DESIGN OF AGITATOR FOR COOKING PROCESS OF SOY SAUCE WITH DYNAMIC CHARACTERISTICS CONSIDERATION

• Main Author: HARYANTO (NIM : 23116009), AIDIL
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/25221
• Institution: Institut Teknologi Bandung

<p align="justify"> Soy sauce is one type of dark brown food, distinctive smell, salty or sweet taste, lumpy, and contains protein produced from fermented. One of tool that can be used for cooking soy sauce is a pressure vessel as cooking pan with a agitator. Agitation is the way in which mixing and stirring phases are carried out by heat transfer and mass inter-phases or with external surfaces (due to outside influences). Agitator is a system used for mixing and stirring accompanied by a phase change. Agitator have the purposes such as suspending solid particles, blending liquids, dispersing gases through liquids in the form of small bubbles, and heat transfer between liquids and coils or jackets. <br /> <br /> Agitator design has been done in the process of soy sauce for capacity of 6000 liters per production, agitator rotational speed about 5 RPM, soy sauce viscosity of 1900 cP with an existing pressure vessel design. The designed agitator components consist of shaft, impeller, bearing, speed reducer, and motor. Moreover, to avoid the failure caused by vibration. The frequency of vibration analysis in agitator shaft is designed using rotordynamic prediction or using ANSYS software. The frequency of vibration analysis is performed with rotor in free motion and the four variations of the bearing modeling, ie modeling with one bearing as fixed support at the end of the shaft, modeling with one bearing as roller support at the end of the shaft, modeling with two bearing as fixed support at the end of the shaft and the roller support at the other bearings, and the modeling with two bearing as the roller support on both bearings. <br /> <br /> The type of impeller used is an anchor impeller with a diameter of 2352 mm, width of 193 mm, 20 mm thick and 1344 mm high. The diameter of the shaft is designed sebear 70 mm with length 2360 mm. The power of agitator required is 1.78 kW. The material used is Al alloys 5052-H38. The bearing use SKF standard to support the shaft with tappered roller bearing type is ISO 355 (ABMA) type 2CC. Speed reducer designed using Cyclo BBB catalog standard with model number is LVHJ 3-3C145 L-Y5-305 and motor designed according to Cyclo BBB catalog standard using 3 HP motor with rotational speed 1750 RPM model number LHH 3-3D160-L B-Y5 -305. <br /> <br /> The frequency of vibration analysis using theoretically finite element and ANSYS based on variation of bearing have the same frequency for rotation in the range of 5 RPM. It is still safe according to the mechanical vibration. The designed agitator shaft will be resonance and should be avoided at point A with a rotational speed ± 160 RPM and frequency ± 2.5 Hz, B rotational speed ± 190 RPM and frequency ± 3 Hz, C rotational speed ± 680 RPM and frequency ± 11 Hz, D rotational speed ± 310 RPM and frequency ± 2.5 Hz, E rotary speed ± 430 RPM and frequency ± 3 Hz, and F rotational speed ± 1150 RPM and frequency ± 9 Hz according to Campbell diagram. The highest amplitude caused by respone of unbalanced mass based on the design is found in mode shapes number 4 that is less than 2.5x10-2 mm and can be considered very small effect. <p align="justify">