Engineering Computations最新文献_第5页

Computational approach and convergence analysis for interval-based solution of the Benjamin–Bona–Mahony equation with imprecise parameters 参数不精确的本杰明-博纳-马霍尼方程基于区间求解的计算方法和收敛性分析

IF 1.6 4区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Engineering Computations

Pub Date : 2024-06-07 DOI: 10.1108/ec-12-2023-0905

Rambabu Vana, Karunakar Perumandla

Purpose

To provide a new semi-analytical solution for the nonlinear Benjamin–Bona–Mahony (BBM) equation in the form of a convergent series. The results obtained through HPTM for BBM are compared with those obtained using the Sine-Gordon Expansion Method (SGEM) and the exact solution. We consider the initial condition as uncertain, represented in terms of an interval then investigate the solution of the interval Benjamin–Bona–Mahony (iBBM).

Design/methodology/approach

We employ the Homotopy Perturbation Transform Method (HPTM) to derive the series solution for the BBM equation. Furthermore, the iBBM equation is solved using HPTM to the initial condition has been considered as an interval number as the coefficient of it depends on several parameters and provides lower and upper interval solutions for iBBM.

Findings

The obtained numerical results provide accurate solutions, as demonstrated in the figures. The numerical results are evaluated to the precise solutions and found to be in good agreement. Further, the initial condition has been considered as an interval number as the coefficient of it depends on several parameters. To enhance the clarity, we depict our solutions using 3D graphics and interval solution plots generated using MATLAB.

Originality/value

A new semi-analytical convergent series-type solution has been found for nonlinear BBM and interval BBM equations with the help of the semi-analytical technique HPTM.

目的以收敛级数形式为非线性本杰明-博纳-马霍尼（BBM）方程提供一种新的半解析解。将通过 BBM 的 HPTM 方法获得的结果与使用正弦-戈登展开法 (SGEM) 和精确解法获得的结果进行比较。我们将初始条件视为不确定条件，用区间表示，然后研究区间本杰明-博纳-马霍尼（iBBM）方程的解。此外，由于 iBBM 的系数取决于多个参数，因此初始条件被视为区间数，我们采用 HPTM 方法求解了 iBBM 方程，并为 iBBM 提供了下区间和上区间解。根据精确解对数值结果进行了评估，发现两者非常吻合。此外，初始条件被视为区间数，因为其系数取决于多个参数。为了提高清晰度，我们使用 MATLAB 生成的三维图形和区间解图来描述我们的解。

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引用次数: 0

A generic numerical method for treating a system of Volterra integro-differential equations with multiple delays and variable bounds 处理具有多重延迟和变量边界的 Volterra 积分微分方程系统的通用数值方法

IF 1.6 4区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Engineering Computations

Pub Date : 2024-06-06 DOI: 10.1108/ec-09-2023-0590

Ömür Kıvanç Kürkçü, Mehmet Sezer

Purpose

This study aims to treat a novel system of Volterra integro-differential equations with multiple delays and variable bounds, constituting a generic numerical method based on the matrix equation and a combinatoric-parametric Charlier polynomials. The proposed method utilizes these polynomials for the matrix relations at the collocation points.

Design/methodology/approach

Thanks to the combinatorial eligibility of the method, the functional terms can be transformed into the generic matrix relations with low dimensions, and their resulting matrix equation. The obtained solutions are tested with regard to the parametric behaviour of the polynomials with $alpha$, taking into account the condition number of an outcome matrix of the method. Residual error estimation improves those solutions without using any external method. A calculation of the residual error bound is also fulfilled.

Findings

All computations are carried out by a special programming module. The accuracy and productivity of the method are scrutinized via numerical and graphical results. Based on the discussions, one can point out that the method is very proper to solve a system in question.

Originality/value

This paper introduces a generic computational numerical method containing the matrix expansions of the combinatoric Charlier polynomials, in order to treat the system of Volterra integro-differential equations with multiple delays and variable bounds. Thus, the method enables to evaluate stiff differential and integral parts of the system in question. That is, these parts generates two novel components in terms of unknown terms with both differentiated and delay arguments. A rigorous error analysis is deployed via the residual function. Four benchmark problems are solved and interpreted. Their graphical and numerical results validate accuracy and efficiency of the proposed method. In fact, a generic method is, thereby, provided into the literature.

