Engineering Commons^™

Effect Of A Geothermal Heat Pump System On Cooling Residential Buildings In A Hot, Dry Climate, Rania Rushdy Moussa, Ayman H. Mahmoud

Architectural Engineering

ABSTRACT In the last century, electricity demand has doubled due to urban expansion, which has contributed to the formation of more urban heat islands (UHI) and the appearance of environmental hazards such as the global climate change phenomenon. Since residential buildings are considered the main electricity consumer sector in Egypt, they consume up to 42% of total energy consumption, which contributes to increasing temperatures and constitutes UHI in cities. In this context, the research aims to examine the effectiveness of using the closed vertical loop geothermal system (GSHPCV) for cooling residential buildings in a hot, dry climate, such as Cairo, …

The Performance Response Of A Heat Pipe Evacuated Tube Solar Collector Using Mgo/Mwcnt Hybrid Nanofluid As A Working Fluid, Ahmed A. Abdel-Rehim, Shady Henein

Mechanical Engineering

Utilizing a hybrid nanofluid is a promising solution for enhancing the thermal performance of the solar collector in a sustainable manner. In the present work, the effect of using magnesium oxide/multi-walled carbon nanotubes (MgO/MWCNT) hybrid nanofluid on the thermal performance of the evacuated tube solar collector is experimentally investigated. Four different weight ratios of (80:20), (70:30), (60:40), and (50:50) are used for a hybrid of MgO with MWCNTs in a water base, respectively. The experiments are performed at a 0.02% particle concentration and at various volume flow rates ranging from 1 to 3 L/min. The results show an enhancement in …

Responses Of An Axially Rotated Tube Versus Twisted Tube Design As Two Solutions To Enhance The Thermal Performance Under A Non-Uniform Heat Flux Condition: A Numerical Study, Andrew S. Tanious, Ahmed A. Abdel-Rehim, Ahmed A. Attia

Mechanical Engineering

Enhancement of heat transfer in tubes exposed to non-uniform heat flux applications is a key factor in increasing such applications' efficiency.

In the present study, heat transfer in an axially rotating pipe with concentrated heat flux at the lower section of the pipe is numerically investigated and compared to the twisting technique in such applications. The effects of pipe’s length (1, 2, and 3 m) and rotation rate (N = 0–10.5), which is the ratio between the rotational and axial Reynold’s numbers, are studied numerically using ANSYS Fluent while the effect of the twist ratio (S = 0.1–1m) is studied …

Analysis Of A Solar Hybrid Sulfur Ammonia Copper Oxide Thermochemical Cycle For Hydrogen Production, Moustafa A. Soliman, Abdel Moniem Abomosalam, Noran Shedid, Mohamed Othman, Toka Hatem, Marc Samer

Chemical Engineering

Solar energy conversion to hydrogen by water splitting is a promising technique because it is sustainable and environmentally friendly. One option for water splitting is through thermochemical cycles in which one of the steps is electrolytic or photocatalytic. In this paper, the economics of a thermochemical process that combines photocatalysis, photovoltaics, high temperature thermal energy and energy storage to harvest solar energy is assessed. This paper focuses on the standard hybrid sulfur ammonia thermochemical cycle (SA) in which the electrolytic step of the hydrogen production from ammonium sulfite solution is augmented by a photocatalytic step. Trying to make use of …

Performance And Economical Analysis Of Different Insulating Materials Used To Reduce The Heat Load Of An Existing Residential Building, Radwa A. El-Awadly, Ahmed A. Abdel-Rehim

Mechanical Engineering

The energy consumption from the residential sector is an important element which has an impact on the total energy consumption in any country. The heating and air conditioning loads can be reduced through many means. Using thermal insulation in buildings does not only contribute in reducing the required air conditioning system size, but also in reducing the annual energy cost for the whole building. In this case, the energy saving varies according to the building type, the climatic conditions at which the building is located as well as the type of the insulating material used. In the present study, an …

