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Modelling and analysis of metal flowing behaviors in constraining ring rolling of tapered ring with thin wall and three high ribs

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Chinese Journal of Aeronautics 2023年第6期36卷 476-492页

作者： Lin HUA Duanyang TIAN xinghui han Wuhao ZHUANG Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070China Hubei Longzhong Laboratory Xiangyang 441000China School of Automotive Engineering Wuhan University of TechnologyWuhan 430070China

Tapered ring with thin wall and three high ribs(TRTWTHR),showing complicated geometry(wall thickness is less than 4 mm and rib height exceeds 20 mm),is extensively utilized to fabricate the critical structural parts of aerospace equipment such as spacecraft cabin,rocket body and fuel tank because of light weight and high carrying *** to fabricate TRTWTHR with high performance is a critical problem that aerospace area needs to *** this work,constraining ring rolling(CRR)technique is first adopted to form *** metal streamlines(UMS)and uncoordinated growth of three ribs easily occur in CRR of TRTWTHR,which makes the forming quality of TRTWTHR difficult to be *** with this difficulty,an analytical model that can predict UMS and the height of three ribs in CRR of TRTWTHR is established so as to guide the process design of ***,the reliability of the established analytical model and the feasibility of CRR of TRTWTHR are confirmed by FE simulation and ***,using the established analytical model,the window of UMS occurring relevant to the tapered angle of TRTWTHR and the location of the rib of middle end is ***,three uncoordinated growth modes among three ribs are found when the width of three ribs is identical and UMS do not occur,and the mechanisms of three uncoordinated growth modes are revealed.

关键词： Analytical model Constraining ring rolling Growth of three ribs Metal streamlines Tapered ring with thin wall and three high ribs

An innovative constraining ring rolling process for manufacturing conical rings with thin sterna and high ribs

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Chinese Journal of Aeronautics 2022年第8期35卷 324-339页

作者： Duanyang TIAN xinghui han Lin HUA Xuan HU Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070 China School of Automotive Engineering Wuhan University of TechnologyWuhan 430070China

Conical rings with thin sterna and high ribs(CRTSHR)are key bearing-load parts of aerospace equipment,which are required to be manufactured with high performance and *** ring rolling is the most preferred method for manufacturing high-performance ring parts,but it can hardly achieve the forming of CRTSHR due to the extreme geometry of *** solve this difficulty,an innovative constraining ring rolling process(CRR)is proposed in this paper to manufacture *** evaluate the proposed CRR and reveal its deformation behaviors,a thermomechanical coupled FE model for CRR of CRTSHR is ***,the experiment for CRR of CRTSHR is performed on a modified ring rolling machine,which proves that CRR of CRTSHR is feasible and the established FE model is *** on the reliable FE model,the metal flow mode in deformed CRTSHR is analyzed,and the deformation characteristics such as the stress state,strain distribution and the evolution of power parameters in CRR of CRTSHR are ***,the influences of key parameters such as the friction factor between ring and molds,the diameter of idle roll and the feed velocity of idle roll on CRR of CRTSHR are investigated by FE simulation.

关键词： Conical rings with thin sterna and high ribs Deformation characteristics FE simulation Metal flow Ring rolling

Radial envelope forming mechanism and process design method for cylindrical rings with thin wall and high web ribs

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Chinese Journal of Aeronautics 2023年第12期36卷 461-476页

作者： xinghui han Yanlei MIN Wuhao ZHUANG Lin HUA Duanyang TIAN Zushen DENG Ningbo LIU Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070China Hubei Longzhong LaboratoryXiangyang 441000China

