Coupling Method Research Articles

A three-dimensional meshless fluid–shell interaction framework based on smoothed particle hydrodynamics coupled with semi-meshless thin shell

Meshless methods are suitable for fluid–structure interaction simulations due to its Lagrangian feature and capability of handling large deformations. A three-dimensional meshless framework for the fluid–structure interaction simulation with shell structures is proposed in this study. The weakly compressible smoothed particle hydrodynamics is deployed in the fluid domain, where the boundary integral terms are incorporated to handle the one-layer shell boundary. On the other hand, a semi-meshless finite volume modeling method based on the Reissner–Mindlin shell is deployed in the one-layer shell domain. A one-way coupling method is employed for the interactive forcing between the fluid and shell particles near the interface, where the boundary integral method is employed to approximate the gradient and Laplacian operators in the fluid governing equations. Regarding the no-slip boundary, the original boundary integral method always leads to the artificial slipping phenomenon between the fluid and shell interface. To this end, a velocity penalty term with a relaxation factor is proposed to enforce the no-slip boundary condition, which substantially improves the accuracy of the original boundary integral method. In order to reduce computational costs, a multi-resolution strategy for the meshless framework is employed. A set of challenging cases with low and high Reynolds numbers are simulated by the present framework, and good accuracy is observed with the velocity penalty term in these cases. Overall, the new framework shows a satisfactory performance.

Hydrodynamic performance analysis of swimming processes in self-propelled manta rays

To fill the research gap regarding the whole process (steady-state and nonsteady-state phases) of median and/or paired fin (MPF) mode swimming in underwater organisms, a two-degree-of-freedom self-propelled coupling method of motion and hydrodynamics based on user-defined functions of Fluent software was established, and numerical simulations were carried out for the startup, acceleration, and steady-state phases of manta rays. The interaction mechanism among the hydrodynamic characteristics, vortex evolution, and pressure distribution was investigated in the mentioned phases. We concluded that the negative pressure zone generated by the leading edge vortex and the shear layer contributes to thrust generation and changes in swimming velocity dominate the hydrodynamic characteristics by affecting the evolution of the shear layer and the leading edge vortex, with a 17.54% increase in forward average velocity in the fourth cycle compared to the third cycle and a consequent 9.5% increase in average thrust. In the end, the relationship between the formation of trailing edge vortex rings and changes in thrust was revealed. The vortex ring contributes to the increase in thrust, but the formation of the vortex ring comes at the cost of the loss of the leading edge vortex negative pressure zone, which greatly affects thrust, decreasing to 38.3% of its peak. The swimming mechanism revealed in this study provides a reference for the study of MPF-driven biodynamics and a new simulation strategy for the prediction of bionic navigator motions.

Multi-fidelity simulation of aeroengine for far-off-design conditions using iterative coupled method based on auxiliary maps

Iterative coupled methods are widely used in multi-fidelity simulation of rotating components due to the simple implementation, which iteratively eliminates the errors between the computational fluid dynamics models and approximate characteristic maps. However, the convergence and accuracy of the iterative coupled method are trapped in characteristic maps. In particular, iterative steps increase sharply as the operation point moves away from the design point. To address these problems, this paper developed an auxiliary iterative coupled method that introduces the static-pressure-auxiliary characteristic maps and modification factor of mass flow into the component-level model. The developed auxiliary method realized the direct transfer of static pressure between the high-fidelity models and the component-level model. Multi-fidelity simulations of the throttle characteristics were carried out using both the auxiliary and traditional iterative coupled methods, and the simulation results were verified using the experimental data. Additionally, the consistency between the auxiliary and traditional iterative coupled methods was confirmed. Subsequently, multi-fidelity simulations of the speed and altitude characteristics were also conducted. The auxiliary and traditional iterative coupled methods were evaluated in terms of convergence speed and accuracy. The evaluation indicated that the auxiliary iterative coupled method significantly reduces iterative steps by approximately 50% at the near-choked state. In general, the auxiliary iterative coupled method is preferred as a development of the traditional iterative coupled method in the near-choked state, and the combined auxiliary-traditional iterative coupled method provides support for successful multi-fidelity simulation in far-off-design conditions.

