Theoretical and Applied Mechanics Letters最新文献_第4页

Artificial boundary condition for Klein-Gordon equation by constructing mechanics structure 通过构造力学结构来求解Klein-Gordon方程的人工边界条件

IF 3.4 3区工程技术

Theoretical and Applied Mechanics Letters Pub Date : 2023-09-01 DOI: 10.1016/j.taml.2023.100459

Pang Gang , Zheng Zijun

引用次数: 0

Reseach on stability of laminated composite plate under nonlinear aerodynamic load 复合材料层合板在非线性气动载荷作用下的稳定性研究

IF 3.4 3区工程技术

Theoretical and Applied Mechanics Letters Pub Date : 2023-07-01 DOI: 10.1016/j.taml.2023.100461

The Van Tran , Quoc Hoa Pham , Nhan Thinh Hoang

引用次数: 0

The capillary pressure curves from upscaling interfacial and unsaturated flows in porous layers with vertical heterogeneity 纵向非均质多孔层中上尺度界面和非饱和流动的毛管压力曲线

IF 3.4 3区工程技术

Theoretical and Applied Mechanics Letters Pub Date : 2023-07-01 DOI: 10.1016/j.taml.2023.100467

Zhong Zheng

{"title":"The capillary pressure curves from upscaling interfacial and unsaturated flows in porous layers with vertical heterogeneity","authors":"Zhong Zheng","doi":"10.1016/j.taml.2023.100467","DOIUrl":"10.1016/j.taml.2023.100467","url":null,"abstract":"<div><p>We provide the capillary pressure curves <span><math><mrow><msub><mi>p</mi><mi>c</mi></msub><mrow><mo>(</mo><mover><mi>s</mi><mo>¯</mo></mover><mo>)</mo></mrow></mrow></math></span> as a function of the effective saturation <span><math><mover><mi>s</mi><mo>¯</mo></mover></math></span> based on the theoretical framework of upscaling unsaturated flows in vertically heterogeneous porous layers proposed recently in [1]. Based on the assumption of vertical gravitational-capillary equilibrium, the saturation distribution and profile shape of the invading fluid can be obtained by solving a nonlinear integral-differential equation. The capillary pressure curves <span><math><mrow><msub><mi>p</mi><mi>c</mi></msub><mrow><mo>(</mo><mover><mi>s</mi><mo>¯</mo></mover><mo>)</mo></mrow></mrow></math></span> can then be constructed by systematically varying the injection rate. Together with the relative permeability curves <span><math><mrow><msub><mover><mi>k</mi><mo>¯</mo></mover><mrow><mi>r</mi><mi>n</mi></mrow></msub><mrow><mo>(</mo><mover><mi>s</mi><mo>¯</mo></mover><mo>)</mo></mrow></mrow></math></span> that are already obtained in <span>[1]</span>, one can now provide quick estimates on the overall behaviours of interfacial and unsaturated flows in vertically-heterogeneous porous layers.</p></div>","PeriodicalId":46902,"journal":{"name":"Theoretical and Applied Mechanics Letters","volume":"13 4","pages":"Article 100467"},"PeriodicalIF":3.4,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41796130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Torsional postbuckling characteristics of functionally graded graphene enhanced laminated truncated conical shell with temperature dependent material properties 具有温度相关材料特性的功能梯度石墨烯增强层合截锥壳的扭转后屈曲特性

IF 3.4 3区工程技术

Theoretical and Applied Mechanics Letters Pub Date : 2023-07-01 DOI: 10.1016/j.taml.2023.100453