目的本研究旨在处理一个具有多重延迟和变量边界的新型 Volterra 积分微分方程系统，构成一种基于矩阵方程和组合参数 Charlier 多项式的通用数值方法。设计/方法/途径由于该方法的组合资格，函数项可以转化为低维度的通用矩阵关系，以及由此产生的矩阵方程。在考虑到该方法结果矩阵的条件数的情况下，对所获得的解决方案进行了$α$多项式参数行为测试。残余误差估计无需使用任何外部方法即可改进这些解。所有计算均由一个特殊的编程模块完成。所有计算均由一个专门的编程模块完成，并通过数值和图形结果对该方法的准确性和效率进行了仔细检查。原创性/价值本文介绍了一种通用计算数值方法，该方法包含组合夏利耶多项式的矩阵展开，用于处理具有多重延迟和变量边界的 Volterra 微分方程系统。因此，该方法能够评估相关系统的刚性微分和积分部分。也就是说，这些部分产生了两个新的组成部分，即具有微分和延迟参数的未知项。通过残差函数进行严格的误差分析。对四个基准问题进行了求解和解释。其图形和数值结果验证了所提方法的准确性和效率。事实上，这也为文献提供了一种通用方法。

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引用次数: 0

Investigation of the influence of plane strain constrained anisotropic plastic flow on the localized necking prediction 平面应变约束各向异性塑性流动对局部缩颈预测影响的研究

IF 1.6 4区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Engineering Computations

Pub Date : 2024-06-04 DOI: 10.1108/ec-06-2023-0273

Bora Şener

Purpose

The purpose of this manuscript is to investigate the influence of the satisfying of plane strain conditions on the prediction of the localized necking and to evaluate this effect by the different hardening models.

Design/methodology/approach

High-order anisotropic Drucker yield function, two types of hardening models, namely Hollomon power and Voce saturated, and the modified maximum force criterion (MMFC) are employed to predict the forming limit strains of AA3104-H19 alloy. Two identification methods, namely conventional and plane strain constrained, are applied and forming limit diagrams of the material are predicted by the incorporation of the anisotropic Drucker criterion and the hardening models into the MMFC for both calibration methods.

Findings

The enhancement in the prediction accuracy of the forming limits provided by the implementation of the plane strain constrained method is strongly dependent upon the selected hardening model type in the MMFC. About 18% improvement in the prediction of the biaxial limit strains is provided via Hollomon power law hardening, whereas the opposite result is occurred in case that the Voce saturated hardening law is used, and the predictions match with the experimental data only in the plane strain point and its surroundings.

Originality/value

The plane strain constrained identification method precisely predicts the location of the plane strain point on the yield locus and also any yield stress or anisotropy coefficient in the plane strain state is not required during the calibration, therefore the method can reduce the number of the required experiments for the constitutive characterization, and it will be attractive for both academy and industry. Additionally, the improvement in the prediction of the biaxial forming limits can be provided by applying of this method along with the appropriate hardening law.

本文旨在研究满足平面应变条件对局部缩颈预测的影响，并通过不同的硬化模型评估这种影响。本文采用了高阶各向异性德鲁克屈服函数、两种硬化模型（即霍洛蒙功率模型和 Voce 饱和模型）以及修正的最大力准则（MMFC）来预测 AA3104-H19 合金的成形极限应变。应用了两种识别方法，即传统方法和平面应变约束方法，并通过将各向异性的德鲁克准则和硬化模型纳入这两种校准方法的 MMFC 来预测材料的成形极限图。采用霍洛蒙幂律淬火法时，双轴极限应变的预测结果提高了约 18%，而采用 Voce 饱和淬火法时，结果则相反，预测结果仅在平面应变点及其周围与实验数据相符。原创性/价值平面应变约束识别方法可以精确预测屈服点上平面应变点的位置，而且在校准过程中不需要任何平面应变状态下的屈服应力或各向异性系数，因此该方法可以减少构件表征所需的实验数量，对学术界和工业界都有吸引力。此外，通过应用该方法和适当的硬化定律，还能改善双轴成形极限的预测。

