Flexibility of Turbines

About

Existing hydraulic turbines have certain limitation when it comes to accommodate the intermittent power generated using wind and solar energy. Increased intermittency and deregulation of the energy market have pushed the hydraulic turbines to the extreme limit.

Traditionally, the hydraulic turbines are designed for very few start-stop cycles during their lifetime. To accommodate the variable energy demand and to maintain the robustness of the power grid, a novel design approach is needed that helps to develop the next generation of hydraulic turbines.

Activities under this work package aim to develop a variable-speed Francis turbine that accommodates high ramping rates and up to 30 start-stops per day.

Objectives

Work package 3 has the following objectives:

• Develop a new hydraulic design of a variable speed Francis turbine based on analytical and empirical knowledge
• Numerical optimization of the new hydraulic design of a variable speed Francis turbine, which aims for a prototype turbine efficiency above 95% and a technical lifetime of 50 years
• Turbine performance tests in the laboratory
• Develop a software for turbine lifetime estimation

Tasks

3.1. Development of a design tool for variable speed Francis turbines

This task aims to produce the hydraulic and mechanical design of the Francis turbine. The new turbine design will focus on the geometry of the guide vanes, runner and a new type of guide vanes in the draft tube. The design parameters will be programmed in to a design tool where the parametric design study can be carried out.

3.2. Numerical analysis to investigate the flow field and stresses in the turbine

In this task, a process for a multi-parametric turbine design will be developed. The process will combine the design tool from Task 3.1 with the available numerical tools that are found in the software package from Ansys. The criteria for optimization will include the turbine efficiency and its characteristic hill chart geometry.

3.3. Validation of the turbine design through model turbine experiments

This task aims to verify the Francis turbine design through experimental investigation of the hydraulic and mechanical performance. The experimental investigation will consist of efficiency-, velocity, – pressure- and strain-measurements of the Francis model turbine.

3.4. Develop a model for turbine lifetime estimation

This tasks aims to develop a calculation tool that estimates the expected lifetime of a new turbine runner. The tool will help the manufacturers to improve the structural design of the runners, and help the power companies to improve their production and maintenance planning.

Participants

WP 3 is led by the Department of Energy and Process Engineering, NTNU.

Contact: Dr. Igor Iliev

Partners:

• NTNU (Leading task 3.1 and 3.3)
• EDR (Leading task 3.2)
• Rainpower (Leading task 3.4)
• UKiM
• LTU