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Chinese Journal of Aeronautics 2022年第11期35卷 264-276页

作者： Shaojing DONG Yufan FANG Wentong HU xiuli shen Gaoxiang CHEN School of Energyand Power Engineering Beihang UniversityBeijing 10083China Beijing Key Laboratory of Aero-Engine Structure and Strength Beihang UniversityBejing 100083China Jiangxi Research Institute Beihang UniversityNanchang 330096China Navigation and Control Technology Research Institute of China Ordnance Industries Beijing 100089China Research Institute of Aero-engine Beihang UniversityBeijing 100083China

In aero engine design, determining whether the preliminary design will have disruptive effects on the detailed design is the key to multidisciplinary design optimization in the preliminary design stage. In order to adapt to the non-orthogonal parameter value range caused by the selfconstrained parametric modeling method, a non-orthogonal space mapping method that maps the optimal Latin hypercube sampling points of the traditional orthogonal design space to the non-orthogonal design space is proposed. Based on the logical regression method in machine learning field, a kind of feasible domain boundary identification method is employed to identify whether the sample spatial response meets the relevant criteria. The method proposed in this paper is used to identify and analyze the key technologies of the high-pressure turbine mortise joint structure. It is found that the preliminary design of the aero engine may lead to the failure to obtain a mortise joint structure meeting the design requirements in the detailed design stage. The mortise joint structure needs to be pre-optimized in the preliminary design stage.

关键词： Aero engine Disruptive design Flow pass multidisciplinary optimization Pre-identification Preliminary design phase

Macro-phenomenological high-strain-rate elastic fracture model for ice-impact simulations

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Chinese Journal of Aeronautics 2023年第3期36卷 146-160页

作者： Jiang FAN Qinghao YUAN Fulei JING Guangchen BAI xiuli shen School of Energy and Power Engineering Beihang UniversityBeijing 100191China Beijing Key Laboratory of Aero-Engine Structure and Strength Beijing 100191China Collaborative Innovation Center of Advanced Aero-Engine Beijing 100191China Aero-Engine Academy of China Aero Engine(Group)Corporation of ChinaBeijing 101304China

The ice impact can cause a severe damage to an aircraft’s exposed structure,thus,requiring its prevention.The numerical simulation represents an effective method to overcome this challenge.The establishment of the ice material model is critical.However,ice is not a common structural material and exhibits an extremely complex material behavior.The material models of ice reported so far are not able to accurately simulate the ice behavior at high strain rates.This study proposes a novel high-precision macro-phenomenological elastic fracture model based on the brittle behavior of ice at high strain rates.The developed model has been compared with five reported models by using the smoothed particle hydrodynamics method so as to simulate the ice-impact process with respect to the impact speeds and ice shapes.The important metrics and phenomena(impact force history,deformation and fragmentation of the ice projectile and deflection of the target)were compared with the experimental data reported in the literature.The findings obtained from the developed model are observed to be most consistent with the experimental data,which demonstrates that the model represents the basic physics and phenomena governing the ice impact at high strain rates.The developed model includes a relatively fewer number of material parameters.Further,the used parameters have a clear physical meaning and can be directly obtained through experiments.Moreover,no adjustment of any material parameter is needed,and the consumption duration is also acceptable.These advantages indicate that the developed model is suitable for simulating the iceimpact process and can be applied for the anti-ice impact design in aviation.

关键词： Crack propagation Elastic fracture High strain rate Ice impact Impact force Material model

Integration of nanoindentation and finite element method for interpretable tensile properties:A crossscale calculation method of uneven joints

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Chinese Journal of Aeronautics 2023年第6期36卷 233-248页

作者： Kun GAO Zhiying LIU xiuli shen Lizhong LANG Shaojing DONG School of Energy and Power Engineering Beihang UniversityBeijing100191China Department of Materials Science and Engineering University of TorontoTorontoON M5S 3E4Canada

Nanoindentation testing and its Reverse Analysis Method(RAM)show great potential in understanding the tensile properties of metallic alloys with various microstructures.Nevertheless,the tensile properties of heterogeneous materials such as nickel-based superalloy welded joints have not been well interpreted by combining the microstructures and nanoindentation results,due to their diverse and complex microscopic zones,which throws shade on the properties of separated zones in the material.Here we demonstrated a new method of implanting nanoindentation results into Finite Element Method(FEM)and applied the method to the welded joints with the zones of various microstructure features.The local properties are calculated by the nanoindentation data using RAM,and used as input of Finite Element(FE)simulation of an identical indentation process,to in turn verify the accuracy and reliability of the reverse model.The simulation results reveal that the global mechanical behaviors,such as Young's modulus,yield strength and strain hardening exponent,are related to the local properties to a great extent.Thus,the global properties can be verified by simulation straight after experiments,taking consideration of local properties and dimension parameters of different zones.It is shown that the maximum error between calculation of RAM and testing is within 5.1%in different zones,and the errors of maximum indentation depth and residual depth obtained by FE simulation are less than 2.4%,which indicates that the method provides a reliable prediction of mechanical properties of superalloy welded joints.

