航空发动机可拆卸盘鼓型转子安全运行保障方法研究

The dismountable disk-and-drum rotor of the aero-engine refers to the rotor combined by the pull rods with compressed wheel discs at different levels. Since the rotor with the special structure is no longer a continuous holistic rotor, the degree and the distribution of the pre-tightening force affect the vibration performance of the dismountable disk-and-drum rotor, leading to the occurrence of the looseness fault. At the same time, there is an irreconcilable contradiction between the airborne sensors and the information completeness requirement for fault diagnosis. The vibration signals emerge with non-stationary, nonlinear, high noise and weak fault characteristic, etc. Therefore, aiming at the characteristic and the difficulty of the dismountable disk-and-drum rotor for aero-engine, the vibration characteristic and fault mechanism is studied. The vibration characteristic and the pull rod looseness fault mechanism influenced by the pre-tightening force of the pull rod is revealed. The multiwavelets are studied. The multiwavelets basis function matching with the fault waveform characteristic is constructed. The signal decomposition and reconstruction algorithm of the multiwavelets is proposed. The Clifford support vector machines (Clifford SVM) are proposed. The Clifford kernel function is constructed. The Clifford SVM mapping model is constructed to map signal characteristic with fault pattern, so as to realize the fault pattern recognition..The project is expected to make breakthrough in the research of the security assurance technology . The research achievement has important practical significance in ensuring the safe operation of the aero-engine and extending the service life.

航空发动机可拆卸盘鼓型转子是指通过拉杆螺栓将各级轮盘压紧组合的转子。由于不是一个连续的整体，轮盘周向的拉杆螺栓预紧力程度及分布影响其振动特性，容易发生拉杆螺栓松动故障。同时，机载传感器与故障诊断信息完备性需求之间存在不可调和的矛盾，振动信号具有非平稳、非线性、强噪声、故障特征微弱等特点。所以本项目针对航空发动机可拆卸盘鼓型转子的特点和难点，研究振动特性与故障机理，揭示拉杆螺栓预紧力对振动特性及松动故障的影响机理。研究多小波信号分析方法，构造与可拆卸盘鼓型转子故障特征波形相匹配的多小波基函数，提出多小波的信号分解与重构算法。研究Clifford支持向量机，构造Clifford核函数，建立振动信号特征与故障模式的Clifford支持向量机映射模型，实现故障模式识别。. 本项目有望在航空安全保障技术研究上取得重要进展，研究成果将为确保航空发动机安全运行、延长使用寿命等具有重要意义。

航空发动机可拆卸盘鼓型转子是指通过拉杆螺栓将各级轮盘压紧组合的转子。由于不是一个连续的整体，轮盘周向的拉杆螺栓预紧力程度及分布影响其振动特性，容易发生拉杆螺栓松动、轮盘破裂等故障。同时，机载传感器与故障诊断信息完备性需求之间存在不可调和的矛盾，振动信号具有非平稳、非线性、强噪声、故障特征微弱等特点。所以本项目针对航空发动机可拆卸盘鼓型转子的特点和难点，研究了振动特性与故障机理，揭示拉杆螺栓预紧力对振动特性及松动故障的影响机理。分别研究了基于DB小波、提升小波包、GHM多小波的拉杆螺栓激振响应信号分析方法，定义了拉杆螺栓装配紧度熵这一定量识别指标。研究了Clifford支持向量机及其核函数，建立了信号特征与故障模式的Clifford支持向量机映射模型，实现故障模式识别。本项目在航空安全保障技术研究上取得重要进展，研究成果将为确保航空发动机安全运行、延长使用寿命等具有重要意义。