温度对狭窄缝隙流动阻力系数影响的试验研究

Study on Effect of Temperature on the Narrow Gap Ressistance Coefficient Test

压水反应堆内冷却剂旁漏流流道尺寸多是狭窄缝隙,狭窄缝隙尺寸很敏感,很容易受到系统压力、压差、温度、振动等因素的影响。微小的尺寸变化又会引起阻力系数明显改变,导致试验测得的雷诺数与阻力系数关系曲线与流体动力学基本原理相悖。本文通过开展恒温和升温条件下的狭窄缝隙流动阻力系数试验,研究温度变化对狭窄缝隙流动阻力系数的影响规律。升温试验中维持系统压力、试验本体压差、流量不变,逐渐升高试验流体温度,获得不同温度下的试验本体流动阻力系数。试验结果表明试验流体温度从23℃上升至52℃时,试验本体狭窄缝隙尺寸由于热胀冷缩导致接缝面更贴合,压紧力增大,流动阻力系数增幅达8%。

The coolant leakage and bypass flow channel in PWR is mostly a narrow gap.The size of narrow gap is sensitive to be easily affected by system pressure,differential pressure,temperature,vibration and other factors.Small size changes will cause significant changes in resistance coefficient,resulting in the measured Reynolds number and resistance coefficient curve contrary to the basic principles of fluid dynamics.In this paper,the study on effect of temperature change on the flow resistance coefficient in narrow gap is conducted under the conditions of constant temperature and temperature rise.During the temperature rise test,the system pressure,the differential pressure and flow of the test body stays unchanged,and gradually increase the temperature of the fluid,then obtain the resistance coefficient of the test body under different temperature.The test results show that when the temperature of the test fluid rises from 23°C to 52°C,the narrow gap of the test body is more closely fitted due to thermal expansion and cold contraction,and the flow resistance coefficient increases by 8%.