Short-term Power Load Forecasting Based on EMD-GWO-BP

Abstract The short-range prediction of electricity demand holds immense importance in the strategic planning and advancement of the energy sector. However, the actual load sequence data reflects multiple complex properties, such as nonlinearity, non-stationarity, and temporal variation. In order to accurately forecast the load, this paper presents a three-level hybrid integrated short-term load prediction method composed of empirical mode decomposition (EMD), Grey Wolf Optimization (GWO) and BP neural network (BP). EMD is used to decompose load data to obtain good power consumption characteristics; GWO is used to obtain the optimal weight and threshold required for BP prediction. The hybrid integration method (EMD-GWO-BP) was evaluated using the 2017 annual data of Chaoyang County, Liaoning Province. The EMD-GWO-BP method was compared with the other two mainstream coupling methods (BP, GWO-BP). The statistical analysis Indicates that the suggested method within this document shows better forecast precision on three standard scales of MAPE, MAD and RMSE, which reflects the advanced nature of this method.

Multi-point impact behavior and the relationship between CAI strength and DBIP of PMI foam sandwich structures

Sandwich structures are vulnerable to multi-point impacts, and such impacts can result in a reduction in residual strength even catastrophic accident. Therefore, the multi-point impact behaviors of PMI foam sandwich structure are investigated and studied using experimental and numerical coupled methods. Three impact energy levels and five Distances Between Impact Positions (DBIP) are considered in details, and representative impact characteristics are compared to reveal the association between Compression After Impact (CAI) strength and DBIP. Results indicate that the interference between the multi-point impact events has a dominant effect on CAI strength when DBIP is small, and the variation in bending stiffness induced by the boundary effect is the dominant factor affecting CAI strength when DBIP ranges from 20 mm to 60 mm. In addition, matrix damage represents the primary damage mode in multi-point impact, and the calculated ratio of energy absorbed by the top face sheet and honeycomb core, in relation to the total absorbed energy, serves as a clear indicator of the damage severity experienced by both components. This work is enlightening for the structural design of impact-resistant composites.

Damage evolutions and failure mechanism of reinforced concrete impacted by abrasive water jet

Numerical simulations were conducted based on the smoothed particle hydrodynamics–finite element method coupling method to investigate the damage evolutions and failure mechanism of reinforced concrete impacted by abrasive water jet. The response processes of damage and fragmentation of reinforced concrete were analyzed. The influences of key jet parameters on fracture characteristics of reinforced concrete were obtained. In addition, evolution laws of stress and damage and the failure mechanism of reinforced concrete impacted by abrasive water jet were revealed. The results indicate that the morphologies of broken pits undergo changes in the following sequence: V-shape, U-shape, and hourglass-shape. The broken pit range almost linearly increases with the impact time. Increasing abrasive concentration is more conducive to peeling concrete above steel, but an appropriate concentration is more suitable for cutting steel. Increasing jet diameter can expand the broken pit width, especially its bottom width, and increase damage to concrete below steel. The concrete stresses beneath steel display a raindrop-like distribution pattern. The concrete protective layer mainly suffers from the multiple stepwise damage accumulation failure caused by compressive shear and tensile stresses, and the interface concrete between steel and protective layer undergoes brittle failure due to weak bonding strength and massive stress concentration. The concrete beneath steel mainly undergoes brittle failure due to strong extrusion effect of steel. In addition, the concrete within steel reinforcement framework is influenced by various forces, such as tensile stress and shear stress, leading to occurrence of damage accumulation without failure. The research results would lay the theoretical foundation for abrasive water jet efficiently crushing reinforced concrete.

Numerical investigation of various laser–waterjet coupling methods on spot power density distribution

This paper presents a numerical simulation study on the coupling of lasers and waterjets, focusing on the distribution of the spot power density. The analysis utilized a laser wavelength of 532 nm, chosen for its minimal energy attenuation in water. The key conditions for successful coupling were identified, including the necessity for the spot diameter of the laser beam to be smaller than the nozzle diameter of the waterjet fiber, the numerical aperture of the laser beam to be lower than that of the waterjet fiber, and the divergence angle of the laser to be smaller than the critical angle for total internal reflection. Using the ZEMAX simulation software, various coupling cases were explored, revealing that the radial displacement of the waterjet fiber relative to the laser axis has the most significant impact on the output power density, followed by angular deflection, whereas the axial displacement has the minimal effect. This study also investigates the combined effects of different influencing factors on the peak distribution of the output power density, uncovering distinct characteristics resulting from these deviations. Overall, the research findings provide theoretical insights for achieving effective coupling between fine waterjets and lasers as well as for the design of water-guided laser coupling devices.

