液控调节阀多场耦合及磨蚀失效行为研究

Coal liquefaction technology is a new direction in high efficiency and clean utilization of coal all over the world. Hydraulic control valve is one of key devices in coal liquefaction technology, because of its low anti-abrasion ability, short service life, which seriously restricts the stable operation of coal liquefaction technology. This project intends to focus on multi-field couping and abrasion behavior in hydraulic control valve, investigating fluid dynamic performance, abrasion failure characteristics, multiphase flow impact couping effect, and abrasion state monitoring of hydraulic control valve. An erosion-abrasion model of multiphase flow in hydraulic control valve will be established, the relationship between the wear rate and valve structure will also be analyzed. A method for descriping characterization of abrasion degree of multiphase flow field in hydraulic control valve will be presented, the behavior prediction system will also be presented. In addition, the model of multiphase flow impact will be proposed, and the abrasion position of hydraulic control valve will also be obtained. Furthermore, the detection method of multiphase flow based on fiber-optic sensors will also be introduced, wear failure predication of hydraulic control valve will be achieved. The expected results in this project will provide support for prolongate the lifetime of hydraulic control valve, improve the safety of the coal liquefaction technology, and also promote the localization process of hydraulic control valve of China.

煤液化技术是目前世界上煤碳高效清洁利用发展新方向。液控调节阀作为煤液化系统中的关键设备，因其抗磨蚀能力差、寿命短的问题严重制约了煤液化生产过程的稳定运行。本项目拟围绕液控调节阀气液固多场耦合及磨蚀失效这一关键科学问题，开展液控调节阀流场动态特性、磨蚀失效特征、冲击耦合机理和磨蚀状态监测等方面的研究。主要内容包括：建立液控调节阀空化流场中固体颗粒的冲击磨蚀模型，分析液控调节阀结构参数与磨损率分布的关系；提出液控调节阀多相流场中磨蚀程度表征方法，构建液控调节阀磨蚀失效行为评价体系；建立液控调节阀多相流冲击压力模型，准确预测液控调节阀易磨蚀失效区域；提出基于光纤传感器的液控调节阀磨蚀状态监测方法，开展液控调节阀磨蚀失效预测。研究成果可提高煤液化液控调节阀的服役寿命，增强调节阀的运行可靠性，为实现液控调节阀的国产化提供技术支持。

针对煤液化调节阀运行工况苛刻、抗磨蚀能力差、服役寿命短的问题，提出了调节阀流场中空化区域识别特征参量，准确获取了调节阀内空化轴向和径向产生位置、分布区域以及形态的变化，为调节阀受空蚀破坏的位置和寿命预测奠定了基础；获取了流场中固体颗粒的分布特性和沿空化区域的扩散特性，阐明了液控调节阀空化流场中固体颗粒对节流部位的冲击磨蚀机理，指出适当减小阀芯头部圆弧半径、调节阀阀座下游流道长度、增加阀座扩展角可以有效抑制空化现象，提高了煤液化系统中液控调节阀的服役寿命；建立了煤液化调节阀的稳态液动力模型，基于熵产理论阐明了调节阀内流动总熵产与稳态液动力近似为指数关系，提出了一种阀芯振动信号采集系统并揭示了调节阀阀芯轴向和径向的振动特性，提高了煤液化调节阀的安全性和可靠性；建立了液控调节阀空化流动多物理场同步测量系统，揭示了调节阀内非定常空化流动形态和壁面压力脉动之间的关系，形成了一种基于遗传算法优化的自支持向量机调节阀空化状态识别技术，实现了调节阀健康状态的实时在线诊断。本项目的研究成果为提高煤液化液控调节阀的服役寿命、增强调节阀的运行可靠性提供了理论基础。