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Abstract

Accretion flows onto dense structures in star-forming regions plays a crucial role in the formation and growth of stars. These flows, which occur on multiple spatial scales -- from large-scale filaments down to small cores -- are responsible for channelling material onto protostellar objects. Understanding the properties of these flows is vital for developing a comprehensive picture of star formation, yet the detailed mechanisms governing their dynamics remain unclear. In this thesis, I investigate the properties of accretion flows in high-mass star-forming clusters, with a focus on understanding the interplay between gas dynamics, environmental conditions, and the evolutionary stage of the systems. Using interferometric data from the ALMA evolutionary study of high mass protocluster formation in the Galaxy, single dish data from the IRAM 30m observatory and synthetic observations from magnetohydrodynamic (MHD) simulations, I explore how material is transported along filamentary structures and accumulated onto dense cores. The results reveal that accretion flow rates are closely tied to the mass of the cores, following a M^2/3 relationship that supports the tidal-lobe accretion model. I find that flow rates have an increasing trend with respect to their evolutionary stages, suggesting a connection between accretion dynamics and the age of the star-forming system. Additionally, feedback from newly-formed stars is shown to significantly affect the flow structure. In feedback-dominated regions, feeder filaments sustain material flows onto the central clump, emphasising the importance of environmental conditions in shaping the accretion process. Through a multi-scale analysis of accretion flows, I find that the flow rates decrease slightly as we move from large to small spatial scales. This thesis contributes to our understanding of the complex dynamics driving star formation. By integrating observational data with theoretical models, it bridges the gap between the large-scale collapse of molecular clouds and the detailed accretion mechanisms moving material onto forming protostars, offering new insights into how this material is accumulated in star-forming regions.