## 1 Introduction  
The interest in energy dissipation in hydraulic structures has developed at an appropriate time, given the significant increase in the construction of large dams worldwide since the 1950s [1]. The design of hydraulic energy dissipators for these dams is often a challenge, especially when dam parameters include high water head and large discharge [2]. The hydraulic jump [3] and ski-jump [4] are common energy dissipation features, as is the plunge pool [5]. However, when a dam is built on a hyperconcentrated sediment-laden river, energy dissipation is complicated by sediment effects [6]. Energy dissipation is an important issue in the design of a hydraulic structure. The hydraulic characteristics of the impinging jet or plunge pool of an energy dissipator have been extensively studied in fresh water. Deep outlets with a plunge pool should be considered a standard, common design for energy dissipation [7] and flushing sediment from reservoirs [8]. Nappe flows, in which water is dropped through the atmosphere into a pool or water cushion, exhibit rapid diffusion of the jet in the pool, dissipating the energy of the falling water and attenuating fluctuations at the base of the pool [9]. Many papers have been published on methods to determine the shape and size [10] of a plunge pool and the bottom slab thickness [11], and others have paid special attention to hydraulic plunge pool scour [12]. The safety of plunge pools has also been a subject of close attention, e.g., the hydraulic pressure [13] and uplift force [14]. Other research has concentrated on the mechanism of the impinging jet [15]. The entire flow of an energy dissipator is divided into a free jet region, an impinging region, and wall jet region. [PERSON] and [PERSON] [16] discussed the time-averaged characteristics of an impinging jet and [PERSON] et al. [17] presented an experimental study of the turbulent structure on the centerline of a two-dimensional impinging jet. Energy dissipation depends on the turbulence of flow and the fluctuation of turbulent flow based on the formation of coherent structures [18; 19]. Using experiments and calculations, [PERSON] et al. [20] concluded that the vortex structure in a wall turbulent flow takes the form of a hairpin. [PERSON] et al. [21] systematically analyzed, summarized, and compared popular vortex identification criteria and vortex structure recognition methods. The scale, intensity, and density of vortex structures have also been studied [22; 23]. With the continued development of experimental technology, new advanced simulation methods [24] and devices [25], such as direct numerical simulation (DNS) [26], large eddy simulations (LES) [27], and particle image velocimetry [28], have been used to research turbulence characteristics. However, turbulent flow is a complicated subject, and many details describing turbulent structures still remain inconclusive. Hyperconcentrated sediment-laden flow has been studied using experiments and simulations over the past century as either a Newtonian fluid [29] or Bingham fluid [30]. The presence and characteristics of particles have been found to affect the turbulent structure of a suspension [31]. [PERSON] et al. [32] simulated porous turbulent flows using DNS and observed that stream-wise turbulence intensity decreased in a porous duct. The turbulent velocity profile in sediment-laden flows has been studied by experiments [33] and simulations [34; 35]. [PERSON] and [PERSON] [36] performed a theoretical analysis and determined that sediment suspension increases main flow energy loss and weakens turbulent diffusion in the vertical direction, and increases the velocity gradient.