Cylindrical rings with thin wall and high web ribs(CRTWHWR)are widely used as the key load bearing structures such as rocket body and space station cabin in aerospace ***,it is still difficult to efficiently manufacture CRTWHWR with high performance because of their extreme geometry with thin-walled skins,high web ribs and large *** this paper,a novel radial envelope forming process is put forward to efficiently achieve the plastic forming of CRTWHWR with high ***,the principle of radial envelope forming process is ***,an efficient design method for the tool motion and geometry is proposed based on the reverse envelope principle,i.e.,CRTWHWR is adopted to reversely envelope the tool and thus the tool which does not interfere with CRTWHWR can be efficiently obtained in a single ***,a reasonable 3D FE model of the radial envelope forming process of CRTWHWR is established and the radial envelope forming mechanism of CRTWHWR is comprehensively *** the FE simulation and experiments with material of plastic mud,a typical CRTWHWR with diameter of 300 mm,axial height of 192 mm,the maximum rib height of 25 mm,the minimum rib thickness of 3 mm and skin thickness of 5 mm is radial envelope formed,i.e.,the ratio of the maximum rib height to the minimum rib thickness reaches 8.33,the ratio of the maximum rib height to skin thickness reaches 5 and the ratio of diameter to the minimum rib thickness reaches *** above results verify that the proposed radial envelope forming process has great potentials in efficiently manufacturing CRTWHWR with extreme geometry.

关键词： Radial envelope forming Cylindrical ring with thin wall and high web ribs Forming mechanism FE simulation Tool design

玄地滋阴合剂治疗中枢性性早熟阴虚火旺证女童199例前瞻性队列研究

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中医杂志 2024年第16期65卷 1673-1680页

作者：王文沁林雅婷袁琳和婧伟韩兴绘汪永红俞建严卫丽孙雯复旦大学附属儿科医院上海市闵行区201102

目的观察玄地滋阴合剂治疗女童中枢性性早熟(CPP)阴虚火旺证的临床疗效和安全性,并分析身体质量指数(BMI)对疗效的影响。方法纳入236例CPP阴虚火旺证女童,均给予玄地滋阴合剂口服治疗,每次30 ml,每天2次,共治疗6个月。治疗前后检测患儿... 详细信息

目的观察玄地滋阴合剂治疗女童中枢性性早熟(CPP)阴虚火旺证的临床疗效和安全性,并分析身体质量指数(BMI)对疗效的影响。方法纳入236例CPP阴虚火旺证女童,均给予玄地滋阴合剂口服治疗,每次30 ml,每天2次,共治疗6个月。治疗前后检测患儿体重、身高、骨龄,计算BMI和BMI标准化值(BMI Z值)、骨龄与实际年龄差值;B超检测子宫卵巢大小,计算子宫容积(V子宫)、双侧卵巢容积(V左卵巢,V右卵巢)、双侧最大卵泡直径(r左卵泡及r右卵泡);检测血清性激素水平,包括促卵泡激素(FSH)、促黄体生成素(LH)、泌乳素(PRL)、雌二醇(E2)、睾酮(T),并进行中医证候评分。采用多元线性回归分析骨龄与实际年龄差值、子宫容积变化的影响因素。患儿根据基线BMI分为正常体重组及超重/肥胖组两组,比较两组患儿治疗前后骨龄、骨龄与实际年龄差值、V子宫及BMI Z值。结果最终199例患儿进入统计分析,与治疗前比较,治疗后患儿骨龄、BMI及BMI Z值增大,骨龄与实际年龄差值、中医证候积分、V子宫、V左卵巢、V右卵巢、r左卵泡、r右卵泡减小,血清FSH、LH、E2、T水平下降(P0.05)。结论玄地滋阴合剂治疗CPP阴虚火旺证女童可降低患儿骨龄、性激素水平,减小卵巢和子宫体积,改善临床症状,对超重/肥胖儿童效果亦佳,对CPP女童骨龄的抑制作用不受BMI影响,且安全性好。

关键词：中枢性性早熟女童阴虚火旺证玄地滋阴合剂肥胖骨龄性激素身体质量指数

Influence of Alignment Errors on Contact Pressure during Straight Bevel Gear Meshing Process

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Chinese Journal of Mechanical Engineering 2015年第6期28卷 1089-1099页

作者： han xinghui HUA Lin DENG Song LUO Qiuping Hubei Key Laboratory of Advanced Technology for Automotive Components School of Automotive EngineeringWuhan University of Technology