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引用次数: 0

Improving stability and adaptability of automotive electric steering systems based on a novel optimal integrated algorithm 基于新型优化集成算法提高汽车电动转向系统的稳定性和适应性

IF 1.6 4区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Engineering Computations

Pub Date : 2024-06-04 DOI: 10.1108/ec-10-2023-0675

Tuan Anh Nguyen, Jamshed Iqbal

Purpose

Design a novel optimal integrated control algorithm for the automotive electric steering system to improve the stability and adaptation of the system.

Design/methodology/approach

Simulation and calculation.

Findings

The output signals follow the reference signal with high accuracy.

Originality/value

The optimal integrated algorithm is established based on the combination of PID and SMC. The parameters of the PID controller are adjusted using a fuzzy algorithm. The optimal range of adjustment values is determined using a genetic algorithm.

目的为汽车电动转向系统设计一种新颖的优化集成控制算法，以提高系统的稳定性和适应性。使用模糊算法调整 PID 控制器的参数。利用遗传算法确定了最佳调整值范围。

引用次数: 0

Size-dependent finite element analysis of FGMs in thermal environment based on the modified couple stress theory 基于修正耦合应力理论的热环境中取决于尺寸的 FGM 有限元分析

IF 1.6 4区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Engineering Computations

Pub Date : 2024-06-04 DOI: 10.1108/ec-10-2023-0666

Songhao Wang, Zhenghua Qian, Yan Shang

Purpose

The paper aims to the size-dependent analysis of functionally graded materials in thermal environment based on the modified couple stress theory using finite element method.

Design/methodology/approach

The element formulation is developed within the framework of the penalty unsymmetric finite element method (FEM) in that the C¹ continuity requirement is satisfied in weak sense and thus, C⁰ continuous interpolation enhanced by independent nodal rotation is employed as the test function. Meanwhile, the trial function is designed based on the stress functions and the weighted residual method. Besides, the special Gauss quadrature scheme is employed for integrals of matrices in accordance with the graded variation of the material properties.

Findings

The numerical results reveal that in thermal environment, functionally graded materials exhibit better bending performance compared to homogeneous materials, Moreover, the findings also indicate that with an increase in MLSP, the natural frequencies of out-of-plane modes gradually increase, while the natural frequencies of in-plane modes show much less variation, leading to a mode switch phenomenon.

Originality/value

The work provides an efficient numerical tool for analyzing and designing the functionally graded structures in thermal environment in practical engineering applications.

设计/方法/途径在罚非对称有限元法（FEM）的框架内开发了元素配方，在弱意义上满足 C1 连续性要求，因此采用独立节点旋转增强的 C0 连续插值作为试验函数。同时，试验函数是根据应力函数和加权残差法设计的。数值结果表明，在热环境下，与均质材料相比，功能分级材料表现出更好的弯曲性能。此外，研究结果还表明，随着 MLSP 的增加，平面外模态的固有频率逐渐增加，而平面内模态的固有频率变化较小，从而导致模态切换现象。原创性/价值这项研究为实际工程应用中热环境下功能分级结构的分析和设计提供了有效的数值工具。

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引用次数: 0

Artificial intelligence schemes to predict the mechanical performance of lignocellulosic fibers with unseen data to enhance the reliability of biocomposites 利用未见数据预测木质纤维素纤维机械性能的人工智能方案，提高生物复合材料的可靠性

IF 1.6 4区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Engineering Computations

Pub Date : 2024-06-04 DOI: 10.1108/ec-11-2023-0882

Rami Al-Jarrah, Faris M. AL-Oqla

Purpose

This work introduces an integrated artificial intelligence schemes to enhance accurately predicting the mechanical properties of cellulosic fibers towards boosting their reliability for more sustainable industries.

