Decarbonising the maritime transport with ammonia

Thermal engines are inarguably the prevalent technology powering the maritime sector worldwide, predominantly with fossil fuels. Solid evidence suggests that such engines will maintain a large share of the market for decades to come. Yet, legislation and environmental concerns mandate the drastic reduction of greenhouse gases (GHG). To this aim, current relevant technology must be decarbonized and replaced by environmentally friendly and financially viable solutions. The introduction of alternative, carbon-free, fuels powering such thermal engines, seems to be the apparent solution in this direction.

Ammonia is considered by many as the most suitable candidate to replace fossil fuels in such thermal engines because: It is carbon-free (i.e., has no direct GHG effect); it can be synthesized from renewable sources; an established, reliable infrastructure already exists for both storage and distribution along with safe handling procedures; it allows efficient engine operation, and; it exhibits much higher energy density than gaseous/liquid hydrogen. In fact, a conventional thermal engine can operate on ammonia with only minor modifications.

The use of ammonia in thermal engines has a long history, with most efforts concentrating on spark ignition (SI) engines or gas turbines and only few on compression ignition (CI) engines, due to ammonia’s low flame speed and high resistance to auto-ignition. Yet, the great benefits of CI against SI engines (i.e., fuel economy, power efficiency, durability and heavy-duty application) fueled with ammonia have largely remained unexplored.

In CI engines, ammonia has been mainly used in dual-fuel configurations with only few studies on pure ammonia operation. The implementation of ammonia in a single-fuel concept has been proven to be challenging due to the extremely high compression ratios required in order to overcome the high auto-ignition temperature. In dual-fuel operation, (where ammonia is used along with an additive which promotes the ignition of the mixture) ammonia has been mainly used with carbon-based fuels, such as diesel, which (in)directly produce carbonaceous emissions (e.g., CO2), thus, cancelling or reducing the efforts for GHG reduction. Limited studies have also been reported with the addition of hydrogen, where a large quantity of hydrogen (at least 30% vol.) were reported to be necessary to maintain stable combustion, and NOx increased significantly.

The objective of the current project will be to perform a multi-level computational comparative investigation on ammonia operation in CI conditions with different (existing or new) ignition promoters and water/EGR for NOx reduction, thus, paving the way for the development of a novel, affordable and environmentally friendly technology for CI maritime engines, in alignment with UK’s plan for zero emissions by 2050. The decarbonisation technology proposed in the current project aspires to combine carbon-neutrality with the simplicity and the high efficiency of the thermal engine.

Academic qualifications 

A first-class honours degree, or a distinction at master level, or equivalent achievements ideally in Mechanical Engineering or Marine Engineering. 

English language requirement 

If your first language is not English, comply with the University requirements for research degree programmes in terms of English language. 

Application process 

Prospective applicants are encouraged to contact the supervisor, Dr Stathis Tingas (E.Tingas@napier.ac.uk) to discuss the content of the project and the fit with their qualifications and skills before preparing an application. 

The application must include:  

Research project outline of 2 pages (list of references excluded). The outline may provide details about 

• Background and motivation, explaining the importance of the project, should be supported also by relevant literature. You can also discuss the applications you expect for the project results. 
• Research questions or 
• Methodology: types of data to be used, approach to data collection, and data analysis methods. 
• List of references 

The outline must be created solely by the applicant. Supervisors can only offer general discussions about the project idea without providing any additional support. 

• Statement no longer than 1 page describing your motivations and fit with the project. 
• Recent and complete curriculum vitae. The curriculum must include a declaration regarding the English language qualifications of the candidate. 
• Supporting documents will have to be submitted by successful candidates. 
• Two academic references (but if you have been out of education for more than three years, you may submit one academic and one professional reference), on the form can be downloaded here. 

Applications can be submitted here.

Download a copy of the project details here.