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Reducing the ship rolling motion is an important subject of the ship motion control. In addition, the fin stabilizer is one of the most effective ship stabilizers, which plays an important role in decreasing fuel consumption, improving the ship seaworthiness, giving a longer life for the ship, ensuring the equipment on the ship-working better and making the ship members feel comfortable, advance battle effectiveness of the naval ships. In our research, we concentrate on a hydrofoil fin stabilizers, which are used in both sides of ships. Our aim is to profile the optimum design of foils to enhance the effectiveness of ship stabilizers by more investigation in different experimental models& comparing them. Finally, we have reached the best form and the best dimensions of hydrofoil fin stabilizers used in the experiment, which is NACA-04, which is better than the other foils. [ABSTRACT FROM AUTHOR]

In this study authors observe that looking the overpopulation in Egypt, significant concerns should be considered in order to respond to energy demand of its expanding population and its agricultural sector and the Nile River may not be able to keep up with the demand at this time due to changes in the monsoon pattern and a loss in storage capacity. So Egypt needs to increase its energy using clean, sustainable and renewable resources of such as solar, wind, geothermal resources side by side with the usage of the oil and natural gas resources on which it mainly depends and also develop low-carbon society. Authors try to solve the problem of the inconsistent power generation using renewable energy through introducing hybrid system between solar chimney and geothermal, this system will overcome the drawback of solo solar chimney system of being unproductive at night as well as the low potential energy extracted from geothermal and will give us energy all day and night. And in addition to this authors use abandoned oil and gas wells to reduce the initial cost for drilling new one. From this hybrid system we can get energy to generate electricity and we can also use it to get fresh water from operating a desalination unit. A numerical simulation for a 2D axisymmetric model of solar chimney and the associated heat exchange with the ground took place. The work presented in this paper simulates the velocity and temperature inside the solar chimney as the ambient temperature of air outside is 293.15 K and the power output of the proposed system will be about 106.38 KW. The turbulence model used is standard k-ε model and boussinesq model is adopted. [ABSTRACT FROM AUTHOR]

The number of ships is increasing day by day which require more fuel and produce more emissions. In addition, petroleum resources are limited in nature and emission standards are being tightened day by day. The IMO has set the target to reduce ships' CO2 emissions by at least 40% by 2030 compared to the levels produced in 2008. In order to minimize greenhouse gas emissions from ships, EEXI and CII, a series of changes to current laws, have been accepted by IMO. The classification organization has consequently set out to establish emission caps, use EEXI calculation criteria, and mandate that ships implement the essential requirements to comply. Those scenarios are motivating the researcher to find a non-petroleum clean energy source, in order to achieve the aforementioned goal, gaseous fuel replenishment is beneficial. In this study, methane gas supplementation has been done to diesel engine. The investigation was carried out to analyze the performance and emission of diesel engine using 0–75% substitution of diesel indicated power by methane energy in dual fuel mode at varying load (25%, 50%, 75%, and 100%). The results demonstrate that methane energy sharing (MES) lowers brake thermal efficiency (BTE) while unaccounted heat loss increases. For the purpose of determining the non-thermal impact of CH4 on HOx emissions, a comparison of NO and NO2 emissions has been given below. Combined reduction in nitrogen oxide and soot emission makes the outcomes of this study more suitable to implement for achieving the strict emission norms. Therefore, CH4 augmentation is advantageous in mid- and high-load circumstances with reduced emissions and energy consumption. [ABSTRACT FROM AUTHOR]

A preliminary design for a Hybrid Renewable Energy Source (HRES) system to satisfy electrical load demand of a proposed Reverse Osmosis (RO) seawater desalination plant in Abuqir, Alexandria, Egypt. The design uses HOMER PRO™ software, which analyzes user-provided data to optimize and simulate the system. Fresh water consumption data was obtained and processed to match Abuqir' s demand. The proposed HRES-RO plant will use solar and wind energies equally. The results shown that the design is initially feasible with a projected COE OF $0.158/kWh. [ABSTRACT FROM AUTHOR]

