DESIGN AND GAS FLOW MODELLING OF RADIAL-INFLOW TURBINE USING MEANLINE ANALYSIS METHOD AND CFD SIMULATION (STUDY CASE : 100 KW MICRO GAS TURBINE )

• Main Author: Dzulfiqar Cahyanto, Ivan
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/66763
• Institution: Institut Teknologi Bandung

The micro gas turbine is one of the prime movers used in distributed power plants. As a prime mover in distributed power plants, micro gas turbine have a high value of thermal efficiency in a compact dimension. The design and the flow phenomenon that occurs inside the turbine blade determine the turbine performance. Thus, a good designing process supported by fluid flow analysis is required to produce turbine blade with high isentropic efficiency and sufficient power capacity In this undergraduate thesis, the turbine component of 100 kW micro gas turbine was being designed and being analyzed by using CFD method. The turbine type selected is the radial inflow turbine with the design constraint as follows: Mass flow rate equal to 0.87 kg/s, with value of inlet total temperature and total pressure respectively 1223 K and 4.5 bar with angular velocity of 70000 RPM. From the thermodynamics analysis of air and combustion gas as an ideal gas, it was found that the minimum turbine power capacity to generate 100 kW of electricity is 303.13 kW. From the thermodynamics analysis and mean-line design process, turbine with 13 rotor blades having inlet radius 90.97 mm and equipped with 22 stator blade was designed. From 2-dimensional analysis the turbine predicted to have 319.3 kW power capacity with isentropic efficiency as high as 83.47%. After the geometry parameter was calculated, CFD analysis was being done to study the turbine performance and flow characteristics. The results from CFD simulation shows that the turbine will produce 317.248 kW with 84.29% of isentropic efficiency. Several flow phenomena was detected in CFD simulation which consists of choking in the rotor passage, vortex flow in the pressure and suction side of rotor, and the occurrence of secondary flow at the rotor blades. The results shows that the turbine that has been designed can produce sufficient power, but optimization can be done to acquire higher value of isentropic efficiency