检索结果-南通市图书馆

Journal of Thermal Science 2024年第5期33卷 1867-1882页

作者： liU Tantao GAO limin li ruiyu School of Power and Energy Northwestern Polytechnical UniversityXi'an 710012China School of Aerospace Engineering Xi'an Jiaotong UniversityXi'an 710049China

For complex flows in compressors containing flow separations and adverse pressure gradients,the numerical simulation results based on Reynolds-averaged Navier-Stokes(RANS)models often deviate from experimental measurements more or *** improve the prediction accuracy and reduce the difference between the RANS prediction results and experimental measurements,an experimental data-driven flow field prediction method based on deep learning and l_(1)regularization is proposed and applied to a compressor cascade flow *** inlet boundary conditions and turbulence model parameters are calibrated to obtain the high-fidelity flow *** Saplart-Allmaras and SST turbulence models are used independently for mutual *** contributions of key modified parameters are also analyzed via sensitivity *** results show that the prediction error can be reduced by nearly 70%based on the proposed *** flow fields predicted by the two calibrated turbulence models are almost the same and nearly independent of the turbulence *** corrections of the inlet boundary conditions reduce the error in the first half of the *** turbulence model calibrations fix the overprediction of flow separation on the suction surface near the tail edge.

关键词： experimental data-driven compressor cascade deep learning l_(1)regularization

The difference of the ionomer–catalyst interfaces for poly(aryl piperidinium)hydroxide exchange membrane fuel cells and proton exchange membrane fuel cells

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第7期17卷 6102-6110页

作者： Xuerui liu Xingdong Wang Chanyu Zhang Yun Cai Bowen Chen Dongyue Xin Xiaoxiao Jin Wei Zhu Klaus Wippermann Hui li ruiyu li Zhongbin Zhuang Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China State Key Lab of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China Research Institute of Petroleum Processing SINOPECBeijing 100083China DeepHytec Co. Ltd.Shenzhen 518118China Institute of Energy and Climate Research(IEK-14) Forschungszentrum Jülich GmbHJülich 52425Germany Beijing Key Laboratory of Energy Environmental Catalysis Beijing University of Chemical TechnologyBeijing 100029China

The microstructures of the ionomer–catalyst interfaces in the catalyst layers are important for the fuel cell performance because they determine the distribution of the active triple-phase ***,we investigate the ionomer–catalyst interactions in hydroxide exchange membrane fuel cells(HEMFCs)using poly(aryl piperidinium)and compare them with proton exchange membrane fuel cells(PEMFCs).It is found that different catalyst layer microstructures are between the two types of fuel *** ionomer/carbon(I/C)ratio does not have a remarkable impact on the HEMFC performance,while it has a strong impact on the PEMFC performance,indicating the weaker interaction between the HEMFC ionomer and *** dynamics simulations demonstrate that the HEMFC ionomer tends to distribute on the carbon support,unlike the PEMFC ionomer,which heavily covers the Pt *** results suggest that the poisoning effect of the ionomer on the catalyst is much weaker in HEMFCs,and the improved ionomer/catalyst interaction is beneficial for the HEMFC performances.

关键词： hydroxide exchange membrane fuel cells catalysts ionomer oxygen reduction reaction interfaces

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

基于正交试验的曳力模型改进研究

华中科技大学学报（自然科学版） 2024年第7期52卷 113-118页

作者：邓磊李瑞宇黄笑乐车得福西安交通大学动力工程多相流国家重点实验室陕西西安710049 广东省特种设备检测研究院顺德检测院广东佛山528300

通过正交试验法向经典曳力模型中添加颗粒拟温度项以改进曳力模型,并对比改进模型BVKM-1和BVKM-2与原始模型在鼓泡流化床算例中的表现.结果表明:正交试验法参数寻优可大幅减小工作量,适合CFD-DEM曳力模型改进研究.通过向曳力模型以多项... 详细信息

通过正交试验法向经典曳力模型中添加颗粒拟温度项以改进曳力模型,并对比改进模型BVKM-1和BVKM-2与原始模型在鼓泡流化床算例中的表现.结果表明:正交试验法参数寻优可大幅减小工作量,适合CFD-DEM曳力模型改进研究.通过向曳力模型以多项式形式添加颗粒拟温度项,改进模型的时均结果得到了显著改善.在y=35 mm截面x=1.01 mm处,BVKM-2模型与实验值的相对误差仅为14.03%,而原始BVK模型的相对误差高达93.73%.BVKM-2模型的表现优于BVKM-1,也更接近原始BVK模型.BVKM-1和BVKM-2形式类似,参数略有差别,但模拟结果差别较大,这说明向曳力模型以多项式形式添加颗粒拟温度项时,模拟结果对多项式的参数非常敏感.

