[Objectives] The purpose of this study is to solve the problem of insufficient energy dissipation and flow disorder in the stilling pool with low Froude number. A new type of auxiliary energy dissipator-V-shaped pier is proposed, and the forward rate of hydraulic jump position P is introduced as a new evaluation index to quantify the effect of hydraulic jump regulation. The main purpose is to systematically study the influence of Froude number Fr, V-shaped pier angle θ, row spacing γ, first row pier position Γ, pier height ratio ξ and contraction ratio β on energy dissipation rate η and forward displacement rate of hydraulic jump position P, reveal its energy dissipation mechanism, and provide optimal design parameters for practical engineering. [Methods] The research method of combining physical model test and numerical simulation is adopted. The physical model is made of organic glass and PVC, including upstream water tank, test section, triangular water weir and backwater system. The total length of the stilling basin model is 933 mm and the width is 200 mm. The experimental design based on L₁₈ (3⁶) orthogonal table was used to evaluate the effects of six factors and three levels on η and P efficiently. At the same time, a three-dimensional numerical model using the RNG k-ε turbulence model was established to simulate the optimal V-shaped pier condition and the non-pier condition. The energy dissipation characteristics such as flow field structure, turbulent kinetic energy dissipation rate and turbulent scale were analyzed. [Results] The orthogonal test shows that the Fr has the most significant effect on the energy dissipation rate η, and η increases significantly with the increase of Fr (2.77- 4.91). Under the optimal scheme, η reaches 95.58%. For the forward rate P of the hydraulic jump position, the first row pier position Γ and the pier height ratio ξ have the greatest influence, and the P is 49.42% under the optimal scheme. The analysis of variance verifies the significance of each factor, and determines the global optimal parameter combination at Fr=4.91. The numerical simulation reveals the flow mechanism in depth. The results show that compared with the working condition without V-shaped pier, the V-shaped pier arrangement reduces the maximum velocity of the pre-jump section from 2.69 m/s to 1.63 m/s, a decrease of 39.4%, which significantly shortens the flow field homogenization distance. The peak value of turbulent kinetic energy dissipation rate ε near the first row of piers is 3.10 J/kg/s, which is 14.52% higher than that without V-shaped piers, indicating that energy dissipation is enhanced by strong shear and vortex action. The turbulence length scale L_T near the pier is reduced to about 0.02 m, which effectively suppresses the development of large-scale vortices. After the second row of piers, the L_T is homogenized to about 0.10 m, and the vortex scale at the apron is reduced by 81.25% to 0.03 m, reflecting the multi-stage vortex synergy energy dissipation mechanism. [Conclusions] The V-shaped pier is an efficient auxiliary energy dissipator with low Froude number stilling basin. Its unique geometric design enables a multi-stage energy dissipation mechanism that includes flow separation, guidance, and generation of synergistic multi-scale vortices. The optimal parameter combination of V-shaped pier geometry and arrangement is determined by orthogonal test and variance analysis, which provides a scientific basis for its optimal design. The optimal parameter combination realizes the collaborative optimization of energy dissipation rate (η=95.58%) and hydraulic jump position control (P=49.42%). Finally, it is determined that the V-shaped pier fundamentally optimizes the flow field, significantly improves the flow stability and energy dissipation efficiency, and reduces the downstream scour risk through the mechanisms of diversion, impact, shear and multi-stage vortex dissipation. This study can provide theoretical basis and practical guidance for the design of energy dissipator in similar water conservancy projects. The follow-up work should focus on establishing the optimal parameter combination relationship in a wider range of Froude numbers.