楊光 任尊松 孫守光
摘要: 輪對(duì)彈性變形和旋轉(zhuǎn)振動(dòng)對(duì)輪軌系統(tǒng)運(yùn)行安全性影響需要從理論上進(jìn)行深入研究。利用ANSYS有限元分析軟件對(duì)輪對(duì)彈性化處理后,在SIMPACK多體動(dòng)力學(xué)軟件中建立了包含高速旋轉(zhuǎn)彈性體輪對(duì)的車輛系統(tǒng)動(dòng)力學(xué)模型。采用數(shù)值方法,得到了輪軸彈性彎曲變形量以及不同軌道不平順激擾下輪對(duì)垂向振動(dòng)加速度響應(yīng)等。結(jié)果表明,考慮彈性和旋轉(zhuǎn)振動(dòng)后,輪對(duì)車軸發(fā)生彎曲變形效應(yīng)明顯且中部變形量最大,車輛運(yùn)行速度對(duì)車軸彎曲變形量和輪軌附加動(dòng)力有一定的影響,輪對(duì)垂向振動(dòng)加速度頻譜出現(xiàn)與旋轉(zhuǎn)速度相關(guān)的頻率特征。本文方法和結(jié)果對(duì)揭示輪對(duì)真實(shí)運(yùn)動(dòng)特征和研究高速輪軌安全性具有良好的指導(dǎo)意義。關(guān)鍵詞: 彈性輪對(duì); 高速列車; 旋轉(zhuǎn); 頻率特征
中圖分類號(hào): U260.331+.1文獻(xiàn)標(biāo)志碼: A文章編號(hào): 10044523(2016)04071406
DOI:10.16385/j.cnki.issn.10044523.2016.04.019
引言
近年來,中國(guó)穩(wěn)步發(fā)展高速鐵路,高速動(dòng)車組運(yùn)營(yíng)速度已到達(dá)300 km/h。作為列車走行的關(guān)鍵部件,高速旋轉(zhuǎn)輪對(duì)運(yùn)用安全性受到了高度關(guān)注與重視,亟需在高速范圍內(nèi),對(duì)旋轉(zhuǎn)輪對(duì)發(fā)生彈性變形后引起的輪軌接觸、走行關(guān)系、輪軌附加動(dòng)力以及車輛系統(tǒng)振動(dòng)和運(yùn)行安全性等問題開展深入研究。傳統(tǒng)車輛動(dòng)力學(xué)研究工作中,輪對(duì)一般考慮為剛體或者輪對(duì)僅向前做平移運(yùn)動(dòng),無法體現(xiàn)出輪對(duì)高速旋轉(zhuǎn)過程中的彈性變形及其對(duì)結(jié)構(gòu)振動(dòng)的影響。近年來,國(guó)內(nèi)外關(guān)于輪對(duì)彈性化后車輛系統(tǒng)振動(dòng)特性的研究逐漸增多。萬鵬等[1]分別將輪對(duì)考慮為剛性和彈性建立整車模型,得到了輪對(duì)彈性化處理以后車輛臨界速度較剛性輪對(duì)的值有所降低的結(jié)論;張永貴[2]研究發(fā)現(xiàn),在針對(duì)輪軸振動(dòng)特性的分析中,采用彈性輪對(duì)比采用剛性輪對(duì)時(shí)得到的計(jì)算更加準(zhǔn)確,也更符合實(shí)際情況;馬衛(wèi)華等[3]通過加大輪軸彎曲剛度來改善輪對(duì)的垂向振動(dòng)和輪軌垂向力,以實(shí)現(xiàn)改善輪軌動(dòng)態(tài)接觸狀態(tài)的目的;張寶安[4]提出彈性輪對(duì)的結(jié)構(gòu)振動(dòng)對(duì)輪軌接觸點(diǎn)位置,蠕滑率蠕滑力和脫軌因數(shù)等均產(chǎn)生較明顯的影響;劉韋等[5]研究表明,輪對(duì)考慮為彈性體將會(huì)更加準(zhǔn)確地反映出車輪多邊形化對(duì)輪軌力的影響;Baeza L等[6]對(duì)比分析彈性旋轉(zhuǎn)輪對(duì)模型和剛性輪對(duì)模型在車輪扁疤,軌道不平順激擾下的輪軌力差異。但是,在既有研究中,對(duì)于輪對(duì)彈性化處理以后,車軸彈性彎曲變形對(duì)高速旋轉(zhuǎn)輪對(duì)自身振動(dòng)特性方面的研究尚未涉及。
有鑒于此,本文以某型高速動(dòng)車組為對(duì)象,研究彈性輪軸彎曲變形特征,并進(jìn)一步分析彎曲變形對(duì)高速旋轉(zhuǎn)輪對(duì)振動(dòng)特性的影響。為避免彈性構(gòu)架[7]和彈性車體[89]對(duì)輪對(duì)垂向加速度頻率成分的影響,這里僅將輪對(duì)處理為彈性體,建立剛彈耦合車輛系統(tǒng)動(dòng)力學(xué)模型。
Abstract: Further theoretical studies are needed about the influences of elastic deformation and rotation vibration of wheelset on the wheelrail system operation safety. The railway vehicle system with the highspeed rotating wheelsets which were considered as elastic bodies with the FEM is established in the SIMPACK software. With the numerical method, the degree of bending deformation of the axle is achieved while the wheelset was considered as the elastic body, and the vertical vibration acceleration response of the wheelset under different rail irregularity excitation is also obtained in this paper. The results show that, while considering the elastic and rotation vibration, the axle bending deformation effects are obvious, and the maximum deformation occurs in the center. The degree of bending deformation and the additional force of wheel rail are affected by the vehicle operation speed. The frequency characteristic associated with the speed of rotation appears in the spectrum of vertical acceleration of the wheelset. The methods and the results in this paper have guiding significance to the real characteristics of the wheelset rotation and the studies on the highspeed wheel rail safety.
Key words: elastic wheelset; highspeed train; rotation; frequency characteristics