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The study aims to improve the thermal resistance of concrete by using natural fibre. In general, in Gulf countries, the solar heat is too high during the summer season, causing indoor heat in buildings. To combat this, air conditioners are used frequently, which is harmful to the environment and human health. Although there are many materials available to prevent heat at present, this study looked at how to effectively reduce heat indoors by using natural materials. This date palm fibre is a natural material that is widely available in the Gulf region, and it can be used to protect people from solar heat. The primary goal of the research is to determine the mechanical properties and thermal conductivity of concrete with various percentage of date palm fibre. The study discovered that when 0.2% date palm fibre is added to the concrete dosage, to have high thermal resistance and it was proved by the experimental study. Date palm fibre is added in concrete at 0% to 3% with a interval of 0.2%. (DPFRC) Date palm fibre reinforced concrete has excellent thermal resistance and compressive strength from test results. It will boost green energy technology in construction industry. [ABSTRACT FROM AUTHOR]

The requirement for energy is increasing on a large scale in the industrial and domestic sectors due to the rapid industrial growth and human living standards. International organisations are creating strict laws and guidelines at the same time to limit the usage of traditional fossil fuel-based electricity generating. Additionally, fast-developing countries like Oman are putting numerous plans to integrate renewable energy in the residential and industrial sectors as part of their commitment to lessen the potential for global warming. The government is taking proactive steps to use solar-based systems in household applications because Oman has a strong potential for using solar power and has a high demand for electricity from the residential sector. Since Oman has a promising potential to use solar power and a large demand for power from the residential sector, many steps are being taken to use solar-based systems in domestic applications. Presently, the hot water needs of domestic as well as many industrial consumers are met by grid electricity. The solar PV technology is a desirable alternative for using renewable energy. However, installing a solar thermal energy conversion system is a potential way to use solar power for producing hot water because solar thermal collectors have a greater conversion efficiency (55–75%) than PV collectors (10–20%). Thermal energy storage systems are also essential for the efficient use of solar thermal energy. Phase change material (PCM)-based thermal storage, one of the more modern technologies, has been recognised as a dependable solution in earlier investigations. However, for this strategy to be successfully applied in a particular location, it is necessary to analyse the quantity and quality of solar energy available. In this study, the technical feasibility of using PCM thermal storage to supply 200 litres of hot water per day to a residential building is examined. The size and specification of the thermal collector have been selected based on the simulation studies. For this purpose, the system advisor model (SAM) of the National Renewable Energy Lab (NREL), USA, and the weather data of Shinas, Oman, from the NASA database were used. To store 6 MJ of heat collected per day from two solar thermal collectors, 50 kg of paraffin wax having a melting point of 60oC was used. An experimental setup has been fabricated as per the optimum design parameters identified from the simulation studies in SAM, and tests have been conducted to find out the performance of the system. According to the findings, the system could save 1168 kWh of AC electricity annually. [ABSTRACT FROM AUTHOR]

The date palm tree is a very important crop that is grown on a large scale in Gulf countries like Saudi Arabia and the Sultanate of Oman. Date palm stems and leaves come in large quantities as agricultural residues. The stem and leaves of date palm trees, which are common in the Al-Batinah region, might be easily and cheaply used to extract large amounts of fibre. Moreover, they have durability, as well as various strand textures. Using natural fibres made from renewable resources benefits the environment in terms of waste material use and eco-friendly disposability. Due to their availability, widespread use, renewable nature, cost-effectiveness, and eco-friendliness, natural fibre composites have become the focus of research and development. Use of composite materials has grown more common in vehicle, aircraft, marine, and civil structures due to their balanced mechanical qualities. By fortifying the fibres into polymers, properties including compression, impact strength, hardness, and flexural strength of the composites must be ensured. To create fibre/epoxy composites with improved qualities, date palm fibres are more reliable. However, the strength and properties of the fibres may not be the same for the trees grown in different regions. Therefore, in this work, the strength of the composite produced from DPFs of local varieties is tested for the above-specified mechanical properties. The major objective is to find the possibility of using waste date palm tree fibres (DPF) to get a good natural polymer composite which and can be used for different applications. A suitable epoxy has been used as the binder, and the absorbent nature of DPF is controlled by using sodium hydroxide. After treatment, it enhanced the properties of composites. The maximum impact strength and flexural strength of the composite were observed at 21.42 kN/m and 260.41 MN. which proves the reliability of the local DPF for many high-tech applications. [ABSTRACT FROM AUTHOR]