FOREST FOOD RESOURCES IN THE SAKHA REPUBLIC (YAKUTIA)

According to the “Ecosystem Services of Russia” Prototype of National Report (2016), data on terrestrial ecosystem resources in Russia are fragmented. The purpose of this work is to fill the existing gaps in the knowledge of the biodiversity of plant species and the sustainability of traditional food systems across the economic zones of the Sakha Republic (Yakutia). Materials and methods. Although the range of edible plants in Yakutia counts more than 100 species, only nine species of berries, eight species of mushrooms, and three species of other food plants were classified as resource-significant based on the consolidated archive materials of the IBPC at FRC YaSC SB RAS and the results of the field studies carried out in 2002-2019. This list of twenty species was tested via a socio-economic survey undertaken as part of the RISE project in 2021-2023. The study was conducted with the permission of the local biomedical ethics committee of the Medical Institute of the North-Eastern Federal University. Each participant signed an informed consent form to be surveyed, according to the World Medical Association’s Declaration of Helsinki, which regulates the research involving human subjects. The study embraced 400 rural households. Results. The data on biological stocks of resource-significant food species of Yakutia’s forests were presented based on the consolidated archive materials and results of the field studies undertaken by the IBPC at FRC YaSC SB RAS. Coupled research methods of natural and social sciences were used to produce the estimates of the economic reserves of berries and mushrooms across economic zones of the Sakha Republic (Yakutia) and the volumes of their harvesting by rural households and the population of the region in general. Conclusion. Social methods have proven reliable for studying biodiversity in a large-sized region. They allow to fill the gaps in the databases built on the results of field studies, particularly in terms of popularity and, accordingly, the prevalence of certain food species. The higher productivity and diversity of flora in Southern Yakutia were confirmed compared to the Arctic and other economic zones. Funding. The reported study was performed under the e-Asia Climate Call and funded by RFBR, project number 21-55-70104, and project VI.52.1.8. “Theoretical and applied aspects of investigation the diversity of the vegetation of Northern and Central Yakutia (East Siberia)” 0376-2016-0001; registration number АААА-А17-117020110056-0.

A novel hybrid framework based on modified continued-fraction for pile-soil dynamic interaction of large-scale nuclear power structures

Accurate unbounded domain radiation damping and ground motion input in the near field are important for analyzing the dynamic safety of large-scale nuclear power structures (NPSs). The scaled boundary finite element method (SBFEM) can automatically satisfy the abovementioned radiation condition. However, owing to the coupling of time and space, conventional SBFEM is not competent to the analysis of large-scale structures. In this investigation, a novel coupled method is developed to improve the computational efficiency of unbounded domain dynamic stiffness using a modified continued-fraction technique. Furthermore, a set of systematic and efficient computational procedures for soil-structure interaction (SSI) are implemented based on parallel programming using a special preprocess. The proposed method is verified using three numerical examples, and another numerical application is analyzed for large-scale NPSs with a pile-raft foundation (PRF). The results show that the innovative method has wide engineering applicability with high numerical accuracy and stability, indicating that this method can be applied to the SSI dynamic seismic analysis of large-scale NPSs.

A Study on the Thermodynamic Response of Double-Armed Thin-Walled Piers under an FRP Anti-Collision Floating Pontoon Fire

Abstract: As a potential fire scenario for bridge structures, the safety impact of an FRP anti-collision floating pontoon fire on bridge structures cannot be ignored. Taking the FRP anti-collision floating pontoon fire that occurred in a continuous rigid-frame bridge as the engineering background, the damage condition of the actual bridge fire scene was first investigated. In addition, FDS 5.3 software was used to simulate the FRP anti-collision floating pontoon fire scenario. Furthermore, the thermal–structural coupling method was used to investigate the thermodynamic response of double-armed thin-walled piers under fire. The results show that the FRP anti-collision floating pontoon fire causes localized concrete carbonization and spalling on the surface of the P2 pier, and the FRP anti-collision floating pontoons are largely destroyed. The fire has the greatest impact on the P2-1 pier, with the highest temperature of 667 °C on the windward side and the highest temperature of 326 °C on the leeward side. The temperature impact range is 6 m above the bearing platform, and the maximum damage depth of pier body concrete is 84.58 mm. The deformation and stress of the P2 pier under fire do not show significant changes and do not exceed the allowable limits for structural deformation and material stress. Therefore, the impact of this fire accident on the structural safety of the continuous rigid-frame bridge is minor. This study's results provide reliable guidance for the fire safety assessment and post-fire structural repair of the continuous rigid-frame bridge.

