Nanoscale Coating System to Improve Efficiency and Durability of Hydraulic Turbines

Cavitation and particle erosion in hydraulic turbines present unwanted consequences such as flow instabilities, excessive vibrations, damage to material surfaces, degradation of equipment performance, and inefficient energy generation. These problems are becoming more critical because the propensity for cavitation and erosion is being enhanced. Furthermore, environmental problems result from degradation of turbine components by creating sharp and rough edges that can cause serious injury or death to migrating fish. Determining the effectiveness of advanced coatings towards minimizing the negative effects of cavitation and particle erosion and how that relates to durability and efficiency of turbine components is an important step if hydropower is to realize its full potential as a renewable energy source. NEI Corporation proposes to demonstrate the application of a multifunctional two-layer nanocomposite coating system to enhance hydraulic turbine efficiency, durability and fish safety. The premise of the proposed work is that a hybrid nanocomposite coating applied to hydraulic turbine components will provide cavitation and erosion resistance, smooth surfaces, and a low coefficient of friction. The size of the worldwide steam and hydraulic turbine market is about $10 billion based on product demand. The US accounts for ~$450 million of that figure and is expected to grow to $520 million over the next six years. NEIs advanced coating system will be applicable to various turbine components in new and refurbished installations. These coatings will improve the overall efficiency of turbines through reduction of friction, and also improve the environmental performance of turbines by reducing injury to fish that come into contact with coated surfaces. Advances may also be made in lowering application cost, improving durability, and reducing maintenance costs for coated surfaces thus further enabling hydropower as a renewable energy source.