关键词： Finite element method Nanoindentation Reverse analysis method Tensile properties Welded joints

Multi-scale thermodynamic analysis method for 2D SiC/SiC composite turbine guide vanes

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Chinese Journal of Aeronautics 2018年第1期31卷 117-125页

作者： Xin LIU xiuli shen Longdong GONG Peng LI School of Energy and Power Engineering Beihang University Beijing 100083 China Navigation and Control Technology Research Institute of China Ordnance Industries Beijing 100089 China

Ceramic Matrix Composite （CMC） turbine guide vanes possess multi-scale stress and strain with inhomogeneity at the microscopic scale. Given that the macroscopic distribution cannot reflect the microscopic stress fluctuation, the macroscopic method fails to meet the requirements of stress and strain analysis of CMC turbine guide vanes. Furthermore, the complete thermodynamic properties of 2D woven SiC/SiC-CMC cannot be obtained through experimentation, Accordingly, a method to calculate the thermodynamic properties of CMC and analyze multi-scale stress and strain of the turbine guide vanes should be established. In this study, the multi-scale thermodynamic analysis is investigated. The thermodynamic properties of Chemical Vapor Infiltration （CVI） pro- cessed SiC/SiC-CMC are predicted by a Representative Volume Element （RVE） model with porosity, leading to the result that the relative error between the calculated in-plane tensile modulus and the experimental value is 4.2%. The macroscopic response of a guide vane under given conditions is predicted. The relative error between the predicted strain on the trailing edge and the experimental value is 9.7%. The calculation of the stress distribution of micro-scale RVE shows that the maximum value of microscopic stress, which is located in the interlayer matrix, is more than 1.5 times that of macroscopic stress in the same direction and the microscopic stress distribution of the interlayer matrix is related to the pore distribution of the composite.

关键词： Ceramic matrix composites Multi-scale Representative volume element Thermal-mechanical coupling Turbine guide vane

Structural design and optimization for vent holes of an industrial turbine sealing disk

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Chinese Journal of Aeronautics 2021年第5期34卷 265-277页

作者： Cheng YAN Jianfeng ZHU xiuli shen Jun FAN Zhigang JIA Tiefeng CHEN School of Aerospace Engineering Xiamen UniversityXiamen 361005China School of Energy and Power Engineering Beihang UniversityBeijing 100083China Army Aviation Institute Beijing 100000China Aero Engine Academy of China Beijing 101300China AECC Commercial Aircraft Engine Co LtdShanghai 200241China

Severe stress concentration occurs around circular vent holes of an industrial turbine sealing disk.This paper investigates the structural design and optimization for the vent holes to effectively reduce the maximum von Mises stress and improve the fatigue life of the turbine sealing disk.An efficient integrated design optimization method is presented based on a novel non-circular vent hole design method in combination with a variable dimension sub-model method,a self-developed modeling and meshing tool,and the Multi-Island Genetic Algorithm.The proposed non-circular vent hole is biaxial symmetric and consists of four smoothly connected arcs.The variable dimension sub-model method is utilized to obtain accurate results in the fields around the vent holes within the computationally acceptable time.The modeling and meshing tool is developed by using the Tcl/Tk Scripts to rebuild the geometry and generate the high-quality hexahedral mesh automatically.The Multi-Island Genetic Algorithm is adopted to solve the studied constrained optimization problem.After optimization,the maximum von Mises stress is reduced from 1305.644 MPa to 963.435 MPa,and the fatigue life is increased from 3091 cycles to 30,297 cycles.The results show that the proposed design and optimization methods can significantly improve the performance of the turbine sealing disk along with the remarkable drop in stress concentration.

关键词： Multi Island Genetic Algorithm Stress concentration Structural optimization Sub-model method Vent hole

红景天苷调节FAK/MEK/ERK信号通路对HPV阳性宫颈癌细胞发生发展的影响

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中国病原生物学杂志 2024年第2期19卷 166-171页

作者：张要盛任晓沈玲杨秀丽河南省南阳医学高等专科学校第一附属医院肿瘤内科三病区河南南阳473000

目的探讨红景天苷(Sal)调节局部黏着斑激酶(FAK)/胞外信号调节激酶的激酶(MEK)/细胞外信号调节激酶(ERK)信号通路对人乳头瘤病毒(HPV)阳性宫颈癌细胞发生发展的影响。方法分别用0、2.5、5、10、20、40、80、160、320μg/mL Sal处理HPV1... 详细信息

