Design and Analysis of Conical Curved Agitator for Medium Density Fibre Processing

Agitator is use in various processing industry for fluid mixing. Mixing is the intermingling of two or more dissimilar portions of materials resulting in attainment of a desired level of uniformity either physically or chemically. This work gives approach for performing stress analysis of an agitator of a large mixing vessel used in medium density fiber process plant. The analysis is carried out for total deformation and natural frequencies in agitator body. The agitator is subjected to vibration due to multi-axial forces resulting from bending and tensional loading imposed by the mixing operation. To optimize the mixing percentage of mixture here in this dissertation two special type of paddle type impellers are suggested which are double helical ribbon impeller and anchor impeller. In this dissertation ANSYS software is used for computing structural analysis as well as modal analysis. From structural analysis it is found that all the type of impellers has deformation in acceptable limits i.e. Below 0.025 mm and form modal analysis it is found that double helical ribbon impeller can be resonated by only single operational frequencies i.e. Double helical ribbon impeller blade pass frequency (6.67 Hz) as it come in the six natural frequency band of double helical ribbon impeller i.e. 4.6 Hz 23.61Hz. Since this single frequency affects the system, it is very mush easy to counter that one.