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Neural boundary shape functions in physics-informed neural networks for discontinuous and high-frequency problems 认领 引用
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作者 P.T.NGUYEN K.A.LUONG J.H.LEE 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2026年第2期423-442,共20页
Physics-informed neural networks(PINNs)have been shown as powerful tools for solving partial differential equations(PDEs)by embedding physical laws into the network training.Despite their remarkable results,complicate... Physics-informed neural networks(PINNs)have been shown as powerful tools for solving partial differential equations(PDEs)by embedding physical laws into the network training.Despite their remarkable results,complicated problems such as irregular boundary conditions(BCs)and discontinuous or high-frequency behaviors remain persistent challenges for PINNs.For these reasons,we propose a novel two-phase framework,where a neural network is first trained to represent shape functions that can capture the irregularity of BCs in the first phase,and then these neural network-based shape functions are used to construct boundary shape functions(BSFs)that exactly satisfy both essential and natural BCs in PINNs in the second phase.This scheme is integrated into both the strong-form and energy PINN approaches,thereby improving the quality of solution prediction in the cases of irregular BCs.In addition,this study examines the benefits and limitations of these approaches in handling discontinuous and high-frequency problems.Overall,our method offers a unified and flexible solution framework that addresses key limitations of existing PINN methods with higher accuracy and stability for general PDE problems in solid mechanics. 展开更多
关键词 physics-informed neural network(PINN) boundary shape function(BSF) strong-form approach energy approach discontinuity high-frequency problem
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Solving the Optimal Control Problems of Nonlinear Duffing Oscillators By Using an Iterative Shape Functions Method 认领 引用 被引量：2
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作者 Cheinshan Liu Chunglun Kuo Jiangren Chang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第1期33-48,共16页
In the optimal control problem of nonlinear dynamical system,the Hamiltonian formulation is useful and powerful to solve an optimal control force.However,the resulting Euler-Lagrange equations are not easy to solve,wh... In the optimal control problem of nonlinear dynamical system,the Hamiltonian formulation is useful and powerful to solve an optimal control force.However,the resulting Euler-Lagrange equations are not easy to solve,when the performance index is complicated,because one may encounter a two-point boundary value problem of nonlinear differential algebraic equations.To be a numerical method,it is hard to exactly preserve all the specified conditions,which might deteriorate the accuracy of numerical solution.With this in mind,we develop a novel algorithm to find the solution of the optimal control problem of nonlinear Duffing oscillator,which can exactly satisfy all the required conditions for the minimality of the performance index.A new idea of shape functions method(SFM)is introduced,from which we can transform the optimal control problems to the initial value problems for the new variables,whose initial values are given arbitrarily,and meanwhile the terminal values are determined iteratively.Numerical examples confirm the high-performance of the iterative algorithms based on the SFM,which are convergence fast,and also provide very accurate solutions.The new algorithm is robust,even large noise is imposed on the input data. 展开更多
关键词 Nonlinear Duffing oscillator optimal control problem Hamiltonian formulation shape functions method iterative algorithm
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The choosing of reproducing kernel particle shape function with mathematic proof 认领 引用
