Applied Mathematics and Mechanics Pub Date : 2023-01-01 DOI: 10.21656/1000-0887.440029

Chen Huijian, Zhu Qingfeng, Miao Hongchen, Feng Zhiqiang

引用次数: 0

An Iterative Regularization Method for Solving Backward Problems With 2 Perturbation Data 一种求解双扰动数据倒推问题的迭代正则化方法

Applied Mathematics and Mechanics Pub Date : 2023-01-01 DOI: 10.21656/1000-0887.440066

YUAN Xiaoyu, FENG Xiaoli, ZHANG Yun

引用次数: 0

Multi-Scale Prediction of Thermal and Mechanical Properties of C/SiC Braided Composites C/SiC编织复合材料热力学性能的多尺度预测

Applied Mathematics and Mechanics Pub Date : 2023-01-01 DOI: 10.21656/1000-0887.440056

ZHANG Yongzheng, LIU Lei, LIU Qi, XU Guangkui

{"title":"Multi-Scale Prediction of Thermal and Mechanical Properties of C/SiC Braided Composites","authors":"ZHANG Yongzheng, LIU Lei, LIU Qi, XU Guangkui","doi":"10.21656/1000-0887.440056","DOIUrl":"https://doi.org/10.21656/1000-0887.440056","url":null,"abstract":"C/SiC composites have been widely used in aerospace, national defense, and chemical industries due to their excellent mechanical and thermal properties. Accurate knowledge about the mechanical/thermal properties of C/SiC composites is very important for their efficient application in related fields. Based on the representative volume element (RVE) and periodic boundary conditions, a micro/meso single-cell model for C/SiC composites was established in view of the non-uniform and multi-scale characteristics of fiber bundles, such as the volume fraction, the interweaving mode, and the weaving dimension. The finite element software ABAQUS was used to predict the micro-scale thermal and mechanical properties of the fiber bundle, and the fiber bundle properties were introduced into the mesoscopic model to analyze and obtain the macroscopic thermal and mechanical properties of the composite. Based on this multi-scale correlation analysis method, the thermal conductivity and thermal expansion coefficient of fiber bundles and C/SiC composites were further studied at the operating temperatures ranging from 27~1 227 ℃. The study has certain guiding significance for the application of C/SiC composites in engineering.","PeriodicalId":8341,"journal":{"name":"Applied Mathematics and Mechanics","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135505366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Breakup and Atomization Characteristics of Liquid Jets in Strong Swirling Crossflow Based on the VOF-LPT Method 基于VOF-LPT方法的强旋流中液体射流破碎与雾化特性研究

Applied Mathematics and Mechanics Pub Date : 2023-01-01 DOI: 10.21656/1000-0887.440110

XIE Mingyun, PU Tianhao, LIU Hong, WU Shengqi

{"title":"Breakup and Atomization Characteristics of Liquid Jets in Strong Swirling Crossflow Based on the VOF-LPT Method","authors":"XIE Mingyun, PU Tianhao, LIU Hong, WU Shengqi","doi":"10.21656/1000-0887.440110","DOIUrl":"https://doi.org/10.21656/1000-0887.440110","url":null,"abstract":"The liquid jet breakup and atomization interacting with a strong swirling crossflow is of significance in designing advanced aeroengines. The Eulerian-Lagrangian method was utilized to simulate the jet breakup and atomization processes. The volume of fluid (VOF) method was employed to track the gas-liquid interface topology evolution during the jet breakup, while the Lagrangian particle tracing (LPT) method was used to track the discrete droplets and obtain the information on far-field liquid dispersion. The crossflow was designed with different swirl numbers, ranging from 0 to 2.5. Momentum ratio q between the liquid jet and the air flow was set to 10, and the gas Weber number was 39. Under these conditions, both the column and shear breakups were observed. The results indicate that, the development of axial waves induced by the Kevin-Helmholtz (KH) instability was the main cause for column breakup. During the surface breakup, ligaments and small liquid jet branches were stripped from the liquid jet surface, primarily driven by azimuthal shear waves. The strong swirling airflow enhances the jet column breakup process, leading to a lower radial height for the breakup location and a shorter breakup time. However, as the swirl number increases, the radial height of the onset of breakup would increase, which suggests the swirl flow would delay the surface breakup of liquid jets. With the increase of the swirl number, the velocity component in the flow direction decreases, and the jet trajectory in the radial direction increases significantly. The deflection angle of the jet shows a linear relationship with the position of the flow direction, with larger air swirl numbers resulting in a steeper slope. Furthermore, as the swirl number increases, the Sauter mean diameter (SMD) of the entire spray field would decrease, and the liquid dispersion would increase.","PeriodicalId":8341,"journal":{"name":"Applied Mathematics and Mechanics","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135838476","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Mindlin-Medick Plate Theory and Its Application Under Flexoelectricity and Temperature Effects 挠性电和温度效应下的Mindlin-Medick板理论及其应用

