“…The choice between these two methods depends on the hypothesis considered; the accuracy level and the geometry of the study, for example. The analytical method is used for simple geometries (flat plates, for example) and non-complex fluid behaviour (without dependency on other parameters, for example) [11,23,29,32,34] . In the majority of cases, an analytic method cannot solve the question and the numerical simulation is applied [28,45,46,54,63,68] .…”