DESIGN OF RADIAL INFLOW TURBINE FOR 1 KW ORGANIC RANKINE CYCLE SYSTEM USING R-245FA AS WORKING FLUID

• Main Author: Bonar, Asybel
• Format: Theses
• Language: Indonesia
• Subjects: Teknik (Rekayasa, enjinering dan kegiatan berkaitan)
• Online Access: https://digilib.itb.ac.id/gdl/view/52300
• Institution: Institut Teknologi Bandung

Organic Rankine Cycle (ORC) is a reliable technology to utilize low and medium thermal energy and has been on development since beginning of 19th century and has rapid development since last few decades. There are couple of ways to optimize ORC, and one of them is to develop an optimized turboexpander. This thesis will explain in detail the preliminary and detailed design approached used to design turboexpander for 1 kW ORC with R-245fa as working fluid. The initial mass flow of working fluid used is 0,3 kg/s with Inlet pressure of 730 kPa and Outlet of 560 kPa. The inlet temperature of working fluid is 368,87 K. The designed geometry was transformed into 3D model using CAD software. The numerical simulation was performed using ANSYS CFX with SST K-? turbulence model, and Aungier Redlich-Kwong Equation of state to predict the material properties. CFD result shown that highest specific power output produced at 16 blades with 20.000 rpm for 998,54 Watt with total to total isentropic efficiency of 78,54%. The initial designed configuration was not able to obtain the minimum requirement of 1 kW power generation, thus further analysis using different configuration were needed. The further analysis showing that the highest efficiency achieved with the configuration of 0,32 kg/s of working fluid mass flow, 16 rotor blade, and rotation speed of 20.000 rpm. The off design parameter of designed turbine produced power of 1.382,3 W with total to total isentropic efficiency of 76,44%. The thesis will also discuss the possible method to produce designed turbine, material, and additional component used. The designed turbine will use BLDC motor to replace permanent magnet generator as the generator for 1 kW and 20.000 rpm is hard to obtain in the market. A replica with 1:1 scale was produced using PLA as material for 3D printing.