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Modern marine power plants have been designed to improve the overall ship’s efficiency. This pushed the designers of marine machinery to search for unconventional fuels for these plants. During the previous years, diesel oil has been extensively used on-board ships. Due to the high price of light diesel oil and the environmental problems resulting from the use of heavy fuel oil, it has become necessary to search for an alternative to traditional fuels. As a result, natural gas fuel has been used on-board some types of ships, especially short-voyage cruise ships. Unfortunately, there are still some technical and logistic problems related to the use of natural gas as a fuel, especially as it is considered a non-renewable energy source. The use of hydrogen fuel on-board ships, particularly in modern power plants may contribute to overcoming the above problems. The present paper considers the possibility of the use of hydrogen fuel for marine applications and discusses different stages of hydrogen gas cycle beginning with hydrogen generation process from clean energy until using it as fuel for internal combustion engines on-board one RO/RO ship, named Taba, operating in the Mediterranean Sea. Compared to the diesel engine, the hydrogen fuelled engine is found to be lower in thermal efficiency and fuel consumption, however, some adjustments are needed
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Brodogradnja/Shipbilding Volume 66 Number 1, 2015
Ibrahim S. Seddiek,
Mohamed M. Elgohary
Nader R. Ammar
ISSN 0007-215X
eISSN 1845-5859
THE HYDROGEN-FUELLED INTERNAL COMBUSTION ENGINES
FOR MARINE APPLICATIONS WITH A CASE STUDY
UDC 629.5.026:662.769.2
Review paper
Summary
Modern marine power plants have been designed to improve the overall ship’s
efficiency. This pushed the designers of marine machinery to search for unconventional fuels
for these plants. During the previous years, diesel oil has been extensively used on-board
ships. Due to the high price of light diesel oil and the environmental problems resulting from
the use of heavy fuel oil, it has become necessary to search for an alternative to traditional
fuels. As a result, natural gas fuel has been used on-board some types of ships, especially
short-voyage cruise ships. Unfortunately, there are still some technical and logistic problems
related to the use of natural gas as a fuel, especially as it is considered a non-renewable
energy source. The use of hydrogen fuel on-board ships, particularly in modern power plants
may contribute to overcoming the above problems. The present paper considers the possibility
of the use of hydrogen fuel for marine applications and discusses different stages of hydrogen
gas cycle beginning with hydrogen generation process from clean energy until using it as fuel
for internal combustion engines on-board one RO/RO ship, named Taba, operating in the
Mediterranean Sea. Compared to the diesel engine, the hydrogen fuelled engine is found to be
lower in thermal efficiency and fuel consumption, however, some adjustments are needed.
Key words: alternative fuels; hydrogen engine; hydrogen storage; ship’s emissions
1. Introduction
Marine fuel plays a key role in operation of power plants onboard ships. The latest
years have seen difficult challenges against the use of fossil fuels in marine applications due
to the environmental damage caused by these fuels. That pushed the International Maritime
Organization (IMO) to issue a number of regulations to reduce this effect [1]. Thus, in 2005
the amendments to the Marine Pollution Convention (MARPOL) were issued, i.e. Annex Six
of MARPOL, to reduce air pollution from ships. The requirements of Annex Six establish
limits on ship emissions. Some of these limits concern the permissible percentage of fuel
elements content such as sulphur content [2] while some refer to the percentage of harmful
Ibrahim Seddiek, Mohamed Elgohary, The hydrogen-fuelled internal combustion engine
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24
pollutants emitted from ships such as nitrogen oxides [3]. These regulations pressed all
interested in the maritime field to consider potential alternatives to reduce dependence on
fossil fuels [4-6] and search for alternative types of fuels [7]. Thus, many researchers studied
the possibility of using some of alternative fuels, mostly liquefied natural gas [8-10].