The present study aims to address two pressing issues, namely the evaporation of water in Lake Nasser and the adverse impact of elevated temperatures on the efficiency of photovoltaic solar systems. To resolve these problems, the installation of floating solar panels on a portion of Lake Nasser is proposed as a feasible solution. A mathematical model has been established to simulate this scenario and calculate the extent to which evaporation is reduced and the performance improvement of the solar panels owing to the cooling effect of water. The unit structure of a floating solar station has been adopted as a representation of the floating solar panels installed on Lake Nasser. This model provides valuable insights into the potential benefits of this innovative approach to harnessing renewable energy. [ABSTRACT FROM AUTHOR]

Autonomous Underwater Vehicles (AUVs) are devices used for underwater inspection in many fields. The need for a more persistent human presence on sea is driving the development of increasingly more efficient AUVs. Using batteries which is costly to charge, can lead to a limited operation time according to AUVs batteries capacity which means low endurance with the risk of losing the AUV due to batteries failure. Ocean thermal energy (OTE) is a type of renewable energy used to run AUVs which can be harvested from the temperature variation between the surface and bottom of the ocean through the utilization of phase change material (PCM). This study investigates the selection of appropriate PCM regarding melting and freezing temperature through model of thermal engine by experimental method. The thermal engine with a double-tube structure was developed and isostatic pressing technology was applied to improve the performance for buoyancy driven, referencing powder pressing theory. Furthermore, the material selection and dimension determination were discussed for a faster heat transfer design by thermal resistance analysis. The results showing that Hexadecane is selected as the thermal material with high thermal conductivity and volumetric change rate. [ABSTRACT FROM AUTHOR]

The Overtopping Breakwater for Energy Conversion (OBREC) is a typology of overtopping wave energy converter integrated into a traditional rubble mound breakwater. The OBREC has the same functions as the traditional structures with the added value of energy production. This paper aims to compare between different designs of OBREC and choose the optimum to be applied on an Armored rubble mound breakwater located in San Stefano Alexandria. By applying mathematical model, results show that the yearly power production after applying OBREC is 49 MWh generated from mean wave power at that area is about 196 MWh/year, and with OBREC mean efficiency about 20 %. [ABSTRACT FROM AUTHOR]

Hospitals can be classified as one of the main consumers of electrical energy in building sectors due to their challenging environmental as they operate 24 hours a day, seven days a week in a life-or-death situation, with massive and vital equipment that consumes enormous amounts of electricity. It is imperative that hospitals invest in energy efficient solutions to reduce energy bills, reduce carbon footprint and promote renewable energy resources. The purpose of this study is to model a clinic (small hospital) geometrical and thermal property in Design Builder software, generate a site- specific weather file based on records measured near the site, evaluate internal load schedules based on a detailed survey and collect monthly records for heating, lighting, and cooling loads. All data used in modelling were collected from a clinic in the Arab Academy for Science and Maritime. After the data were modelled, the results were compared with the monthly energy bills of the clinic (obtained from the facility department) for the past year to validate the power consumption within the healthcare building. Then, numerical simulations were performed to cover the electrical consumption. This was done on 3 scenarios, each using a different renewable energy strategy and utilising the roof area. The first scenario was using 151 PY modules, which produced 66,840 KWh. The second scenario was using 25 wind turbines which produced 67,123.98 KWh. And finally, the third scenario was a hybrid of 90 PY modules and 14 small turbines which produced 68,765.24 KWh. [ABSTRACT FROM AUTHOR]

Facility layout optimization is to set best physical configuration of the site facility to perform high production capacity and improve the performance of the organization. Marin fabrication yard is one of factory consists of several fabrication activities using a large area. Construction activities varied to produce different types of marine units and offshore platforms like decks, jackets, subsea guides, piles, deepwater oil and gas structures, and ships. This hug structure needs a suitable site area with a good arrangement of a fabrication facility to achieve best and fast production flow. The objective of this study is to optimize the yard facility layout for building and fabrication of marine and offshore units using Computerized Relative Allocation of Facilities Technique algorism. In this paper facility layout problem (FLP) for the marine fabrication yard (Alexandria yard) was verified as study work case. Computerized Relative Allocation of Facilities Technique algorism (CRAFT) used to improve the already existing marine yard layout. Also, Sample data project was collected to determine the amount of fabricated material as real data input for required calculations. Alternatives layout produced by CRAFT algorithm and compared with existing marine yard layout (Alexandria yard) to defined best layout design, the comparison found that the computerized layout design provided by CRAFT algorithms provides better layout design results and improves the initial material transportation from 187608.64 Birr to 76163 Birr By applying different types of iteration like switch, relocating and resizing the department. [ABSTRACT FROM AUTHOR]