Effect Of Dust And High Temperature On Photovoltaics Performance In The New Capital Area, Engy Elshazly, Ahmed A. Abdel-Rehim, Amr Abdel Kader, Iman El-Mahallawi

Mechanical Engineering

The trend for integrating solar Photovoltaic Panels as an alternative renewable and sustainable energy source is growing in Egypt, North Africa and the Middle East. However, these efforts are not widely accepted by the society due to their lower efficiencies. The efficiency of the photovoltaic panels is affected by many environmental parameters, which have a negative impact on system efficiency and cost of energy, dust and increased panel temperatures being the most serious. This work presents the results of a case study conducted at The British University in Egypt at El-Sherouk city to study the effect of different parameters such …

Energy And Exergy Analysis For Stationary Solar Collectors Using Nanofluids: A Review, Mahmoud Eltaweel, Ahmed A. Abdel-Rehim

Mechanical Engineering

Fossil fuels demonstrate pollution effects and significant emissions on the atmosphere, which made the use of clean, renewable sources of energy a necessity. Renewable energy has many sources, but the most promising and cheapest energy source is solar energy, which has led to a focus on efficient solar energy harvesting to be cheaper for public use. Stationary solar collectors like evacuated tube and flat-plate solar collectors are the most commonly used solar collectors for their simplicity of installation and maintenance. They are mostly used for domestic applications such as solar water heaters. Nanofluids can improve the thermal properties of the …

Recent Advances In Preparation And Testing Methods Of Engine-Based Nanolubricants: A State-Of-The-Art Review, Sayed Akl, Sherif Elsoudy, Ahmed A. Abdel-Rehim, Serag Salem, Mark Ellis

Mechanical Engineering

Reducing power losses in engines is considered a key parameter of their efficiency improvement. Nanotechnology, as an interface technology, is considered one of the most promising strategies for this purpose. As a consumable liquid, researchers have studied nanolubricants through the last decade as potential engine oil. Nanolubricants were shown to cause a considerable reduction in the engine frictional and thermal losses, and fuel consumption as well. Despite that, numerous drawbacks regarding the quality of the processed nanolubricants were discerned. This includes the dispersion stability of these fluids and the lack of actual engine experiments. It has been shown that the …

Numerical Investigation Of The Thermal Performance Of An Axially Rotating Internally Finned Receiver Tube Of A Parabolic Trough Concentrator, Andrew S. Tanious,, Ahmed A. Abdel-Rehim

Mechanical Engineering

Enhancement of the thermal performance of the parabolic trough receiver tube is one of the approaches to energy sustainability. In the present work, the thermal performance of an axially rotating receiver tube equipped with internal flat longitudinal fins is studied. The effects of both the fin height and the rate of axial rotation are investigated at low values of axial Reynold’s number. The numerical analysis is held at various rotation rates using ANSYS Fluent. The numerical findings showed that the effect of the axial rotation on the internally finned receiver tube is not significant yet negative where a maximum reduction …

An Experimental Study Of A Hemi-Spherical Solar Collector Under Egyptian Climate, Mohamed Ebaid, Salma Salah, Ahmed A. Abdel-Rehim

Mechanical Engineering

Traditional flat plate collectors have shown, under many investigations, low system operating efficiency, which prompted the idea of designing new solar collectors operating with higher efficiency. Such designs include spherical, hemi-spherical, cylindrical, or rhombic solar collectors. The current study experimentally investigates the performance of a stationary newly designed hemi-spherical solar collector in comparison with a flat plate solar collector with the same surface area and weather conditions. This target has been achieved through designing and manufacturing a hemi-spherical collector, followed by analyzing its performance under normal operating conditions of Egyptian climate. The Hemi-spherical solar collector showed a maximum efficiency of …

Kinetics Of Photolysis And Photocatalytic Oxidation Of Ammonium Sulfite For Hydrogen Production, Moustafa A. Soliman, Maryam Zakaria