A multi-scale and multi-physical coupling method for the transient characteristics of space nuclear reactor

In the future of deep space exploration, space nuclear reactors (SNRs) are essential because they can provide a robust, sustainable energy supply independent of the environment. SNRs have complex multi-physics coupling effects, and their systems involve many modules. The traditional method uses the lumped parameter model, or single-filed, which cannot accurately describe the transient characteristics and has low spatial resolution and poor data representation. Thus, developing a multi-dimensional, multi-physics coupled method to analyze and design SNRs is necessary. This work proposes a multi-dimensional, multi-physics coupled method for the SNRs. A transient coupling code for the space thermionic reactor TOPAZ-II based on OpenFOAM was developed. The reactor neutron physics model, multi-region heat transfer model, thermoelectric conversion model, electromagnetic pump model, and heat pipe radiator model are included. Different scale models are imported by the code, including a three-dimensional reactor model and a two-dimensional heat pipe. Furthermore, the experimental data from the V-71 test unit were used to verify the developed code. The shutdown and startup of the improved TOPAZ-II system are simulated using the developed code. The results show that the calculated results agree well with the experimental data. During the startup and shutdown processes, the material temperatures remained within acceptable limits, so it can be considered that the developed 2D/3D system analysis for SNRs has successfully achieved a high-dimensional simulation of transient characteristics, accurately capturing the spatial distribution of SNRs at different scales.

Analysis of damage mechanisms and controlling factors of fine particle migration in unconsolidated sandstone reservoirs based on reservoir classification

AbstractParticle migration in oil and gas reservoirs is a common phenomenon in the process of oil and gas development, and is considered to be an important reason for the damage of reservoir permeability and the reduction of oil and gas productivity. The mechanism of this phenomenon includes the desorption, migration, and precipitation of particles, which eventually clogs the throat and causes reservoir damage. Therefore, it is necessary to accurately characterize the complex mechanism of particle migration and identify the main controlling factors of particle migration, which is very important for efficient oilfield development and plugging solution. First, the reservoir types are divided into three types and the pore structure models of different types of reservoirs are established. Then, computational fluid dynamics and discrete element coupling method numerical simulation and microscopic visualization of pore throat structure model were combined, to characterize the rules of particles and migration, and analyze the main controlling factors. Finally, a typical model of particle migration and clogging is established. The results show that particle size/throat and particle concentration are the key factors affecting particle plugging, and particle migration has the least effect on the permeability of Type I reservoir and the greatest damage to Type III reservoir. According to the mechanical and hydrodynamic behavior of particles in porous media, three mechanisms and six modes of particle plugging are proposed.

Thermodynamic and economic analysis of the combined cooling, heating, and power system coupled with the constant-pressure compressed air energy storage

Combined cooling, heating, and power (CCHP) technology represents a widely adopted and promising approach for achieving high energy efficiency. However, the conventional operational mode of electricity determined by heating often leads to poor partial load efficiency, strong heat-electricity coupling, and inflexible regulation in the gas turbine system. This paper proposes a novel CCHP system coupling the gas turbine and constant-pressure compressed air energy storage. Thermodynamic and economic models are built to evaluate the four schemes of the coupled system based on the simple cycle or regenerative cycle gas turbine with a 10 MW power output, respectively. The results show that different coupling methods offer advantages in various aspects. The coupled scheme employing the simple cycle gas turbine and the ejector demonstrates the highest primary energy ratio of 68.94 %. Meanwhile, the coupled scheme using the regenerative cycle gas turbine and expander exhibits superior economic performance, with the fuel cost output rate and system profit reaching 1.426 and $734.43, respectively. Integrating constant-pressure compressed air energy storage effectively widens the heat-electricity ratio adjustment range of the gas turbine CCHP system. Among them, the coupled scheme employing the regenerative cycle gas turbine and ejector achieves the highest relative variation rate of the heat-electricity ratio, reaching 13.68 %.