Egyptian riverine networks are distributed from Upper Egypt to the Mediterranean Sea, Northern. Hydrokinetic energy uses the flowing water of the riverine systems such as rivers, canals, streams, dykes, and channels. According to the rural areas of Egypt where low flowing water velocity with ultra-low head of water exists at different regions, the gravitational water vortex turbine is one of the best options. In this study, artificially induced gravitational water vortex in the basin is investigated to extracts energy. Numerical model has simulated the gravitational water vortex turbine, after a sufficient sensitivity analysis with 6% error deviation. Several simulations have conducted and evaluated the required parameters and values. The results showed that the V-shaped basing and its inlet notch are directing the flowing current toward the basin circumference to its outlet hole, while increasing the current velocity that generates swirl. The maximum power coefficient of the runner is 0.34 achieved by 75 RPM and current velocity 1.6 m/s. Also, the lowest value is 0.12 occurred by 95 RPM and current of 3.1 m/s. Meanwhile, the highest thrust coefficient is 0.90 by current velocity of 3.1 m/s and 35 RPM, the lowest thrust coefficient is 0.24 by 1.6 m/s and 95 RPM. [ABSTRACT FROM AUTHOR]

Short-Term significant wave height (SWH) forecasting is essential for many wave energy-related tasks. SWH forecasting techniques may be clustered into three categories: namely, classical, statistical, and data-driven techniques. Data-driven techniques offer less computational burden than classical numerical forecasting methods and improved forecasting capabilities than statistical methods. However, deep learning techniques - even though offering state-of-the-art accuracy in forecasting - long training time and un-interpretability prevent its mainstream adoption. These issues can be mitigated by proper data preparation. this paper proposes a fast and efficient technique that offers excellent forecasting accuracy and fast training time. A combination of Ensemble-Empirical-Mode-Decomposition and Linear Regression (EEMD-LR) is used to forecast the 1 Hr. SWH, with input features' lag chosen using Bayesian optimization. Several National Buoy Database Center (NDBC) buoys were used to validate the model. The proposed technique outperformed many published techniques, achieving an average improvement of 3.5% and 50.9% in coefficient of determination and mean absolute error metrics, respectively eight state-of-the-art deep learning techniques. Additionally, it offered a short training time with fewer data required for training. [ABSTRACT FROM AUTHOR]

The concept of converting ocean thermal energy has been around for a long time. The viability of OTEC power plants as prospective sources of renewable energy has been examined. However, because the temperature difference between the surface and the deep sea is modest, the OTEC system has low efficiency and high investment costs, and it has a long pipe line and high pumping costs for using cold deep water. The OTEC depend on the temperature difference between the surface and the deep waters. Therefore, we suggest using PCM to store heat during the day and operate the system for more working hours. As a result, the OTEC system is used in conjunction with a solar system and PCM in this research. The aim of this paper is to reach an optimum design and optimum layout for experimental model to raise and improve the efficiency of the OTEC by using Mathematical model. It is expected to increase the number of operating hours of the system by greater percentage after using the phase change material in the tank of the ideal size and with a specified amount of phase change materials. And based on the increase in the number of operating hours at night when the temperature difference decreases, the efficiency of the overall system will increase. [ABSTRACT FROM AUTHOR]

