Two-phase flow-induced vibration: fundamental studies

在热交换器和核燃料等工业部件中，过度的流动引起的振动会导致代价高昂的故障。例如，核蒸汽发生器的单管故障将导致车站关闭和维修费用约为2马币。如果使用精确的振动信息对部件进行振动优化，则可以实现更高的性能和更高的可靠性。这可以提高工业竞争力，仅在加拿大每年就可以节省100马币。2000年，在BWC/AECL/NSERC流体-结构相互作用工业研究主席的资助下，École理工学院启动了一项综合性研究项目，申请人为主席持有人。主席计划涵盖热交换器、核蒸汽发生器、管道系统和核燃料等组件；振动激励机制，如流体弹性不稳定性，周期和随机激励在轴向和横向流动。虽然主席计划的目标是工业的技术需求，但它提出了许多基本问题，这些问题非常适合在发现基金下进行调查。虽然超过一半的工艺组件在两相流中运行，但我们在这一领域的知识仍然非常有限。因此，本提案的目的是研究两相流中振动激励和阻尼机制的基本方面。基础研究主要集中在以下几个方面：1)内两相流作用下挠性管的流弹性失稳；2)两相流的周期激振力；3)两相流减振。

Excessive flow-induced vibration can lead to very costly failures in industrial components such as heat exchangers and nuclear fuels.  For example a single tube failure in a nuclear steam generator would lead to a station shutdown and repairs costing some M$2.  Higher performance and improved reliability can be achieved if components are optimised for vibration with accurate vibration information.  This can lead to improved industrial competitiveness and savings in the order of M$100 per year in Canada alone. A comprehensive research program was initiated in 2000 at École Polytechnique under the BWC/AECL/NSERC Industrial Research Chair of Fluid-Structure Interaction of which the applicant is the Chair Holder. The Chair program covers components such as heat exchangers, nuclear steam generators, piping systems and nuclear fuels; vibration excitation mechanisms such as fluidelastic instability, periodic and random excitation in both axial and cross flow. While the Chair program is aimed at the technology needs of industry it raises many fundamental questions that are very appropriate for investigation under a Discovery Grant. While more than half of process components operate in two-phase flow our knowledge in this area is still very limited.  Thus, the objective of this proposal is to study fundamental aspects of vibration excitation and damping mechanisms in two-phase flows. Fundamental studies are proposed in the following areas: 1) Fluidelastic instability of flexible tubes subjected to internal two-phase flow; 2) Periodic vibration excitation forces in two-phase flows; 3) Vibration damping in two-phase flows.