DESIGN OF RADIAL INFLOW TURBINE FOR BINARY CYCLE IN LAHENDONG GEOTHERMAL POWER PLANT

• Main Author: GOZALY (NIM : 23110030); Tim Pembimbing : Prof. Dr. Ir. Aryadi Suwono; Dr. Ir. Ari D. Pasek; , JOAN
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/16177
• Institution: Institut Teknologi Bandung

Binary cycle is a cycle in geothermal power plant that uses organic fluid as a working fluid that is heated and evaporated by brine. In binary cycle, turbine is a component that converts energy content in the steam into shaft kinetic energy then rotates a generator to produce electricity. Literature study done by the author showed that a radial inflow turbine type can be used in Lahendong geothermal power plant. Nowadays, this turbine type is being developed because of its higher efficiency compared to axial turbine’s. Calculation done by the author shows that by using normal-pentane as a working fluid, it is necessary to use two radial inflow turbines to accommodate <br /> <br /> <br /> power generation in the binary cycle Lahendong geothermal power plant. In this thesis, a design of volute, nozzle, and rotor for first turbine has been done, while the design of the second turbine is beyond the scope of this thesis. <br /> <br /> <br /> This thesis considers the algorithm for designing volute, nozzle, and rotor components in radial inflow turbine in more structured and simple way and also can be done easier but still needs to refer to literatures. Mostly, iterative methods were used in calculating equations to find the design parameters that are used in forming design drawings. Examples of iterative methods can be found in calculation of inlet and outlet rotor working condition, the quasi-normal lines drawing, and calculation of volute inlet radius. Other parameters like blade thickness coefficient, hub radius coefficient, and shroud radius coefficient can be choosen arbitrary, but their influences to turbine’s performance are not considered in this thesis. After all calculations are completed, CAD drawings for volute, nozzle, and rotor components can be generated. <br /> <br /> <br /> This thesis also considered a CFD simulation of the rotor design by means of GAMBIT and FLUENT as CFD software (simulation on volute and rotor were not carried out). The rotor simulation did not give a good result because of the limitation of compressible fluid model available in the FLUENT software, which limited to an ideal gas model. Ideal gas model is not applicable for this case because the binary cycle uses saturated fluid in the turbine’s inlet condition with its properties (especially density) are extremely different compared to ideal gas properties. The simulation also showed that values of attack angle in rotor inlet side is reversely proportional to power generated by the turbine. The angular velocity of the shaft is also reversely proportional to power generated by the turbine.