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作者 夏茂辉 李金 《Chinese Physics B》 CAS 2007年第10期3067-3071,共5页
Many mechanical problems can be induced from differential equations with boundary conditions; there exist analytic and numerical methods for solving the differential equations. Usually it is not so easy to obtain anal... Many mechanical problems can be induced from differential equations with boundary conditions; there exist analytic and numerical methods for solving the differential equations. Usually it is not so easy to obtain analytic solutions. So it is necessary to give numerical solutions. The reproducing kernel particle （RKP） method is based on the Carlerkin Meshless method. According to the Sobolev space and Fourier transform, the RKP shape function is mathematically proved in this paper. 展开更多
关键词 point of interpolation particle reproducing kernel particle shape function
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Modeling unbalanced rotor system with continuous viscoelastic shaft by frequency-dependent shape function 认领 引用 被引量：1
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作者 WANG Shu-han GUO Wei +2 位作者 XU Xiang-yang LIU Yan-fang LI Wen-yong 《Journal of Central South University》 SCIE EI CAS 2013年第12期3421-3430,共10页
A reduced-order dynamic model for an unbalanced rotor system is developed,taking the coupling between torsional and lateral vibrations into account.It is assumed that a shaft is regarded as a continuous viscoelastic s... A reduced-order dynamic model for an unbalanced rotor system is developed,taking the coupling between torsional and lateral vibrations into account.It is assumed that a shaft is regarded as a continuous viscoelastic shaft with unbalanced and small deformation properties.The equations of motion for the torsional and lateral vibrations are derived using Lagrange's approach with the frequency-dependent shape function.The rotor torsional vibration is coupled with the lateral vibrations by unbalance elements in a way of excitations.Simulation and experiment results show clearly that the torsional vibration has strong impact on the rotor lateral vibrations,and it causes subharmonic and superharmonic excitations through unbalance elements,which leads to the superharmonic resonances in the lateral vibrations.This model with low-order and high accuracy is suitable for rotor dynamic analysis in real time simulation as well as for active vibration control syntheses. 展开更多
关键词 rotor dynamics distributed unbalance rotor shape function torsional and lateral vibrations coupling
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ON THE SELECTION OF SHAPE FUNCTION SPACES OF TRIANGULAR PLATE ELEMENTS 认领 引用
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作者 陈绍春 《Acta Mathematica Scientia》 SCIE 1995年第3期275-282,共8页
Using the method of undetermined coefficients, we construct a set of shape function spaces of nine-node triangular plate elements converging for any meshes, which generalize Spect's element and Veubeke's element.
关键词 unconforming finite element shape function space method of undetermined coefficients
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A Solver for Helmholtz System Generated by the Discretization of Wave Shape Functions 认领 引用 被引量：1
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作者 Long Yuan Qiya Hu 《Advances in Applied Mathematics and Mechanics》 SCIE 2013年第6期791-808,共18页
An interesting discretization method for Helmholtz equations was introduced in B.Despres[1].This method is based on the ultra weak variational formulation(UWVF)and the wave shape functions,which are exact solutions of... An interesting discretization method for Helmholtz equations was introduced in B.Despres[1].This method is based on the ultra weak variational formulation(UWVF)and the wave shape functions,which are exact solutions of the governing Helmholtz equation.In this paper we are concerned with fast solver for the system generated by the method in[1].We propose a new preconditioner for such system,which can be viewed as a combination between a coarse solver and the block diagonal preconditioner introduced in[13].In our numerical experiments,this preconditioner is applied to solve both two-dimensional and three-dimensional Helmholtz equations,and the numerical results illustrate that the new preconditioner is much more efficient than the original block diagonal preconditioner. 展开更多