Hamad M. Hasan , Saad S. Alkhfaji , Sattar A. Mutlag

{"title":"Torsional postbuckling characteristics of functionally graded graphene enhanced laminated truncated conical shell with temperature dependent material properties","authors":"Hamad M. Hasan , Saad S. Alkhfaji , Sattar A. Mutlag","doi":"10.1016/j.taml.2023.100453","DOIUrl":"10.1016/j.taml.2023.100453","url":null,"abstract":"<div><p>Buckling and postbuckling characteristics of laminated graphene-enhanced composite (GEC) truncated conical shells exposed to torsion under temperature conditions using finite element method (FEM) simulation are presented in this study. In the thickness direction, the GEC layers of the conical shell are ordered in a piece-wise arrangement of functionally graded (FG) distribution, with each layer containing a variable volume fraction for graphene reinforcement. To calculate the properties of temperature-dependent material of GEC layers, the extended Halpin-Tsai micromechanical framework is used. The FEM model is verified via comparing the current results obtained with the theoretical estimates for homogeneous, laminated cylindrical, and conical shells, the FEM model is validated. The computational results show that a piece-wise FG graphene volume fraction distribution can improve the torque of critical buckling and torsional postbuckling strength. Also, the geometric parameters have a critical impact on the stability of the conical shell. However, a temperature rise can reduce the crucial torsional buckling torque as well as the GEC laminated truncated conical shell's postbuckling strength.</p></div>","PeriodicalId":46902,"journal":{"name":"Theoretical and Applied Mechanics Letters","volume":"13 4","pages":"Article 100453"},"PeriodicalIF":3.4,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46691188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An overview of fluids mixing in T-shaped mixers t形混合器中流体混合的概述

IF 3.4 3区工程技术

Theoretical and Applied Mechanics Letters Pub Date : 2023-07-01 DOI: 10.1016/j.taml.2023.100466

Huixin Li , Duo Xu

引用次数: 0

Reconstructing urban wind flows for urban air mobility using reduced-order data assimilation 利用降阶数据同化重建城市气流以实现城市空气流动

IF 3.4 3区工程技术

Theoretical and Applied Mechanics Letters Pub Date : 2023-07-01 DOI: 10.1016/j.taml.2023.100451

Mounir Chrit

{"title":"Reconstructing urban wind flows for urban air mobility using reduced-order data assimilation","authors":"Mounir Chrit","doi":"10.1016/j.taml.2023.100451","DOIUrl":"10.1016/j.taml.2023.100451","url":null,"abstract":"<div><p>Advancements in uncrewed aircrafts and communications technologies have led to a wave of interest and investment in unmanned aircraft systems (UASs) and urban air mobility (UAM) vehicles over the past decade. To support this emerging aviation application, concepts for UAS/UAM traffic management (UTM) systems have been explored. Accurately characterizing and predicting the microscale weather conditions, winds in particular, will be critical to safe and efficient operations of the small UASs/UAM aircrafts within the UTM. This study implements a reduced order data assimilation approach to reduce discrepancies between the predicted urban wind speed with computational fluid dynamics (CFD) Reynolds-averaged Navier Stokes (RANS) model with real-world, limited and sparse observations. The developed data assimilation system is UrbanDA. These observations are simulated using a large eddy simulation (LES). The data assimilation approach is based on the time-independent variational framework and uses space reduction to reduce the memory cost of the process. This approach leads to error reduction throughout the simulated domain and the reconstructed field is different than the initial guess by ingesting wind speeds at sensor locations and hence taking into account flow unsteadiness in a time when only the mean flow quantities are resolved. Different locations where wind sensors can be installed are discussed in terms of their impact on the resulting wind field. It is shown that near-wall locations, near turbulence generation areas with high wind speeds have the highest impact. Approximating the model error with its principal mode provides a better agreement with the truth and the hazardous areas for UAS navigation increases by more than 10% as wind hazards resulting from buildings wakes are better simulated through this process.</p></div>","PeriodicalId":46902,"journal":{"name":"Theoretical and Applied Mechanics Letters","volume":"13 4","pages":"Article 100451"},"PeriodicalIF":3.4,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48234507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Assessment of the stiffened panel performance in the OTEC seawater tank design: Parametric study and sensitivity analysis OTEC海水箱加劲板性能评估:参数化研究与敏感性分析

IF 3.4 3区工程技术

Theoretical and Applied Mechanics Letters Pub Date : 2023-07-01 DOI: 10.1016/j.taml.2023.100452

Yogie Muhammad Lutfi , Ristiyanto Adiputra , Aditya Rio Prabowo , Tomoaki Utsunomiya , Erwandi Erwandi , Nurul Muhayat

