LBM study on the heat and mass transfer characteristics of the droplet in pressurizer

Abstract

Pressurizer is widely used in the industrial systems, which can maintain the pressure of the system in a certain range. Especially, as the system pressure rises, the spray droplets interacts with the saturated steam in pressurizer to reduce system pressure. In this paper, a heat and mass transfer model of droplet and steam in pressurizer is established through the lattice Boltzmann method (LBM), and the characteristics of moving droplet in steam space with different Reynolds numbers are analyzed. In this paper, these results show that the flow fields on both sides of the droplet have obvious symmetry at low Reynolds number. As the Reynolds number increasing, the wake region of flow field for moving droplets gradually loses symmetry. When the Reynolds number reaches 103 orders of magnitude, the droplet motion begins to appear horizontal deviation. The growth of droplet condensation radius is inhibited with the increase of Reynolds number. When Reynolds number reaches 2600 and Fo = 0.2, the growth of droplet radius stops and then decreases. Due to the influence of inertia force generated by internal circulation flow and droplet movement, as the Reynolds number increasing, the droplet heat transfer rate decreases at first, but begins increasing when Reynolds number raises to about 2000. The calculation results have reference value for the development of spray droplet model of pressurizer.