关键词 Helmholtz equation ultra weak variational formulation wave shape functions preconditioner iteration counts
Design and additive manufacturing of bionic hybrid structure inspired by cuttlebone to achieve superior mechanical properties and shape memory function 认领 引用 被引量：9
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作者 Luhao Yuan Dongdong Gu +8 位作者 Xin Liu Keyu Shi Kaijie Lin He Liu Han Zhang Donghua Dai Jianfeng Sun Wenxin Chen Jie Wang 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第5期189-206,共18页
Lightweight porous materials with high load-bearing,damage tolerance and energy absorption(EA)as well as intelligence of shape recovery after material deformation are beneficial and critical for many applications,e.g.... Lightweight porous materials with high load-bearing,damage tolerance and energy absorption(EA)as well as intelligence of shape recovery after material deformation are beneficial and critical for many applications,e.g.aerospace,automobiles,electronics,etc.Cuttlebone produced in the cuttlefish has evolved vertical walls with the optimal corrugation gradient,enabling stress homogenization,significant load bearing,and damage tolerance to protect the organism from high external pressures in the deep sea.This work illustrated that the complex hybrid wave shape in cuttlebone walls,becoming more tortuous from bottom to top,creates a lightweight,load-bearing structure with progressive failure.By mimicking the cuttlebone,a novel bionic hybrid structure(BHS)was proposed,and as a comparison,a regular corrugated structure and a straight wall structure were designed.Three types of designed structures have been successfully manufactured by laser powder bed fusion(LPBF)with NiTi powder.The LPBF-processed BHS exhibited a total porosity of 0.042% and a good dimensional accuracy with a peak deviation of 17.4μm.Microstructural analysis indicated that the LPBF-processed BHS had a strong(001)crystallographic orientation and an average size of 9.85μm.Mechanical analysis revealed the LPBF-processed BHS could withstand over 25000 times its weight without significant deformation and had the highest specific EA value(5.32 J·g−1)due to the absence of stress concentration and progressive wall failure during compression.Cyclic compression testing showed that LPBF-processed BHS possessed superior viscoelastic and elasticity energy dissipation capacity.Importantly,the uniform reversible phase transition from martensite to austenite in the walls enables the structure to largely recover its pre-deformation shape when heated(over 99% recovery rate).These design strategies can serve as valuable references for the development of intelligent components that possess high mechanical efficiency and shape memory capabilities. 展开更多
关键词 additive manufacturing laser powder bed fusion bionic structure cuttlebone mechanical properties shape memory function
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Shape control on probability density function in stochastic systems 认领 引用 被引量：5
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作者 Lingzhi Wang Fucai Qian Jun Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第1期144-149,共6页
