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The tip-leakage flows over an NACA0009 blunt trailing edge hydrofoil with different tip gap width (τ=0.1c and 0.02c, c is hydrofoil chord length) and tip edge rounding (rounding radius r=0, 0.5%c and 1%c) were studied by using SST k-ω turbulent model based very large eddy simulation (VLES) with particular emphasis on understanding the turbulence characteristics and the underlying mechanisms for turbulent loss in the vicinity of the tip gap. Systematic and detailed analysis of the vortex structures, Reynolds stresses, turbulent kinetic energy and tip clearance turbulent loss was made around the hydrofoil with a stationary endwall. Results showed that the Reynolds stress distributions in the tip gap region were consistent with the distributions of the tip clearance vortices, and the magnitude of the normal stresses 〈v′v′〉and 〈w′w′〉 around the tip gap vortices were larger than that of other Reynolds stress components. For the gap τ=0.1c, turbulent kinetic energy and Reynolds stresses of the tip clearance flow were found to be concentrated in the tip separated vortex (TSV) region, the velocity gradient 〈v〉/z and the spanwise normal stress 〈w′w′〉dominated the generation of turbulent kinetic energy in the TSV region; as the tip rounding radius increased, the significant decrease of the Reynolds stresses resulted in a reduction of the tip clearance turbulent loss. For gap size of 0.02c, the strong entrainment of the tip leakage vortex (TLV) on the end-wall boundary layer induced the formation of an induced vortex (IV), which rotated opposite to the TLV. The tip clearance turbulent loss mainly occurred in the TLV and IV regions for the smaller tip gap cases, and its magnitude was increased with the increase of the rounding radius. The underlying mechanism for this tendency was that enlarging the tip clearance increased the normal Reynolds stress 〈v′v′〉 and the velocity gradient 〈v〉/y, which dominated the production of turbulent kinetic energy in the IV region; and it also led to an increase of the Reynolds shear stress 〈v′w′〉 and velocity gradient 〈v〉/z+〈w〉/y), which dominated the generation of turbulent kinetic energy in the TLV region.