Modares Mechanical Engineering

Modares Mechanical Engineering

Evaluating the effect of inlet angle and leading edge geometry of the blade on the efficiency improvement of the PAT power station

Document Type : Original Article

Authors
Salman Saremian
Mohammad Hasan Shojaeefard
Mechanical Engineering Department, Iran University of Science and Technology, Tehran, Iran
10.48311/mme.2026.121509.83044
Abstract
The significance of enhancing renewable power plant capacity becomes increasingly evident considering the growing energy demand, climate change, and air pollution caused by fossil fuel power plants. Micro-hydro power plants represent a viable option for increasing clean energy capacity in water distribution and transmission networks, though they have historically received less attention due to their high initial costs relative to lower generation capacity. A substantial portion of the power plant cost can be reduced by utilizing pumps and motors in reverse operation mode; however, challenges exist in their implementation. In this study, the performance of a pump as turbine (PAT) was investigated both experimentally and numerically, and a comparison was conducted to validate the numerical solution, with the minimal discrepancy in results confirming the adequate accuracy of the simulations. Due to the fact that pump blade profiles are not designed for reverse operation, significant losses occur, particularly under off-design operating conditions. In this study, the effects of blade leading edge geometry and blade inlet angle were examined to improve performance, and subsequently, the simultaneous modification of these parameters was analyzed numerically. The vorticity analysis results demonstrate improvement in flow fields, reducing flow separation, and vortex formation at the inlet and throughout the entire runner passage, which has resulted in extending the high-efficiency operating range of the PAT. The maximum improvement occurred at a flow rate of 175m³/h, with the efficiency enhanced by 3.2%.
Keywords
Pump as turbine
Rounding leading edge
Blade inlet angle
Vorticity
Energy recovery
Subjects
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Modares Mechanical Engineering
Volume 27, Issue 1
January 2027
Pages 49-63