A novel strategy of probability density function （PDF） shape control is proposed in stochastic systems. The control er is designed whose parameters are optimal y obtained through the improved particle swarm optimiza... A novel strategy of probability density function （PDF） shape control is proposed in stochastic systems. The control er is designed whose parameters are optimal y obtained through the improved particle swarm optimization algorithm. The parameters of the control er are viewed as the space position of a particle in particle swarm optimization algorithm and updated continual y until the control er makes the PDF of the state variable as close as possible to the expected PDF. The proposed PDF shape control technique is compared with the equivalent linearization technique through simulation experiments. The results show the superiority and the effectiveness of the proposed method. The control er is excellent in making the state PDF fol ow the expected PDF and has the very smal error between the state PDF and the expected PDF, solving the control problem of the PDF shape in stochastic systems effectively. 展开更多
关键词 stochastic systems probability density function （PDF）,shape control improved particle swarm optimization.
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Changes of Left Ventricular Geometry Shape and Left Ventricular Regional Function in Patients With Dilated Cardiomyopathy 认领 引用 被引量：1
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作者 王良玉 谢明星 +3 位作者 李庆波 陈平 蔡志雄 朱稚丹 《South China Journal of Cardiology》 CAS 2009年第1期9-14,共6页
To assess the left ventricle regional systolic and diastolic function, left ventricle geometry and left venticle sphericity indexes in patients with dilated cardiomyopathy （DCM） by quantitative tissue velocity imagi... To assess the left ventricle regional systolic and diastolic function, left ventricle geometry and left venticle sphericity indexes in patients with dilated cardiomyopathy （DCM） by quantitative tissue velocity imaging （QTVI）. Methods Thirty normal subjects and 52 DCM patients underwent QTVI and colour Doppler flow imaging study in order to measure the left ventricular regional function along left ventricle apical long-axis view and the left ventricle geometry. Peak tissue velocities of left venticle regional muscular tissue during systole （ Vs）, systolic acceleration （ a）, early diastole（Ve） and left atrium contraction（Va） along left venticle apical long axis view were measured. The indexes of left ventricular regional systolic and diastolic function were mearsured at the same time. The left ventricle geometry shape was reflected from the systolic and diastolic sphericity index （Sis and Sid）, the left ventricular ejection fraction （LVEF） and D wave / A wave （PVd/PVa） of pulmonary veins flowing spectrum reflected the global left ventricular systolic and diastolic function. The Vs, Ve, Va, a, PVd/PVa ratio, LVEF, Sis, Sid and their correlations between normal subjects and patients with DCM were compared and analyzed. Results Vs, Ve, Va, a, PVd/PVa, Sis and Sid in patients with DCM were lower than those in normal persons. There were significant relations between Sis and a （ r = 0. 6142, P 〈 0. 05）, Ve/Va and Sid （ r = 0. 6271, P 〈 0. 05 ）. Conclusions QTVI offer a newer method which has a higher sensitivity and accuracy in evaluating the left venticle regional systolic and diastolic function in DCM patients. There was significant relation between regional cardiac function and left venticle sphericity. （ S Chin J Cardiol 2009; 10（1） ： 9 -14） 展开更多
关键词 quantitative tissue velocity imaging geometry shape dilated cardiomyopathy left ventricular function
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TORSIONAL IMPACT RESPONSE OF A PENNY-SHAPED CRACK IN A FUNCTIONAL GRADED STRIP 认领 引用
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作者 冯文杰 李向国 王守东 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第12期1398-1404,共7页