The entire modern world is dependent on energy. Providing cooling with renewable energy sources, such as solar energy, is one of the primary answers to the energy and environmental issues. Phase change materials (PCMs) play a significant role in the utilisation of solar energy in cooling applications. Recent study on solar energy using PCMs for low and medium temperature cooling applications indicates that PCMs are widely employed in solar thermal cooling, transport refrigeration, and commercial food outlets. Since low-temperature PCMs can maintain the temperature of small-scale refrigerators for an extended time, it can be used to maintain the space temperature of the appliance without the use of an electrical energy storage during the night. The primary factors in adapting a conventional system to work with solar energy with PCM are performance parameters such as pull-down time and on-off cycle of the compressor. In this paper, therefore, the experimental findings for the pull-down time and on-off cycle time of a 210-liter solar refrigerator with and without a PCM are provided. The experimental data revealed that the compressor's pull-down time and off-time were raised by 78% and 6.1 times, respectively. In addition to enhancing performance and facilitating temperature maintenance within the refrigerated space, the per-day energy consumption was reduced from 14.4 to 18.5% as compared to the system without PCM. It was confirmed that the use of PCM in refrigeration systems can play an essential role in enhancing their overall performance. Furthermore, this study could serve as a key link between the PCM and all currently available small-scale solar-powered household cooling appliances. [ABSTRACT FROM AUTHOR]

As part of Oman's vision 2040, electricity from renewable energy should replace 30% of the country's total power by 2030. Furthermore, the power for electric vehicles is expected from renewable power. Recently the Oman Authority for Electricity Regulation (AER) revised the tariff system and due to this generating of energy from solar energy is becoming popular. To implement the PV technology, many challenges including cost of electricity, technological growth and policy must be addressed. Grid Connected PV (GCPV) system may be one of the options to overcome the above issues. It could decrease peak load demands, besides contributing to eco-friendly power generation. This paper investigates the techno-economic and environmental aspects on implementing PV power for electrification of Suhar City which is situated in the northern part of Oman. Photovoltaic (PV) systems can be installed utilizing the available rooftop spaces in the premises and the empty land around the buildings. A 1400W PV system available in Sohar University (SU) was used to collect the required data. The system was simulated in HOMER Pro, and the major parameters needed for the proposed study were analysed. The results showed that the investment in PV system, in Sohar city can be promising. The system showed the yield factor as 1923.6 kW h/kWp/year. Moreover, the proposed system had a capacity factor of 21.7%. The cost of energy and payback period were 0.146 USD/kWh (0.056 OMR/kW h) and 4 years respectively. However, many other factors due to economic challenges, Government policies and social acceptance must be resolved to establish a viable market for PV technology in Oman. [ABSTRACT FROM AUTHOR]

A spatial mechanism commonly employed for the control of angular motion of a body is called Gyroscope. The resistance to change in the direction of rotational axis is called the gyroscopic effect. The torque or turning moment, that opposes any change of the inclination of the axis of rotation of a gyroscope, is called gyroscopic couple. Or in other words, whenever the axis of a rotating body is caused to change direction, a couple is required, called as gyroscopic couple. The reaction to this couple is experienced in aircraft, marine and car engines when changing direction and is also employed in navigating systems. In the present study, a motorized gyroscope apparatus is used to evaluate the active and reactive gyroscopic couple. The apparatus is made up of a brass gyroscope flywheel mounted in a cradle which allows the flywheel to pivot in the x, y and z directions. When the gyroscopic couple is equal to the couple applied by the counterbalance weight; the arm of the gyroscope will run in a horizontally. When the arm of the gyroscope is horizontal, the speed of precession and the spin speed have to be recorded. Knowing the mass properties of the flywheel in addition to these speeds, the gyroscopic couple can be estimated experimentally. From the mass of counterbalance weight and the radius of rotation, the theoretical couple that can be produced by the apparatus can be evaluated. Reasonably good agreement was observed between test and theoretical results. [ABSTRACT FROM AUTHOR]

