# CFD Design Performance Analysis for a High-Speed Propeller
## 3 Materials and Methods  
This study did not use any artificial intelligence tools; we still had to use artificial intelligence (Chat GPT 4) to have a scan on the internet to identify most relevant paperwork in this field. We did that to study the most relevant methods utilized. Fluid Dynamics is applied in a wide variety of fields that require the study of the behavior of gases and liquids. Simplistically speaking, Computational Fluid Dynamics (CFD) modeling provides three-dimensional, time-accurate information about fluid motion, in general, but also about particle trajectories or surface dynamics. The development of new fluid modeling algorithms, combined with modern computational architectures, now allows engineers to simulate the behavior of fluids with a fidelity that rivals that of a geometric model (3D CAD model) of the system to be studied and for which information on the properties of the fluids can be entered. Several aspects can be successfully studied, such as speeds, flow rates, current line trajectories, pressure distribution on certain contours, etc. The ANSYS CFX module [23] is one of the best-known and most powerful fluid dynamics solvers. It is a general-purpose tool that can simulate a wide range of processes, such as internal flow, aerodynamics, combustion, conjugate heat transfer, etc. ANSYS simulation software dedicated to the study of fluid dynamics allows the determination of the impact of fluid flow on a product both in the design and manufacturing phases, as well as during its operating time. It contains physical models for turbulence, reactive flows, heat transfer, acoustics and multiphase flows. It is also one of the most scalable software packages on the market, being able to achieve 93% efficiency on computing systems with 200,000 cores. The study of the Fluid-Structural Interaction (FSI) highlights both the flow of the fluid and the way in which it encounters a solid structure. The fluid flow can exert pressure and/or loads on the structure. These loads can cause structural deformations significant enough to alter the flow of the fluid itself. Undesirable effects can increase as the level of interaction between fluid and structure increases. Simulations made with ANSYS applications allow a deeper understanding of the phenomena that occur, thus ensuring safety and reliability. Modeling with ANSYS involves, in principle, going through some work steps, but it should be noted that it is practically impossible to detail the working mode. Next, some essential aspects of working with ANSYS will be mentioned. For the study presented in this paper, a high-speed propeller was used, with a diameter of 14 cm, with 3 fixed blades, as can be seen in Figure 1.  
Also, fluid domain geometry was generated. The fluid domain geometry consists of two domains:  
one region, near the propeller consists of a rotating disk surrounding the propeller (see Figure 2). Figure 1: Propeller geometry. Figure 2: Domain geometry near the propeller. an external cylindrical fixed domain, 1 m in front of the propeller, 3 m behind the propeller and 1 m around the propeller (see Figure 3). Meshing is a fundamental step in all analysis processes within ANSYS. It involves dividing geometries into small polygons, enabling each polygon to be individually processed for accurate result generation [24]. A finer network creates better results. However, excessive network refinement can lead to long processing times. In this paper, mesh was automatically generated, and consists of 24,692 nodes and 130,503, with a small resolution on the rotating domain and a larger resolution on the external domain (see Figures 4 and 5). Figure 4: The rotating domain mesh for propeller. Figure 3: External domain geometry. To ensure the reliability and mesh independence of the numerical results, a mesh sensitivity analysis was conducted using three levels of mesh resolution: coarse, default (used in the study) and fine.