The torsional impact response of a penny-shaped crack in a nonhomogeneous strip is considered. The shear modulus is assumed to be functionally graded such that the mathematics is tractable. Laplace and Hankel transfor... The torsional impact response of a penny-shaped crack in a nonhomogeneous strip is considered. The shear modulus is assumed to be functionally graded such that the mathematics is tractable. Laplace and Hankel transforms were used to reduce the problem to solving a Fredholm integral equation. The crack tip stress field is obtained by considering the asymptotic behavior of Bessel function. Explicit expressions of both the dynamic stress intensity factor and the energy density factor were derived.And it is shown that, as crack driving force, they are equivalent for the present crack problem. Investigated are the effects of material nonhomogeneity and (strip's) highness on the dynamic fracture behavior. Numerical results reveal that the peak of the dynamic stress intensity factor can be suppressed by increasing the nonhomogeneity parameter of the shear modulus, and that the dynamic behavior varies little with the adjusting of the strip's highness. 展开更多
关键词 dynamic stress intensity factor torsional impact penny-shaped crack functionally graded strip integral transform energy density factor
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Influence of Inclusion Shape on Thermoelasto-Plastic Optimun Design of Ceramic Metal Functionally Graded Materials 认领 引用
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作者 王继辉 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2001年第1期19-24,29,共6页
A nonlinear finite element method is applied to observe how inclusion shape influence the thermal response of a ceramic-metal functionally graded material (FGM). The elastic and plastic behaviors of the layers which a... A nonlinear finite element method is applied to observe how inclusion shape influence the thermal response of a ceramic-metal functionally graded material (FGM). The elastic and plastic behaviors of the layers which are two-phase isotropic composites consisting of randomly oriented elastic spheroidal Inclusions and a ductile matrix are predicted by cc mean field method. The prediction results show that inclusion shape has remarkable influence on the overall behavior of the composite. The consequences of the thermal response analysis of the FGM are that the response is dependent on inclusion shape and its composition profile cooperatively and that the plastic behavior of each layer should be taken into account in optimum design of a ceramic-metal FGM. 展开更多
关键词 inclusion shape ceramic-metal functionally graded material mean field method elastoplastic behavior
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ON SHAPE PRESERVING EXTENSION AND APPROXIMATION OF FUNCTIONS 认领 引用
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作者 卢旭光 《Analysis in Theory and Applications》 1992年第2期67-88,共22页
We establish the concept of shapes of functions by using partial differential inequalites. Our definition about shapes includes some usual shapes such as convex,subharmonic,etc.,and gives many new shapes of functions.... We establish the concept of shapes of functions by using partial differential inequalites. Our definition about shapes includes some usual shapes such as convex,subharmonic,etc.,and gives many new shapes of functions.The main results show that the shape preserving approxi- mation has close relation to the shape preserving extension.One of our main results shows that if f∈C(Ω)has some shape defined by our definition,then f can be uniformly approximated by polynomials P_n ∈p_n(n∈N)which have the same shape in Ω,and the degree of the ap- proximation is Cω(f,n-β)with constants C,β>0. 展开更多
关键词 ON SHAPE PRESERVING EXTENSION AND APPROXIMATION OF FUNCTIONS
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Improved shape hardening function for bounding surface model for cohesive soils 认领 引用 被引量：1
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作者 Andrés Nieto-Leal Victor N.Kaliakin 《Journal of Rock Mechanics and Geotechnical Engineering》 CSCD 2014年第4期328-337,共10页
