Master thesis proposal

Being responsible for 3% of the worlds green house gas emissions, the shipping industry needs innovative concepts of propulsion. Using wind as a direct and renewable propulsion force can be realized with large wing-like rigid sails. This technology relies on the old concept of sailing combined with new ways of actuation and automated control. It is still at an early stage and the development of prototypes offers the chance of exploring their potential in real life. A profound experimental analysis of the governing physics, especially the flow responsible for generating the aerodynamic propulsion force, can lead to practical knowledge for further improvement in control and the advanced design of future wing sails.

This thesis project is concerned with the development and testing of a sensor array, enabling the study of surface pressures on a model prototype with the possibility of deployment on a full-scale prototype. Sensing surface pressure distributed over the wing sail profile surface allows for a quantitative analysis of how the generated aerodynamic force is distributed over the sail.

An example pressure distribution is shown in below image. Sensors could be placed along a 2D section as indicated with black markers. By integrating numerically over the profile, a 2D force contribution can be derived. If the same is done at several locations along the span, a second numerical integration can give a total force estimate.

The thesis work includes the design of such a sensor array including the development of electrical integration and software. Tests in appropriate mechanical realizations should be performed to verify the system.

The specific objectives of this thesis are:

• To perform a literature review on methods of measuring surface pressure in practical applications outside lab environments
• To design a sensor array suitable for installation on a full-scale wingsail prototype and solve the electrical integration of the sensors

• To develop software that can be used to evaluate the sensor array with respect to accuracy and real-time performance
• To develop software that processes the pressure distribution over the wingsail to determine and estimate of the aerodynamic forces, the center of aerodynamic effort and the distribution of inflow angles over the wing span
• To run experiments on a model prototype for verification including an evaluation if the accuracy and frequencies of the sensor system are high enough to give a good representation of the total aerodynamic forces acting on the airfoil

The main deliverable of this work include but are not limited to:

• Design and technical specifications of the developed sensor array
• Test results
• Final thesis report and presentation of the project

The project should start from April 2024 or later with a duration of up to 6 months.

If you are interested in this opportunity and want to learn more, please contact Antonia Hillenbrand, Development Engineer & Industrial PhD Student (KTH), Oceanbird, at antonia.hillenbrand@theoceanbird.com.