目的探讨红景天苷(Sal)调节局部黏着斑激酶(FAK)/胞外信号调节激酶的激酶(MEK)/细胞外信号调节激酶(ERK)信号通路对人乳头瘤病毒(HPV)阳性宫颈癌细胞发生发展的影响。方法分别用0、2.5、5、10、20、40、80、160、320μg/mL Sal处理HPV18阳性人宫颈癌细胞HeLa,根据细胞存活率确定适宜的Sal浓度用于正式实验。将HeLa细胞分组为对照组、Sal低剂量组、Sal中剂量组、Sal高剂量组、表皮细胞生长因子(EGF)(FAK激活剂)组、Sal高剂量+EGF组,CCK-8法、5-乙炔基-2′-脱氧尿苷(EdU)染色检测细胞增殖;Transwell检测细胞迁移与侵袭;qRT-PCR检测HeLa细胞中增殖细胞核抗原(PCNA)、转移侵袭增强因子1(MIEN1)、基质金属蛋白酶9(MMP-9)mRNA表达;Western Blot检测细胞中人乳头瘤病毒18型(HPV18)E6、HPV18 E7、p-FAK、p-MEK、p-ERK1/2蛋白表达。结果选取Sal浓度为40、80、160μg/mL用于正式实验。与对照组比较,Sal低剂量组、Sal中剂量组、Sal高剂量组HeLa细胞A_(450)值、EdU阳性细胞率、细胞迁移及侵袭数目、PCNA、MIEN1、MMP-9 mRNA表达及HPV18 E6、HPV18 E7、p-FAK、p-MEK、p-ERK1/2蛋白表达降低,且呈剂量依赖性(P<0.05);与对照组比较,EGF组HeLa细胞A_(450)值、EdU阳性细胞率、细胞迁移及侵袭数目、PCNA、MIEN1、MMP-9 mRNA表达及HPV18 E6、HPV18 E7、p-FAK、p-MEK、p-ERK1/2蛋白表达升高(P<0.05);与Sal高剂量组比较,Sal高剂量+EGF组HeLa细胞A_(450)值、EdU阳性细胞率、细胞迁移及侵袭数目、PCNA、MIEN1、MMP-9 mRNA表达及HPV18 E6、HPV18 E7、p-FAK、p-MEK、p-ERK1/2蛋白表达升高(P<0.05)。结论Sal可能通过抑制FAK/MEK/ERK信号通路抑制HPV阳性宫颈癌细胞发生发展。

关键词：红景天苷局部黏着斑激酶/胞外信号调节激酶的激酶/细胞外信号调节激酶信号通路人乳头瘤病毒宫颈癌增殖侵袭

Investigation on experimental load spectrum for high and low cycle combined fatigue test

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Propulsion and Power Research 2013年第4期2卷 235-242页

作者： Rongqiao Wang Jiaming Wei Dianyin Hu xiuli shen Jiang Fan School of Energy and Power Engineering Beihang UniversityBeijing 100191China

As the outfield load spectrum is so complicated that it cannot be used directly for test study in laboratory.This paper presents a method to determine load spectrum for high and low cycle combined fatigue of turbine mortise at elevated temperature through experimental and numerical method.First of all,the low cycle load spectrum with duration time is determined through cumulative damage rule.The rain flow counting method is applied to obtain main cycles and sub cycles,and then the stress cycle is converted into pulsation cycle(stress ratio=0)based on the S-N curve and the Goodman curve;Secondly,three groups of different amplitudes tests are established to determine the high cycle amplitude.Finally,another three groups of the high-low combined cycle fatigue(HLCCF)tests for turbine mortise of a certain type engine are carried out.The results show that the macro and micro failure modes are identical with outfield's,which verifies the accuracy of the conversion method.

关键词： High-low combined cycle fatigue Load spectrum Turbine mortise Rain flow counting method Fracture analysis

基于声发射技术的T800碳纤维复合材料拉伸失效机制分析

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固体火箭技术 2024年第3期47卷 411-420页

作者：董少静李凯丁文辉王立强申秀丽北京航空航天大学能源与动力工程学院北京100191 航天动力技术研究院西安710025 西安航天动力技术研究所西安710025

为揭示固体火箭发动机碳纤维缠绕复合材料壳体多载荷工况下的失效机理,开展了单向T800碳纤维复合材料试件不同偏轴角度下的拉伸实验。利用声发射(AE)无损测试技术获得了试件完整波形信号,结合Pearson相关系数选取了AE信号的特征参数,通... 详细信息