Moreover, other researches pointed out the feasibility of using other types of alternative fuels
such as methanol [11] and hydrogen (GH2) [12] for special marine application. On the other
hand, it was shown by Banawan, et.al [13] that the main obstacles facing the reliance on
marine alternative fuels are: availability, cost, reliability, safety and the compliance with IMO
regulations. Among alternative fuels, hydrogen is considered to be more environmental
friendly and renewable. Despite the safety risks of using hydrogen gas onboard ships, several
researches proved the possibility of using it especially for power generation produced by fuel
cells [14]. The problem arising now is searching for marine alternative fuels that can be
produced through clean energy in order to prevent any further environmental damage caused
by production process. The present paper considers the various steps of using hydrogen as an
alternative marine fuel, including its production, storage, fuel system, and finally its
application in internal combustion engines which represent more than 95% of marine power
plants onboard ships. Also, the paper presents a brief introduction to solving the first step of
calculations in the problem of Hydrogen Internal Combustion Engines (HICE) designing. A
computer model, Engineering Equation Solver (EES) software [15], is used in solving the
problem of designing the marine hydrogen engine. Hydrogen gas turbine design can be
benefited by using the advantages of the computer programs; which was illustrated in authors
previous work [16-17].
2. Hydrogen production
Hydrogen can be produced from a number of sources both renewable and non-
renewable by various processes. At present, a large amount of hydrogen is produced by
reforming of hydrocarbons. However, in order to minimize the reliance on conventional fuels,
considerable developments in other GH2 production technologies from renewable resources
have been made [18]. The following sections give a short description of hydrogen production
methods with emphasis on hydrogen production from clean energy sources.
2.1 Hydrogen from fossil fuels
This method depends on converting the hydrogen-containing materials derived from
fossil fuels into a hydrogen-rich gas. Fuel processing of methane is considered to be the most
common commercial hydrogen production technology today. By this method hydrogen gas
can be produced through three basic technologies: partial oxidation, auto thermal reforming
and steam reforming [19]. A major drawback of these technologies is that they produce a
huge amount of carbon monoxide (CO). Consequently, additional steps to remove CO are
needed. The process of production follows the following equations:
CH4 + H2O + heat
CO + 3H2 (1)
CO + H2O
CO2 + H2 + heat (2)
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2.2 Hydrogen from renewable sources
Hydrogen could be also produced by other methods than reforming of fossil fuels,
including biomass, pyrolysis, aqueous phase reforming, water electrolysis, photoelectrolysis,
and thermochemical water splitting [20].
2.2.1 Hydrogen from solar energy
Solar energy can be used as a source of energy to achieve hydrogen production
through water electrolysis, photoelectrolysis, and thermochemical water splitting process [21].
Choice of solar energy for this purpose is the matter of environmental effect [22]. Among the
previously mentioned technologies, the solar thermo chemical process is better from the
viewpoint of production rate and environmental effect. For example, in traditional thermo-
chemical technology, fossil fuels are combusted with air, which emits not only green house
gases but also gases that contribute on the ozone layer depletion and acid rains. On the other
hand, the solar thermo chemical technology offers either zero or low hazardous gas emissions
[23].
As the main purpose of the present research is searching for environmental friendly
marine fuel, the emphasis of the paper is on the production of hydrogen using solar energy as
renewable source. Figure 1 presents a schematic diagram of solar thermo chemical production
of hydrogen using fossil fuels and water (H2O) as chemical source, including: solar cracking,
solar reforming and gasification.
Figure 1 Clean hydrogen fuel production
Ibrahim Seddiek, Mohamed Elgohary, The hydrogen-fuelled internal combustion engine
Nader Ammar for marine applications with a case study
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3. Storage of hydrogen
Hydrogen is an extremely difficult gas to store, this will limit its use until convenient
and cost effective storage technologies can be developed and commercialized. One gram of
hydrogen gas, for instance, occupies about 12 litres of space at atmospheric pressure. In order
to be more convenient, GH2 must be pressurized under a high atmospheric pressure, and
stored in a pressure vessel. In liquid form, hydrogen can only be stored under cryogenic
temperatures.
Only the two major problems pending for solutions may make the full application of
hydrogen fuel not achievable in the near future: hydrogen storage and production cost.
Liquefied hydrogen has a density of 70.1 kg/m3, which is a very small value if compared to
ordinary liquid fuels with densities in the range from 840 to 1010 kg/m3 [24-25], taking into
account that liquid hydrogen heating value is about 3.3 times higher than that for diesel fuel.
