Estudo de uma planta piloto de agitação utilizando fluido dinâmica computacional

Abstract

The fluid agitation operation is generally considered to be one of the simplest operations seen in the industry. In fact, in relation to operations, such as distillation, agitation has a simpler assembly and geometry. However, its design complexity makes it impossible to design equations that can predict all the phenomena that occur in its interior, this is due to the large amount of geometric variables that must be considered. Experimental analyzes are generally limited to the parameters that are available, so the correlations that emerge from these experiments cannot be applied generally. Computational techniques, together with the increase in the calculation capacity of current processors, have been gaining more space due to their high capacity for predicting phenomena, low cost and flexibility in the development of new experiments. This work aims to analyze the influence of geometric parameters impeller diameter, width and blade angle on power consumption and flow profiles in a 50 liter agitation plant, using fluid dynamics techniques as a methodology for the analysis. computational (CFD), more precisely the ANSYS application suite, where FLUENT was chosen for the assembly and resolution of computational models. With the results, it was observed that the use of polyhedral elements produced meshes with fewer elements compared to meshes used in the literature, however, the results tended to be in agreement with the literature and close to the experimental data used as a comparison, considering the different parameters geometrical tests, however, the data obtained with empirical correlations did not show a good approximation. Therefore, it is concluded that the computational techniques were sufficient to represent the phenomena inside the tank, the impeller diameter and blade width parameters impacted the power consumption (number of power) and little changed the flow profiles, the blade angle impacted both power consumption and flow profiles, as these two factors are closely intertwined. The comparison of the results with the empirical correlations, Nagata (1975) and Nishikawa (1979), had little effect, due to the low similarity of the results obtained by these equations and experimental data.