Chemical Engineering

The production of hydrogen via photocatalytic water splitting is one of the most promising technologies for obtaining chemical energy from direct solar energy while maintaining the least possible waste and pollutants. In this paper, we obtain the kinetic parameters necessary for the design of a photoreactor for photolysis and photocatalysis of ammonium sulfite solution. For the case of photolysis, we obtain the kinetics for the effect of changing the pH on the produced amount of hydrogen. For the case of photocatalysis, the intrinsic kinetic parameters of photocatalysis of water splitting reaction of ammonium sulfite and water in the presence of …

A Reduced Model For Microbial Electrolysis Cells, Dina Aboelela, Moustafa A. Soliman, Ibrahim Ashour

Chemical Engineering

Microbial electrolysis cells (MECs) are breakthrough technology of cheap hydrogen production with high efficiency. In this paper differential-algebraic equation (DAE) model of a MEC with an algebraic constraint on current was studied, simulated and validated by implementing the model on continuous-flow MECs. Then sensitivity analysis for the system was effectuated. Parameters which have the predominating influence on the current density and hydrogen production rate were defined. This sensitivity analysis was utilized in modeling and validation of the batch-cycle of MEC. After that parameters which have less influence on MEC were eliminated and simplified reduced model was obtained and validated. Finally, …

A Reduced Model For Microbial Fuel Cell, Dina Aboelela, Moustafa A. Soliman, Ibrahim Ashour

Chemical Engineering

Microbial fuel cells (MFCs) are a group of microbial electrochemical cells (bioreactors) that are used to generate energy from organic waste found in wastewater. MFCs represent a promising method of waste disposal and production of electricity. Scaling up the use of MFCs requires extensive analysis and detailed grasp of the required processes. The current work aimed to study a model of an MFC, and find the optimum parameters needed for maximum energy production. The process was simulated and validated on continuous-flow MFCs with a Columbic efficiency of 162% and 35% COD removal. Sensitivity analysis of the model was performed. The …

Numerical Investigation Of Darrieus Wind Turbine With Slotted Airfoil Blades, Ahmed Elbaz, Omar Sherif Mohamaed, Ahmed Abdelhamid Ibrahim, Ahmed Khaled Etman, Amr A. Abdelfattah

Mechanical Engineering

Low starting torque is considered as one of the major drawbacks of Darrieus type vertical axis wind turbine (VAWT). Design optimization to overcome this problem by modifying the airfoil geometry has received great attention by the wind energy community. Moreover, efforts have been directed towards augmenting the power coefficient of the turbine. In the present work, the effect of employing slotted airfoil as turbine blade on the performance and starting characteristics has been investigated. The slot parameters; slot location, angle of inclination, and dimensions, were optimized for NACA 0018 airfoil which is commonly used in Darrieus turbines. The flow over …

Exploiting Modern Image Processing In Surface Flow Visualisation, Tarek Ihab Abdelsalam, Richard Williams, Grant Ingram

Mechanical Engineering

Surface flow visualisation is an experimental technique where the surface of interest is painted with an oil and dye mixture before a flow is applied to the object. In regions of high shear stress the oil/dye mixture is then removed and in regions of low shear stress the oil/dye mixture stays or builds up. The resulting pattern can be analysed to determine the structure near the surface under test, this is normally done in a qualitative manner with flow structures being identified based on the expertise of the experimentalist. Modern image processing tools can identify shapes and lines in pictures …

Evaluation Of Solar Energy Solution For Egyptian Remote Areas, Tarek Ihab Abdelsalam, Tarek M. Hatem

Mechanical Engineering

Egypt is currently suffering the symptoms of the energy crises, such as electricity outage and high deficit as a result of constant increase in fossil foils through the last decades. On the other hand, Egypt has a high solar availability of more than 18.5 MJ annually. Additionally, Egypt has large uninhabited deserts on both sides of the Nile valley and in Sinai Peninsula, which represent more than 96.5% of the nation’s total land area. Therefore, solar energy is one of the prospective solutions for energy shortage in Egypt. Furthermore, these vast lands are advantageous for commissioning huge solar power generation …