Temperature and deformation analysis of ship hull plate by moving induction heating using double-circuit inductor

Abstract This paper mainly investigated temperature and deformation behavior of ship hull plate by moving induction heating using double-circuit inductor with opposite-direction current and gap (ODIG). Mutually-coupled electromagnetic-thermal (EMT) analysis considering temperature-dependent material properties was iteratively implemented at each moving step of inductor, followed with thermal-mechanical (TM) analysis to obtain thermal deformation, and then validated by experiment. Effects of three technological parameters on thermal forming behavior (maximum temperature Tum , breadth b , depth h ) and transverse thermal deformations (shrinkage δ z and bending angular θ z deformation) were analyzed, respectively. Besides, simplified analytical prediction for δ z , θ z were derived based on inherent strain and plate strip, and compared with those from TM analysis. Finally, composite quality indicator f was constructed through using Tum , b , h by PCA method and utilized to determine optimal shape parameters for ODIG based on Taguchi method, which were compared with those through using δ z and θ z , respectively. The results indicate that Opt-f can achieve the same f , δ z , θ z as those from Opt-S and Opt-B, and the best combination is C 1 4 C 3 4 T 2 4 Hy 1 . Therefore, f can be effectively utilized to determine optimal ODIG inductor in order to improve transverse thermal deformations ( δ z , θ z ).