CFD based form factor determination method

Scaling of wetted-transom resistance for improved full-scale ship performance predictions

“…1) and the form factor in model and full-scale becomes equal. This hypothesis (Hughes, 1954) was thoroughly tested by Korkmaz et al (2020Korkmaz et al ( , 2021Korkmaz et al ( , 2019a, and confirmed that the form factors in model and full-scale are nearly the same when there is no flow separation in the flow, and an appropriate friction line is used. In order to disregard the The transom form factor values have been calculated using the numerical friction line (Korkmaz et al, 2019b) and plotted in Fig.…”

“…The importance of the friction line for the CFD based form factors cannot be overstated since the validity of the form factor hypothesis (Hughes, 1954) entirely depend on it. Earlier studies (García Gómez, 2000;Toki, 2008;Pereira et al, 2017;Terziev et al, 2019;Wang et al, 2015;Korkmaz et al, 2020Korkmaz et al, , 2021Raven et al, 2008;Wang et al, 2015;Dogrul et al, 2020) indicated that there are scale effects on form factors when the ITTC-57 model to ship correlation line is used. However, scale effects on form factors were reduced with the usage of Katsui line (Katsui et al, 2005), and it nearly disappeared when numerical friction lines of the same code and turbulence model were used as the double-body RANS computation (Korkmaz et al, 2020).…”

Scale effects and full-scale ship hydrodynamics: A review

“…This makes it possible that some of the differences attributed to scale effects may be alleviated by underlying uncertainties or absorbed in correlation allowances. An account of the pertinent background and issues are explored by Korkmaz et al (2021). Since the Prohaska test is carried out at low speeds, the combination of experimental and numerical uncertainty obscure the presence or absence of scale effects.…”

An experimental and numerical hydrodynamic study on the Argentinian fishing vessels

“…The force coefficient decomposition involves determining the form factor k. In this work, the values of k were obtained numerically by the double-hull CFD method and experimentally by Prohaska's method. It is interesting to note that in the 1978 ITTC Performance Prediction method, the form factor has been identified by the CFD/EFD Methods ITTC Specialist Committee as one of the major causes of uncertainties, specifically due to the Prohaska method [4,7]. Although it is beyond the scope of this work, the obtained values of k will serve as the basis for future research that seeks to answer the question of whether CFD-based form factors can be an alternative or supplement to the Prohaska method.…”