CAJ | 학술논문

高速列车表面压力测试过程中，压阻式绝压传感器受列车振动冲击激扰，引起传感器输出干扰；同时，车体振动又会引起表面压力变化，导致有用信号与干扰信号难于准确分离。针对现有的经验模态分解（EMD）降噪过程中存在端点效应和模态混叠现象，提出了一种改进的集合经验模态分解（IEEMD），并利用仿真信号进行验证。模型车在单自由度方向振动激励下，运用 IEEMD 方法对车体表面压力信号进行经验模态分解，再计算各固有模态函数（IMFs）分量自相关函数与原始信号自相关函数的相关性系数，提取振动引起的压力。同时利用 CFD 计算模型车在同一激励下振动压力，从而分离出振动干扰，并建立振动与振动干扰的回归关系，为准确提取列车表面压力提供理论指导。
고속열차표면압력측시과정중，압조식절압전감기수열차진동충격격우，인기전감기수출간우；동시，차체진동우회인기표면압력변화，도치유용신호여간우신호난우준학분리。침대현유적경험모태분해（EMD）강조과정중존재단점효응화모태혼첩현상，제출료일충개진적집합경험모태분해（IEEMD），병이용방진신호진행험증。모형차재단자유도방향진동격려하，운용 IEEMD 방법대차체표면압력신호진행경험모태분해，재계산각고유모태함수（IMFs）분량자상관함수여원시신호자상관함수적상관성계수，제취진동인기적압력。동시이용 CFD 계산모형차재동일격려하진동압력，종이분리출진동간우，병건립진동여진동간우적회귀관계，위준학제취열차표면압력제공이론지도。
Piezoresistive pressure sensors are affected by shock and vibration when measuring surface pressure of a high-speed train,sensors'output interference is caused.Simultaneously,the train body's vibration causes the change of its surface pressure to lead to useful signals being difficult to separate from interferences.Aiming at the phenomena of end effects and mode mixing in process of noise reduction of the empirical mode decomposition (EMD),an improved ensemble empirical mode decomposition (IEEMD)method was put forward and it was verified with simulated signals.The model-train was excited with a single DOF vibration excitation.The train surface pressure signal was decomposed with IEEMD,and the correlation coefficients between the intrinsic mode function (IMF)autocorrelation functions and the original signal autocorrelation function were calculated.Then,the pressure caused by vibration was tracted.At the same time,the vibration pressure of the model-train surface was calculated with CFD under the same excitation,through comparing these presure data the vibration interference could be separated.The regression relationship between vibration and vibration interference was built to provide a theoretical guidance for extracting surface pressure accurately.