The production cost cannot be accurately determined since the hydrogen fuel is not produced
on a mass production basis. Also, for the two major processes of hydrogen extracting, the
water electrolysis and the steam reformation of natural gas; the production process will be
more expensive than the ordinary fossil fuels. The cost of removing carbon dioxide (CO2),
resulting from the natural gas steam reformation, increases the cost of the ‘fossil’ hydrogen
option. Moreover, cost of hydrogen production by electrolysis is about three times higher than
that produced by steam reforming of natural gas.
3.1 Options of hydrogen storage for marine use
Hydrogen storage is considered to be one of the main obstacles against adopting
hydrogen as fuel onboard ships due to its very low energy and due to safety issues [26]. In
this section, storage alternatives, which include compressed gas, liquefied gas and metal
hydrides, are discussed in order to decide which of them will be suitable for marine use. Also,
the transportation is discussed with special reference to the liquefied hydrogen (LH2) carriers
under development.
3.1.1 Compressed hydrogen storage
Compressed hydrogen in hydrogen tanks under pressure of 350 bar to 700 bar is used
for hydrogen tank systems in vehicles [27]. Storing of hydrogen in form of compressed gas is
the simplest storage method. It needs a few devices such as a compressor and a pressure tank.
On the other hand, the drawback of this method is low storage density, which depends on the
storage pressure.
As the storage pressure increase, capital and operating costs will increase. It is
important to know that when compared with traditional fuels, the energy in a compressed
hydrogen tank is very low for the same tank volume density. Regarding the economics of this
type of storage, both capital and operating costs must be well studied.
The hydrogen-fueled internal combustion Ibrahim Seddiek, Mohamed Elgohary,
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3.1.2 Liquefied hydrogen storage
Liquefied hydrogen storage refers to the storage of hydrogen in the liquid state by
cooling of hydrogen vapour to the cryogenic temperatures of –253 °C. In addition, it can be
stored as a constituent in other liquids, such as NaBH4 solutions, rechargeable organic liquids,
or anhydrous ammonia NH3 [28]. By this method, the weight of hydrogen can be increased by
approximately 20 times compared to the compressed form for the same volume [29].
3.1.3 Metal hydride hydrogen storage
Storage of hydrogen in metal hydrides can be achieved through bonding the hydrogen
to the surface of metal. Metal hydride hydrogen storage has the following advantages: high
hydrogen energy density volumetric capacity, low pressures and low temperatures [30]. The
safety of this method is exciting since no leakage is possible if the tank is broken or fractured
due to accidents and hydrogen is not released unless heat is provided to break the bonds with
the metal. Nevertheless, hydrogen absorption using metal hydrides, chemical hydrides and
carbon systems, requires further development and evaluation [31].
There are some factors which play a role when deciding which method of storage
might be adopted, including: the required energy density, the amount to be stored, the desired
storage period, and the acceptable cost limit. By analyzing the three main systems, the
following conclusions can be made: liquid storage large hydrogen quantities can be stored,
long-term storage if permanent cooling is applied, and low electricity costs for liquefaction;
compressed storage small storage quantities, and short storage time; a hydrogen gas tank
that contains a store of energy equivalent to a traditional fuel tank would be more than 3,000
times bigger. Of course, this value varies with the pressure, but as already mentioned, higher
pressure means higher cost [32].
For marine use, where large quantities of fuel in addition to long storage time are
needed, the storage of hydrogen in the liquid state may appear as the best storage form.
Although liquid hydrogen can provide a lot of advantages, its uses may be restricted because
liquefying hydrogen by existing conventional methods consumes a large amount of heat.
Practically, compressed hydrogen storage has short filling time and long storage time, while a
liquid hydrogen tank has short filling time and short storage time. Moreover, during the long
period of storage, to minimize and control the boil-off losses, the permanent cooling using
another medium such as liquid nitrogen is needed, which requires additional costs [33].
