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During the grain drying production, the heat transfer loss was great, and flue gas heat can not be efficiently transferred, resulting in low heat transfer efficiency and other problems. The gas-phase rotary heat exchanger integrating shell-and-shell and shell-and-tube heat exchanger was taken as the research object, and the key components of the spiral grooved tube were optimized based on the field synergy and thermodynamic theory. The influence of spiral grooved tube parameters on heat transfer performance was investigated. Pitch, groove depth and inner/outer diameter ratio were taken as test factors, and nussle number and resistance coefficient were used as evaluation indexes. Three-factor five-level quadratic orthogonal rotary combination experiments were carried out. Multi-objective optimization method was used to determine the optimal parameter combination, and nussle number was 164.637 and resistance coefficient was 0.348 when the pitch was 24.845 mm, the groove depth was 1.753 mm, and the inner/outer diameter ratio was 0.897. Verification experiments were carried out on the optimization results, and the experimental results were basically consistent with the optimization results. The average field synergy angle of the spiral grooved tube was decreased by about 2° compared with that of the circular tube, revealing the distribution characteristics of the field synergy angle in the inlet, outlet and intermediate sections of the spiral grooved tube bundle placed in the shell range, and the field synergy effect was increased in the overall range, which was concluded to be in line with the field synergy principle. The enhanced heat transfer comprehensive performance index was utilized for evaluation, and the results showed that the thermal performance factor of spiral grooved tube heat exchanger was between 1.031 and 1.267, which verified the rationality of spiral grooved tube in heat exchanger application.