起伏式振动状态下气-液两相流型及流动特性参数检测研究

As an important component of the nuclear-powered submarine nuclear reactor, and gas-liquid two phase flow are the main parts of it. The nuclear-powered submarine will produce fluctuant vibration when it march in different sea conditions, which will increase the complexity and variability of gas-liquid two phase flow conditions, then the high-precision detection of gas-liquid two phase flow parameters will be much more difficult. This project simulates the sea conditions by fluctuant vibration experimental platform, recognize the gas-liquid flow patterns by intelligent data processing tech, construct mathematical model by considering vibration effect to gain the dynamics conditions and principles of flow pattern transformation. The dynamic information of gas-liquid two phase flow is excavated by modern signal processing technology, and the high-precision detection of gas-liquid two phase flow characteristics under the fluctuant vibration condition is realized. Compare the parameter changes disciplinary of gas-liquid flow between fluctuant and swing vibration condition, revealing the differences of the flow patterns and the flow characteristic volatility mechanism that result from different fluctuant vibration conditions. The influence of different vibration factors on the friction coefficient is analyzed, and resistance calculation formula is formed, then practical models and theoretical basis are provided for designing of stable and efficient nuclear powered devices.

作为潜艇核动力装置的重要组成部分——核反应堆，主要以气-液两相流为主体，潜艇在海洋条件下起伏式行驶时，会导致气-液两相流动状态复杂多变，实现起伏式振动状态下气-液两相流动特性参数的准确检测具有相当大的难度。本项目拟通过起伏式振动平台模拟潜艇行驶的海洋环境，运用智能信息处理技术识别气-液两相流型，考虑振动引起的附加惯性力影响，建立两相流动态数学模型，获得流型转变的动力学条件和准则；采用现代信号处理技术检挖掘气-液两相流动力学信息，实现起伏式振动状态下气-液两相流动特性参数的高精度检测，对比起伏式与摇摆式振动状态下气-液两相流动特性参数变化规律，揭示不同振动状态诱导流型及流体动力学特性周期性波动机理的异同；分析不同振动因素对摩擦阻力系数的影响，得出适合于起伏式振动状态气-液两相流摩擦阻力计算关系式，为指导核动力装置在起伏式振动状态下的设计和安全、稳定、高效运行提供实用模型和理论依据。

气液两相流动广泛存在于能源动力和化工等领域，而海洋条件、地震或者非稳定运行使得气液两相流处于起伏振动状态，典型代表如海上核动力漂浮平台和地震下的电站锅炉等。本项目对高频低幅和低频高幅两种振动下不同管道内气液两相流的流型、摩擦阻力及含气率进行了系统的研究，实现了高频低幅起伏振动下水平管和倾斜管以及低频高幅起伏振动下垂直管和倾斜管内气液两相流型的准确界定，绘制了对应的流型图，揭示了不同振动条件下倾角、管径、振幅和频率对流型转换界限的影响规律，建立了高频低幅起伏振动倾斜管内泡状流-起伏弹状流和准弹状流-环状流的流型转换关系式。揭示了高频低幅起伏振动下水平管和倾斜管以及低频高幅起伏振动下垂直管和倾斜管内气液两相流摩擦阻力的变化规律，分析了倾角、管径、振幅和频率对摩擦阻力的影响，评价了现有模型的适用性，分别基于均相模型和分相模型建立了适用于不同起伏振动条件的摩擦阻力计算模型。获得了高频低幅起伏振动下水平管和倾斜管气液两相流含气率变化规律，评价了不同含气率计算模型的适用性，提出了基于流型的含气率计算模型，使得起伏振动条件下气液两相流含气率计算准确的大幅度提高。. 本研究填补了起伏振动气液两相流动特性理论空白，完善了气液两相流动相关理论基础，能够为可能产生起伏振动的能源动力和化工设备的正确设计和安全稳定运行提供理论指导。