为揭示固体火箭发动机碳纤维缠绕复合材料壳体多载荷工况下的失效机理,开展了单向T800碳纤维复合材料试件不同偏轴角度下的拉伸实验。利用声发射(AE)无损测试技术获得了试件完整波形信号,结合Pearson相关系数选取了AE信号的特征参数,通过K-means聚类算法对AE信号进行了聚类分析,同时结合扫描电镜(SEM)拍摄的微观断口形貌将不同的损伤机制与声发射聚类组对应。进一步利用代表性体积单元并结合渐进损伤方法,实现了单向复合材料损伤过程的数值模拟。分析结果表明,AE信号的峰值频率与幅值两类参数的相关系数低于0.2。采用二者对AE信号进行聚类分析,同时结合数值仿真获得的应力-应变曲线,发现纤维断裂峰值频率最高,基体开裂峰值频率居中,界面脱粘峰值频率最低,试件宏观破坏时的AE信号幅值最高。

关键词：碳纤维复合材料固体火箭发动机纤维缠绕壳体声发射偏轴拉伸聚类分析渐进损伤

基于儿童友好理念的城市公园设计研究——以承德南山公园为例

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工业设计 2024年第1期 76-79页

作者：屈秀丽沈海泳沈阳建筑大学设计艺术学院沈阳110000

目前很多城市公园缺少儿童友好理念的植入,在设计规划上更多的是从成人的视角出发,导致真正适合儿童休闲娱乐的空间较少,影响儿童的身心发展。文章以儿童友好理念为切入点,并通过实地调研探究城市公园存在的问题和公园延续发展的设计思... 详细信息

目前很多城市公园缺少儿童友好理念的植入,在设计规划上更多的是从成人的视角出发,导致真正适合儿童休闲娱乐的空间较少,影响儿童的身心发展。文章以儿童友好理念为切入点,并通过实地调研探究城市公园存在的问题和公园延续发展的设计思路,总结儿童友好城市公园设计的原则。城市公园在设计过程中应充分考虑儿童的心理、生理及行为特征,以期为城市公园进一步改善儿童发展环境、优化儿童公共服务、加强儿童权利保障、拓宽儿童成长空间提供基础和保障,建设出儿童所需的真正友好的城市公园。

关键词：儿童友好理念城市公园公园设计设计规划

小肠黏膜下层处理的间充质干细胞片促进伤口愈合

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山东大学学报（医学版） 2024年第4期62卷 68-77,84页

作者：沈飞飞李栋刘玲红鞠秀丽山东大学齐鲁医院儿科山东济南250012

目的探讨细胞外基质(extracellular matrix,ECM),尤其是小肠黏膜下层(small intestinal submucosa,SIS)处理后的脐带间充质干细胞(umbilical cord mesenchymal stem cells,UC-MSCs)细胞片对伤口愈合的影响。方法使用组织块贴壁法从脐带组织中分离、培养原代UC-MSCs。化学脱核法制备脱细胞SIS,通过物理粘附方式将重组人纤维连接蛋白(recombinant human fibronectin,rFN)、SIS和基质胶(Matrigel)固定在聚苯乙烯(polystyrene,PS)细胞培养皿表面。分析PS表面、rFN-PS表面、SIS-PS表面以及Matrigel-PS表面对UC-MSCs形态的影响,RT-PCR法检测基因表达的变化,使用纳米颗粒追踪分析检测细胞外囊泡(extracellular vesicles,EVs)分泌情况的改变。分别用无ECM处理的、rFN处理的、SIS处理的以及Matrigel处理的UC-MSCs细胞片治疗大鼠皮肤全层切除创面,通过计算伤口面积占原始伤口面积的比值进一步验证治疗效果。结果与PS表面相比,SIS-PS表面培养的UC-MSCs形态未受影响(P>0.05);RT-PCR检测结果显示,SIS-PS表面培养的UC-MSCs中NANOG同源框(nanog homeobox,NANOG,P=0.041)、SRY-Box转录因子-2(SRY-box transcription factor 2,SOX-2,P=0.009)、八聚体结合转录因子-4(octamer-binding transcription factor-4,OCT-4,P<0.001)、白介素-10(interleukin-10,IL-10,P=0.049)、吲哚胺2,3-双加氧酶(indoleamine 2,3-dioxygenase,IDO,P=0.007)和转化生长因子-β(transforming growth factor beta,TGF-β,P=0.046)基因表达增强,而且分泌EVs的能力显著提高(P<0.001)。动物实验结果可见,使用SIS处理的UC-MSCs细胞片治疗组对伤口愈合的促进作用最为显著,第7天伤口占原始伤口面积的比值最低为26.9%±6.1%。结论SIS-PS表面培养的UC-MSCs显著提高了免疫抑制和囊泡分泌能力,由此制成的细胞冻干片具有更强的促进伤口愈合的能力。

关键词：间充质干细胞小肠黏膜下层伤口愈合细胞外囊泡胞外基质