Ultrasound-Assisted Diagnostics for Assessing the Technical Condition of Ships | Gdańsk University of Technology

A research project led by Prof. Beata Zima from the Faculty of Mechanical Engineering and Ship Technology (FMEST) has received funding under the LIDER program, organized by the National Centre for Research and Development. The research team will develop a methodology and a prototype of a system designed for monitoring the condition of coating structures. This system will find applications in shipbuilding, enabling the assessment of corrosion levels in ship structures.

As emphasized by Prof. Beata Zima, the project leader, the initiative was conceived in response to the needs of the maritime industry. The proposed device is intended to support the work of inspectors responsible for evaluating ship conditions and the extent of corrosion. The invention will reduce the number of required measurements, thereby significantly shortening inspection times.

“Currently, inspectors perform point-based thickness measurements. Depending on the size of the vessel, tens or even hundreds of thousands of such measurements may be necessary. However, these still provide only a rough approximation of the actual thickness reduction caused by corrosion. During this time, the vessel remains in dock and cannot perform its operational tasks. This is why we aim to propose a new measurement method,” explains Prof. Beata Zima from the Institute of Ship Construction, Faculty of Mechanical Engineering and Ship Technology.

The current project builds upon earlier basic research funded by the National Science Centre. The team investigated how mechanical waves propagate through a plate with non-uniform thickness and covered with layers of corrosion products of varying properties. The researchers concluded that it is possible to determine the corrosion level over a larger surface area using a single measurement.

Surface Measurement Using Ultrasound

What does the proposed measurement method entail in practical terms?

“Our method involves emitting an ultrasonic signal, which—much like a stone thrown into water—generates a wave that propagates through the material,” says Prof. Zima. “When the material is undamaged, the waves propagate symmetrically. In a corroded plate, this symmetry becomes disrupted.”

Prof. Zima explains that the propagation of ultrasound across the surface of a coating allows for the characterization of the entire plate rather than just isolated points.

Prototype Development

Prof. Zima and her team are currently working on a project titled “Development of a Methodology and Prototype of a Monitoring System for Evaluating the Condition of Coating Structures.” The project has recently received a grant of 1,744,442.50 PLN under the LIDER program organized by the NCRD. Demonstrating the implementation potential of the project was a necessary requirement for funding, which involved securing support from an industry representative who confirmed the significance of conducting such research.

The prototype device is presently under development. As Prof. Zima explains, the team must account for numerous parameters that affect measurement accuracy to ensure the proposed device yields reliable results.

“The measurement method we propose is based on a form of averaging. We perform fewer measurements, which means we lose some information. It is difficult to precisely reconstruct the exact shape of the plate, but it is feasible to map the thickness distribution in the form of a statistical profile,” explains Prof. Zima. “The area that can be assessed with a single measurement is not infinite. The ultrasonic wave attenuates and eventually dissipates, the process is exacerbated by obstacles it encounters—these may include other structural elements of the vessel, such as bulkheads or frames, as well as the corrosion itself.”

Beyond Corrosion Detection

The project leader emphasizes that the invention has potential applications beyond metal plates affected by corrosion. Ultrasonic waves may also be used to inspect composite structures, such as those employed in yacht construction, which are likewise susceptible to various forms of damage.

The research team led by Prof. Beata Zima includes scientists from Gdańsk University of Technology’s Faculty of Mechanical Engineering and Ship Technology, Faculty of Electronics, Telecommunications and Informatics, as well as researchers from the Institute of Fluid-Flow Machinery of the Polish Academy of Sciences.

The project is funded through the LIDER program, which is run by the National Centre for Research and Development. LIDER is aimed at early-career researchers up to seven years post-PhD. Its objective is to enhance competencies in independently planning research work and managing research teams while conducting projects with practical applicability and implementation potential.