Joint inversion of ERT and ambient noise surface wave data with DPC-guided fuzzy c-means clustering for near-surface imaging

SUMMARY We present a novel strategy for performing joint inversion with guided fuzzy c-means (GFCM) clustering coupling and apply it to electrical resistivity tomography (ERT) and ambient noise surface wave (ANSW) data. To accurately extract a priori clustering information, we use density peak clustering (DPC) rather than fuzzy c-means (FCM). The number and centres of resistivity and shear-wave velocity a priori clusters are extracted by DPC and then used to guide the joint inversion with the GFCM clustering coupling of ERT and ANSW data. Synthetic and field data are used to evaluate the flow and algorithm of DPC-GFCM clustering joint inversion. The results of synthetic examples show that the models recovered by the DPC-GFCM clustering joint inversion are nearly the same as the true models and are more accurate than those inverted using individual inversion and FCM-GFCM clustering joint inversion. In the field case, the depths of the stratigraphic interfaces shown in the resistivity and shear-wave velocity models inverted by DPC-GFCM clustering joint inversion are nearly consistent with those from the drilling data. In contrast, the strata recovered by the individual inversion and FCM-GFCM clustering joint inversion significantly differ from the drilling results. Both the synthetic and field examples verify the effectiveness of the DPC-GFCM clustering coupling method used for the joint inversion of ERT and ANSW data acquired from the near surface with strong heterogeneity. This novel approach can also be applied to other types of geophysical data.

The hyperbolic sine chaotification model and its applications

Some existing chaotic systems suffer from issues such as period windows, discontinuous parameter ranges, and dynamical degradation, which seriously limit their application. Therefore, designing high-performance anti-degradation chaotic systems is of great significance. In this paper, a novel hyperbolic sine chaotification model (HSCM) is proposed. It allows for the use of any chaotic maps or linear functions as the seed maps, and employs a closed-loop modulation coupling (CMC) method to extend it to high-dimensional (HD) chaotic maps. Theoretical and experimental results show that this model can effectively improve the Lyapunov exponent (LE) of the seed chaotic map and expand the parameter ranges. In addition, it can also resist the dynamical degradation under finite computational precision. Based on the HSCM, a novel eight-dimensional (8D) HSCM is designed, and implemented through field-programmable gate array (FPGA) in both serial and parallel modes, respectively. Furthermore, the novel chaotic maps are applied to pseudo-random sequence generator (PRNG) and image compression under finite computing precision. Experimental results indicate that the novel chaotification model has greatly broad application prospects.

Analysis of Stray Current Leakage in Subway Traction Power Supply System Based on Field-Circuit Coupling

In a rail transit system, there is a constant leakage of current from the subway rails to the earth, and these stray currents have complex propagation paths and a wide range of influence. Since no stray current collection devices are installed at subway depots, some of the stray current leaking from the mainline will converge at the depot, seriously corroding the structural reinforcement and buried metal of the station, thereby jeopardizing the normal operation of subway trains and passenger safety. In this paper, a field-circuit coupling method is proposed to analyze the current leakage and distribution law of the subway mainline and depot. It is found that the failure of the gauge block at the mainline will trigger the maximum leakage of rail current. Additionally, it is observed that the stray current distribution at the depot is mainly influenced by the operating status of the one-way conduction device (OWCD) and the change of rail potential. These results validate the applicability and effectiveness of the field-circuit coupling method proposed in this paper and provide new technical support for the study of stray current leakage distribution in subways.

Two-dimensional diffraction and radiation problems of a floating body in varying bathymetry

In this study, a coupling method of the higher order boundary element method and the eigenfunction expansion method is applied to investigate the diffraction and radiation problems of a floating body over an uneven seabed under the assumption of linear small-amplitude wave theory. The wave exciting forces and hydrodynamic coefficients are calculated for a floating rectangular box. It is found that the curves of the wave exciting forces and hydrodynamic coefficients versus frequency become fluctuating as the horizontal length L and vertical height D of the sloping seabed gradually increase. The period of the fluctuations decreases with the increase of L, and the magnitude of the fluctuations increases with the increase of D. The mechanism of the fluctuation phenomenon is then examined, and found that it is associated with the wave reflection from the slope seabed. With increasing horizontal scale L and vertical scale D of the sloping seabed, the amplitude and phase of the reflection wave change, which leads to the combined action of the incident, scattering and reflection waves fluctuating with the wave frequency.

