Titanium alloys, notably Ti64, are highly valued in aerospace applications because of their outstanding specific strength, thermal stability, corrosion resistance. However, their machining is complicated by low thermal conductivity and a propensity for chemical reactions, leading to excessive heat generation. This study explores the performance of uncoated carbide tools when machining Ti-6Al-4 V under both conventional dry conditions and liquid nitrogen (LN₂) cooling, with cutting speeds varying between 60 and 170 m/min. The influence of machining parameters on cutting forces and workpiece surface integrity is analyzed. Findings reveal that LN₂ cooling raises cutting forces, attributed to the alloy’s enhanced hardness at cryogenic temperatures. Conversely, cryogenic cooling significantly enhances surface finish over dry cutting, with optimized cutting parameters effectively reducing surface roughness when using LN₂ cooling.
2025-07
Journal of Energy Storage
(القضية : 2024)
(الحجم : 101)
Application of an AI-based optimal control framework in smart buildings using borehole thermal energy storage combined with wastewater heat recovery
This article introduces a cutting-edge energy system to meet the residential building's high energy demands while lowering emissions and related operating expenses. The central concept revolves around rule-based control strategies designed to exploit wastewater's heat, accounting for a substantial amount of the total heating demand in residential buildings. The system is also integrated with heat pumps to recover the radiators' return water energy to preheat the ventilation air passively. Naturally-driven borehole thermal energy storage is added for post-cooling the ventilation air to incorporate higher renewable shares in building energy systems while lowering CO2 emission. TRNSYS and MATLAB software are used to design, control, optimize, and assess the system's performance from technological, environmental, and economic perspectives with the aid of artificial intelligence. According to the results, the proposed smart system is superior due to higher efficiency and lower energy cost while saving CO2 emissions compared to the conventional ventilation system. The results further show that the suggested smart integration effectively meets needs and reduces dependency on the centralized energy network by independently recovering or producing thermal energy through the developed control framework. According to the artificial neural network-assisted optimization outcomes, energy cost, total cost, and CO2 index are reduced by about 41.5 USD.MWh−1, 10,306 USD, and 1.7 kg.MWh−1, respectively. Furthermore, there is an annual extra 3 kWh of improved energy generation thanks to the optimal storage/usage of energy. The results further show that strategic optimization techniques like reducing mass flow rate and borehole depth perform well to maximize efficiency while reducing environmental impact and saving significant money.
2024-09
Sustainable Engineering and Innovation
(القضية : 2024)
(الحجم : 6)
A multi-sectional analysis of building height, layout, and urban density on seasonal energy consumption: A case study
This study aims to investigate the influence of building height and layout on energy consumption. It also analyzes methods for reducing energy consumption in these buildings. The EnergyPlus software performs simulations under local climatic conditions for all seasons. The city is divided into several sections based on cardinal directions, and energy consumption is calculated for each section, considering the city's distinct seasonal variations. Buildings in suburban areas with more sunlight exhibited higher overall energy consumption due to the reliance on heating and cooling systems, compared to the city center where denser urban areas moderated temperature extremes. Additionally, building design and insulation played significant roles. The analysis also revealed a west-to-east trend; higher consumption at the edges compared to the center. This is attributed to factors such as building density and shade from taller structures. The study further examined the impact of varying building heights. While most buildings were 20 meters tall, specific rows ranged from 21 to 25 meters. Changing these heights resulted in decreased cooling and increased heating demands in the north-south analysis, and reduced demands for both heating and cooling in the west-east analysis. This highlights the complex interplay between building layout, height, and energy consumption.
This study introduces an innovative multi-generation system powered by biomass, which aims to tackle the urgent problem of climate change by reducing CO2 emissions and increasing sustainability. The main problem being tackled is the ineffectiveness and environmental consequences of conventional biomass systems, which do not have methods for generating and injecting hydrogen. The proposed method combines solar panels with proton exchange membrane electrolyzers to generate green hydrogen, hence improving the quality of combustion byproducts. The methods utilized consist of integrating a supercritical carbon dioxide cycle with a thermoelectric generator to enhance the efficiency and cost-effectiveness of power generation. Additionally, flue gas condensation, a multi-effect desalination unit, and efficient waste heat recovery are employed to maximize the utilization of passive energy. The study concludes that under the optimal design, the proposed system outperforms the standard model that exclusively depends on biomass. The key results demonstrates that these characteristics are clearly demonstrated by its superior net power productivity of 3927 kW, exergy efficiency of 32.9 %, and drinkable water production rate of 9.4 kg/s. In addition, the suggested system has a lower levelized energy cost of 17.6 dollars per megawatt-hour and an emission index of 75.5 kg per MWh. However, upon comparing the rates at which exergy is being destroyed, it becomes evident that the majority of the components in the proposed model, such as photovoltaic panels and the electrolyzer unit, have a higher rate of exergy destruction. Ultimately, it can be noted that the fluctuations in combustion and turbine inlet temperature are crucial design parameters that substantially influence the power cycle and the system’s overall performance.
