Tham khảo tài liệu 'hydrodynamics natural water bodies part 9', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Astronomical Tide and Typhoon-Induced Storm Surge in Hangzhou Bay China 187 Fig. 6. A sketch of triangular grid for modeling typhoon-induced storm tide Current velocity It is clearly seen from Figures 7 and 8 that the maximum tidal ranges occur at the Ganpu station T4 . Thus it is expected that the maximum tidal current may occur near this region. The tidal currents were measured at four locations H1-H4 across the estuary near Ganpu. These measurements are used to verify the numerical model. Figures 9 and 10 are the comparison between simulated and measured depth-averaged velocity magnitude and direction for the spring and neap tidal currents respectively. It is seen that the flood tidal velocity is clearly greater than the ebb flow velocity for both the spring and neap tides. The maximum flood velocity occurs at H2 with the value of about m s while the maximum ebb flow velocity is about m s during the spring tide. During the neap tide the maximum velocities of both the flood and ebb are much less than those in the spring tide with the value of m s for flood and m s for ebb observed at H2. The maximum relative error for the ebb flow is about 17 occurring at H2 during the spring tide. For the flood flow the maximal relative error occurs at H3 and H4 for both the spring and neap tides with values being about 20 . In general the depth-averaged simulated velocity magnitude and current direction agree well with the measurements and the maximal error percentage in tidal current is similar as that encountered in modeling the Mahakam Estuary Mandang Yanagi 2008 . 188 Hydrodynamics - Natural Water Bodies Fig. 7. Comparison of the computed and measured spring tidal elevations at stations T2-T6. computed o measured Astronomical Tide and Typhoon-Induced Storm Surge in Hangzhou Bay China 189 Fig. 8. Comparison of the computed and measured neap tidal elevations at stations T2-T6. computed o .
