STEADY NUMERICAL SIMULATION OF FRANCIS TURBINE OPERATION UNDER LOAD VARIATIONS

• Main Author: Laras Narottomo, Alam
• Format: Final Project
• Language: Indonesia
• Subjects: Teknik (Rekayasa, enjinering dan kegiatan berkaitan)
• Online Access: https://digilib.itb.ac.id/gdl/view/79113
• Institution: Institut Teknologi Bandung

The Indonesian government plans to increase New and Renewable Energy (EBT) electricity generation capacity by 35 GW in the 2021-2030 period to accelerate Net Zero Emissions target by 2060. Many EBT power plants are intermittent and hydropower could be an option to maintain power system reliability. The Cirata PLTA is electricity plant that has basic function as base loader of system reliability with flexible operating conditions, so the Cirata PLTA must be able to produce output power that varies according to system supply needs. In this undergraduate thesis, numerical modeling and simulation of the Francis runner of Cirata I was carried out under partial load to overload operating conditions, namely at operating loads above 65 MW or 50% of the rated output. General specification data was obtained from Cirata I runner data, then the turbine geometry was modeled using 3D Computer Aided Design (3D CAD) software. At the numerical simulation stage, meshing creation, boundary condition, simulation model, and iterative calculations are carried out respectively with Computational Fluid Dynamics (CFD) software. The numerical simulation results show 5.33% mass flow rate error compared to commissioning test data and 1.52% best efficiency error for the Cirata I specification data, so that the numerical simulation can describe the actual operating conditions of the turbine. The maximum efficiency from the simulation results is 91.54% and the characteristics of part load to overload can be determined. The phenomena that occurred include indications of reverse flow, cavitation, flow separation and channel vortex.