Experimental investigation on pressure oscillation induced by steam lateral injection into water flow in a horizontal pipe

Abstract

Pressure oscillation induced by steam lateral injection into water flow in a horizontal pipe was investigated experimentally. The pressure oscillation signals were obtained by four dynamic pressure transmitters. Six typical pressure oscillation waveforms were observed, which can be classified into two types: pulse oscillation and continuous oscillation. The characteristics of six typical oscillation probability density function (PDF) are described, which are highly correlated with the types of pressure oscillation. Based on PDF, the effects of steam mass flow rate, subcooled water flow rate and temperature on the amplitude of pressure oscillation distribution were analyzed. Furthermore, the first and second dominant frequency were obtained through the fast Fourier transform (FFT). The pressure oscillations at different measurement points were found to have the same first dominant frequency. The first dominant frequency increases and then decreases gradually with the rising of subcooled water temperature at the low steam mass flow rate. While the first dominant frequency decreases with the increasing of subcooled water temperature at high the mass flow rate. In addition, when subcooled water temperature higher than 60 ℃, the first dominant frequency was found that it increases with the rising of subcooled water flow rate and decreases with the increasing of subcooled water temperature.