中文摘要：

以截面尺寸为50 mm×2 mm的矩形并联双通道为实验本体,进行12~15 MPa的压力下密度波流动不稳定与沸腾临界的实验研究。研究发现：在高压条件下,随着压力和质量流速的增加,发生沸腾临界的热工参数范围扩大,而流动不稳定区域相应缩小。通过将热工参数无量纲化,在相变数（Npch）-过冷度数（Nsub）图上绘制了沸腾临界线及不稳定边界,揭示了热工参数对流动不稳定与沸腾临界存在区域的影响机制。

英文摘要：

An experimental investigation has been made on flow instability and boiling crisis in a 50 mm×2 mm parallel rectangular channels at the pressure of 12-15 MPa. In the experiment, it has been found that the thermal parameter range of boiling crisis was extended, while the flow instability zone was reduced with the increase of pressure and mass velocity. And the boiling crisis curve and flow instability boundary line was drawn in Npch-Nsub pictures to analyze the effect mechanism of the thermal parameters on distribution regions.