Straight bevel gears are widely applied in automotive, aerospace, chemical and many other fields as one of the most common type of gears. Currently, the researches on straight bevel gears have focused on the fields of fatigue, wear, noise and vibration, while little attention is paid to the effect of multiple alignment errors on the gear tooth wear. To study the influence of alignment errors on the gear tooth wear, a simulated model of a straight bevel gear pair is established. Then, the contact pressure on the tooth surface is analyzed under the various alignment errors according to the Archard wear relationship. The main combinations of alignment errors played vital roles on the tooth wear are investigated. The result shows that under the single alignment error, the contact pressure moves to the tooth heel and increases greatly at here when ？P=0.1 or ？G=0.1; when ？E=–0.03, the contact pressure greatly increases at the tooth heel, but it obviously increases at the tooth toe when ？E=0.03; the alignment error ？γ=1 has little effect on the contact pressure on the tooth surface. Moreover, the combination of ？P, ？G, ？E〈0 and ？γ is the most dangerous type among the multiple alignment errors. This research provides valuable guidelines for predicting the tooth wear under various alignment errors.

关键词： straight bevel gear multiple alignment errors contact pressure wear

Subsurface crack propagation under rolling contact fatigue in bearing ring

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Science China(Technological Sciences) 2013年第10期56卷 2422-2432页

作者： DENG Song han xinghui QIN XunPeng HUANG Song School of Automotive Engineering Hubei Key Laboratory of Advanced Technology of Automotive Parts Wuhan University of Technology

The influences of subsurface cracks,distributing along the axial direction,on the rolling contact fatigue(RCF)faliure in a bearing ring are investigated.A realistic three-dimensional model of the bearing ring containing three subsurface cracks is used to evaluate the fatigue crack propagation based on stress intensity factor(SIF)***,the distributions of the subsurface cracks along the axial direction are varied to study their effects on *** results provide valuable guidelines for enhanced understanding of RCF in bearings.

关键词： bearing ring subsurface cracks rolling contact fatigue stress intensity factors

Effectiveness of ZiYin Xiehuo granules and Zishen Qinggan granules on partial precocious puberty in girls: a multicenter, randomized, single-blind, controlled trial

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Journal of Traditional Chinese Medicine 2018年第5期38卷 740-745页

作者： Sun Wen han xinghui Wang Yonghong Yu Jian Yan Weili Zhao Jun Chen Weibin Xue Zheng Traditional Chinese Medicine Department Children's Hospital of Fudan University Teaching and Research Section of Clinical Epidemiology Children's Hospital of Fudan University Department of Pediatrics Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine Department of Pediatrics YueYang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine Department of Pediatrics Shanghai Hospital of Traditional Chinese Medicine

OBJECTIVE: To evaluate the effect of ZiYin Xiehuo granules(ZYXH) and Zishen Qinggan granules(ZSQG) on partial precocious puberty(PPP).METHODS: This was a multicenter, randomized, single-blind, positive-controlled trial. A total of 143 pa-tients were assigned to either the ZYXH group or the ZSQG group using a random number table. The ZYXH group received ZYXH three times daily for 6 months and the ZSQG group received ZSQG three times daily for 6 months. Mammary nucleus diameter; the results of uterus, ovarian, and maximum follicle measures; and Chinese medicine symptom pattern scores were compared at baseline and after 3 months and 6 months of ***: After 3 months' treatment, there were no significant differences between the two groups in mammary nucleus index changes(left 3.4 ± 3.1 vs3.5 ± 3.1, P = 0.790; right 3.0 ± 2.9 vs 3.6 ± 3.0, P =0.719). The uterine volume in the ZYXH group was smaller than that in the ZSQG group(2.1 ± 1.6 vs2.6 ± 2.2, P = 0.006). There were no significant between-group differences in ovarian volume and maximum follicular diameter on either side(ovarian volume: left 1.2 ± 0.7 vs 1.3 ± 0.6, P = 0.8; right1.2 ± 0.7 vs 1.4 ± 1.1, P = 0.984; maximum follicular diameter: left 3.9 ± 1.7 vs 3.5 ± 2.2, P = 0.158; right3.5 ± 1.7 vs 3.9 ± 2.1, P = 0.314).CONCLUSION: ZYXH granules and ZSQG granules both affected the size of the mammary nucleus in girls with PPP, and improved Chinese medicine symptom patterns. ZYXH granules showed slight advantages over ZSQG granules in terms of the decrease in the size of the uterus, ovaries, and ovarian follicles.