4. Hydrogen bunkering process & regulations
The best way of the hydrogen fuel bunkering process will be in the form of liquefied
gas. Liquefied hydrogen (LH2) will be stored in cryogenic tanks at the temperature of 20 K
and the amount of bunker fuel will depend mainly on the ship’s sailing time and engines
specific fuel consumption. Figure 2 shows the principle components of hydrogen fuel
bunkering either onshore or onboard ships. Some other considerations should be taken into
account in the fuel amount estimation, such as the expected amount of fuel that has to
evaporate to the gas form during consumption of LH2 to maintain the tank temperature [29].
Ibrahim Seddiek, Mohamed Elgohary, The hydrogen-fuelled internal combustion engine
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Bureau Veritas (BV) Classification Society has developed a comprehensive set of
guidelines for the use of hydrogen fuel onboard commercial ships. The guidelines combine
existing regulations for gas fuelled ships with regulations for terrestrial fuel cell power
systems adapted for the application onboard ships. The guidelines are now being tested on a
number of pilot projects, of which the Hydrogen-Powered Hybrid Electric Harbour Tug is a
good example [34]. Bureau Veritas is looking forward to work together with partners within
the industry to further develop the use of clean technologies in shipping [35-36].
Figure 2 Hydrogen fuel bunkering system
5. Hydrogen-fuelled internal combustion engines
The last decade has produced significant advancements in the development of the
hydrogen-fuelled internal combustion engine. The beginning was the use of hydrogen as fuel
for spark ignition engines. However, some problems were encountered related to the issues
such as pre-ignition, knock, NOx control and loss in power density. Therefore, much effort
has been put forth in the development of advanced hydrogen engines with improved power
densities. The hydrogen fuelled internal combustion engine (H2ICE) technology passed
through several stages as follows [37-38]:
i. Pressure-boosted H2ICE: problems of pre-ignition, knock and NOx control are
heightened during boosted operation because boosting pressure increases charge pressure and
temperature.
ii. Liquid-H2ICE was the second phase of H2ICE development where the primary
benefit is the higher stored-energy density of hydrogen available with liquefaction. Moreover,
the charge-cooling effect of the cold hydrogen provides for several advantages compared to
conventional gaseous port fuel injection. However, practical difficulties of liquid storage
include the energy penalty of liquefaction, evaporation during long-term storage, and the cost
of onboard cryogenic dewars.
iii. Direct-injection hydrogen-fuelled internal combustion engine (DI-H2ICE): the direct
injection H2ICE has long been viewed as one of the most attractive advanced H2ICE options.
Preferential of direct-injection hydrogen is based on: the high volumetric efficiency, and the
The hydrogen-fueled internal combustion Ibrahim Seddiek, Mohamed Elgohary,
engines for marine applications with case study Nader Ammar
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potential to avoid pre-ignition. The challenge with DI-H2ICE operation is that in-cylinder
injection requires hydrogen-air mixing in a very short time.
iv. H2ICE-electric hybrid: A hybrid-electric version of an H2ICE offers the potential for
improved efficiencies and reduced emissions without the need for aftertreatment. In a hybrid
electric system, the ICE operates either in series or parallel with an electric motor.
6. Hydrogen marine power plants
Hydrogen is suggested to be used for the existing diesel engines to minimize the cost
as much as possible. The suggested engine will be operated with hydrogen being directly
injected into the cylinders, as shown in Figure 3. To initiate the combustion process, low
energy sparks will be needed to avoid using amounts of diesel fuel. Fuel pumps and sparks
are to be electronically controlled (camless engines) to ensure the optimum performance at
various operating conditions, as shown in Figure 4.
One of the main problems related to the adoption of hydrogen for internal
combustion engines is the engine knocking that arises due to malfunction of air fuel ratio and
intake temperature.