An Ultramicroelectrode Electrochemistry and Surface Plasmon Resonance Coupling Method for Cell Exocytosis Study.

Exocytosis of a single cell has been extensively researched in recent years due to its close association with numerous diseases. However, current methods only investigate exocytosis at either the single-cell or multiple-cell level, and a method for simultaneously studying exocytosis at both levels has yet to be established. In this study, a combined device incorporating ultramicroelectrode (UME) electrochemistry and surface plasmon resonance (SPR) was developed, enabling the simultaneous monitoring of single-cell and multiple-cell exocytosis. PC12 cells were cultured directly on the SPR sensing Au film, with a carboxylated carbon nanopipette (c-CNP) electrode employed for electrochemical detection in the SPR reaction cell. Upon exocytosis, the released dopamine diffuses onto the inner wall of c-CNP, undergoing an electrochemical reaction to generate a current peak. Concurrently, exocytosis can also induce changes in the refractive index of the Au film surface, leading to the SPR signal. Consequently, the device enables real-time monitoring of exocytosis from both single and multiple cells with a high spatiotemporal resolution. The c-CNP electrode exhibited excellent resistance to protein contamination, high sensitivity for dopamine detection, and the capability to continuously monitor dopamine exocytosis over an extended period. Analysis of both SPR and electrochemical signals revealed a positive correlation between changes in the SPR signal and the frequency of exocytosis. This study introduces a novel method and platform for the simultaneous investigation of single-cell and multiple-cell exocytosis.

Spatial correlation between electricity generation and economic scale in Africa.

This study attempts to determine whether there is a spatial correlation between electricity generation and economic scale promoting coordinated development in Africa. We explore the spatial similarity and gray correlation degree between electricity generation and economic scale in Africa since the 21st century by adopting barycenter coupling and Gray Correlation Analysis method. We argue that there is a strong correlation between electricity generation and economic scale. Our findings indicate a significant spatial difference in electricity generation, mainly concentrated in Northern and Southern Africa. Furthermore, spatial pattern remains largely consistent over time, mirroring trends observed at the economic scale. Electricity generation and economic scale were concentrated in six countries- South Africa, Egypt, Algeria, Nigeria, Morocco, and Libya- and did not change significantly over time. A correlation analysis between electricity generation and the economic scale further confirmed this, with a linear coefficient of 0.907. Both the gravity centers of economic scale and electricity generation in Africa move farther in the north-south direction than in the East-West direction, with the former showing a Southwest-Northeast-Southwest track feature and the latter a Northeast-Southwest track feature. The spatial distribution of the gravity centers of electricity generation and the gravity centers of the economic scale in Africa are highly consistent; electricity generation highly correlates with the economic scale, consistent with the research conclusion obtained by the Gray Correlation Analysis method. This study suggests the coordinated development of electricity generation and economic scales in various African countries.

Bowtie Nanoantenna LSPR Biosensor for Early Prediction of Preeclampsia.

The concentration of the placental circulating factor in early pregnancy is often extremely low, and the traditional prediction method cannot meet the clinical demand for early detection preeclampsia in high-risk gravida. It is of prime importance to seek an ultra-sensitive early prediction method. In this study, finite-different time-domain (FDTD) and Discrete Dipole Approximation (DDA) simulation, and electron beam lithography (EBL) methods were used to develop a bowtie nanoantenna (BNA) with the best field enhancement and maximum coupling efficiency. Bio-modification of the placental circulating factor (sFlt-1, PLGF) to the noble nanoparticles based on the amino coupling method were explored. A BNA LSPR biosensor which can specifically identify the placental circulating factor in preeclampsia was constructed. The BNA LSPR biosensor can detect serum placental circulating factors without toxic labeling. Serum sFlt-1 extinction signal (Δλmax) in the preeclampsia group was higher than that in the normal pregnancy group (14.37 ± 2.56 nm vs. 4.21 ± 1.36 nm), p = 0.008, while the serum PLGF extinction signal in the preeclampsia group was lower than that in the normal pregnancy group (5.36 ± 3.15 nm vs. 11.47 ± 4.92 nm), p = 0.013. The LSPR biosensor detection results were linearly consistent with the ELISA kit. LSPR biosensor based on BNA can identify the serum placental circulating factor of preeclampsia with high sensitivity, without toxic labeling and with simple operation, and it is expected to be an early detection method for preeclampsia.