Sultanate of Oman, a country of subtropical dry climate and extreme temperature variations is keen in to escalating the percentage of green electricity component in power systems and reduce the global warming potential of its energy sector. Literature shows that more than 40 % of the total electricity demand is from residential customers and out of this, 70 % is owing to space-cooling loads. Average annual solar irradiance in major part of the country is 5.8 kWh/m2/day which attracts Photo Voltaic (PV) technology for power generation. Since the electricity tariff has been changed recently, replacing the grid electricity with the Solar PV power could be an attractive option. Therefore, the feasibility of using PV power for a 3.5 kW domestic cooling system was modelled in RETScreen software, and the major parameters related to feasibility were calculated. A 3 kW PV array with 300 W modules was uses as the power plant. Capacity factor in the region was taken as 20%. Total annual electricity exported to the air conditioning system was calculated as 5431 kWh. Annual income which can be generated from the PV electricity while exporting to the grid was 679 $. When the Natural gas based combined cycle power plant is replaced with PV, the emission of Green House Gases (GHG) will be controlled and it accounts to 3 tons of CO2 (tCO2). Financial analysis of the project showed that the simple payback period could be 11.7 years with a negative Net Present value (NPV) of 785 $ without any subsidy for the investor and without considering any GHG reduction income. RETScreen financial feasibility analysis showed that the project could be feasible if the authorities give a subsidy for the investors, atleast 20 % in the initial investment and adopt GHG reduction rate of 20 $/tCO2. Simple payback period became 8 years with a positive NPV of 1615$. The analysis revealed that project could be attractive and feasible with the subsidies and policy making for the GHG credit rates along with the expected project life of 25 years. [ABSTRACT FROM AUTHOR]

The application of compound pendulum theory is useful to the determination of the mass distributions of sailing boats, astronauts, farm tractors and so on. If an object is irregular in shape and if the mass distribution is not uniform then the determination of mass properties are difficult by analytical formulae or closed form solutions. Therefore, experimental procedures are optimal rather than the analytical model. This study deals with the fabrication of compound pendulum, experimentation to determine the radius of gyration, mass moment of inertia and acceleration due to gravity at Ibri. [ABSTRACT FROM AUTHOR]

Vibration is the periodic motion due to elastic property of body. Anything has mass and elasticity can vibrate but a rigid body cannot vibrate. Oscillation is also periodic motion as restoring force is due to weight of the body. Even rigid body can oscillate. A wide range of applications found in IC engines, Jet engines, Electro-mechanical drives, reciprocating compressors, etc. Excessive vibration causes sudden structural failure which leads to catastrophe or major accidents. Hence, it is necessary to evaluate natural frequency of vibration to avoid failure of the system due to resonance. The present study aims to determine the natural frequency of torsional oscillation experimentally in un-damped and damped condition. The materials used in the present study are Steel and Brass. For each of the material, the time required for 20 oscillations were noted with and without damper. The steel found better torsional characteristics than brass in un-damped condition as steel has better elastic properties. The effect of mass moment of inertia, length and diameter of the rod on torsional oscillations were studied. Moreover, the damping characteristics of oil was studied and found that higher the damping factor if the amplitude reduction factor is high. [ABSTRACT FROM AUTHOR]

Pressure vessels are employed as storage tanks because they can store fluids at pressures that are significantly higher or lower than the surrounding ambient condition. Pressure vessels can be of any shape, however spherical and cylindrical shapes are usually employed for domestic to space applications. A common design in cylindrical pressure vessel is a cylinder with end caps frequently of hemispherical in shape. Damaged pressure vessels may fail, rupture, or at the very least leak. Poisonings, fires and explosion dangers are among the possible health and safety risks posed by leaking storage containers. Burst failures, which can be significantly more disastrous, can seriously harm both people and property. As a result, it is crucial for figuring out their operational difficulties. Thin cylindrical type 1 pressure vessel for hydrogen storage is considered in the present study. The stresses induced in thin cylinders due to internal pressure are circumferential (also known as hoop stress) and longitudinal stresses. Since, the magnitude of hoop stress is twice the value of longitudinal stress, the pressure vessel has to be designed for hoop stress. A numerical and /or mathematical model is required to analyse the pressure vessels, as experimental evaluation of induced stresses is an expensive procedure. Since Finite Element Analysis (FEA) is the most accepted numerical tool to design pressure vessels, the ANSYS R15 software has been used to evaluate the longitudinal and circumferential stresses and found good in agreement with analytical results. [ABSTRACT FROM AUTHOR]