Modelling Creep and Creep-Fatigue Damage for CSEF Power Plant Steels: Taking into Account Variable Ductility (EDF Energy/BF2RA)

The current market conditions are such that combined cycle gas turbine (CCGT) plants are now considering double two-shift operation, so potentially accruing upwards of 600 starts per year. For operators of large generation facilities the key consideration is the through life revenue return. On this basis the need for effective life prediction and condition monitoring tools to support the supply chain (designer, fabricator, operator and technical service provider) is evident.

Over the years, significant development has been made on the 9–12%Cr creep strength enhanced ferritic (CSEF) steels. Traditionally, in material development for power plant components, creep ductility, which can be treated as resistance to damage, has received much less attention. However, the risk of catastrophic failure due to low damage tolerance is a real challenge, in particular, in the situation where mechanical and metallurgical constraints are present. In addition, due to the increasing frequency of cyclic operations, i.e. starts up and shut downs for main steam pipelines of power plants, low cycle creep fatigue failure due to low ductility of the materials has become an important concern.

The aim of the proposed project is to investigate creep and creep fatigue behaviour which takes into account the variable ductility for CSEF power plant steels, through a comprehensive theoretical, experimental and computational programme.

Specific objectives will include:

1. Data acquisition/analysis and critical review on the currently available models and assessment procedure.
2. Experimental/physical understanding of creep and creep fatigue behaviour of CSEF power plant steels with different initial ductility.
3. Development of a novel creep and creep fatigue model which takes into account the variable ductility.
4. Application of the model for component assessment using the operational data from a modern CCGT plant.

High temperature mechanical testing and physical characterization will be carried out using well-established facility. The theoretical and modelling work will be carried out using finite element package ABAQUS through user defined subroutines.

We wish to recruit a graduate with a first or high 2.1 (above 65% grade mark average) class honours degree in an engineering or science discipline (e.g. mechanical engineering or applied mechanics) for this project which starts 1 October 2018. A strong background of Mechanics of Solids and Computational Modelling is preferable. The funding available restricts applications to Home UK students and exceptional International students (limited funding). This project’s industrial partner is EDF Energy/BF2RA. The student will have opportunity to work with experts from EDF (UK) and EPRI (USA). The Industrial Supervisor is Professor Andy Morris at EDF.

Funding Notes
The Engineering Doctorate (EngD) is of four years duration and carries an enhanced annual stipend of £19,277 to eligible UK candidates. Please visit our web site to find out further information on the Centre. View Website: http://www.ccscfe-cdt.ac.uk/

A limited amount of partial funding is available for exceptional international applicants who are highly qualified and motivated. Due to the nature of this funding, the CDT would only be able to cover the cost of the Home UK fees and therefore the applicant would need to find an alternative funding source for the difference between Home and International fees.