“…The past research also provides perspectives for future directions. In the early phases of sub-channel thermal hydraulic analysis, the focus of research articles was mostly on analytical and experimental work done for the creation of sub-channel analysis codes, [23], [24], [25], [26], [27], [28], [29], [30], [31], [32], [33], [34], [35], [36], [37], [38], [39], [40], [41], [42]. These attempts were made to increase the accuracy of CFD predictions and to derive models from CFD for novel fuel geometries, decreasing the time needed for fuel assembly design and optimization, improving safety, and running the fewest number of tests possible to conserve resources and time.…”