LIU Shanghua, SUN Baozhi, SHI Jianxin, et al. Effect of helically coil diameter on thermal-hydraulic inhomogeneity in helically coiled tube[J]. CIESC Journal, 2014, (z2): 148-154.
LIU Shanghua, SUN Baozhi, SHI Jianxin, et al. Effect of helically coil diameter on thermal-hydraulic inhomogeneity in helically coiled tube[J]. CIESC Journal, 2014, (z2): 148-154.DOI: 10.3969/j.issn.0438-1157.2014.z2.022.
A three-dimensional "unit pipe" physical model of helically coiled steam generator is established based on the similarity theory
two fluid model considering mass
momentum and energy transfer is used
and describe the process of two fluid phase through the bulk boiling model. Numerical investigation on the flow and phase change in the helically coil tubes with the helically coiled diameter 200 mm
500 mm and 1718 mm is thereby carried out. Simulation results show that the obvious secondary flow is formed due to the centrifugal force
and the smaller the helically coiled diameter and the greater the velocity is
the more obvious the secondary flow is. In two-phase flow area
the helically coiled diameter has great influence on the distribution of two-phase flow. In addition
the smaller the helically coiled diameter is
the larger the temperature difference is due to the effects of vapor-liquid separation and the secondary flow. The temperature difference of circumferential wall temperature on the single-phase flow area is dramatically larger than that of two-phase flow area.