###### Abstract  
This study aims to investigate the aerodynamic analysis of a Darrieus-type vertical axis wind turbine (VAWT) using the Lattice Boltzmann Method (LBM). The objective is to assess the accuracy and performance of the meshless LBM approach in predicting torque coefficients, velocity, turbulence intensity, and vorticity distributions for VAWT aerodynamic analysis. Two turbulence modelling approaches, Large Eddy Simulation (LES) and Reynolds-Averaged Navier-Stokes (RANS), are employed to model the flow domain. The central problem revolves around comparing the performance of different turbulence models based on their agreement with experimental results for power and torque coefficients. The findings demonstrate the effectiveness of the WALE turbulence model in achieving the best agreement with experimental data. Overall, the study provides valuable insights into applying LBM in VAWT aerodynamic analysis and highlights the advantages of the meshless approach compared to traditional CFD methods. L pacs: 12.30.-c, 12.30.-d, 12.30.  
industrial problems [2]. This study introduces a novel approach that involves solving the Boltzmann equation, which describes the statistical distribution of particles in a fluid in phase space, instead of using the Navier-Stokes equations that describe the flow of a Newtonian fluid under the continuum assumption. Particle-based approaches offer several advantages in obtaining discrete solutions for flow fields. The lattice Boltzmann method (LBM) is a valuable tool for linking the behaviour of particles at both macroscopic and microscopic scales. It accomplishes this by utilizing microscopic models and mesoscopic kinetic equations. Essentially, LBM constructs simplified kinetic models that encapsulate the essential physics of microscopic phenomena. These models are designed to ensure that the macroscopic properties derived from them conform to the desired macroscopic equations, thereby facilitating a comprehensive understanding of the system under investigation. Furthermore, LBM allows for reduced computational costs by utilizing a lattice structure. This approach effectively simulates continuum flows, unlike traditional particle-based methods that can produce unstable solutions when the number of particles increases. Additionally, traditional particle-based approaches may have limited accuracy in multi-dimensional flows, and it can be challenging to derive error estimates as the sample points do not have fixed positions. Overall, the application of the Boltzmann equation solved using the lattice Boltzmann method presents a promising alternative to traditional numerical methodologies in CFD, overcoming some of their limitations and providing new insights into flow field simulations. LBM offers several advantages over traditional CFD methods, particularly in handling complex geometries and boundaries. Researchers have shown that LBM is highly suitable for simulating intricate geometries and complex boundary conditions [3; 4]. The flexibility of the lattice-based grid structure in LBM allows for easy representation of irregular geometries and accurate capture of flow features. Moreover, LBM excels in simulating multi-scale and multiphase flows. Recent studies have demonstrated the capability of LBM in microfluidics applications [5] and multiphase flows with phase change phenomena [6]. The mesoscopic nature of LBM enables accurate modelling of flow behaviour at different length scales, leading to improved accuracy in numerical predictions. Efficient parallelization is another strength of LBM, enabling high-performance computing for large-scale simulations. This is particularly advantageous for turbulent flow simulations and aerodynamic analyses. Researchers have successfully employed LBM in simulating turbulent flows with excellent scalability and computational efficiency [7; 8]. Furthermore, LBM provides a natural framework for incorporating complex physics, such as thermal effects and fluid-structure interactions.