H2 hydrogen

Hydrogen has long been envisioned as the energy carrier to replace carbon-based fuels, but without significant breakthroughs its application in internal combustion engines has stayed at research level. A boom in research has surged within the recent years as the world desperately searches low-emission alternatives to traditional maritime fuels. This work defines a framework for a prototype hydrogen engine that will be built in later phases of the project. Literature and research papers were examined to discover established hydrogen solutions for internal combustion engines. The gained knowledge is used as a framework on how to retrofit an existing engine to allow the use of hydrogen as the main fuel instead of natural gas. In engine parts where retrofitting is not possible, new solutions are presented. Both the advantages and disadvantages of hydrogen are considered. Thus, the hydrogen engine specifications and auxiliary system requirements were established. As the first step in retrofitting an existing engine to be hydrogen driven, a framework of engine requirements was achieved. Following this work, the hydrogen engine components will be further defined to develop and test a working hydrogen engine prototype.

In WP3, the deliverable D3.3 report describes the development of hydrogen engine for CHEK Cruise concept. The report investigates spark-ignited four stroke medium bore single cylinder gas engine of W31SGSCE and discusses the selected components and control systems for hydrogen fuel combustion. The components include the fuel supply system, cylinder head unit, turbocharger, exhaust aftertreatment catalyst, and control system.

The first prototype hydrogen engine was tested at Wärtsilä laboratory as described in deliverable D3.6 report. Two sets of test campaigns have been performed focusing on power output, emission levels and engine efficiency. In the first set of test campaign, pure hydrogen fuel was used on “W31SG engine as it is”, without any hardware modifications. The target is to gain robust understanding of standard engine performance. In the second set of test campaign, the pre-combustion chamber was replaced with poppet valve concept. This was due to better injection timing control compared to conventional low-pressure gas engine main gas admission valve technology. The tests revealed challenges such as backfire, pre-ignition, and knocking. The report concludes that further design modifications are needed for the engine to run on pure hydrogen fuel. Wärtsilä plans to continue testing and aims to have a pure hydrogen engine available by 2025.

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This work discusses the most relevant rules and regulations to date that must be regarded when developing a hydrogen fuel system intended for an internal combustion engine. A literature review was done based on several standards, rules, regulations and scientific journal papers including e.g. IGC and IGF codes and rules of hydrogen fuel cell installations.

An essential part of the work was to recognise the aspects of designing a safe marine hydrogen fuel system. This included evaluation of storage tank, pressure regulation system, piping system and safety aspects including gas detectors and ventilation aspects. The work continues and a prototype hydrogen fuel system will be designed during the CHEK project.

A comprehensive guide on building a land-based hydrogen fuel system is presented. The guide consists of 31 different tasks to be undertaken before safe commissioning of the fuel system. In addition to providing hydrogen for internal combustion engines, the system is designed to flexibly provide fuel for Proton Exchange Membrane (PEM) fuel cells.

The dimensioning of the fuel system is thoroughly considered. Due to the different locations for the hydrogen engine and the fuel system, items that require attention for integrating them together are discussed. The hydrogen engine prototype has been tested and its development continues.