Enhanced heat transfer study of gas-solid two-phase flow in spiral flat tube

In order to enhance the heat transfer capacity of spiral flat tubes, the method of combining the spiral flat tube with gas-solid two-phase flow is adopted, and the size of the heat transfer capacity is compared with that of the ordinary round tube under the same conditions. Numerical simulations of the heat transfer characteristics of 61 heat transfer tubes with different structures are carried out by using FLUENT to analyze the heat transfer capacity of the tubes with different gas velocities, flatnesses, and conduction ranges, and the heat transfer enhancement factor, E, and the comprehensive heat transfer performance evaluation factor, ?, were used to evaluate the comprehensive heat transfer capacity of the heat exchanger tube. The results show that the addition of particles can obviously strengthen the gas-phase heat transfer, and the heat transfer enhancement factor is up to 363% compared with that of the common round tube, corresponding to the parameters of the gas velocity of 7 m/s, flatness of 2.4, and the pitch of 200 mm, and the comprehensive heat transfer performance evaluation factor under the same conductivity at the gas velocity of 7m/s shows the change rule of increasing firstly and then decreasing with the flatness increasing.