Numerical Solutions for Prediction of Nozzle Loss Factor and Flow Coefficient of 1.5 Stage Axial Gas Turbine Utilizing Waste Heat from Marine Diesel Engine

Main engine exhaust gas energy is by far the most appealing among the waste heat sources of marine diesel engines in ships in light of the heat flow and temperature. It is feasible to produce electrical power output using this exhaust gas energy in a waste heat recovery system containing power turbines and steam turbines (some portion of exhaust gas heat is used for creating steam). The essential wellspring of waste heat of the primary motor is the exhaust gas heat dissipation, which represents about portion of the complete waste hotness, for example around 25% of the total fuel energy. In the present study, a 1.5 stage axial turbine (with the turbine rotor interspaced between two stators) utilizing waste heat from the marine diesel engine is considered for investigating performance using ANSYS CFX. Simulations are carried out with rotor speed varying from 1000 RPM to 8000 RPM with turbine inlet pressure kept constant at 4 bar. The performance of axial gas turbine is analyzed with inlet temperatures varying from 523 K to 673 K for different mass flow rates and rotor speeds The Flow coefficient of the rotor is also found to be within the acceptable range between 0.5 to 1.1 and is observed to cut the efficiency line between 2800 RPM and 4000 RPM, corresponding to 70% to 78% efficiency. Nozzle Loss Coefficient (NLC) represents the deviation of the actual process with the isentropic process in a stator blade of the turbine.