Design/methodology/approach

Fuzzy clustering and stacked method approach were utilized to predict the mechanical performance of the fibers. A reference dataset contains comprehensive information regarding mechanical behavior of the lignocellulosic fibers was compiled from previous experimental investigations on mechanical properties for eight different fiber materials. Data encompass three key factors: Density of 0.9–1.6 g/cm³, Diameter of 5.9–1,000 µm, and Microfibrillar angle of 2–49 deg were utilized. Initially, fuzzy clustering technique was utilized for the data. For validating proposed model, ultimate tensile strength and elongation at break were predicted and then examined against unseen new data that had not been used during model development.

Findings

The output results demonstrated remarkably accurate and highly acceptable predictions results. The error analysis for the proposed method was discussed by using statistical criteria. The stacked model proved to be effective in significantly reducing level of uncertainty in predicting the mechanical properties, thereby enhancing model’s reliability and precision. The study demonstrates the robustness and efficacy of the stacked method in accurately estimating mechanical properties of lignocellulosic fibers, making it a valuable tool for material scientists and engineers in various applications.

Originality/value

Cellulosic fibers are essential for biomaterials to enhance developing green sustainable bio-products. However, such fibers have diverse characteristics according to their types, chemical composition and structure causing inconsistent mechanical performance. This work introduces an integrated artificial intelligence schemes to enhance accurately predicting the mechanical properties of cellulosic fibers towards boosting their reliability for more sustainable industries. Fuzzy clustering and stacked method approach were utilized to predict the mechanical performance of the fibers.

设计/方法/方法利用模糊聚类和堆叠法预测纤维的机械性能。参考数据集包含有关木质纤维素纤维机械性能的全面信息，该数据集是从以前对八种不同纤维材料的机械性能进行的实验研究中整理出来的。数据包含三个关键因素：密度为 0.9-1.6 g/cm3，直径为 5.9-1,000 µm，微纤维角度为 2-49 deg。最初，对数据采用了模糊聚类技术。为了验证所提出的模型，对极限拉伸强度和断裂伸长率进行了预测，然后根据模型开发过程中未使用过的新数据进行了检验。使用统计标准讨论了所提方法的误差分析。事实证明，叠加模型能有效降低机械性能预测的不确定性，从而提高模型的可靠性和精确度。该研究证明了堆叠法在准确估算木质纤维素纤维机械性能方面的稳健性和有效性，使其成为材料科学家和工程师在各种应用中的宝贵工具。然而，此类纤维因其类型、化学成分和结构而具有不同的特性，导致其机械性能不一致。这项工作介绍了一种综合人工智能方案，以提高对纤维素纤维机械性能的准确预测，从而增强纤维素纤维的可靠性，促进工业的可持续发展。模糊聚类和堆叠法被用来预测纤维的机械性能。

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引用次数: 0

Multiscale stochastic optimal control of hysteretic structures based on wavelet transform and probability density evolution method 基于小波变换和概率密度演化法的滞回结构多尺度随机优化控制

IF 1.6 4区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Engineering Computations

Pub Date : 2024-05-31 DOI: 10.1108/ec-10-2023-0704

Haylim Chha, Yongbo Peng

Purpose

Contemporary stochastic optimal control by synergy of the probability density evolution method (PDEM) and conventional optimal controller exhibits less capability to guarantee economical energy consumption versus control efficacy when non-stationary stochastic excitations drive hysteretic structures. In this regard, a novel multiscale stochastic optimal controller is invented based on the wavelet transform and the PDEM.

Design/methodology/approach

For a representative point, a conventional control law is decomposed into sub-control laws by deploying the multiresolution analysis. Then, the sub-control laws are classified into two generic control laws using resonant and non-resonant bands. Both frequency bands are established by employing actual natural frequency(ies) of structure, making computed efforts depend on actual structural properties and time-frequency effect of non-stationary stochastic excitations. Gain matrices in both bands are then acquired by a probabilistic criterion pertaining to system second-order statistics assessment. A multi-degree-of-freedom hysteretic structure driven by non-stationary and non-Gaussian stochastic ground accelerations is numerically studied, in which three distortion scenarios describing uncertainties in structural properties are considered.

