蒸汽浸没射流压力振荡特性实验研究

为指导Ⅰ型鼓泡器排放管的结构设计，对常压工况下不同蒸汽质量流速（150～500 kg/(m²·s)）、池水过冷度（18～68 ℃）、开孔直径（10、16 mm）和孔数（单孔、双孔）蒸汽浸没射流的压力振荡特性开展实验研究。结果表明：不同开孔结构下的振荡强度均随蒸汽质量流速的升高或池水过冷度的降低而先增大后减小；当孔径增大或孔数增多时，达到稳定冷凝所需的最小蒸汽质量流速降低，流型转变导致振荡强度减小。不同开孔结构下的振荡主频均主要受池水过冷度和开孔直径的影响，且随过冷度的降低或孔径的增大而减小。孔数变化对主频的影响是多重的，但总体效果弱于孔径变化。通过对主频实验值进行拟合，获得了由池水过冷度和排放孔径表征的半经验关系式，相对误差在±20%以内。

Experimental Investigation on Pressure Oscillation Induced by Submerged Steam Jet

In order to guide the structure design of the Ⅰ-type sparger, the pressure oscillation characteristics of the submerged steam jet under different steam mass flow fluxes (150-500 kg/(m²·s)), pool water subcoolings (18-68 ℃), discharge hole diameters (10 mm and 16 mm) and discharge hole number (single-hole and double-hole) at the condition of atmospheric pressure were studied experimentally. The results show that the pressure oscillation intensity of the steam jet through different spargers both increases first and then decreases with the increase of steam mass flow flux or the decrease of pool water subcooling. When the discharge hole diameter or the discharge hole number increases, the minimum steam mass flow flux required to main the stable condensation decreases and the transition of flow pattern leads to the decrease of oscillation intensity. The dominant frequency of pressure oscillation is mainly affected by the subcooling degree of pool water and the discharge hole diameter for different spargers, and decreases with the decrease of the former or the increase of the latter. The influence of the discharge hole number on the dominant frequency is multiple, but the overall effect is weaker than the change of discharge hole diameter. By fitting the experimental dominant frequency, an empirical relation regarding to the pool water subcooling and discharge hole diameter was obtained, and the relative error between the prediction and the experimental values is within ±20%.