2024-07
Materials Today: Proceedings
(الحجم : 20)
Preparation and characterization of electrical properties of graphene oxide (GO)/epoxy composites
Epoxy composite of different content graphene oxide (GO) from (1.5 vol% to 6 vol%) have been fabricated
at (25 C) temperature. The (GO)/ epoxy composite were studied in terms of electrical properties.
The electrical conductivity of the composites is rises from 1.047 1010 (S/m) at pure epoxy to
3.37 1010 (S\m) when the GO content is increased to 6 vol%, scanning electron microscopy (SEM)
was shown the interface between the composite composition. The conductivity of composites have been
showed the transition from insulation to conduction when took place for graphene oxide to the pure
epoxy resin.
2019-10
Hbrc Journal
(القضية : 2)
(الحجم : 11)
Mechanical properties of graphene oxide (GO)/epoxy composites
n this study, the effects of graphene oxide (GO) on composites based on epoxy resin were analyzed. Different contents of GO (1.5–6 vol.%) were added to epoxy resin. The GO/epoxy composite was prepared using the casting method and was prepared under room temperature. Mechanical tests’ results such as tensile In this study, the effects of graphene oxide (GO) on composites based on epoxy resin were analyzed. Different contents of GO (1.5–6 vol.%) were added to epoxy resin. The GO/epoxy composite was prepared using the casting method and was prepared under room temperature. Mechanical tests’ results such as tensile test, impact test and hardness test show enhancements of the mechanical properties of the GO/epoxy composite. The experimental results clearly show an improvement in the Young’s modulus, tensile strength and hardness. The impact strength was seen to decrease, pointing to brittleness increase of the GO/epoxy composite. A microstructure analysis using Scanning Electron Microscopy (SEM) and X-ray diffraction (XRD) analysis was also performed, which showed how GO impeded the propagation of cracks in the composite. From the SEM images we observed the interface between the GO and …
2015-08
المؤتمرات العلمية
International Conference on Advancements in Polymeric Materials (APM2013)
2013-03
ELECTRICAL PROPERTIES OF GRAPHENE OXIDE /EPOXY NANOCOMPOSITE
The graphene oxide (GO)/epoxy composite was prepared using casting method and the electrical properties such as electrical conductivity, dielectric strength, and dielectric constant was studied using special multimeters (Agilent make). The potential of the GO/epoxy composites use in transistors and electronic industries are explored. GO/epoxy composites with different volumetric percentage (v/v%) contents of GO were prepared under room temperature and refrigerated curing conditions. The results showed that the conductivity and dielectric properties improved but the resistivity has decreased due to the presence of GO in the composite.
Proceedings of National Graduate Conference
2012-11
Mechanical properties of graphene oxide (GO)/epoxy composites
In this research, the Graphene oxide (GO)/epoxy composite of different contents of Graphene oxide from 1.5-6.0 vol. %, and epoxy resin was prepared under room temperature and refrigerated curing conditions. The composites show enhanced mechanical properties during the tensile test and impact test. This research aims to prepare the GO/epoxy composite using the casting method and to study the mechanical properties such as tensile strength, Young's modulus, and Impact strength. At first, the test specimens were prepared followed by the mechanical testing. X-ray diffraction was also studied for the various test samples. The experimental results indicate a considerable improvement in mechanical properties with an increase of GO content in the composite. Young's modulus and tensile strength increased. X-Ray Diffraction showed excellent dispersion of the GO in the epoxy matrix.
ورش العمل
University of Duhok
2017-04
Oil Field Safety
Oil Field Safety
2017
University of Duhok
2017-04
Pipeline Construction
Pipeline Construction
2017
University of Duhok
2016-11
Corrosion of materials
University of Duhok
2016
University of Duhok
2016-11
Materials Testing
University of Duhok
2016
University Tenaga National / Malaysia
2012-08
Avoiding Plagiarism in Academic Writing .
University Tenaga National
2012
University Tenaga National / Malaysia
2012-07
Thesis Preparation Using Latex.
University Tenaga National
2012
University Tenaga National / Malaysia
2012-07
Effective Oral Presentation Skill for Postgraduate Students.
