SIMULATION OF CONTROL AND EXPERIMENT ON TILAPIA POND USING DOUBLE PIPE HEAT EXCHANGER NON CIRCULATION WITH GEOTHERMAL AND AIR TEMPERATURE DISTURBANCE

• Main Author: Romadhona, Muhammad
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/67290
• Institution: Institut Teknologi Bandung

One example of direct geothermal utilization is tilapia cultivation which has an optimum living temperature of 22-30°C. However, in actual conditions, the pool temperature can fluctuate due to several disturbances such as changes in air temperature and geothermal water (brine). Therefore, we need a control system that can keep the pond temperature stable and following the optimum living temperature of tilapia. This study aims to conduct experiments to determine the response of PID control in maintaining the pool temperature according to the setpoint temperature of 26°C. 3 variations are used, namely without using a disturbance, using a disturbance of changes in air temperature, and using a disturbance of changes in the temperature of geothermal water. In addition, this study examines the heat load and the effectiveness of the non-circulating double pipe heat exchanger. Before the experiment, this research was simulated in MATLAB to obtain the value of proportional constant (KP), integral constant (KI), and derivative constant (KD) at geothermal water temperature at 50°C and pool temperature at 26°C. From the MATLAB/Simulink simulation, the values obtained are KP=55, KI=0,0015, KD=0 for geothermal water temperature, and KP=617, KI=0,0011 KD=0 for fishpond water temperature. The experimental results show that when the variation is without disturbance, the pool water temperature is stable at 25.95°C. When the disturbance variation changes the ambient air temperature from 19-23°C, the pool water temperature drops from 25.95°C to 25.75°C. During the disturbance variation, the geothermal temperature changes steady from 50°C to 45°C, and the pool temperature drops from 25.93°C to 25.88°C, but when the geothermal temperature changes from 50°C to 55°C, the pool temperature increases from 25.93°C to 25.95°C. For transient conditions, the order of geothermal temperatures from the fastest to the lowest to make the pool temperature setpoint is 55°C, 50°C, and 45°C. For the heat load generated by the double pipe heat exchanger a maximum of 1100 W while the effectiveness is 0.65. Based on this research, the PID control works well to maintain a temperature of 26°C.