关键词： ZiYin Xiehuo granules Partial precocious puberty Multicenter,Randomized controlled trial

面向航空航天的薄壁锥形筒件轧制成形过程几何状态综合控制方法

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中国机械工程 2023年第23期34卷 2873-2880页

作者：谢涵汪小凯韩星会华林张科郑戈飞武汉理工大学现代汽车零部件技术湖北省重点实验室武汉430070 武汉理工大学汽车零部件技术湖北省协同创新中心武汉430070 武汉理工大学材料绿色精密成形技术与装备湖北省工程中心武汉430070

针对航空航天薄壁锥形筒件轧制过程几何变形状态难以控制的问题,研究了薄壁锥形筒件轴线偏移、轴线倾斜、小端拉缩三种典型异常变形状态及形成机理,提出了基于筒件线速度反馈的锥辊运动协调控制方法,建立了锥形筒件轧制过程锥辊运动控... 详细信息

针对航空航天薄壁锥形筒件轧制过程几何变形状态难以控制的问题,研究了薄壁锥形筒件轴线偏移、轴线倾斜、小端拉缩三种典型异常变形状态及形成机理,提出了基于筒件线速度反馈的锥辊运动协调控制方法,建立了锥形筒件轧制过程锥辊运动控制模型;提出了薄壁锥形筒件坯料优化设计方法,并建立了相应的芯辊倾斜进给控制策略,保证了锥形筒件直径长大速度的一致性,消除了因金属轴向和周向流动不匹配导致的小端拉缩现象;基于ABAQUS软件和VUAMP子程序开发,建立了集成所提控制方法和策略的薄壁锥形筒件轧制有限元模型。对比分析了常规规划控制、上述方法独立控制和综合控制下的筒件轧制成形效果,结果表明,综合控制方法下的轴线偏移量、圆度误差、同心度误差和倾斜角误差等指标相比于常规规划控制在整圆阶段内分别降低了93.6%、75.3%、95.1%、97.2%。

关键词：薄壁锥形筒件轧制成形变形状态控制方法

超大型环件径轴向轧制过程偏移机理及自适应模糊控制方法研究

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中国机械工程 2023年第1期34卷 109-117页

作者：张科汪小凯华林韩星会宁湘锦武汉理工大学现代汽车零部件技术湖北省重点实验室武汉430070 武汉理工大学汽车零部件技术湖北省协同创新中心武汉430070 武汉理工大学材料绿色精密成形技术与装备湖北省工程中心武汉430070

超大型环件径轴向轧制过程容易产生偏移,影响环件轧制稳定性和成形质量。为研究环件偏移机理及其控制方法,分析了轴向孔型滑移区中前滑区和后滑区的分布变化规律,建立了理想情况下不产生环件偏移时锥辊旋转运动学条件,获得了滑移区的最... 详细信息

超大型环件径轴向轧制过程容易产生偏移,影响环件轧制稳定性和成形质量。为研究环件偏移机理及其控制方法,分析了轴向孔型滑移区中前滑区和后滑区的分布变化规律,建立了理想情况下不产生环件偏移时锥辊旋转运动学条件,获得了滑移区的最优速度匹配系数。此外,从历史轧制数据中归纳人工控制经验后提出了基于锥辊转速自适应模糊调节的环心偏移量控制方法,基于ABAQUS软件和VUAMP子程序开发,建立了集成有环心偏移量模糊控制算法的∅10 m超大型环件径轴向轧制有限元模型,研究了采用最优速度匹配系数的常规控制和自适应模糊控制下的环心偏移量变化规律。结果表明,自适应模糊控制下的平均环心偏移量相比于常规控制降低了72.4%,仿真结果和试验数据均验证了所提超大型环件轧制过程偏移自适应模糊控制方法的有效性。

关键词：超大型环件径轴向轧制偏移自适应模糊控制有限元仿真