School of Naval Architecture and Ocean Engineering Jiangsu University of Science and Technology Zhenjiang 212003 China;
State Key Laboratory of Tropical Oceanography South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 ChinaSouthern Marine Science and Engineering Guangdong Laboratory Guangzhou 511458 China;
State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of Oceanography Ministry of Natural Resources Hangzhou 310000 China;
internal tides; South China Sea(SCS); resonant interactions; rotary spectra; parametric subharmonic instability;