ZHENG Xinqian，LIN Yun，ZHANG Yangjun，BAMBA Takahiro，TAMAKI Hideaki，YANG Mingyang; Asymmetrical Self-Circulating Casing Of Centrifugal Compressor with Circular Arc Grooves Location，2011.6.15-2031.6.15，Chinese Patent，ZL 201010110230.5。