{"title":"Assessment of the stiffened panel performance in the OTEC seawater tank design: Parametric study and sensitivity analysis","authors":"Yogie Muhammad Lutfi , Ristiyanto Adiputra , Aditya Rio Prabowo , Tomoaki Utsunomiya , Erwandi Erwandi , Nurul Muhayat","doi":"10.1016/j.taml.2023.100452","DOIUrl":"10.1016/j.taml.2023.100452","url":null,"abstract":"<div><p>Ocean thermal energy conversion (OTEC) is a process of generating electricity by exploiting the temperature difference between warm surface seawater and cold deep seawater. Due to the high static and dynamic pressures that are caused by seawater circulation, the stiffened panel that constitutes a seawater tank may undergo a reduction in ultimate strength. The current paper investigates the design of stiffening systems for OTEC seawater tanks by examining the effects of stiffening parameters such as stiffener sizes and span-over-bay ratio for the applied combined loadings of lateral and transverse pressure by fluid motion and axial compression due to global bending moment. The ultimate strength calculation was conducted by using the non-linear finite element method via the commercial software known as ABAQUS. The stress and deformation distribution due to pressure loads was computed in the first step and then brought to the second step, in which the axial compression was applied. The effects of pressure on the ultimate strength of the stiffener were investigated for representative stiffened panels, and the significance of the stiffener parameters was assessed by using the sensitivity analysis method. As a result, the ultimate strength was reduced by approximately 1.5% for the span-over-bay ratio of 3 and by 7% for the span-over-bay ratio of 6.</p></div>","PeriodicalId":46902,"journal":{"name":"Theoretical and Applied Mechanics Letters","volume":"13 4","pages":"Article 100452"},"PeriodicalIF":3.4,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47601183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

Effects of mean shear on the vortex identification and the orientation statistics 平均切变对涡旋识别和方向统计的影响

IF 3.4 3区工程技术

Theoretical and Applied Mechanics Letters Pub Date : 2023-07-01 DOI: 10.1016/j.taml.2023.100454

Tianyi Bai , Cheng Cheng , Lin Fu

{"title":"Effects of mean shear on the vortex identification and the orientation statistics","authors":"Tianyi Bai , Cheng Cheng , Lin Fu","doi":"10.1016/j.taml.2023.100454","DOIUrl":"10.1016/j.taml.2023.100454","url":null,"abstract":"<div><p>This work compares the threshold applied to the swirling strength as well as the vortex orientation statistics in the total and fluctuating velocity fields using direct numerical simulations of compressible and incompressible turbulent channel flows. It is concluded that the difference in the swirling strength for vortex identification is minimal in the logarithmic region such that these two situations share the same threshold. Regarding the vortex orientation, the inclination angle remains similar. However, as the wall-normal distance increases, a more and more obvious distinction is noticed for its orientation with respect to the spanwise (<span><math><mi>z</mi></math></span>) direction. It is mainly due to their intrinsic differences and attendant contrasting preference for the vortex identification, i.e., vortices rotating in the <span><math><mrow><mo>−</mo><mi>z</mi></mrow></math></span> direction for the total velocity field and in the <span><math><mi>z</mi></math></span> direction for the fluctuating one. These observations function as a reasonable explanation for various remarks in previous studies.</p></div>","PeriodicalId":46902,"journal":{"name":"Theoretical and Applied Mechanics Letters","volume":"13 4","pages":"Article 100454"},"PeriodicalIF":3.4,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48884157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Advance on stochastic dynamics/nonlinear and stochastic dynamics 随机动力学/非线性和随机动力学研究进展

IF 3.4 3区工程技术

Theoretical and Applied Mechanics Letters Pub Date : 2023-07-01 DOI: 10.1016/j.taml.2023.100457

Yong Xu, Yongge Li, Stefano Lenci

引用次数: 0

Improving energy storage by PCM using hybrid nanofluid [(SWCNTs-CuO)/H2O] and a helical (spiral) coil: Hybrid passive techniques 使用混合纳米流体[（SWCNTs-CuO）/H2O]和螺旋（螺旋）线圈通过PCM改善储能：混合无源技术

IF 3.4 3区工程技术

Theoretical and Applied Mechanics Letters Pub Date : 2023-07-01 DOI: 10.1016/j.taml.2023.100458

Aliakbar Hosseinpour , Mohsen Pourfallah , Mosayeb Gholinia

引用次数: 1