关键词：鼓泡流化床曳力模型模型改进数值模拟正交试验法

在线全文

学校读者我要写书评

暂无评论

压气机叶片加工误差离散性控制研究进展综述

机械科学与技术 2024年第7期43卷 1101-1119页

作者：何智伟李瑞宇李湉罗明西北工业大学机电学院航空发动机高性能制造工业和信息化部重点实验室西安710072 西安交通大学航天航空学院西安710049 中国航发航空科技股份有限公司成都600503

航空发动机压气机整体叶盘通常设计为旋转周期对称结构。然而,实际加工中同一级整体叶盘上不同叶片之间以及单个叶片自身存在的加工误差离散性会对流场参数产生不利影响。因此,提高整体叶盘叶片加工误差一致性成为普遍关注的难题。综述... 详细信息

航空发动机压气机整体叶盘通常设计为旋转周期对称结构。然而,实际加工中同一级整体叶盘上不同叶片之间以及单个叶片自身存在的加工误差离散性会对流场参数产生不利影响。因此,提高整体叶盘叶片加工误差一致性成为普遍关注的难题。综述了近年来针对同级叶盘不同叶片加工误差离散性对气动性能影响规律的相关研究,以及加工过程强时变特性下误差离散度控制的相关成果。就误差离散性现象及产生原因、对性能影响规律及加工误差离散度控制方法这3个方面展开论述。最后展望了未来误差离散度加工控制方法发展趋势,为未来相关研究工作提供参考。

关键词：整体叶盘加工误差气动性能离散性离散度控制

在线全文

学校读者我要写书评

暂无评论

基于实测扭转度误差对叶片气动合格性探讨

工程热物理学报 2024年第3期45卷 707-714页

作者：但玥王浩浩高丽敏李瑞宇西北工业大学动力与能源学院西安710072 西北工业大学翼型、叶栅空气动力学国家级重点实验室西安710072

在叶片实际加工过程中,不可避免会产生扭转度超差叶片,为探究其气动合格性,以跨声速叶片Rotor37为研究对象,首先将加工公差[-0.5°,+0.5°]添加至设计叶片,采用数值模拟的方法确定气动性能合格范围,分析性能变化规律;而后基于实测扭转... 详细信息

在叶片实际加工过程中,不可避免会产生扭转度超差叶片,为探究其气动合格性,以跨声速叶片Rotor37为研究对象,首先将加工公差[-0.5°,+0.5°]添加至设计叶片,采用数值模拟的方法确定气动性能合格范围,分析性能变化规律;而后基于实测扭转度误差均值及标准差,创建加工合格以及超差叶片,总结其气动合格性。研究结果表明:受扭转度误差影响,叶片特性曲线整体偏移,因此在选择近失速及峰值效率工况参数衡量稳定裕度的前提下,“欠偏转”叶片稳定裕度减小,而“过偏转”叶片的增大;以加工公差为参考,叶片超差区域与未超差区域的通流面积和攻角变化趋势相反,即两区域对叶片性能的影响存在抵消作用,使得存在超差叶片气动合格的情况。

关键词：跨声速压气机叶片加工误差扭转度气动性能

Case Study on AI Robotics in Senior living in China

在线全文

学校读者我要写书评

暂无评论

Psychology Research 2024年第2期14卷 81-88页

作者： Xiajie Zhao ruiyu li Hanyang Univ. SeoulKorea

Currently,in China,as the elderly population rapidly increases due to the increase in aging,the importance of the elderly’s living environment and quality of life is ***,the development of technology presents the possibility of providing a better life to the *** study is conducted to investigate and analyze the current status and performance of artificial intelligence robot technology introduced in the elderly residential space in China,and contribute to the improvement of the living and convenience of the ***,we investigate the cases of various types of artificial intelligence robots currently being used in the residential environment for the elderly in ***,by evaluating the technical performance and function of each artificial intelligence robot,we will look at how it meets the needs of the elderly’s special bedfall,health care,and social ***,we analyze the impact of artificial intelligence robots on the daily life of the elderly and investigate users’experiences and effects to understand social ***,based on the obtained results,suggestions and future prospects for effectively introducing artificial intelligence robots into the residential environment for the elderly in China are *** this,it is expected to contribute to understanding how artificial intelligence robot technology is being applied in the residential environment of the elderly in China,and to find ways to improve the convenience and quality of life of the elderly.

关键词： aging population artificial intelligence(AI) residential space for the elderly

Experimental investigation on static/dynamic characteristics of a fast-response pressure sensitive paint

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2018年第6期31卷 1198-1205页

作者： ruiyu li limin GAO Tianlong ZHENG Guanhua YANG School of Power and Energy Northwestern Polytechnical University Xi'an 710072 China Collaborative Innovation Center of Advanced Aero-Engine Beijing 100083 China

An optical-based technique using Pressure-Sensitive Paint（PSP） is a promising method to measure the distribution of surface pressure on an aerodynamic model. The static and dynamic characteristics of a fast-response PSP that is developed in the Chinese Academy of Sciences（CAS）are analyzed and tested to serve as the basis for experiments on unsteady surface measurement using a fast-response PSP. Two calibration systems used for this study are set up to investigate the temperature dependency, response time, and resolution. A data processing method, used for dynamic data, is analyzed and selected carefully to determine the optimum signal. Results show that the fastresponse PSP can be used normally at temperatures from 25 ℃ to 80 ℃. The effect of temperature on the accuracy of the measurement must be considered when temperatures are beyond the temperature range of 30–40 ℃. The dynamic calibration device with a solenoid valve can achieve a pressure jump within a millisecond order. The resolution is determined by the signal-to-noise ratio of the photo-multiplier tube. Results of the measurement show that the response time of the PSP decreases with a large pressure variation, and the response time is below 0.016 s when the pressure variation is under 40 kPa.

