In order to analyze the relationship between eddy current and time in the opening process of three eccentric butterfly valve, a two-dimensional physical model based on three eccentric butterfly valve was established by using the calculation method provided by Fluent software, and the UDF functions at different times were compiled. The eddy street phenomenon in the opening process of three eccentric butterfly valve was analyzed by using dynamic grid technology and user-defined functions. Numerical simulation was carried out to obtain the vortex velocity and vortex length at different times after opening. The results show that the throat effect is produced in the down flow of the butterfly valve when the three eccentric butterfly valve is just opened. The vibration of the butterfly valve is strong because of the large flow resistance under the small opening of the fluid medium. With the increase of the ope-ning, the flow resistance decreases sharply, and the vibration of the butterfly valve gradually weakens. As a result, strong eddy currents occur around the edge of the three eccentric butterfly plate, and obvious vortex street effect appears at the lower end. With the increase of opening stroke, the eddy velocity decreases continuously, and the eddy length increases first, then slowly decreases, and finally disappears. The flow field of butterfly valve was simulated by finite element method, and the time of vortex street formation and shedding was found. This simulation provides a train of thought for the design, test and use of the three eccentric butterfly valve.
HE Qing-Zhong,LIU Yu-Cong-*,ZHAO Xian-Dan et al. Opening characteristics of three eccentric butterfly valve based on CFD moving grid technology[J]. Journal of Drainage and Irrigation Machinery Engin, 2019, 37(6): 508-512.
FENG Weimin,XIAO Guangyu,YUAN Bo, et al.Comparative analysis of butterfly performance based on numerical simulation[J]. Journal of drainage and irrigation machinery engineering, 2010, 28(4): 315-319.(in Chinese)
HAN Zhijie, LIU Enfu, LIU Zhenyu, et al. Research and optimization of flow field characteristics of three eccentric butterfly valve based on CFD[J].Machinery design & manufacture, 2015(12): 185-189.(in Chinese)
CUI Baoling,SHANG Zhaohui,SHI Ke.Improved design and numerical analysis of butterfly plate structure based on CFD[J].Journal of drainage and irrigation ma-chinery engineering, 2013,31(6):523-527.(in Chinese)
CHEN Jianhui, XIE Yonghui,SHEN Zhongchang,et al. Numerical study on flow separation control of cascades with synthetic jet using dynamic mesh method. [J]. Proceedings of the CSEE, 2013, 33(23):126-133.(in Chinese)