Findings

Time-frequency-dependent gain matrices sophisticatedly address non-stationary stochastic excitations, providing efficient ways to independently suppress vibrations between resonant and non-resonant bands. Wavelet level, natural frequency(ies), and ratio of control forces in both bands influence the scheme’s outcomes. Presented approach outperforms existing approach in ensuring trade-off under uncertainty and randomness in system and excitations.

Originality/value

Presented control law generates control efforts relying upon resonant and non-resonant bands, and deploys actual structural properties. Cost-function weights and probabilistic criterion are promisingly developed, achieving cost-effectiveness of energy demand versus controlled structural performance.

目的当非稳态随机激励驱动滞后结构时，通过概率密度演化法（PDEM）和传统优化控制器协同作用实现的当代随机优化控制在保证经济能耗和控制效果方面表现出较低的能力。为此，基于小波变换和 PDEM 发明了一种新型多尺度随机优化控制器。然后，利用共振频率带和非共振频率带将子控制法则分为两种通用控制法则。这两个频段都是利用结构的实际固有频率建立的，因此计算工作取决于实际结构特性和非稳态随机激励的时频效应。然后，通过与系统二阶统计评估相关的概率标准来获取两个频段的增益矩阵。对由非稳态和非高斯随机地面加速度驱动的多自由度滞变结构进行了数值研究，其中考虑了描述结构特性不确定性的三种变形情况。两个波段的小波级别、固有频率和控制力比率都会影响方案的结果。所提出的方法在确保系统和激励的不确定性和随机性条件下的权衡方面优于现有方法。原创性/价值所提出的控制法则依靠共振带和非共振带产生控制力，并利用实际结构特性。成本函数权重和概率标准的开发前景广阔，实现了能源需求与受控结构性能的成本效益。

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引用次数: 0

Design and optimization of a domestic solar dryer: an analytical approach 家用太阳能干燥器的设计与优化：一种分析方法

IF 1.6 4区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Engineering Computations

Pub Date : 2024-05-31 DOI: 10.1108/ec-12-2023-0916

Shimpy Shimpy, Mahesh Kumar, Anil Kumar

Purpose

Food loss and wastage is an issue of global concern and the household sector is one of the biggest contributors to this. Solar drying has been explored by many eminent researchers as a solution to this problem but there have been concerns about the lack in designs, higher cost, lower performance, and consumer acceptability. The present research aims to design a small-scale domestic solar dryer by using computer software.

Design/methodology/approach

Response surface methodology (RSM) and computational fluid dynamics (CFD) are used to design the domestic solar dryer. Initially, design variables (inlet and outlet vent height) are identified and a design of experiments has been created using RSM for set of experimental runs. The experimental runs suggested by RSM were carried out using CFD simulation in COMSOL Multiphysics software and the results were used for optimization of response variables (outlet velocity and drying chamber temperature) in RSM.

Findings

Outlet vent height was found to be most significantly affecting parameter to both the responses. The optimum values of inlet and outlet vent heights were 0.5 and 2.5 cm, respectively with the overall desirability of 0.728. The model accuracy was tested by conducting a confirmation test as post processing in design expert software.

Originality/value

Designing a solar dryer is a complex, costly and time consuming process, this study presents an easy, economic and fast method to design a new solar dryer. It would help researchers to design and develop new domestic as well as large size industrial solar dryer.

目的粮食损失和浪费是一个全球关注的问题，而家庭部门是造成这一问题的最大因素之一。许多知名研究人员已经探索出太阳能干燥作为解决这一问题的方法，但人们对设计不足、成本较高、性能较差和消费者接受度等问题表示担忧。本研究旨在使用计算机软件设计一种小型家用太阳能干燥器。设计/方法/途径采用响应面方法学（RSM）和计算流体动力学（CFD）设计家用太阳能干燥器。首先，确定了设计变量（入口和出口通风口高度），并使用 RSM 为一组实验运行创建了实验设计。使用 COMSOL Multiphysics 软件中的 CFD 仿真对 RSM 建议的实验运行进行了模拟，并将结果用于 RSM 中响应变量（出口速度和干燥室温度）的优化。入口和出口通风口高度的最佳值分别为 0.5 厘米和 2.5 厘米，总体可取性为 0.728。本研究提出了一种简便、经济、快速的方法来设计新型太阳能干燥器。这将有助于研究人员设计和开发新型家用和大型工业用太阳能干燥器。

