检索结果-南通市图书馆

Leakage Model of axial clearance and Test of Scroll Compressors

Journal of Shanghai Jiaotong university(Science) 2020年第4期25卷 531-537页

作者：王建吉刘涛 School of Mechanical and Electrical Engineering Lanzhou University of TechnologyLanzhou 730050China Mechanical and Electronic Engineering Department Long Dong UniversityQingyang 745000GansuChina

Leakage clearance plays an important role in guaranteeing high efficiency of scroll *** view of the shortcomings of the existing leakage models of axial clearance of scroll compressors,a modified Fano flow model and a turbulence model are presented based on the flow characteristics of fluid in the leakage passage under actual working ***,according to the Fano flow energy equation and the turbulence theory,two kinds of leakage models,Fano flow model and turbulence model,of axial clearance are ***,the established models are verified through an experimental platform established to measure the axial clearance leakage in the working process of a scroll compressor,and the measured values are compared with the values obtained from the two theoretical ***,the effect of such factors as pressure difference,clearance amount,spindle speed on the axial clearance leakage is *** show that the two established models can precisely reflect the variation law of axial clearance leakage of scroll compressor under different working *** particular,the Fano flow model is more suitable for predicting the clearance leakage when the spindle speed is low(less than 3500 r/min)and the clearance is small(less than 0.025 mm),whereas the turbulence model is suitable for high spindle speed(more than 3500 r/min)and large clearance(more than 0.025 mm).

关键词： scroll compressor axial clearance leakage model mass flow rate

来源：

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

Three-dimensional parametric contact analysis of planetary roller screw mechanism and its application in grouping for selective assembly

引用

Frontiers of Mechanical Engineering 2024年第1期19卷 53-72页

作者： Huilin HE Peitang WEI Huaiju LIU Xuesong DU Rui HU Genshen LIU Yajun WU State Key Laboratory of Mechanical Transmission for Advanced Equipment Chongqing UniversityChongqing 400044China Taiyuan Heavy Machinery Group Co. Ltd.Taiyuan 030024China

The planetary roller screw mechanism(PRSM)is a novel precision transmission mechanism that realizes the conversion between linear and rotary *** contact characteristics of helical surfaces directly determine PRSM’s performance in load-carrying capacity and transmission ***,studying the contact characteristics of PRSM forms the fundamental basis for enhancing its transmission *** this study,a three-dimensional parametric analysis method of contact characteristics is proposed based on the PRSM meshing principle and PyVista(a high-level API to the Visualization Toolkit).The proposed method considers the influence of machining errors among various thread *** effects of key machining errors on contact positions and axial clearance,as well as their sensitivities,are *** excellent solution accuracy,this method exhibits higher calculation efficiency and stronger robustness than the analytical and numerical meshing *** influence of nominal diameter and pitch errors of the screw,roller,and nut on the axial clearance follows a linear relationship,whereas flank angle errors have negligible effects on the axial *** corresponding influence coefficients for these three machining errors on the axial clearance are 0.623,0.341,and *** variations in contact positions caused by individual errors are *** angle errors and roller diameter errors result in linear displacements of the contact points,whereas pitch errors cause the contact points to move along the arc of the roller *** on the proposed threedimensional parametric contact characteristics analysis method,the Fuzzy C-Means clustering algorithm considering error sensitivity is utilized to establish a component grouping technique in the selective assembly of critical PRSM components,ensuring the rational and consistent clearances based on the given component’s machining *** study provides effective guidance for analyzing conta

关键词： planetary roller screw mechanism(PRSM) contact position axial clearance machining error grouping for selective assembly

来源：

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

An Error Equivalent Model of Revolute Joints with clearances for Antenna Pointing Mechanisms

引用

Chinese Journal of Mechanical Engineering 2018年第2期31卷 97-105页

作者： Quan Liu Sheng-Nan Lu Xi-Lun Ding School of Mechanical Engineering and Automation Beihang University

Joint clearances in antenna pointing mechanisms lead to uncertainty in function deviation. Current studies mainly focus on radial clearance of revolute joints, while axial clearance has rarely been taken into consideration. In fact, own?ing to errors from machining and assembly, thermal deformation and so forth, practically, axial clearance is inevitable in the joint. In this study, an error equivalent model(EEM) of revolute joints is proposed with considering both radial and axial clearances. Compared to the planar model of revolute joints only considering radial clearance, the journal motion inside the bearing is more abundant and matches the reality better in the EEM. The model is also extended for analyzing the error distribution of a spatial dual?axis("X–Y" type) antenna pointing mechanism of Spot?beam antennas which especially demand a high pointing accuracy. Three case studies are performed which illustrates the internal relation between radial clearance and axial clearance. It is found that when the axial clearance is big enough, the physical journal can freely realize both translational motion and rotational motion. While if the axial clearance is limited, the motion of the physical journal will be restricted. Analysis results indicate that the consideration of both radial and axial clearances in the revolute joint describes the journal motion inside the bearing more precise. To further validate the proposed model, a model of the EEM is designed and fabricated. Some suggestions on the design of revolute joints are also provided.

关键词： Error modeling Joint clearances Antenna pointing mechanism Radial clearance axial clearance

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：