DESIGN OF HEAT EXCHANGER FOR ORGANIC RANKINE CYCLE MICROGENERATION SYSTEM WITH 1 KW OUTPUT POWER

• Main Author: Setya Amrullah, Faiz
• Format: Final Project
• Language: Indonesia
• Subjects: Teknik (Rekayasa, enjinering dan kegiatan berkaitan)
• Online Access: https://digilib.itb.ac.id/gdl/view/86332
• Institution: Institut Teknologi Bandung

The need for electrical energy continues to increase as the population increases and the fulfillment of energy needs generally comes from non-renewable energy sources such as fossil fuels whose availability is decreasing and causes an increase in the amount of carbon emissions. Therefore, to support the government's commitment to reduce carbon emissions, alternative energy sources are needed to increase efficiency in energy utilization. One alternative energy that has potential as an energy source to generate electricity is exhaust heat, where currently the utilization of heat wasted in the form of gas from industrial processes and power plants in Indonesia is still not utilized. Exhaust heat generally has low temperature conditions so that it cannot be reused in conventional cycles, so one technology that is suitable for utilizing exhaust heat is the Organic Rankine Cycle (SRO). SRO is one method that is capable of producing a certain amount of electrical energy without requiring high temperatures. The working principle of SRO is the same as the conventional Rankine cycle, but SRO operates using organic fluids. Since one of the important components in the overall efficiency of SRO is the heat exchanger, efforts are made to design a suitable heat exchanger as needed in micro-scale SRO. This undergraduate project will calculate the heat demand for the condenser and evaporator with variations of working fluids R-134a, R-245fa, and R-1233zd. A heat exchanger design suitable for micro-scale SRO using R-134a working fluid with a target output power of 1 kW is also carried out. Based on the analysis results obtained, the heat demand in the condenser and evaporator in the organic working fluid variation is 15.45 kW and 16.35 kW for R-134a with a thermal efficiency of 5.49%, 8.28 kW and 9.24 kW for R-245fa with a thermal efficiency of 10.39%, and 7.96 kW and 8.92 kW for R-1233zd with a thermal efficiency of 10.82%. As for the results of the heat exchanger design geometry for micro-scale SRO using R-134a working fluid, a shell and tube type was chosen which resulted in a geometry for a 1600 mm long condenser with a total of 85 tubes, as well as a 1000 mm long evaporator geometry with a total of 22 tubes.