Making waves in hydrodynamic research

Exciting research by IMarEST Benelux member Lode Huijgens is helping to pave the way for the next generation of ship propulsion systems. Marine Professional finds out more.

Each month we feature IMarEST members doing some exceptional and ground-breaking work. This month we profile one of our newer members, Lode Huijgens.

Lode is a member of the IMarEST Benelux branch. He is completing a PhD at Delft University of Technology in the Netherlands, where he has been researching a novel combination of marine simulations, mechatronics and hydromechanics over the last four years.

With an MSc in Marine Technology, Lode has been recognised for outstanding research into technologies to reduce emissions on Dutch-built Sigma class warships. He was also a cadet in the Dutch Merchant Navy School.

His current research into the complex, dynamic interaction between ship propulsion systems, propellers, and waves, could influence new technologies and ship designs as shipping moves towards a lower-emissions future. Marine Professional asked him to explain more.

Tell us about the research you’re doing

We’re carrying out scale model experiments to emulate the interaction between ship propulsion systems and their environment.  

We simulate sea conditions with a wave maker in the towing tank at Delft University and use a scale model propeller powered by an electric motor to represent the ship’s propulsion system. 

These types of experiments with model scale propellers, often referred to as open water experiments, aren’t new, it’s true.  However, they greatly simplify the ship’s propulsion system, especially when testing in dynamic conditions such as waves, and this is where we offer a substantial improvement.  

In our open water set-up, the electric motor is controlled by a powerful simulation computer running a simulation model of a ship propulsion engine. In combination with a number of novel correction algorithms, this model introduces correctly scaled shaft dynamics at model scale.  

Combining hardware and software in a single experiment is generally referred to as Hardware In the Loop (HIL). The submerged hardware was purpose-designed by MARIN in the Netherlands and is state-of-the-art hydrodynamic experimentation technology.

The resulting HIL open water set-up is a world-class tool for marine engineering research which lets us mimic the complex interaction between ship propulsion systems, propellers, and their environment, whilst maintaining dynamic similarity.

So we can, for example, investigate how the dynamics introduced by the environment – waves and ship motions – interact with the machinery and its control systems. It really does give us new insights.

One of the tests in our YouTube video shows how it works.

Are there other uses for your research?

HIL open water experiments open up a wide range of research directions other than propeller ventilation. They can be used to research and demonstrate the performance of advanced sensors and estimators, control strategies, and new propulsion system components, and more. 

Then there are novel low-emission, future propulsion systems based on spark ignition engines and fuel cells: apart from issues related to cost and energy storage, there is still a great deal of uncertainty regarding the dynamic performance of such systems.

The HIL open water set-up also allows us to investigate and demonstrate the safety and efficiency of carbon-neutral propulsion technologies. We can predict how machinery in the engine room will work in realistic circumstances, so it’s a new way to de-risk the steps from desktop simulation to full scale application.

When will your research influence ship design and technology?

I hope these insights will start to feed into new technologies and ship design in the next 1-2 years. As we move towards renewables, they can accelerate the understanding, acceptance, and uptake of the new ship propulsion technologies that we need.

If you’d like to find out more, you can contact Lode on LinkedIn.