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Influence of Methane-Hydrogen Mixture Characteristics on Compressor Vibrations

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Fluid Dynamics & Materials Processing 2024年第5期20卷 1031-1043页

作者： Vladimir Ya.Modorskii Ivan E.Cherepanov High Performance Computing Center Perm National Research Polytechnic UniversityPerm614990Russia

A transition to clean hydrogen energy will not be possible until the issues related to its production, transportation,storage, etc., are adequately resolved. Currently, however, it is possible to use methane-hydrogen *** gas can be transported using a pipeline system with the required pressure being maintained by gascompression stations. This method, however, is affected by some problems too. Compressors emergency stopscan be induced by vibrations because in some cases, mechanical methods are not able to reduce the vibrationamplitude. As an example, it is known that a gas-dynamic flow effect in labyrinth seals can lead to increasedvibrations. This paper presents the numerical simulation of rotor oscillations taking into account a gas-dynamicload. The influence of a transported mixture on the oscillatory process is investigated. Mixtures consisting ofmethane and hydrogen in various proportions and an air mixture are considered. The results are discussed forvarious operating pressures and include the rotor motion trajectories and oscillation frequency spectra obtainednumerically. It is shown that the gas mixture composition has a significant effect on the oscillations and theiroccurrence. Hydrogen as a working fluid reduces the vibration amplitude. Operating a compressor with hydrogenleads to a decrease in the resonant frequency, bringing it closer to the operating one. However, the operatingpressure at which maximum oscillations are observed depends slightly on the gas mixture composition.

关键词： Seal stabilities vibration fsi CFD multiphase flows hydrogen

Predicting Coronary Plaque Morphology Changes Based on Multimodality fsi Models Using Follow-Up IVUS and OCT Data

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医用生物力学 2019年第A1期34卷 93-94页

作者： Xiaoya Guo Don PGiddens David Molony Habib Samady Chun Yang Jie Zheng Mitsuaki Matsumura Gary SMintz Akiko Maehara Liang Wang Dalin Tang Department of Mathematics Southeast UniversityNanjing210096China The Wallace H.Coulter Department of Biomedical Engineering Georgia Institute of TechnologyAtlantaGA30332USA Department of Medicine EmoryUniversitySchool of MedicineAtlantaGA30307USA Mathematical Sciences Department Worcester PolytechnicInstituteWorcesterMA01609USA Mallinckrodt Institute of Radiology Washington UniversitySt.LouisMO63110USA The Cardiovascular Research Foundation Columbia UniversityNew YorkNY10022USA School of BiologicalScience and Medical Engineering Southeast UniversityNanjing210096China

Background Current bottleneck of patient-specific coronary plaque model construction is the resolution of in vivo medical *** threshold of cap thickness of vulnerable coronary plaques is 65 microns,while the resolution of in vivo coronary intravascular ultrasound(IVUS)images is 150-200 microns,which is not enough to identify vulnerable plaques with thin caps and construct accurate biomechanical plaque *** coherence tomography(OCT)with a 15-20μm resolution has the capacity to identify thin fibrous *** and OCT images could complement each other and provide for more accurate plaque morphology,especially,fibrous cap thickness measurements.A modeling approach combining IVUS and OCT was introduced in our previous publication for cap thickness quantification and more accurate cap stress/strain *** this paper,patient baseline and follow-up IVUS and OCT data were acquired and multimodality image-based Fluidstructure interaction(fsi)models combining 3D IVUS,OCT,angiography were constructed to better quantify human coronary atherosclerotic plaque morphology and plaque stress/strain conditions and investigate the relationship of plaque vulnerability and morphological and mechanical *** Baseline and 10-Month follow-up in vivo IVUS and OCT coronary plaque data were acquired from one patient with informed consent ***-registration and segmentation of baseline and follow-up IVUS and OCT images were performed for modeling *** and follow-up 3D fsi models based on IVUS and OCT were constructed to simulate the mechanical factors which integrating plaque morphology were employed to predict plaque *** 3D models were solved by ADINA(ADINA R&D,Watertown,MA,USA).The quantitative indices of cap thickness,lipid percentage were classified according to histological literatures and denoted as Cap Index and Lipid *** Index,Lipid Index and Morphological Plaque Vulnerability Index(MPVI)were chosen to quantify plaq

关键词： coronary plaque OCT IVUS vulnerability patient-specific fsi model

Analysis of the Flow Field and Impact Force in High-Pressure Water Descaling

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Fluid Dynamics & Materials Processing 2024年第1期20卷 165-177页

作者： Yue Cui Liyuan Wang Jian Wu Haisheng Liu Di Wu Key Lab of Intelligent Equipment Digital Design and Process Simulation Hebei ProvinceTangshan UniversityTangshan063000China Department of Intelligent Manufacturing Tangshan Vocational College of Science and TechnologyTangshan063001China

This study aims to improve the performances of the high-pressure water descaling technology used in steel hot rolling *** particular,a 2050 mm hot rolling line is considered,and the problem is investigated by means of a fluid–structure interaction(fsi)method by which the descaling effect produced by rolling coils with different section sizes is *** a flat fan-shaped nozzle at the entrance of the R1R2 roughing mill,the outflow field characteristics and the velocity distribution curve on the strike line(at a target distance of 30–120 mm)are *** is found that the velocity in the center region of the water jet with different target distances is higher than that in the boundary *** the target distance increases,the velocity of the water jet in the central region *** comparison with experimental results,it is shown that the simulation model can accurately predict the impact position of the high-pressure water on the impact plate,thereby providing a computational scheme that can be used to optimize the nozzle space layout and improve the slabs’descent effect for different rolling specifications.

