Design of a Tofu Stirring Blade to Reduce Product Residue
Keywords:
Tofu agitator blade, flow patterns, CFD simulation, mixing efficiencyAbstract
This research aimed to develop and design a tofu stirring blade for the tofu molding stirring process, in collaboration with a soybean processing company, to address the problem of manual stirring, where operators were required to wear gloves and stir the tofu directly in the tank. The amount of tofu residue remaining at the bottom of the tank after stirring was required to be less than 1 kilogram. This research developed three stirring blade design concepts that were consistent with the operating principles and compatible with the factory’s existing stirring machine, to make the molding stirring process faster, easier to operate, controllable by a single operator, and to improve hygiene standards in the production line. Engineering analysis employed Computational Fluid Dynamics: CFD simulation to compare the flow patterns of the three stirring blade concepts under conditions in which the blade was installed at the center of the tank, 2 centimeters above the tank bottom, and operated at rotational speeds of 90, 100, and 110 rpm. Flow velocity, shear stress, and torque were considered together with strength analysis. The analysis results showed that Concept 2 provided the most suitable flow pattern. A prototype was then fabricated and tested in actual production for 10 tanks. The test results showed that the amount of tofu residue remaining at the bottom of each tank was less than 1 kilogram, and the tofu texture met the factory’s standards. Furthermore, the accumulated stirring time was reduced by 102 seconds compared with manual stirring.
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