Figure 3 Schematic engine control systems
Figure 4 Hydrogen fuel system
Ibrahim Seddiek, Mohamed Elgohary, The hydrogen-fuelled internal combustion engine
Nader Ammar for marine applications with a case study
30
Different propulsion arrangements can be used to propel the ship. One of them is to
use the hydrogen internal combustion engine connected to the propeller via gearbox, and
another one is a modern arrangement generating electricity by alternators to drive electric
motors coupled to the propellers. Each arrangement has its advantages and disadvantages
related to the field of usage. Figures 5 and 6 show these arrangements. Smaller hydrogen
engines will be needed as shown in Figure 6 for operation at part load in harbours and for
manoeuvring purposes, and also for use with auxiliary engines (A/E).
Figure 5 Direct coupling propulsion Figure 6 Hydrogen electric propulsion
Generally, waste heat in exhaust gases, which is mainly high temperature, is very
important because it eliminates the need for exhaust gas boiler, steam may be directly used
onboard ship for heating or for any other process requiring high temperature [39].
Another use of hydrogen is for fuel cells. Huge developments have been achieved in
this sector over the past few years. However, in the marine field it has been used only in the
naval vessels market for auxiliary power generation and for quiet operation of submarines.
Concerning the commercial market, the development achieved so far is not enough to
convince ship owners to use this fine technology product. From all types of fuel cells, only
two types are the candidates for the use onboard. The proton exchange membrane fuel cell
(PEMFC) and the molten carbonate fuel cell (MCFC) fuelled by hydrogen rich fuels like
natural gas or alcohols [40].
A number of ship design firms introduced designs for many ship types working with
fuel cells as an auxiliary power source or for propulsion in hybrid modes [41]. In the marine
sector, several research programs focused on the use of liquid hydrogen onboard ships in
combustion engines or fuel cells. Although the use of hydrogen for marine applications
provides a lot of advantages, especially regarding environmental issues, it is still restricted
due to safety and storage problems.
7. Case study
The case study refers to repowering operation for a RO/RO ship, named Taba,
operating in the Mediterranean Sea. The ship [42] is originally fitted with 2 MaK 9M453
engines with 2700 kW brake power each. Two alternatives were under consideration, either
using pre-mixing of hydrogen and air before entering the combustion chamber or direct
injection of hydrogen into the cylinders after compression. The analysis was done for both 2
The hydrogen-fueled internal combustion Ibrahim Seddiek, Mohamed Elgohary,
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and 4 stroke cycles based on the Otto standard cycle. The highest useful compression ratio
(HUCR) for the hydrogen-air mixture is limited to 6 to avoid explosions [43]. The
compression ratio is also limited between 2 and 6; compression ration less than 2 produces a
very high combustion temperature and the values higher than 6 produce unstable combustion.
Figure 7 shows the comparison between diesel and hydrogen fuels and the variation of
combustion temperature at different excess air factor.
Figure 7 Hydrogen and diesel combustion temperature versus excess air factor
There are some points to be clarified concerning the comparison in Figure 7:
i. The efficiency of the hydrogen engine is lower than that of the diesel engine due to
higher cooling water losses in the case of hydrogen. Without all these losses the temperature
of combustion inside the cylinders may reach very high levels that may put the engine in a
critical state. The obtained result is close to the results published in [44] which demonstrated
the ability of achieving efficiency of about 32%.
ii. Due to the higher energy contained in hydrogen, less fuel is used by mass to produce
the same power, but the product of fuel consumption and calorific value in both cases will
yield a lower value in the case of hydrogen and this is due to lower efficiency.
iii. Very low brake mean effective pressure is available in case of hydrogen if compared
with diesel despite the higher turbo charging pressure in the hydrogen engine (in diesel engine
only 3.3 bar turbo charging pressure is used), this is due to the different nature of gaseous fuel
with a very low density.
iv. Due to lower efficiency and lower density of hydrogen fuel, bigger engine
dimensions are needed to produce the same power at the same speed of the diesel engine. It
can be concluded that the hydrogen engine is still in need of a considerable effort in order to
reach the competition phase. However, attempts to use the hydrogen fuelled engine instead of
the diesel fuelled engine must be continued to overcome those obstacles.
