drill bit, and the speed of movement all influence the friction coefficient (\(k\)). Additionally, both the friction coefficient (\(k\)) and the geometry of the nozzle play a crucial role in the nozzle's motion and the generation of eddy currents [6; 7; 8; 9; 10]. [PERSON] et al. [11; 12] used the standard \(k\)-\(\varepsilon\) two-equation model to analyze the flow field in the wellbore of the nozzle with varying back nozzle parameters. It is proposed that the self-propelled water jet nozzle will generate a vortex zone under the combined action of the front and rear nozzles. The size and position of this vortex will have an impact on both the efficiency of the water flow and the friction between the high-pressure hose and the water jet nozzle. Additionally, the resistance experienced by the nozzle could potentially shorten its service life. In terms of nozzle structure, [PERSON] et al. [13] studied the jet characteristics of nozzles with various structures using the straight cone nozzle model invented by Soviet scholar [PERSON]. [PERSON] and their self-developed test platform. The straight cone nozzle exhibits excellent structural parameters and performance. [PERSON] et al. [14; 15; 16] investigated the impact of various nozzle structures on dynamic pressure conversion, jet velocity, and turbulent kinetic energy conversion by creating nozzle models with different shapes and employing 2023 version of Fluent and Gambit software. For two kinds of conical nozzles with different structures, the velocity, pressure, medium, and other physical quantities of high-pressure water jet flow field are numerically simulated and analyzed by the computational fluid dynamics method. The SIMPLEC algorithm is used to obtain a residual error of less than \(10^{-4}\), and the two nozzles are compared. [PERSON] [17] provided a quantitative analysis of the external parameters of the ultra-high-pressure water jet nozzle and the optimization method of jet core parameters. [PERSON] et al. [18] obtained the optimal high-pressure nozzle structure and striking distance through structural design, model establishment, numerical simulation, and result analysis of high-pressure nozzles. [PERSON] et al. [19; 20; 21] studied a simulation model by calculating the pressure pulse and shear force generated by turbulent kinetic energy. Based on the \(k\)-\(\varepsilon\) model, the low Reynolds number non-Newtonian model, and the RKE and RNG versions of the non-Newtonian damping function, they used these tools to numerically simulate the turbulent flow of the drag-reducing fluid within the pipeline. [PERSON] [22] proposed a full-scale computational fluid dynamics CFD model that utilizes three types of tanks for modeling: circular, square, and square-arc angle tanks. Using fluent software, the optimal arrangement of the number of inlets, the inlet position, the inlet angle, and the number of nozzles on each inlet is reconfigured. These equations govern the average turbulent flow of water, enabling the creation of an optimized fluid domain. [PERSON] et al. [23] leveraged ANSYS Fluent to solve the Navier-Stokes (N-S) equation for the average turbulent flow field. By adopting a complex conjugate eigenvalue approach based on the velocity gradient tensor, they were able to examine the flow dynamics, turbulence, and vortex structures within the average turbulent flow field. It is found that the convex contour surface inside the elbow is the key eddy current generating surface. In summary, while the research on nozzle flow fields is abundant, there is a scarcity of studies examining the impact of the rear nozzle inclination angle and nozzle diameter parameters on convection and operational conditions within the pipeline environment of the nozzle. In this paper, a numerical simulation analysis of the flow field within a pipeline for a self-propelled water jet nozzle will be conducted using Fluent.