关键词： Dynamic calibration Pressure measurement Pressure sensitive paint Signal processing Unsteady flow

Application of shear-sensitive liquid crystal coating to visualization of transition and reattachment in compressor cascade

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2018年第11期31卷 2073-2079页

作者： ruiyu li limin GAO Shuai ZHANG Yongzeng li Tianyu GAO School of Power and Energy Northwestern Polytechnical UniversityXi'an 710072China Collaborative Innovation Center of Advanced Aero-Engine Beijing 100191China Aero-Engine Flight Test Chinese Flight Test EstablishmentXi'an 710089China

The present paper aims at introducing Shear-Sensitive liquid Crystal Coating(SSLCC)technology into compressor cascade measurement for the first time and serves as a basis for better understanding of the influence from the boundary layers. Optical path layout, which is the most significant difficulty in internal flow field measurement, will be solved in this paper by selfdesigned image acquisition device. Massive experiments with different Mach number and incidence are conducted at a continuous subsonic cascade wind tunnel to capture the boundary layer phenomenon. Image processing methods, such as Three-Dimensional(3-D) reconstruction and Hue conversion, are used to improve the accuracy for transition position detection. The analysis of the color-images indicates that complex flow phenomena including transition, flow separation,and reattachment are captured successfully, and the effect of Mach number and incidence on the boundary layer flow is also discussed. The results show that: the Mach number has a significant effect on transition position; the incidence has little effect on transition position, but it has a great impact on the transition distance and leading-edge separation; influenced by the end-walls, the reattachment occurs in advance under positive angle of attack conditions.

关键词： Compressor cascade Flow visualization Leading edge separation Shear-sensitive liquid crystal coating Transition

Experimental Investigation of a linear Cascade with Large Solidity Using Pressure Sensitive Paint and Dual-Camera System

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2021年第2期30卷 682-695页

作者： GAO limin YANG Guanhua GAO Tianyu li ruiyu HU Xiaoquan School of Power and Energy Northwestern Polytechnical UniversityXi'an 710129China The National Key Laboratory of Aerodynamic Design and Research Xi'an 710129China

Pressure Sensitive Paint(PSP)technique has been increasingly applied to the experimental research of aerodynamics and thermodynamics due to its strengths of non-contact,high resolution results and large coverage area,***,rarely has this technique been successfully used to the study of internal flow such as compressor cascade,since narrow flow passages would heavily restrict the acquisition of PSP *** this paper,PSP technique was used to study the pressure distribution on a linear compressor cascade with large solidity of 2.3,where the view of recording camera can be heavily blocked due to adjacent blade *** help get integrated PSP images of the internal flow passage,dual camera system along with image processing tools like 3D reconstruction and image integration were *** results showed that with the aid of such assistance,image results with good quality and readability could be ***,pressure data given by PSP were compared with data from traditional way of pressure taps and showed good *** results of the entire cascade passage surface were given with different inlet Mach numbers and incidence *** results showed that PSP technique can integrally measure cascade tunnel of large solidity with the help of dual-camera system.

关键词： pressure sensitive paint compressor cascade dual-camera system large solidity full channel measurement

Influence of leading edge with real manufacturing error on aerodynamic performance of high subsonic compressor cascades

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2021年第6期34卷 220-232页

作者： Chi MA limin GAO Haohao WANG ruiyu li Baohai WU School of Power and Energy Northwestern Polytechnical UniversityXi’an 710129China The National Key Laboratory of Aerodynamic Design and Research Xi'an 710129China Key Laboratory of Contemporary Design and Integrated Manufacturing Technology of Ministry of Education Northwestern Polytechnical UniversityXi'an 710072China

To investigate the influence of real leading-edge manufacturing error on aerodynamic performance of high subsonic compressor blades,a family of leading-edge manufacturing error data were obtained from measured compressor *** the limited samples,the leadingedge angle and leading-edge radius distribution forms were evaluated by Shapiro-Wilk test and quantile–quantile *** statistical characteristics provided can be introduced to later related *** parameterization design method B-spline and Bezier are adopted to create geometry models with manufacturing error based on leading-edge angle and leading-edge *** influence of real manufacturing error is quantified and analyzed by self-developed non-intrusive polynomial chaos and Sobol’*** mechanism of leading-edge manufacturing error on aerodynamic performance is *** results show that the total pressure loss coefficient is sensitive to the leading-edge manufacturing error compared with the static pressure ratio,especially at high ***,manufacturing error of the leading edge will influence the local flow acceleration and subsequently cause fluctuation of the downstream *** aerodynamic performance is sensitive to the manufacturing error of leading-edge radius at the design and negative incidences,while it is sensitive to the manufacturing error of leading-edge angle under the operation conditions with high incidences.

关键词： Aerodynamic performance Compressor cascade limited measurement data Manufacturing error Uncertainty analysis