A shape hardening function is developed that improves the predictive capabilities of the generalized bounding surface model for cohesive soils,especially when applied to overconsolidated specimens.This improvement is ... A shape hardening function is developed that improves the predictive capabilities of the generalized bounding surface model for cohesive soils,especially when applied to overconsolidated specimens.This improvement is realized without any changes to the simple elliptical shape of the bounding surface,and actually reduces the number of parameters associated with the model by one. 展开更多
关键词 Constitutive model Bounding surface plasticity Shape hardening function Clay
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Advances in the Element-Free Galerkin Method:From Linear Solid Mechanics to Multi-Physics Applications and Hybrid Domain Coupling 认领 引用
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作者 Álvarez-Hostos Juan C Zambrano-Carrillo Javier A Sarache-Piña Alirio J 《Computer Modeling in Engineering & Sciences》 SCIE EI 2026年第4期62-137,共76页
The Element-Free Galerkin(EFG)method was originally developed for linear solid mechanics problems,using Moving Least Squares(MLS)approximations to construct shape functions for the numerical approximation of the displ... The Element-Free Galerkin(EFG)method was originally developed for linear solid mechanics problems,using Moving Least Squares(MLS)approximations to construct shape functions for the numerical approximation of the displacement field and its variations within the weak form of the equilibrium equations.Over the past decades,it has evolved into a versatile meshfree framework applicable to a broad spectrum of engineering and scientific problems.This review provides a comprehensive account of the main advances in EFG,tracing its development from the original formulation and early challenges to the strategies devised to overcome them.Subsequent improvements in accuracy,stability,and computational efficiency are examined in detail,together with alternative shape function constructions such as Moving Kriging(MK)and Local Maximum Entropy(LME)approximations.The extension of EFG to multiphysics problems is discussed,emphasizing how analogies with the Finite Element Method(FEM)have enabled the adaptation of established stabilization and enrichment techniques.Hybrid FEM-EFG coupling strategies are also reviewed.The article concludes with a survey of significant applications in mechanics and transport phenomena,highlighting their broader implications in science and technology. 展开更多
关键词 Element-free galerkin shape functions applications multiphysics FEM-EFG coupling meshfree methods
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基于u-p-U耦合形式的全隐式物质点法及水土耦合大变形分析 认领 引用 被引量：1
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作者 郑响凑 王树英 +1 位作者 阳军生 杨峰 《东南大学学报（自然科学版）》 EI CAS CSCD 北大核心 2026年第1期125-133,共9页
基于物质点法的水土耦合大变形模拟逐渐成为计算岩土领域的研究热点,然而现有水土耦合物质点法研究多采用条件稳定的显式积分方法,需采用极小的时间步长,计算效率低下。鉴于此,在采用完全动态控制方程u-p-U格式的前提下,推导了在广义插... 基于物质点法的水土耦合大变形模拟逐渐成为计算岩土领域的研究热点,然而现有水土耦合物质点法研究多采用条件稳定的显式积分方法,需采用极小的时间步长,计算效率低下。鉴于此,在采用完全动态控制方程u-p-U格式的前提下,推导了在广义插值形函数(GIMP)框架下水土耦合控制方程的完全隐式积分形式,给出采用u-p-U格式的全隐式耦合物质点法求解流程及编程实现方法,达到稳定求解且提高求解效率的目的。通过2个典型算例验证本文提出的在完全动态控制方程下的全隐式耦合物质点法的可靠性和准确性。最后,结合饱和边坡大变形失稳破坏过程模拟,进一步验证该方法的适用性。计算结果表明,基于u-p-U动态耦合形式的全隐式物质点法能有效揭示水土耦合大变形过程中的水土耦合作用机理。 展开更多
关键词 物质点法 全隐式积分 水土耦合 广义插值形函数 完全动态控制方程
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Pull-in instability analyses for NEMS actuators with quartic shape approximation 认领 引用 被引量：4
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作者 Junsheng DUAN Zongxue LI Jinyuan LIU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2016年第3期303-314,共12页
The pull-in instability of a cantilever nano-actuator model incorporating the effects of the surface, the fringing field, and the Casimir attraction force is investigated. A new quartic polynomial is proposed as the s... The pull-in instability of a cantilever nano-actuator model incorporating the effects of the surface, the fringing field, and the Casimir attraction force is investigated. A new quartic polynomial is proposed as the shape function of the beam during the deflection, satisfying all of the four boundary values. The Gaussian quadrature rule is used to treat the involved integrations, and the design parameters are preserved in the evaluated formulas. The analytic expressions are derived for the tip deflection and pull-in parameters of the cantilever beam. The micro-electromechanical system （MEMS） cantilever actuators and freestanding nano-actuators are considered as two special cases. It is proved that the proposed method is convenient for the analyses of the effects of the surface, the Casimir force, and the fringing field on the pull-in parameters. 展开更多