Failures of marine risers during hydrocarbon extraction can result in catastrophic offshore oil and gas mishaps, resulting in loss of life and environmental harm. So, marine risers' failure due to vortex-induced vibrations (VIV) because of high currents has been studied to acquire insight into their prevention. Vortices that are created in the viscous boundary layer tend to detach at the downstream end of the cylinder. A fairing is a body with a hydrofoil shape attached to the marine risers to reduce VIV. The effect of VIV on a marine riser in high currents is investigated using a numerical simulation. The research aims to enhance the ability of a typical water-drop fairing to suppress VIV. The study will be performed using Computational Fluid Dynamics (CFD) (Ansys Fluids). A vertical hole is applied to a water-drop fairing that has a top shape angle of 80° to improve the suppression of the VIV. The root mean square of the lift coefficient (ClRMS) is used to compare the behavior of the fairing in the VIV. The position of the vertical hole that gets the lower value of RMS Cl is chosen to be the optimum place for the vertical hole. The CFD model has been validated with experimental data and proven acceptable. The results of the current study conclude that the optimum position of the vertical hole is 0.13D from the tail of the faring. [ABSTRACT FROM AUTHOR]

Wave energy has great potential to solve the unrelenting energy deficiency in Egypt. It has zero emissions and is therefore environmentally friendly energy. It can be used at any time as it is a renewable energy. In this work, the relationship between well turbines and wave energy is studied as a suitable option for the coast of Egypt. However, Egypt has extensive coastlines on the Mediterranean and the Red Sea. Both experimental and mathematical analyses have been studied. In the experimental setup, a comparison between different types of airfoil in bidirectional flow is arranged. The setup consists of a reciprocating piston that compressed the air in the laboratory instead of wave motion. In the mathematical model, the starting and running characteristics of wells turbine are studied, by changing the starting rotation speed, starting Load on the system and changing mean rotor radius of the rotor. NACA00l2 turbine profile is proven to give the highest rotational speed with 78.53 mis better than NACA00l5 by 7%. [ABSTRACT FROM AUTHOR]

The move towards serious adoption of solar energy is now beginning to take shape. The use of solar energy is now being seen as part of the energy mix for the marine sector in the Nile river and solar power will most likely play an important role in helping to reduce fuel consumption and emissions from marine units, especially as further solar energy- related technologies are developed. In fact, the sea freight shipping industry has begun to practically look at ways to reduce fuel consumption and operate in a more environmentally friendly way. This paper reports on a project which is concerned with the utilization of solar power to run cruise ships (floating hotel) in the Nile river. The main concern is the performance of PV modules in the Aswan/ Luxor area where the ambient temperature is elevated most of the year which reduces solar panel efficiency, and consequently, the rewarding returns on the investment and shortening the payback periods. In this paper, this concern is addressed and a new methodology to cooldown the PV modules and maintain the PV power output figures within an acceptable margin is presented. The proposed system is a mix of forced air draft and water injection at the backside of the P V module, in addition, a film of absorbent foam sheet is fitted to maintain the contact of water injected with the back sheet of the PV module and secure the continuous cooling of water injected with the forced air draft. A special experimental setup is designed, fabricated and arranged to carry on two different cooling techniques to cool down the solar panels one with airflow alone and the second with airflow and water injection at the backside of the panel. The proposed technology has resulted in a considerable decrease in PV module temperature and a 3O % increase in power output. [ABSTRACT FROM AUTHOR]

The results of an analysis to minimize the energy usage of the Middle East Oil Tankage & Pipelines Company (MIDTAP) marine port in Alexandria, Egypt are presented in this paper. The project takes a comprehensive approach to data collection from the MIDTAP marine port's maintenance department, an energy analysis, and the development of a building simulation model. Many energy-saving measures have been found during the energy audit, including replacing existing florescent lights with LED lamps and a lighting control system, as well as reflecting solar radiation with window film. The building energy model was created with DesignBuilder and then calibrated based on the field observations and measurements. Several energy management options were assessed using the calibrated model, based on a calculation of simulation and real electricity usage in KWh for the year 2020. According to the findings, energy demand can be cut by up to 61.7 percent. [ABSTRACT FROM AUTHOR]

As part of an effort to investigate the feasibility of transitioning marine ports away from reliance on national grid electricity and toward green power-based ports, hydrogen could be used to supplement diesel fuel in an internal combustion engine, the aim of this paper is to developing a mathematical model for the optimum performance of HHO gas generator according to ICE specification and clarifying the effect of cell design parameter change on gas production rate. The gas production rate can control by the current apply to the generator and the ideal gas production rate is 0.25 Liters/minute per 1L of engine size. [ABSTRACT FROM AUTHOR]