Condition (1): Pre-mixing
Temperature = 127OC (at start of compression inside the cylinder) [45]
Pressure = 1 bar (atmospheric),
Compression ratio = 6
Ibrahim Seddiek, Mohamed Elgohary, The hydrogen-fuelled internal combustion engine
Nader Ammar for marine applications with a case study
32
Figure 8 shows that at the excess air factor for the bore of 4-stroke exceeds the bore of
2-stroke engines by percentage of 25%. The 2 stroke cycle gives fewer diameters; however,
this is larger by 6cm than the installed engine bore of 32 cm. Figure 9 explains the relation
between brake specific fuel consumption at different excess air factor.
Figure 8 Cylinder bore as calculated for condition (1)
Figure 9 Thermal efficiency and fuel consumption for condition (1)
Condition (2): Direct injection
Temperature = 127OC
Pressure can be varied since no restriction on compression ratio. Figures 10 and 11
illustrate the variation of engine bore at different compression ratio for different pressures for
the 4-stroke and 2-stroke engine respectively.
The hydrogen-fueled internal combustion Ibrahim Seddiek, Mohamed Elgohary,
engines for marine applications with case study Nader Ammar
33
Figure 10 Bore diameter for Condition 2 (4 strokes)
Figure 11 Bore diameter for condition 2 (2 strokes)
The required diameter can be achieved with a reasonable supercharging pressure. Thus,
direct injection with 2-stroke cycle is the best choice for the engine design. From Figure 12 is
evident that for obtaining the required diameter, a pressure ratio of 9 with supercharging
pressure of 3.7 bar is adopted.
Figure 12 Thermal efficiency and fuel consumption for direct injection condition
Ibrahim Seddiek, Mohamed Elgohary, The hydrogen-fuelled internal combustion engine
Nader Ammar for marine applications with a case study
34
The comparison between the engine characteristics of the hydrogen engine and the
ship’s original engine (M32C Diesel Engine) can be summarized as shown in Table 1.
Table 1 Comparison between engine characteristics of hydrogen engine and M32C
diesel engine
Hydrogen
M32C
Engine speed (r.p.m)
775
600
Pressure ratio
9
12.8
Heating value of fuel (MJ/kg)
130
42.7
Bore (cm)
32
32
Stroke (cm)
42
42
Engine power (kW)
2700
2700
Thermal efficiency (%)
29.57
47
Specific fuel consumption (g/kW.hr)
93.46
178.98
No. of cylinders
6
6
Mean effective pressure (bar)
10.02
25.9
Compression pressure (bar)
75.57
84
Combustion pressure (bar)
132.4
124
The outcome of the preliminary design calculations reveals that the bore of the engine
piston will be the same for the two engines, but the thermal efficiency of the hydrogen fuel
cycle shows a decline compared to that of the original diesel fuel cycle. On the other hand, the
specific fuel consumption is reduced to 93.46 g/kW.hr in case of hydrogen fuel.
The engine flow rates can be summarized as:
Fuel : 93.46 g/kW.hr (252 kg/hr)
Cooling water : 67.83 kg/kW.hr (183007 kg/hr)
Air : 13 kg/kW.hr (35087 kg/hr)
Exhaust : 13.1 kg/kW.hr (35339 kg/hr)
Regarding the fuel storage tanks onboard the ship; the volume of the ship fuel tanks
(DMA and DMB) is 706.8 m3. When these tanks are used for LH2, only 90% of this volume
can be filled due to insulations. Thus, volume will be 636.1 m3. The volume of LH2 required
for 8 days voyage (2~3 stops in ports) is 1492 m3. This means that the present volume, for
complete hydrogen power plant, i.e. both the main engines and the generators run on
hydrogen, will be sufficient only for a voyage of 3.4 days. Consequently, the extra volume of
about 950 m3 will be needed. This volume can be deducted from the twine deck area as shown
in Figure 13. As can be seen, two times larger tank space in the ship under consideration is
needed to accommodate the hydrogen fuel for only 8 days rather than 20 days as the ship
originally travels.
This problem will occur only in cases when considering the conversion of existing
ships to run on hydrogen, but new designs should include their own hydrogen tank spaces.
Another solution may be available if new storage techniques are invented to overcome this
problem. New techniques are required to provide fuel storage with appropriate energy density.
