Additive Manufacturing (AM), and in particular Laser Powder Bed Fusion (L-PBF), enables the fabrication of complex internal geometries that are not feasible with traditional manufacturing techniques such as casting or milling. This capability is especially beneficial for gas turbine components, where advanced cooling channel designs are required to sustain high thermal loads and improve overall engine efficiency. However, a direct consequence of the AM process is the formation of unique surface roughness (SR) patterns, which affect both pressure loss and convective heat transfer (HT) mechanisms. In particular, AM-induced SR tends to be irregular and highly stochastic in nature, deviating from traditional roughness characterizations based on sand grain analogs.