关键词 micro-electromechanical system （MEMS） nano-electromechanical system（NEMS） Casimir force pull-in instability quartic shape function
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PENALTY FUNCTION METHOD OF CONTINUUM SHAPE OPTIMIZAION 认领 引用 被引量：2
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作者 Guo Taiyong Wang Xinrong Liang Yingchun 《Chinese Journal of Mechanical Engineering》 CAS 1994年第1期58-62,共5页
The penalty function method of continuum shape optimization and its sensitivity analysis technique are presented. A relatively simple integrated shape optimization system is developed and used to optimize the design o... The penalty function method of continuum shape optimization and its sensitivity analysis technique are presented. A relatively simple integrated shape optimization system is developed and used to optimize the design of the inner frame shape of a three-axis test table. The result shows that the method converges well, and the system is stable and reliable. 展开更多
关键词 Shape optimization Penalty function method Sensitivity analysis Integrated shape optimization system
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基于Flow-3D的液舱晃荡载荷流固耦合映射方法 认领 引用
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作者 程成 陆芝庆 +3 位作者 郭伟 陈康 刘德丰 黄翀 《中国舰船研究》 CSCD 北大核心 2026年第3期26-35,共10页
[目的]液舱晃荡载荷的传递是液货船流固耦合(FSI)仿真的关键,目前尚未形成较为通用的映射方法和独立的工具,为此,提出一种流体载荷快速向结构模型映射的方法。[方法]通过对晃荡载荷预报软件和结构强度计算软件的分析,明确这2种软件的数... [目的]液舱晃荡载荷的传递是液货船流固耦合(FSI)仿真的关键,目前尚未形成较为通用的映射方法和独立的工具,为此,提出一种流体载荷快速向结构模型映射的方法。[方法]通过对晃荡载荷预报软件和结构强度计算软件的分析,明确这2种软件的数据传递格式,提出3种兼顾效率和精度的晃荡载荷流固耦合映射方法,并研发独立的工具软件,形成一套完整的解决方案。[结果]实例验证表明,研发的工具能够高精度地实现载荷传递,在结构模型上能正确反映晃荡载荷演化的趋势及细节特征,3种映射方法的数据传递误差均小于5%。[结论]研发的映射工具可以作为通用的晃荡载荷流固耦合工具应用于液货船多物理场耦合分析及结构优化等场景中,可以大大提高工程人员的工作效率。 展开更多
关键词 液货舱 晃荡载荷 流固耦合 映射算法 形函数
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基于改进AMDM的弹性边界变截面Timoshenko梁自由振动分析 认领 引用
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作者 姚东辉 任勇生 张金峰 《湖南大学学报（自然科学版）》 EI CAS CSCD 北大核心 2026年第4期111-121,共11页
为改善Adomian修正分解法(adomian modified decomposition method,AMDM)在求解弹性边界变截面Timoshenko梁振动微分方程时的收敛性,把自适应分段技术引入AMDM的计算流程,通过使截面形状相关项的Taylor级数积分绝对误差估计符合特定阈值... 为改善Adomian修正分解法(adomian modified decomposition method,AMDM)在求解弹性边界变截面Timoshenko梁振动微分方程时的收敛性,把自适应分段技术引入AMDM的计算流程,通过使截面形状相关项的Taylor级数积分绝对误差估计符合特定阈值,自动确定具有不同形状函数幂次和锥度的变截面梁分段长度与数量.分析了锥度、跨高比、形状函数幂次以及边界支承刚度对线性、幂函数和指数函数变截面梁固有频率的影响,并探讨了影响收敛性的因素.数值仿真显示,与传统AMDM相比,计算耗时在不同情形下缩短了46%~91%.计算结果与有限元仿真相比,误差不超过0.16%,验证了本文方法的有效性和准确性.研究表明,固有频率对跨高比敏感度从大到小依次为幂函数、线性和指数函数变截面梁;边界支承刚度的强弱决定了固有频率-锥度曲线的增减趋势. 展开更多
关键词 变截面 Timoshenko梁 边界条件 改进的AMDM 形状函数 固有频率
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低噪环形螺旋桨新参数化方法设计及其水动力噪声研究 认领 引用
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作者 刘鹏 李帅强 《中国舰船研究》 CSCD 北大核心 2026年第1期156-166,共11页
[目的]环形螺旋桨旋转形成的涡流分布于整个叶片,可有效防止梢涡泄出,使漩涡在水中快速消散,减少水动力噪声传播;然而,环形螺旋桨结构比较复杂,使用常规螺旋桨的建模方法难以对环形螺旋桨进行建模,因此需要研究环形螺旋桨的参数化建模... [目的]环形螺旋桨旋转形成的涡流分布于整个叶片,可有效防止梢涡泄出,使漩涡在水中快速消散,减少水动力噪声传播;然而,环形螺旋桨结构比较复杂,使用常规螺旋桨的建模方法难以对环形螺旋桨进行建模,因此需要研究环形螺旋桨的参数化建模方程。[方法]引入螺旋桨轴距的概念,将环形螺旋桨的数学建模方程表示为随轴距变化的函数关系。定义与环形螺旋桨坐标系xy平面夹角为α的基准面,确保环形螺旋桨的参考线位于与旋转轴成α的基准面上,以该参考线为基准,基于类−形函数转换法(CST)构建沿参考线分布的NACA翼型,形成三叶环形螺旋桨模型。进一步引入FW−H声类比方程,对比环形螺旋桨和DTMB P4119螺旋桨的流场和非空化噪声。[结果]试验结果表明,相同推力条件下,环形螺旋桨的降噪效果显著优于DTMB P4119螺旋桨:在径向平面一定半径的圆周上,其各测点总噪声声压级比DTMB P4119螺旋桨降低约4 dB;在轴向平面一定半径的圆周上,各测点总噪声声压级比DTMB P4119螺旋桨降低4~6 dB。[结论]所提方法可为环形螺旋桨设计提供参考,全面分析与评估噪声水平,可为船舶和水下航行器等装备的水动力噪声抑制提供理论借鉴依据,同时为降低水下航行器和船舶的螺旋桨水动力噪声提供技术支撑。 展开更多
关键词 环形螺旋桨 水动力噪声 参数化 类−形函数 参考线 NACA翼型 FW−H声类比
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