Project No: FE0011796
Performer: Purdue University


Contacts

Duration
Award Date:  10/01/2013
Project Date:  09/30/2016

Cost
DOE Share: $500,000.00
Performer Share: $160,557.00
Total Award Value: $660,557.00

Performer website: Purdue University - http://www.purdue.edu/

Advanced Energy Systems - Hydrogen Turbines

New Mechanistic Models of Creep-Fatigue Interactions for Gas Turbine Components

Project Description

The objective of this project is to develop novel tools to predict creep-fatigue crack growth in nickel-based gas turbine alloys for stationary power applications by employing a framework of irreversible cohesive zone models (ICZM) together with a viscoplastic strain gradient (VPSG) continuum formulation. The present work investigates alloy IN 718. The ultimate goal is to create and validate a robust, multi-scale, mechanism-based model that quantitatively predicts creep-fatigue crack growth and failure in nickel-based gas turbine alloy IN 718. A successful model could be embedded into standard finite element software as an add-on analysis tool for gas turbine designers and thus greatly improve their capability to design safe gas turbines without excessive and costly over-design or unsafe under-design.


Program Background and Project Benefits

Turbines convert heat energy to mechanical energy by expanding a hot, compressed working fluid through a series of airfoils. Combustion turbines compress air, mix and combust it with a fuel (natural gas, coal-derived synthesis gas [syngas], or hydrogen), and then expand the combustion gases through the airfoils. Expansion turbines expand a working fluid like steam or supercritical carbon dioxide (CO2) that has been heated in a heat exchanger by an external heat source. These two types of turbines are used in conjunction to form a combined cycle— with heat from the combustion gases used as the heat source for the working fluid— improving efficiency and reducing emissions. If oxygen is used for combustion in place of air, then the combustion gases consist mostly of carbon dioxide (CO2) and water, and the CO2 can be easily separated and sent to storage or used for Enhanced Oil Recovery (EOR). Alternatively, the CO2/steam combustion gases can be expanded directly in an oxy-fuel turbine. Turbines are the backbone of power generation in the US, and the diverse power cycles containing turbines provide a variety of electricity generation options for fossil derived fuels. The efficiency of combustion turbines has steadily increased as advanced technologies have provided manufacturers with the ability to produce highly advanced turbines that operate at very high temperatures. The Advanced Turbines program is developing technologies in four key areas that will accelerate turbine performance, efficiency, and cost effectiveness beyond current state-of-the-art and provide tangible benefits to the public in the form of lower cost of electricity (COE), reduced emissions of criteria pollutants, and carbon capture options. The Key Technology areas for the Advanced Hydrogen Turbines Program are: (1) Hydrogen Turbines, (2) Supercritical CO2 Power Cycles, (3) Oxy-Fueled Turbines, and (4) Advanced Steam Turbines.

Hydrogen turbine technology research is being conducted with the goal of producing reliable, affordable, and environmentally friendly electric power in response to the Nation's increasing energy challenges. NETL is leading the research, development, and demonstration of technologies to achieve power production from high hydrogen content (HHC) fuels derived from coal that is clean, efficient, and cost-effective; minimize carbon dioxide (CO2) emissions; and help maintain the Nation's leadership in the export of gas turbine equipment. These goals are being met by developing the most advanced technology in the areas of materials, cooling, heat transfer, manufacturing, aerodynamics, and machine design. Success in these areas will allow machines to be designed that have higher efficiencies and power output with lower emissions and lower cost.

Purdue University and Oregon State University will work together to create and validate a robust, multi-scale, mechanism-based model that quantitatively predicts creep-fatigue crack growth and failure in the nickel-based gas turbine alloy IN 718. This alloy is representative of materials used in turbine disks, and the creep-fatigue mechanisms of this alloy will be explicitly incorporated into the model. A successful model could be embedded into standard finite element software as an add-on analysis tool for gas turbine designers and thus greatly improve their capability to design safe gas turbines without excessive and costly over-design or unsafe under-design. Incorporation of this new model into existing product life cycle management approaches at NETL has significant potential to reduce turbine manufacturing costs and maintenance costs through increased blade life, leading to lower plant costs and lower electricity costs for consumers.