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引用次数: 0

Application of Laplace Adomian decomposition method for fractional Fokker-Planck equation and time fractional coupled Boussinesq-Burger equations 分数 Fokker-Planck 方程和时间分数耦合 Boussinesq-Burger 方程的拉普拉斯-阿多米安分解法的应用

IF 1.6 4区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Engineering Computations

Pub Date : 2024-05-09 DOI: 10.1108/ec-06-2023-0275

Yufeng Zhang, Lizhen Wang

Purpose

Fractional Fokker-Planck equation (FFPE) and time fractional coupled Boussinesq-Burger equations (TFCBBEs) play important roles in the fields of solute transport, fluid dynamics, respectively. Although there are many methods for solving the approximate solution, simple and effective methods are more preferred. This paper aims to utilize Laplace Adomian decomposition method (LADM) to construct approximate solutions for these two types of equations and gives some examples of numerical calculations, which can prove the validity of LADM by comparing the error between the calculated results and the exact solution.

Design/methodology/approach

This paper analyzes and investigates the time-space fractional partial differential equations based on the LADM method in the sense of Caputo fractional derivative, which is a combination of the Laplace transform and the Adomian decomposition method. LADM method was first proposed by Khuri in 2001. Many partial differential equations which can describe the physical phenomena are solved by applying LADM and it has been used extensively to solve approximate solutions of partial differential and fractional partial differential equations.

Findings

This paper obtained an approximate solution to the FFPE and TFCBBEs by using the LADM. A number of numerical examples and graphs are used to compare the errors between the results and the exact solutions. The results show that LADM is a simple and effective mathematical technique to construct the approximate solutions of nonlinear time-space fractional equations in this work.

Originality/value

This paper verifies the effectiveness of this method by using the LADM to solve the FFPE and TFCBBEs. In addition, these two equations are very meaningful, and this paper will be helpful in the study of atmospheric diffusion, shallow water waves and other areas. And this paper also generalizes the drift and diffusion terms of the FFPE equation to the general form, which provides a great convenience for our future studies.

目的分数福克-普朗克方程（FFPE）和时间分数耦合布辛斯克-伯格方程（TFCBBE）分别在溶质输运和流体动力学领域发挥着重要作用。虽然求解近似解的方法很多，但简单有效的方法更受青睐。本文旨在利用拉普拉斯-阿多米安分解法（LADM）来构建这两类方程的近似解，并给出了一些数值计算实例，通过比较计算结果与精确解之间的误差来证明 LADM 的有效性。设计/方法/途径本文基于 Caputo 分导数意义上的 LADM 方法对时空分式偏微分方程进行了分析和研究，LADM 方法是拉普拉斯变换与阿多米安分解法的结合。LADM 方法由 Khuri 于 2001 年首次提出。许多能描述物理现象的偏微分方程都是通过应用 LADM 来求解的，它已被广泛用于求解偏微分方程和分数偏微分方程的近似解。文中使用了大量数值示例和图表来比较结果与精确解之间的误差。结果表明，LADM 是构建非线性时空分式方程近似解的一种简单而有效的数学技术。此外，这两个方程非常有意义，本文将有助于大气扩散、浅水波等领域的研究。而且本文还将 FFPE 方程的漂移项和扩散项概括为一般形式，为我们今后的研究提供了极大的便利。

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引用次数: 0

A new fast four-point rainflow cycle counting algorithm by employing a new loop iteration mode for fatigue life estimation 采用新循环迭代模式的新型快速四点雨流循环计数算法，用于疲劳寿命估算

IF 1.6 4区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Engineering Computations

Pub Date : 2024-05-07 DOI: 10.1108/ec-11-2023-0814

Gangting Huang, Qichen Wu, Youbiao Su, Yunfei Li, Shilin Xie

Purpose

In order to improve the computation efficiency of the four-point rainflow algorithm, a new fast four-point rainflow cycle counting algorithm (FFRA) using a novel loop iteration mode is proposed.

