation models to incorporate the material’s strain rate effects. Furthermore, a comparative analysis of hip protection products with different densities and thicknesses indicates that, for a given thickness, there exists an appropriate density for hip protectors. As the thickness increases, the protective effect gradually enhances and stabilizes after reaching a specific thickness. Specifically, the ACF18 hip protector with 15 mm has been proven to significantly reduce the peak forces of the femoral neck and greater trochanter during falls, dropping to 4070 and 1867 N, respectively, with a reduction in peak forces of 47.05% and 68.63%. These findings provide important evidence for optimizing the design of hip protectors and help reduce the risk of femoral fractures caused by falls in the elderly.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":7109,"journal":{"name":"Acta Mechanica Sinica","volume":"42 12","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148927075","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Self-adaptive metamaterial plate enabling asymmetric wave propagation for crack detection","authors":"Zheng-Yang Li \u0000 (,&nbsp;),&nbsp;Yanzheng Wang \u0000 (,&nbsp;),&nbsp;Kai Wang \u0000 (,&nbsp;),&nbsp;Jun Wu \u0000 (,&nbsp;),&nbsp;Dongjia Yan \u0000 (,&nbsp;),&nbsp;Weiqiu Chen \u0000 (,&nbsp;),&nbsp;Chuanzeng Zhang \u0000 (,&nbsp;)","doi":"10.1007/s10409-026-51095-x","DOIUrl":"10.1007/s10409-026-51095-x","url":null,"abstract":"<div><p>Wave-based structural health monitoring (WSHM) methods employing metamaterials have attracted significant attention from both industry and academia. However, leveraging metamaterials with asymmetric wave propagation to purify signals and improve modeling of elastic wave-damage interactions remains a challenge. In this work, we propose exploiting asymmetric flexural wave propagation to enhance the accuracy and efficiency of WSHM. This phenomenon is realized in a self-adaptive metamaterial plate, for which two designs are developed. In the first, asymmetric wave propagation is achieved by applying different control parameters depending on the wave propagation direction. Secondly, gradient control parameters are introduced to break structural symmetry, thereby enabling asymmetric wave propagation. As an application, we propose a novel WSHM method for crack detection in plates based on the designed self-adaptive metamaterial. Compared with conventional approaches, the proposed method generates a more ordered wave field with minimal interference, leading to higher efficiency and accuracy. This work not only introduces two strategies for designing self-adaptive metamaterial plates that realize asymmetric wave propagation, but also opens new avenues for advancing metamaterial-based WSHM technologies.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":7109,"journal":{"name":"Acta Mechanica Sinica","volume":"42 12","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148927198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prescribed wrinkling pattern evolution in growing film-substrate biological systems by prestrain","authors":"Congshan Liu \u0000 (,&nbsp;),&nbsp;Wenxiang Tao \u0000 (,&nbsp;),&nbsp;Xinyu Wang \u0000 (,&nbsp;),&nbsp;Bin Wu \u0000 (,&nbsp;),&nbsp;Xiaoyi Chen \u0000 (,&nbsp;),&nbsp;Chaofeng Lü \u0000 (,&nbsp;)","doi":"10.1007/s10409-026-51265-x","DOIUrl":"10.1007/s10409-026-51265-x","url":null,"abstract":"<div><p>Wrinkling patterns across length scales are widely observed in film-substrate biological systems, and play an important role in maintaining essential bio-functions. Prestrain induced by heterogeneous growth is ubiquitous in living systems, especially in layered soft biological tissues. Here, we comprehensively investigate the influence of prestrain on the growth-induced wrinkling instability and post-buckling evolution of the film-substrate biological systems, through quantitative swelling experiments, theoretical analysis, and numerical simulations. Both experimental observation and theoretical analysis demonstrate that not only the wrinkling pattern but also the post-buckling amplitude can be prescribed by manipulating prestrain. The larger the prestrain value, the deeper the growth-induced wrinkles. Besides, the quantitative wrinkling experiments are in excellent agreement with our theoretical predictions across various conditions. The phase diagram for bifurcation type shows that the supercritical and subcritical bifurcations occur only depending on the normalized thickness and modulus. Both experimental and numerical results reveal that further growth/compression could trigger a secondary bifurcation of the emerging wrinkling patterns and lead to a period-doubling morphology in the film-substrate systems. This study not only deepens our understanding of the morphogenesis and evolution of some film-substrate biological tissues and organs, but also paves a promising way for the fabrication of morphology-related functional surfaces.\u0000</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":7109,"journal":{"name":"Acta Mechanica Sinica","volume":"42 11","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148926541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis and prediction of noise from installed subsonic chevron jets","authors":"Hasan Kamliya Jawahar,&nbsp;Benshuai Lyu \u0000 (,&nbsp;),&nbsp;Mahdi Azarpeyvand","doi":"10.1007/s10409-026-25995-x","DOIUrl":"10.1007/s10409-026-25995-x","url":null,"abstract":"<div><p>An experiment is conducted to investigate the effects of chevrons on installed subsonic jet noise at a Mach number of 0.5 using the NASA SMC000 (round) and SMC006 (chevron) nozzles. The jets are of a diameter <i>D</i> = 16.93 mm and are placed near a flat plate, with a horizontal separation distance <i>L</i> = 6.5D between the nozzle exit and the plate’s trailing edge. The vertical separation distance <i>H</i> varies between 1.5<i>D</i>, 2<i>D</i>, 2.5<i>D</i>, and 3<i>D</i>. Far-field sound is measured at various observable angles ranging from <i>θ</i> = 60° to 150° to the downstream jet axis on the reflected side. The measured noise spectra are compared to the predictions using the near-field scattering