Effect of the roughness and the twisted angle on the blade thermal efficiency for low pressure impulse steam turbine

A lot of attempts have been made to enhance blade thermal efficiency. The low-pressure stage in the steam turbine is very important in a power plant. There are many parameters affected by the efficiency (speed, temperature, pressure, roughness, inlet blade angle, etc.). In this paper, the roughness and twisted blade angle were investigated numerically using ANSYS CFX 2020 R2 to find their effect on efficiency. The values of the roughness coefficient had been selected as 0.8, 0.85, 0.87, 0.9, and 0.95, with twisted blade angles are (3⁰, 6⁰, 9⁰,12⁰and15⁰). The findings showed that the roughness and the twisted angle of the blade have a significant impact on thermal efficiency and are proportional to thermal efficiency.