微细通道内蒸汽直接接触间歇凝结压力振荡特性

Pressure oscillation characteristics of direct contact condensation in a microchannel

为探究微尺度条件下蒸汽直接接触间歇凝结瞬时压力振荡特性,开展了T型微细通道内间歇凝结压力测量实验及频谱分析等。研究发现,在蒸汽温度100℃、蒸汽质量流量0.45g/min、过冷水温度40℃以及过冷水质量流量12.65g/min工况下,间歇凝结压力时域信号在−29.5~8.8kPa之间波动,压力值在2.5kPa附近的概率密度最大。此外,通过频谱分析发现压力频域信号的第一主频为10Hz,与1s内间歇凝结经历的周期数量相近。

In order to investigate the instantaneous pressure oscillation characteristics of steam direct contact intermittent condensation under microscale conditions,experiments and spectral analysis were conducted on the measurement of intermittent condensation pressure in a T-shaped microchannel.It was found that under the working conditions of steam temperature 100℃,steam mass flow rate 0.45g/min,supercooled water temperature 40℃and supercooled water mass flow rate 12.65g/min,the time domain signal of intermittent condensation pressure fluctuates between−29.5kPa and 8.8kPa,and the probability density of the pressure value near 2.5kPa was the largest.In addition,through spectrum analysis,it was found that the first dominant frequency of the pressure frequency domain signal was 10Hz,which was similar to the number of cycles experienced by intermittent condensation within one second.