Applied Mathematics and Mechanics Pub Date : 2023-01-01 DOI: 10.21656/1000-0887.440017

LU Shuang, LI Dongbo, CHEN Jingbo, XI Bo

{"title":"The Mindlin-Medick Plate Theory and Its Application Under Flexoelectricity and Temperature Effects","authors":"LU Shuang, LI Dongbo, CHEN Jingbo, XI Bo","doi":"10.21656/1000-0887.440017","DOIUrl":"https://doi.org/10.21656/1000-0887.440017","url":null,"abstract":"Based on the Hamiltonian variational principle, the 2D field equations and boundary conditions for flexoelectricity were derived, and the corresponding governing equations were obtained through substitution of the constitutive relation and geometric equations into the field equation. The in-plane tensile deformation, thickness-stretch deformation, symmetric thickness-shear deformation, and their coupled flexoelectric polarization of flexoelectric nanoplates caused by inhomogeneous temperature changes, were studied. The displacement fields and electric potential fields were solved with the double Fourier series method. The results demonstrate that, all fields are sensitive to the temperature load, which raises the prospect of controlling the mechanical and electrical behaviors of flexoelectric nanoplates by means of the temperature field. The effects of the thermal field and mechanical field on the displacement field were compared and examined. The work extends the Mindlin-Medick plate structure analysis theory in view of the flexoelectric and temperature effects, and provides a reference for the structural design of micro- and nano-scale devices.","PeriodicalId":8341,"journal":{"name":"Applied Mathematics and Mechanics","volume":"171 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135838483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Eulerian Finite-Element Numerical Simulation Investigation on the Dynamic Characteristics of Out-of-Phase Bubbles in Underwater Explosions 水下爆炸中非相气泡动态特性的欧拉有限元数值模拟研究

Applied Mathematics and Mechanics Pub Date : 2023-01-01 DOI: 10.21656/1000-0887.440047

TANG Hao, LIU Yunlong, FENG Jituan, JU Xinyang, ZHANG Aman

引用次数: 0

Energy Conservation of the 4 D Incompressible Navier-Stokes Equations 四维不可压缩Navier-Stokes方程的能量守恒

Applied Mathematics and Mechanics Pub Date : 2023-01-01 DOI: 10.21656/1000-0887.430370

WANG Bin, ZHOU Yanping, BIE Qunyi

引用次数: 0

Numerical Analysis of Flame Flashback and Instability in Cavity-Stabilized Supersonic Combustion 腔稳定超声速燃烧中火焰闪回与不稳定性的数值分析

Applied Mathematics and Mechanics Pub Date : 2023-01-01 DOI: 10.21656/1000-0887.440103

XIAO Yexin, JIN Tai

{"title":"Numerical Analysis of Flame Flashback and Instability in Cavity-Stabilized Supersonic Combustion","authors":"XIAO Yexin, JIN Tai","doi":"10.21656/1000-0887.440103","DOIUrl":"https://doi.org/10.21656/1000-0887.440103","url":null,"abstract":"Aimed at the phenomenon of flame flashback and low-frequency combustion oscillation in the scramjet combustor with equal straight cross sections, 3D simulations were conducted, with the hybrid RANS/LES method (delayed detached-eddy simulation, DDES) for turbulence modeling and the partially stirred reactor (PaSR) for turbulence-reaction interactions. The obtained entire combustion oscillation period is consistent with the low-frequency combustion oscillation phenomenon observed in the experiment. The low-frequency combustion oscillation period can be divided into 3 stages: the cavity-holding flame, the flame flashback, and the flame blowout. By analysis of the reacting flow field in different stages of the low-frequency combustion oscillation cycle, the possible formation mechanism of low-frequency combustion oscillations was summarized. The results show that, there is no choking in the combustion chamber during the whole low-frequency combustion oscillation period. The pressure rise induced by shock interaction and the heat released by combustion are the key factors for the formation of low-frequency combustion oscillations in the combustion chamber.","PeriodicalId":8341,"journal":{"name":"Applied Mathematics and Mechanics","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135838752","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Modelling Intermediate Species in Partially Premixed Turbulent Combustion Based on the LES-FGM Method 基于LES-FGM方法的部分预混湍流燃烧中间物质模拟

Applied Mathematics and Mechanics Pub Date : 2023-01-01 DOI: 10.21656/1000-0887.440068

ZHANG Weijie, WANG Jinhua, HU Guangya, LI Deli, WANG Ziqi, HUANG Zuohua

引用次数: 0

Analytical solution of wind-induced response of six-parameter practical viscoelastic damping energy dissipation structure based on Davenport wind speed spectrum 基于达文波特风速谱的六参数实用粘弹性阻尼耗能结构风致响应解析解

Applied Mathematics and Mechanics Pub Date : 2023-01-01 DOI: 10.21656/1000-0887.420211

Li Chuangdi, Liao Yuxiang, Yang Xuefeng, Ge Xinguang

引用次数: 0

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