风机技术
風機技術
풍궤기술
COMPRESSOR,BLOWER & FAN TECHNOLOGY
2013年
5期
11-21
,共11页
王跃方%郭婷%孙兴华%沈鼓
王躍方%郭婷%孫興華%瀋鼓
왕약방%곽정%손흥화%침고
叶轮%气流激振%强度%疲劳%离心式压缩机
葉輪%氣流激振%彊度%疲勞%離心式壓縮機
협륜%기류격진%강도%피로%리심식압축궤
impellers%airflow induced vibration%stress%fatigue%centrifugal compressor
以往离心式压缩机的叶轮强度设计主要基于静力分析结果,忽略了非定常气动力引起的脉动应力。工程实际表明,许多叶轮的破坏并非静强度不足,而是材料的高周疲劳破坏。考虑离心式压缩机叶轮的非定常气流激振效应,给出了动应力计算和结果后处理过程中应注意的几个问题。气流激振下的动应力分析可以确定叶轮在气动荷载和机械荷载联合作用下的交变应力,为疲劳分析和可靠性设计打下基础。
以往離心式壓縮機的葉輪彊度設計主要基于靜力分析結果,忽略瞭非定常氣動力引起的脈動應力。工程實際錶明,許多葉輪的破壞併非靜彊度不足,而是材料的高週疲勞破壞。攷慮離心式壓縮機葉輪的非定常氣流激振效應,給齣瞭動應力計算和結果後處理過程中應註意的幾箇問題。氣流激振下的動應力分析可以確定葉輪在氣動荷載和機械荷載聯閤作用下的交變應力,為疲勞分析和可靠性設計打下基礎。
이왕리심식압축궤적협륜강도설계주요기우정력분석결과,홀략료비정상기동력인기적맥동응력。공정실제표명,허다협륜적파배병비정강도불족,이시재료적고주피로파배。고필리심식압축궤협륜적비정상기류격진효응,급출료동응력계산화결과후처리과정중응주의적궤개문제。기류격진하적동응력분석가이학정협륜재기동하재화궤계하재연합작용하적교변응력,위피로분석화가고성설계타하기출。
Previous stress-based designs of centrifugal compressor impellers were mostly based on static analysis without considering the fluctuating stress caused by unsteady aerodynamic pressures. However, many practical failures of impellers were found not because of lack of static strength but the high-cycle fatigue failures. In this paper, the effect of vibratory stress induced by unsteady airflows of centrifugal compressor impellers is investigated with emphasis on computation of dynamic stress and post processing of results. The analysis methodology for dynamic stress considering transient airflow effect can be applied to determine the alternative stress of impellers jointly excited by pneumatic and mechanical loadings and hence be able to serve as a foundation of fatigue analysis and reliability-based designs.