model developed by Lyu et al., together with the isolated near-field pressure spectra inputs from corresponding large eddy simulations for both nozzles. Results show that jet installation results in a strong noise amplification at low frequencies for both nozzles due to the scattering of the near-field pressure fluctuations and a mild noise increase at high frequencies due to surface reflection (reflected side). The low-frequency amplification is strongest at <i>H</i> = 1.5<i>D</i> and has a dipolar directivity. A secondary spectral hump appears within this low-frequency amplification hump, which is hypothesised due to the interference between the sound generated by the large coherent structures directly and that by their scattering at the trailing edge of the flat plate. The use of chevrons reduces the low-frequency noise for isolated jets, but leads to even stronger noise amplification for installed jets; this is likely due to enhanced jet mixing resulting in stronger near-field pressure fluctuations at a given radial distance. Results show that the scattering model can predict the low-frequency noise increase well at various observer angles for both nozzles, suggesting the validity of the instability-wave scattering mechanism and modelling for both round and chevron jets.\u0000</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":7109,"journal":{"name":"Acta Mechanica Sinica","volume":"42 12","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148926600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ground effect on rigid-elastic coupling flutter of flying-wing aircraft","authors":"Xusheng Mu \u0000 (,&nbsp;),&nbsp;Rui Huang \u0000 (,&nbsp;),&nbsp;Haojie Liu \u0000 (,&nbsp;),&nbsp;Qitong Zou \u0000 (,&nbsp;),&nbsp;Xinghua Zhou \u0000 (,&nbsp;),&nbsp;Haiyan Hu \u0000 (,&nbsp;)","doi":"10.1007/s10409-026-51162-x","DOIUrl":"10.1007/s10409-026-51162-x","url":null,"abstract":"<div><p>This paper presents a modeling approach for the rigid-elastic coupling flutter of flying-wing aircraft with ground effect taken into account. The paper begins with the formulation of a set of nonlinear coupled dynamic equations using Lagrange equations in terms of quasi-coordinates, with structural dynamics represented by the nodal coordinates of a finite element model and aerodynamic loads expressed through aerodynamic derivative matrices. These matrices are solvable from the unsteady vortex lattice method combined with the step response method, while the ground effect comes from mirror-image vortices. The linearization of the nonlinear dynamic equations enables the analysis of static aeroelastic trim and rigid-elastic coupling flutter for aircraft with ground effect. Numerical simulations of a flexible flying-wing aircraft indicate that the ground effect increases the frequency gap between the short-period mode and the first symmetric bending mode, thereby weakening rigid-elastic coupling and delaying the onset of flutter. From an energy-transfer perspective, ground effect reduces the net positive aerodynamic work associated with elastic bending, despite preserving the phase condition for aerodynamic excitation. Overall, the proposed method provides an effective framework for aeroelastic analysis of flexible aircraft operating near the ground and offers new insights into how ground effect modifies flutter characteristics.\u0000</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":7109,"journal":{"name":"Acta Mechanica Sinica","volume":"42 11","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148926542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Shear-driven transmission of infectious point source: implications for outdoor transmission risk","authors":"Zhilin Xia \u0000 (,&nbsp;),&nbsp;Yuan Ma \u0000 (,&nbsp;),&nbsp;Bofu Wang \u0000 (,&nbsp;),&nbsp;Quan Zhou \u0000 (,&nbsp;),&nbsp;Kai Leong Chong \u0000 (,&nbsp;)","doi":"10.1007/s10409-026-51042-x","DOIUrl":"10.1007/s10409-026-51042-x","url":null,"abstract":"<div><p>Understanding how ambient wind shear influences the transport of microdroplets is crucial for assessing airborne infection risks in realistic outdoor environments, where shear and turbulence are unavoidable yet often oversimplified. In this study, we perform direct numerical simulations of tiny particles transported in homogeneous shear turbulence across a range of shear Reynolds numbers (<i>Re</i>_<i>z</i>) from which we reveal pronounced anisotropic transmission characteristics. First, particle trajectories exhibit a transition from ballistic to diffusive behavior in the lateral directions, while streamwise transport remains ballistic due to mean shear advection. The probability density function of particle displacements exhibits a universal collapse when normalized by time-dependent mean and standard deviation, indicating robust statistical self-similarity. Detailed scaling analysis shows that the standard deviation along the lateral direction grows linearly before transitioning to <span>(sqrt t)</span> scaling. In contrast, along streamwise direction, the standard deviation of displacement follows <i>t</i>² scaling initially and transitions to a superdiffusive scaling <i>t</i>^3/2, consistently across all <i>Re</i>_<i>z</i>. The shear-induced enhancement of particle transmission can be understood by analyzing statistical moments. Based on these insights, we develop a simplified infection risk model using a well-mixed, joint-Gaussian assumption. The model captures essential features of anisotropic particle transmission under shear. It predicts that higher <i>Re</i>_<i>z</i> enhances downstream transport and accelerates dilution, it also shortens spread time, leading to a larger but less concentrated infectious zone. These findings highlight the critical role of wind shear in modulating airborne disease transmission and underscore the need to incorporate realistic flow conditions into public health risk assessments beyond classical uniform-wind assumptions.\u0000</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":7109,"journal":{"name":"Acta Mechanica Sinica","volume":"42 11","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148926540","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}