# Experimental Analysis of Shale Cuttings Migration in Horizontal Wells
## 1 Introduction
[PERSON] utilized the Herschel-Bulkley and power law models in analyzing the foam system to investigate the impact of rheological models on cuttings transport in both concentric and eccentric annuli during foam drilling operations [18]. In addition to experimental studies and theoretical models, numerical simulation methods have also been introduced into the research field of cuttings migration. [PERSON] conducted a study on the flow dynamics characteristics of cuttings in vertical wells using the computational fluid dynamics (CFD) simulation method [19]. [PERSON] also utilized the CFD method to calculate fluid dynamics characteristics in the presence of eccentric drilling tools. The study employed the Reynolds stress model to analyze turbulent flow and conducted a sensitivity analysis of the parameters [20]. [PERSON] conducted a comparative analysis of the rheological properties of water-based and oil-based drilling fluids [21]. The findings revealed that oil-based drilling fluids exhibited superior viscoelastic characteristics and borehole cleaning efficiency in cuttings transport experiments, despite possessing comparable viscosity and density to water-based drilling fluids. Drawing upon the principles of particle flow mechanics, [PERSON] employed a numerical simulation approach to investigate the migration of cuttings, identifying three distinct flow pattern regions and validating the algorithm's accuracy through comparison with experimental data [22]. [PERSON] employed the Lagrangian-Eulerian/discrete element method (DEM) to investigate particle flow, inter-particle collision, and particle-wall collision dynamics [23]. [PERSON] utilized computational fluid dynamics (CFD) and the Euler-Euler (EE) multiphase model to simulate the behavior of cuttings migration. Apart from analyzing drilling parameters and mud properties, the reflection coefficient was incorporated to characterize diverse wellbore conditions [24]. [PERSON] employed a comprehensive dimensional approach to address the issue of cuttings migration that included the consideration of non-Newtonian behavior, more precise shear thinning and yield analysis, as well as the scaling of wellbore parameters to a laboratory environment [25]. The most common cuttings are spherical particles, but there are also many non-spherical particles. For example, the cuttings of shale are flaky, which leads to obvious differences in their migration laws. [PERSON] analyzed the impact of sphericity and Reynolds number on the resistance coefficients of particles of different shapes, including sphere, cube, octahedron, tetrahedron, disk, cylinder, and other shapes, using experimental data [26]. [PERSON] utilized the experimental method of solid particles settling in a Newtonian fluid to develop a resistance coefficient model for nine groups of cuttings with varying particle sizes in a power-law fluid [27]. To investigate the behavior of various particles, including those utilized for cuttings and proppant purposes, [PERSON] conducted experiments involving three primary particle shapes (spherical, cubic, and cylindrical) and developed eight distinct particle sphericity configurations [28]. [PERSON] conducted experimental research on the settling behavior of spherical particles in both viscoelastic and non-viscoelastic fluids [29]. [PERSON] employed a combination of the Boltzmann method and the discrete element method to investigate the migration patterns of polygonal particles, subsequently conducting an analysis of their mechanical properties [30]. In conclusion, the existing research primarily concentrates on experimental investigations and theoretical examinations of spherical particles, with limited exploration of flaky particles in shale. Moreover, there is a deficiency in the analysis of the cuttings migration patterns in horizontal shale wells, resulting in challenges in accurately depicting the flow dynamics of particles and fluids on the cuttings bed.