Design/methodology/approach

In this new algorithm, the loop iteration mode is simplified by reducing the number of iterations, tests and deletions. The high efficiency of the new algorithm makes it a preferable candidate in fatigue life online estimation of structural health monitoring systems.

Findings

The extensive simulation results show that the extracted cycles by the new FFRA are the same as those by the four-point rainflow cycle counting algorithm (FRA) and the three-point rainflow cycle counting algorithm (TRA). Especially, the simulation results indicate that the computation efficiency of the FFRA has improved an average of 12.4 times compared to the FRA and an average of 8.9 times compared to the TRA. Moreover, the equivalence of cycle extraction results between the FFRA and the FRA is proved mathematically by utilizing some fundamental properties of the rainflow algorithm. Theoretical proof of the efficiency improvement of the FFRA in comparison to the FRA is also given.

Originality/value

This merit makes the FFRA preferable in online monitoring systems of structures where fatigue life estimation needs to be accomplished online based on massive measured data. It is noticeable that the high efficiency of the FFRA attributed to the simple loop iteration, which provides beneficial guidance to improve the efficiency of existing algorithms.

目的为了提高四点雨流算法的计算效率，提出了一种采用新型循环迭代模式的新型快速四点雨流循环计数算法（FFRA）。研究结果大量仿真结果表明，新的 FFRA 算法提取的循环次数与四点雨流循环计数算法（FRA）和三点雨流循环计数算法（TRA）相同。尤其是仿真结果表明，FFRA 的计算效率比 FRA 平均提高了 12.4 倍，比 TRA 平均提高了 8.9 倍。此外，利用雨流算法的一些基本特性，从数学上证明了 FFRA 和 FRA 的循环提取结果是等价的。原创性/价值这一优点使 FFRA 成为结构在线监测系统的首选，在这种系统中，需要根据大量测量数据在线完成疲劳寿命估算。值得注意的是，FFRA 的高效率归功于简单的循环迭代，这为提高现有算法的效率提供了有益的指导。

{"title":"A new fast four-point rainflow cycle counting algorithm by employing a new loop iteration mode for fatigue life estimation","authors":"Gangting Huang, Qichen Wu, Youbiao Su, Yunfei Li, Shilin Xie","doi":"10.1108/ec-11-2023-0814","DOIUrl":"https://doi.org/10.1108/ec-11-2023-0814","url":null,"abstract":"<h3>Purpose</h3>\u0000<p> In order to improve the computation efficiency of the four-point rainflow algorithm, a new fast four-point rainflow cycle counting algorithm (FFRA) using a novel loop iteration mode is proposed.</p>\u0000<h3>Design/methodology/approach</h3>\u0000<p> In this new algorithm, the loop iteration mode is simplified by reducing the number of iterations, tests and deletions. The high efficiency of the new algorithm makes it a preferable candidate in fatigue life online estimation of structural health monitoring systems.</p>\u0000<h3>Findings</h3>\u0000<p> The extensive simulation results show that the extracted cycles by the new FFRA are the same as those by the four-point rainflow cycle counting algorithm (FRA) and the three-point rainflow cycle counting algorithm (TRA). Especially, the simulation results indicate that the computation efficiency of the FFRA has improved an average of 12.4 times compared to the FRA and an average of 8.9 times compared to the TRA. Moreover, the equivalence of cycle extraction results between the FFRA and the FRA is proved mathematically by utilizing some fundamental properties of the rainflow algorithm. Theoretical proof of the efficiency improvement of the FFRA in comparison to the FRA is also given.</p>\u0000<h3>Originality/value</h3>\u0000<p> This merit makes the FFRA preferable in online monitoring systems of structures where fatigue life estimation needs to be accomplished online based on massive measured data. It is noticeable that the high efficiency of the FFRA attributed to the simple loop iteration, which provides beneficial guidance to improve the efficiency of existing algorithms.</p>","PeriodicalId":50522,"journal":{"name":"Engineering Computations","volume":"10 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140831516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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