The hydrogen-fueled internal combustion Ibrahim Seddiek, Mohamed Elgohary,
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Figure 13 Modified hydrogen fuel tanks
8. Conclusion
Several issues must be taken into consideration when trying to adopt a new type of
fuel like hydrogen, especially for marine applications where strict rules and regulations
control the design and manufacture of waterborne vehicles. Safety and storage problems are
the main issues arising when talking about the use of hydrogen as fuel. Combustion of
hydrogen inside internal combustion engines has been, and still is, the subject of numerous
research programmes in many countries. Like in the case of natural gas, one of the main
problems associated with the application of hydrogen in internal combustion engines is engine
knocking; air fuel ratio and intake temperature were found to be the main causes for this
problem and their optimization is a must in order to have a knock free engine.
The present paper discussed the different stages of hydrogen gas cycle beginning
with the production process, from clean energy, until using it as fuel for internal combustion
engines onboard a RO/RO ships, named Taba, operating in the Mediterranean Sea. Compared
to the diesel engine, the hydrogen engine was found to be lower in thermal efficiency, mean
effective pressure and fuel consumption, while the both engines seemed to have the same
value of compression and combustion pressure. In addition, some adjustments are needed
regarding the engine’s dimensions, valves timing and fuel system.
However, regarding the ship’s operation, some problems need to be solved. First of
all, it is necessary to make some modifications for the use of hydrogen onboard ships, like for
instance, the fuel storage capacity, as the fuel tanks of the ship under research are not capable
to accommodate the hydrogen needed. The study has shown the need to increase the volume
of bunkering tanks from 706.8 m3 (heavy and diesel fuel) to 1492 m3 (hydrogen fuel) so that
the vessel can provide the necessary space for the hydrogen storage. The design results may
seem strange to the professional reader and yield to the heavy, big and expensive engine, but
it must not be forgotten that this is a first step. Other refinement procedures will follow and
also prototype experiments have to be made to assess how far the calculations are from the
real world and after that a fine tuning processes will follow. This procedure can also be
applied to different types of power plants.
Ibrahim Seddiek, Mohamed Elgohary, The hydrogen-fuelled internal combustion engine
Nader Ammar for marine applications with a case study
36
Acknowledgment
This work was funded by the Deanship of Scientific Research (DSR), King Abdulaziz
University, Jeddah, under grant no. (980-580-D1435). The authors gratefully acknowledge the
DSR for their technical and financial support.
Nomenclature
A/E
Auxiliary engines
HUCR
Higher Useful Compression
Ratio
B.V
Bureau VERITAS
IMO
International Maritime
Organization
BTE
Brake Thermal Efficiency
LH2
Liquefied hydrogen
CO
Carbon Monoxide
MARPOL
Marine Pollution
EES
Engineering Equation Solver
NOx
Nitrogen-Oxides
GH2
Gas Hydrogen
P.M
Particulates Mater
HC
Hydrocarbons
SOx
Sulfur- Oxides
HICE
Hydrogen Internal
Combustion Engines
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Submitted: 19.10.2014.
Accepted: 11.02.2015.
Ibrahim S. Seddiek, isibrahim@kai.edu.sa
1-Department of Marine Engineering, Faculty of Maritime Studies, King
Abdulaziz University, Jeddah, Saudi Arabia.
2- Department of Marine Engineering Technology, Arab Academy for Science,
Technology & Maritime Transport, Alexandria, Egypt.
Mohamed M. Elgohary
Department of Marine Engineering, Faculty of Maritime Studies, King Abdulaziz
University, Jeddah, Saudi Arabia.
Nader R. Ammar
Department of Naval Architecture and Marine Engineering, Faculty of
Engineering, Alexandria University, Alexandria, Egypt.
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... Particularly, NO x and SO x are considered especially damaging [1][2][3][4]. In the marine field, even stricter limitations imposed by the IMO (International Maritime Organization) and other organizations regulate emissions from ships [5][6][7][8]. Regarding SO x , the maximum content in the fuels is limited for ships that do not have any post-treatment device. Regarding NO x , IMO establishes even stricter maximum emissions depending on the engine and region. ...
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