关键词： High pressure water descaling flow field analysis fsi target distance strike range

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考虑fsi效应的核岛结构楼层反应谱研究

山东建筑大学学报 2022年第6期37卷 18-26页

作者：宋辰宁段志宁翟玉强胡令辉山东建筑大学土木工程学院山东济南250101 山东建筑大学建筑结构加固改造与地下空间工程教育部重点实验室山东济南250101 济南市农业综合行政执法支队山东济南250101

地震荷载作用下,核岛结构的楼层反应谱是核电厂厂房内管道、设备等地震安全评价的重要输入,楼层反应谱的研究对设备抗震分析具有重要的意义。文章以新型压水堆核电厂核岛结构为研究对象,基于有限元软件开展安全停堆地震动作用下核岛结... 详细信息

地震荷载作用下,核岛结构的楼层反应谱是核电厂厂房内管道、设备等地震安全评价的重要输入,楼层反应谱的研究对设备抗震分析具有重要的意义。文章以新型压水堆核电厂核岛结构为研究对象,基于有限元软件开展安全停堆地震动作用下核岛结构数值模拟分析,探讨在考虑和不考虑流固耦合(Fluid-structure Interaction,fsi)效应两种情况下楼层反应谱的差异,并研究了考虑fsi效应时核岛结构楼层反应谱及反应谱峰值随结构高度的变化规律,分析不同阻尼比对楼层反应谱的影响。结果表明:考虑fsi效应使结构的主频降低,楼层反应谱峰值向长周期段移动;辅助厂房的约束作用导致屏蔽厂房下部参考点水平方向加速度反应谱表现出高频特性;随着核岛结构高度的增大,各楼层反应谱峰值整体呈现增大的趋势,辅助厂房的约束作用导致相应参考点加速度反应谱峰值较小;阻尼比大小影响加速度反应谱的峰值,但不改变反应谱的频谱特性。

关键词：核岛结构楼层反应谱 fsi 阻尼比

基于可调谐激光器扫频干涉（fsi）绝对距离测量方法研究进展

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红外与激光工程 2021年

作者：宋鲁明张福民孙栋林洪沂黄晓桦于淼张乾厦门理工学院光电与通信工程学院天津大学精密测试技术及仪器国家重点实验室福建省光电技术与器件重点实验室

绝对距离测量的精度对于航空航天科技、精密装备加工、卫星编队、行星空间定位等领域具有重要意义。近年来，基于可调谐激光器的扫频干涉（fsi）测距技术以其突破2π模糊度，无测量死区，不接触且不依赖导轨等优点成为国际研究热点。本... 详细信息

绝对距离测量的精度对于航空航天科技、精密装备加工、卫星编队、行星空间定位等领域具有重要意义。近年来，基于可调谐激光器的扫频干涉（fsi）测距技术以其突破2π模糊度，无测量死区，不接触且不依赖导轨等优点成为国际研究热点。本文在阐述fsi测距原理的基础上，简要分析了测距系统中部分器件的类型与性能，如可调谐激光器、探测器等，以及影响测距系统不确定度的因素，包括非线性扫频、多普勒频移、色散失配等方面，着重介绍了国内外对影响不确定度因素的相应补偿方法，并对补偿后的测量结果进行对比与总结。

关键词： fsi 非线性扫频多普勒频移色散失配不确定度

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基于fsi的中国金融安全实证分析

金融论坛 2007年第10期12卷 14-18页

作者：沈悦谢勇田嫄西安交通大学经济与金融学院金融系西北大学经济管理学院

随着我国加入WTO后金融自由化进程不断加快,建立金融安全预警机制,及时掌握金融安全动态,对防止金融危机的爆发至关重要。本文首先在相关文献研究的基础上,依据"三性原则"筛选出能够反映我国金融安全运行状况的20个指标,其次参照国际标... 详细信息

随着我国加入WTO后金融自由化进程不断加快,建立金融安全预警机制,及时掌握金融安全动态,对防止金融危机的爆发至关重要。本文首先在相关文献研究的基础上,依据"三性原则"筛选出能够反映我国金融安全运行状况的20个指标,其次参照国际标准和中国具体实际确定了临界值或区间值,最后经计算得出反映我国金融安全程度的指数——fsi(Financial Security Index),并运用fsi对我国1992～2005年间的金融安全状况进行了评判。通过研究得出结论认为:1992～2005年我国的金融安全总体趋势是逐渐变好,加入WTO虽然并未使我国的金融安全状况变差,但是在目前金融业逐渐开放的条件下仍然需要高度关注金融风险。

关键词：金融自由化金融安全 fsi 亚洲金融危机

Audi R8 5.2 fsi Quattro

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汽车工程学报 2011年第1期 78-79页

第四届fsi中国资本市场论坛(2000年度)综述

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经济理论与经济管理 2000年第2期20卷 77-79页

作者：经济理论与经济管理编辑部经济理论与经济管理杂志社

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财务报表保险(fsi)制度研究综述

保险研究 2009年第7期 106-111页

作者：张冬王伟西南财经大学会计学院四川成都610074

财务报表保险(fsi)制度对于会计和保险界来说是一个全新的研究领域,已有研究发现,fsi与SOA2002相比更能有效解决审计师独立性问题,从而提升投保公司的会计信息质量。随之而来的好处是公司治理的改善及资源配置的优化,这对现实经济具有... 详细信息

财务报表保险(fsi)制度对于会计和保险界来说是一个全新的研究领域,已有研究发现,fsi与SOA2002相比更能有效解决审计师独立性问题,从而提升投保公司的会计信息质量。随之而来的好处是公司治理的改善及资源配置的优化,这对现实经济具有重大意义。本文在论述fsi制度产生背景的基础上,详细综述了国内外理论研究者关于fsi制度的已有研究,最后作出总结并给出了未来研究之方向。

关键词： fsi SOA2002 审计独立性公司治理资源配置